Tag: horticulture

Arslan et al. echo this conclusion, finding that opportunities for wage employment contribute to the empowerment of young women and the rural economic transformation by speeding up the demographic transition. The dynamics described above raise the prospect of farm labor shortages over time, especially shortages of wage workers needed to meet the growing demand for food and agricultural products. This situation is already observed in high income countries across the world. Global press coverage documents labor shortages and reliance on immigrant farm workers on every continent where crops are commercially grown . The COVID-19 pandemic has served as a stark reminder of high income countries’ reliance on immigrant agricultural labor. There are four options to deal with farm labor shortages, which Martin characterizes as the 4 S’s: Satisfy, Stretch, Substitute, and Supplement. Farmers can satisfy and retain existing workers by offering them higher wages, less onerous working conditions, benefits, and bonuses to make work on the farm more competitive. Farm employers can stretch the workforce by increasing worker productivity, providing workers with better technology like slow-moving conveyor belts to carry harvested produce that enable workers to pick faster. The option to substitute may entail replacing laborers altogether by labor-saving technologies or relying on food imports instead of local production. And finally, farmers can supplement the existing workforce with foreign guest workers. All four strategies are being deployed to different degrees, depending on countries’ preferences and their position in the evolving labor surplus-shortage continuum. The corresponding public policy domains are labor and social protection,pot with drainage holes innovation and competition, agricultural trade, and migration. These go well beyond the traditional realm of the Ministry of Agriculture.

This broad global assessment of the future of AFS work zooms in on the roles of productivity-enhancing innovation and technology and immigrant agricultural labor. The choice is motivated by persistent low labor productivity in African agriculture, the salient digital revolution, and rising anti-immigration sentiment in current policy debates. solutions . Others view research and development as largely an exogenous, self-perpetuating process: new inventions lead to others by lowering the cost of technological development over time . Both could be at work in practice, with the development of digital technologies, for example, partly driven by forces exogenous to agriculture, but their adaptation and adoption in agriculture partly driven by the rising costs of labor. A famous example of labor-saving technology in fruit and vegetable production was the processing tomato harvester developed by researchers at the University of California, Davis and commercially released by Black welder in the mid-1960s . Within five years of its commercial release, virtually 100 percent of processing tomato farms in the United States used the harvester, and most planted a tomato variety genetically engineered to go with it. Integrating mechanical engineering and agronomics was a novel feature of the tomato harvester’s genesis. Over the next 35 years, harvest labor requirements per ton of processing tomatoes dropped by 92%, while the U.S. processing tomato harvest more than doubled .Recently, R&D has combined mechanical engineering with information and technology to find labor-saving solutions for more difficult to-mechanize crops and activities . Automated harvest of fresh fruits, like peaches and strawberries, is particularly challenging, requiring “smart” technological solutions like mobile robots, mechatronic systems with precision sensing, actuation capabilities, and robots that can handle soft, flexible, and complex objects.

These machines and other sensors also gather data, which, in combination with cloud connectivity, advanced analytics, and machine learning algorithms, create a world of new possibilities to manage and increase efficiency along agri-food chains. The result can include a reduction in the use of other inputs, as well as labor, reducing the adverse impacts of food production on the environment as well as on farm workers’ health, for example, by reducing chemicals in the food chain. Many of these high-tech solutions are still in the development and experimentation stages, but others are “on the shelf” and already in common use . Clearly, if ever it was accurate to think of agriculture as an intrinsically low productivity sector, that time has passed. California’s tomato harvesters and “robots in the fields” seem far away from farms in low-income countries. Nonetheless, increasing agricultural labor productivity in the developing world will require increased use of technologies that enable the agricultural labor force to become more efficient and remain inter-sectorally competitive . As a result, agricultural productivity gains in much of the world may need to be induced primarily by more basic technologies, like small tractors, or mechanical devices that automate repetitive labor intensive tasks, such as mechanical rice transplanters. In some places, expansion of agricultural machinery services offers the possibility of increased mechanization on farms too small to justify the outlay to purchase machinery themselves. For example, Yang et al. report that in China, “in response to a rising wage rate, the most power-intensive stages of agricultural production, such as land preparation and harvesting, have been increasingly outsourced to special service providers.” In China, the use of these services has promoted a more efficient division of labor, allowing urban migrants to maintain higher-wage employment off the farm during the planting and harvest seasons . The increasing use of machinery services is not confined to Asia. It is also observed in Africa and increasingly facilitated by digital platforms, such as Hello Tractor in Nigeria,an app-based Uber connecting smallholder farmers to affordable tractor service providers.

Nonetheless, many organizational hurdles to developing the integrated machinery chain needed to make it profitable remain . Socioeconomic constraints can also stand in the way. Gulati et al. , for example, report low adoption of mechanical rice transplanters in India due to women’s weak bargaining position in the household decision making process. Mechanization is often associated with a reduced demand for labor. In theory, the impact of mechanization on labor demand and wages is unpredictable. This is because of two opposing effects: substitution and scale. Agricultural mechanization often occurs in response to rising rural wages, following the structural transformation of national economies towards industry and services, which draws labor out of the agricultural sector. As rural-urban migration expands, greater urban income earning opportunities become the main driver of agricultural wages. Higher wages induce farmers to mechanize and substitute capital for labor, as has now also been observed in Vietnam . Mechanization can also enable farmers to expand the scale of their production and increase their income. This can even happen without an original increase in wages, especially in land abundant countries. In fact, it can even induce an increase in real agricultural wages and hired labor , though the use of some intermediate labor-saving inputs like herbicides can mitigate this . An observed concurrence of rising agricultural wages with mechanization would suggest that wages induce farmers to adopt labor-saving methods, but when scale effects outweigh substitution effects, mechanization does not necessarily reduce rural employment. It is not surprising, therefore, that the evidence on the labor effects of mechanization is mixed. Kirui reports that in African countries where land expansion previously was limited, mechanization has led to scale effects through an increase in the amount of cropland cultivated . Scale effects have been accompanied by input intensification, higher productivity in maize and rice production, and greater labor use. However, in a number of countries, he also finds that mechanization displaces labor and induces off-farm work in some cases. Overall, where there are limits to agricultural extensification, for example, due to labor scarcity and rising wages, increasing labor productivity through technological change, including mechanization,large pot with drainage is the key to expanding food supplies.As technology changes, better educated and trained workers will have to be available to complement new advanced technologies.

Digitized agriculture and food systems also require a digitally-skilled workforce. In most cases, technologies and skill demands in poor countries are not as advanced as in high-income countries like the United States, Western Europe, or Japan. Nonetheless, studies from developing countries reinforce the need to train workers for more skill-intensive employment, not only on farms but throughout the food supply chain, as the agricultural transformation unfolds and digital agriculture takes hold . The COVID-19 crisis may present an opportunity to accelerate the digitization of the agri-food system, helping players across the globe in all nodes of the AFS become more efficient and informed while bridging the ruralurban divide by improving participation in modern markets . Solar energy and mini-grids also offer important opportunities to increase labor productivity in agri-food, especially now that the cost of productive use leveraging solar energy products, such as solar driven water pumps , cold storage, and agri-processing equipment, is falling, appliance efficiency is increasing, and new business models are emerging.The two main policy areas for promoting mini grid expansion and greater adoption of PULSE products are becoming financially sound, through charging cost recovery tariffs and/or targeted government subsidies and having regulations that specify what happens when the large grid reaches the mini-grid areas. On both fronts, many initiatives are ongoing . The adoption of these technologies could accelerate agricultural labor productivity growth, especially in Africa and South Asia; enable the development of delocalized agri-processing through refrigeration; and facilitate a more productive release of farm labor. In countries further along in the development process, the transition out of agricultural work is often accompanied by an inflow of immigrant workers, who help grease the wheels of farm labor markets by replacing native-born workers no longer willing to do farm work . Reliance upon immigrants has been a quintessential feature of the history of farm labor in the United States, particularly in the state of California, where two thirds of the nation’s fruits and nuts and one third of vegetables are grown. It is also widespread in other high-income economies, as well as many not-so-high-income ones like Costa Rica , Dominican Republic , and South Africa . In recent decades, California farmers have relied overwhelmingly on unauthorized migrant workers from Mexico. However, rural Mexicans are also transitioning out of farm work as families become smaller, children become better educated, and non-farm employment expands . Workers have become less willing to travel far away from their homes to work on farms for extended periods of time . Yet, when farm workers are less mobile, even more are needed to meet seasonal labor demands.The declining supply of immigrant farm workers and their reduced mobility has induced local labor shortages. In some cases, this has prevented farmers from being able to harvest high-value fruit and vegetable crops, which have simply rotted away in the fields . Expansion of the U.S. H-2A agricultural guest worker program is unlikely to offer a long-term solution, as labor recruiters compete with Mexican farmers for a diminishing number of farm workers. Mexico is expanding its fruit and vegetable production, in part, by importing farm workers from Guatemala, while sending fewer farm workers to the United States. Increased immigration enforcement has further led to an exit of immigrants from local farm labor markets and pushed unauthorized Mexican migrants further into the desert to avoid apprehension, leading to an increase in the number of border-crossing deaths . These factors have exacerbated an already deteriorating situation for U.S. farmers and have led to a humanitarian crisis on the U.S.-Mexico border. These trends are not specific to California or Mexico. They have been observed across high-income countries and are evident in other middle-income countries. Agricultural guest worker programs are common on all continents, in countries with vastly different incomes, and they tend to be controversial everywhere. The extent to which middle- and high-income countries already rely on immigrant labor has been highlighted by the COVID-19 pandemic, which caused governments across the world to enact emergency measures to relax mobility restrictions for agricultural workers to safeguard food production. Examples include the U.S. , Canada, Germany, and Spain , and Portugal and Italy . Migration can benefit migrant-receiving areas, beyond the farmers themselves, to the extent that migrants complement native workers, make agricultural operations more competitive, and stimulate the demand for goods and services. More importantly, from a development perspective, migration can benefit those who remain in the migrants ending economy . Migrant farm workers often earn much more than they could in their place of origin, and the income they remit to family members can help loosen constraints on household production activities, generate income spillovers for other households, and create other positive externalities.

Both studies detail establishment and first year production and harvest costs for not-yet-fully-mature crops. For raspberries, first year of production includes a $12,460 per acre construction, management and investment cost for protective tunnels. Costs for a mature raspberry crop are analyzed in the second production year and total $48,210 per acre . For blackberries, costs for a mature crop are shown for the second through fifth production years, and total $43,406 per acre per year. Harvest costs again represent the vast majority of total costs, at 81% and 71% of total costs for raspberries and blackberries, respectively. For raspberries, cultural costs represented a much smaller share of total costs at $4,656 per acre, roughly half of which was for trellis and tunnel management. Blackberry cultural costs totaled $5,709 per acre, of which over half was for pruning and training canes. Each study also includes an analysis of potential net returns to growers above operating, cash and total costs for a range of yields and prices. When evaluating net returns above total costs, gains are shown for higher yield and price points; losses are also documented at many lower yields and prices . Farms with productive soils, experienced managers, optimal production conditions and robust market plans generally realize higher net returns. In contrast, farms with less-than-optimal production conditions, reduced yields, poor fruit quality or inexperienced managers may contribute to lower net returns. Results from the strawberry analyses show that on a per acre basis,vertical vegetable tower organic strawberries tend to be more profitable than conventional berries, even with lower yields.

Organic price premiums explain the result; in this example price per tray for organic strawberries ranged from $12 to $18, while price per tray for conventional berries ranged from $7.30 to $11.30. Prices for second year conventional strawberries were slightly lower still to account for a portion of the crop that was diverted to the freezer market. Net returns for both caneberries were mostly positive. Other noteworthy entries in all recent berry studies include per acre costs for pest control advisers , management of invasive pests and food safety and regulatory programs for water and air quality. Though each alone represents a relatively small portion of total costs, they provide readers with insights into the changing nature of berry production activities and costs over time.Cultural practices in the berry industry have evolved to address changes in soil, water and pest management needs. New varieties have been developed to enhance yield and quality attributes. Based on historical trends, and to meet both industry needs and consumer demands, we expect to see new varieties continually developed over time. Businesses have responded to consumer and market demands for fresh, safe and organic products by implementing food safety programs and/or transitioning more lands to organic production. Water and air quality programs have been developed to comply with state regulatory requirements. In the past, growers customarily hired those with expertise in financial and market management; they now also enlist the support of experts in food safety, organic agriculture and environmental quality to assist with farm management. But challenges remain, and management of key agricultural risks — including those for production, finances, marketing, legal and human resources — have become increasingly important.

Invasive pests pose significant management and regulatory constraints and increase production, financial and market risks. Two recent examples are light brown apple moth and spotted wing drosophila . LBAM infestations can lead to loss of part or all of the crop because of field closure from regulatory actions, increasing production and financial risk. SWD presents substantial market risk to growers in that its larvae can infest fruit and render the crop unsaleable. Growers minimize the risk of loss from these two organisms with the routine use of PCAs. PCAs monitor fields more frequently than growers alone would be able to do, identify pests and recommend actions, for example, the use of pheromone mating disruption for LBAM and field sanitation for SWD.Since their introduction, the soil fumigants CP and MB have unquestionably contributed to the expansion of the berry industry. However, the full phaseout of MB as a pest management tool — it will no longer be available for use in berry production after 2016 — presents both production and financial risks. While a substantial research commitment has been made to finding alternatives to MB, nothing has yet come close to offering the same level of protection from the large-scale loss to soil pathogens or the gains in productivity associated with the application of CP and MB as synergistic preplant fumigants. We anticipate that the berry industry will adapt to the MB phaseout by using alternative fumigants and preplant soil treatments, but these are likely to carry a higher level of risk for berry production in the short term and may lead to a decrease in planted acreage and production. However, this may also stimulate an even more robust research agenda directed towards soilborne diseases and plant health to minimize disruption to the industry. Reliance on fumigants as the primary strategy for pest management is almost certainly a thing of the past. Instead, adoption of integrated approaches, including alternatives to fumigants, to manage diseases, weeds and other pests will be key to sustaining berry production over the longer term .

Social and demographic changes in Mexico — the source of a majority of the area’s agricultural labor — have resulted in markedly lower immigration rates into the United States, a shrinking labor pool and upward competition and wage pressures for the agricultural workers who remain . In recent years, growers have reported difficulty in securing and retaining sufficient numbers of workers to ensure timely and effective farm operations. The lower production figures seen in strawberries in 2014 may in part have been the result of an insufficient labor pool from which to draw . However, no known regional employment or wage data are available to specifically document this. Some growers minimize labor risk by paying higher wages and providing year-round employment when possible. However, these strategies can be difficult for some businesses to justify economically. Arguably, the area’s berry industry, and agriculture more generally, increasingly face political risk. Immigration legislation that may assist with the current labor challenge languishes at the federal level, with major policy changes unlikely before 2017 . Farming practices are under ever more scrutiny by consumers, local municipalities and state and federal agencies. Soil fumigants and pesticide use have been the focus of many intense debates and discussions, especially in Santa Cruz and Monterey counties. At the time of this writing, several new regulations related to pesticide application notifications, pesticide and fumigant application buffer zones and worker safety have been proposed by the California Department of Pesticide Regulation or the U.S. Environmental Protection Agency but have not yet been finalized. It is anticipated that implementation will begin in 2017, with full compliance required in 2018. And, as California struggles through a fifth year of drought, water use, quality and cost has become a more robust part of the local, state and federal discourse, with directives issued and new legislation proposed. Compliance with each new directive or regulation presents production and logistical challenges for growers and can be costly to manage. Although it is unlikely that regulatory pressures will lessen in the future, there is every expectation that growers will continue to adjust business practices to meet or exceed any new requirements or standards. The economic sustainability of individual farming operations and the area’s berry industry in total will ultimately be impacted by and continue to evolve with the ever changing business environment,vertical farm tower and by an array of risks and challenges.While there is evidence that drought causes individuals to reduce water consumption, household demand remains somewhat inelastic . In periods of drought, the majority of water reallocation falls to industrial consumers and in particular the agricultural industry which consumes 80% of non-environmental allocated water in California . While this may spark scarcity innovation through investing in new technology or selling and trading water permits, there are substantial costs from unexpected changes to a water supply. In this paper, I investigate whether drought can create local spillovers into sectors closely related to the agricultural industry, using the distinct variation in drought intensity to compare compositionally similar counties.

Empirical evidence suggests that price volatility in times of crisis creates considerable spillover in closely related industries . I attempt to test this hypothesis with the 2012 to 2016 California drought, a hydrologically significant event that primarily impacted the Central Valley. I use cross-sectional data to analyze outcomes utilizing a difference in difference methodology to compare the counties in the Central Valley that experienced a greater intensity of drought with those that narrowly evaded costly impacts. Drought creates reductions in water supply that cause farmers to employ large-scale shifts to groundwater usage, less water per crop and increased reliance on water-conserving technology . Over pumping groundwater has the potential to create unquantifiable long-run impacts on the environment and permanently reduce the natural ability to replenish available aquifer levels.1 In future drought occurrences, lower levels of groundwater will increase pumping costs, particularly in Central Valley counties that relied heavily on groundwater from 2012 to 2016 . Although groundwater pumping is common, farmers that require more water than what is available from either state allocated water contracts or pumping face several choices. They can sell state allotted water permits to industrial consumers to recover a portion of losses, switch to drought-tolerant crops, or fallow portions of farmland.Fallowing is often the last choice, as farmers forgo all profit generated from owning and operating the property and are likely to reduce the hours their employees work. Fallowing creates sizeable direct costs to the industry in productivity and job loss .California agriculture is the national leader in terms of food sales, making up 11% of total exports in 2012. The lucrative industry was valued at $37.5 billion in 2012 and has been growing rapidly. Despite the drought, agricultural exports had a valuation of $46 billion in 2016 . Estimates suggest output would have been much higher if the drought had not occurred. Total direct statewide economic losses to agriculture from the drought were $3.8 billion solely from 2012 to 2016 . We know the 2012 to 2014 drought in Southern and Central California was the most severe occurrence in the last 1200 years by paleoclimate reconstructions of past droughts . The impact of the drought in terms of crop losses and job layoffs manifested primarily in the Central Valley, an inland area consisting of 18 counties. An estimated 72% of the crop losses in the height of the drought were contained in the San Joaquin valley and Tulare River basin . Although agriculture statewide did not sustain extreme losses, job losses and pumping costs were distributed unequally. After using groundwater pumping to recover the majority of the water shortage, the remaining 10% shortage in statewide agricultural water use was accommodated by fallowing half a million acres of farmland. Approximately 90% of that fallowed land was in the San Joaquin Valley and the Tulare river basin. Other compositionally similar areas such as the central coast depend on different water sources that were not similarly impacted by the drought . The 2012 to 2016 California drought highlighted the inadequacy of rural well and water systems, particularly in certain rural communities that lacked running water at the height of the drought. Tulare county suffered one of the greatest losses in crop production as well as bearing one of the highest costs of groundwater pumping. Due to reduced groundwater levels in Tulare, there were approximately 2,000 domestic well failures solely in 2015 . These small and often low-income areas are not always required to have contingency plans or links to larger water supply systems. Related literature has shown that rural and low-income individuals have less tolerance for natural disasters. A similar drought occurred in Australia from 2001 to 2004 and was estimated to be equivalent to an annual reduction of $18,000 in income. However, this impact appeared only for individuals living in rural areas . This result emphasizes differences in responses between demographic groups to natural disasters. Current literature aims to understand this differential to effectively implement welfare programs such as the relatively new Drought Housing Relocation Assistance Program implemented in 2015 .

It is worth mentioning that at all the three tiers of sites, cross-scale sensing technology should be able to provide already rich remote-sensing based observations, which should provide the necessary model inputs and model constraints for MDF. Tier 1 – Super sites: This tier includes sites that have collected a complete suite of measurements data that can be regarded as gold standard datasets . An ideal super site should include measurements that range from biogeophysics to biogeochemistry , i.e. a dataset that is sufficient to recreate the soil-plant-atmosphere continuum, and evaluate/benchmark the major ecosystem processes simulated by models. Thus a typical super site should at least include eddy-covariance flux tower, extensive and deep soil samples, ground-level remote sensing, and various other advanced measurements . Existing examples of research infrastructure that already supports many of these “gold-standard” data variables include the USDA Long-Term Agroecosystem Research network, some National Ecological Observatory Network sites, and AmeriFlux sites on cropland and pasture land . Further, the recently launched U.S. Department of Energy ARPA-E SMARTFARM sites have been collecting soil, crop, and GHG fluxes data with even greater spatial and temporal resolutions , enabling a new generation of R&D development such as high-resolution remote sensing monitoring, or novel modeling methods that can capture granular dynamics such as hot-spot and hot-moment patterns of GHG emissions. Tier 1 super sites would enable detailed model calibration and out of-sample validation by virtue of the fact that gold-standard datasets capture whole ecosystem flux , soil carbon flux and stock, plant biomass etc. What would make the Tier 1 super sites more useful is to add paired experiments with detailed measurements for the pairs.

For example,vertical gardening in greenhouse setting up two neighboring sites with one growing cover crop and the other not, and keeping other management practices the same or similar enough, the difference of measurements could provide strong scientific evidences and thus validation data for quantifying the carbon outcome of different management practices. Successful examples of paired experiments with eddy-covariance flux measurements have been demonstrated in rice methane emission using alternate wetting and drying . Super sites also provide further validation for the cross-scale sensed E, M, C variables. Tier 2 – Intermediate sites: This tier includes an extensive number of sites that only have a few key ground measurements but do not have a complete suite of observations as the Tier 1 super sites. Using these ground measurements and also remotely sensed observations, MDF can be conducted, and validation can still be made directly to compare the simulated crop yield, SOC stock and SOC changes with ground observations. When doing model validation at the Tier 2 sites, only basic information about site location and management history will be provided, and the modeling team should report their simulation results for independent comparison with observations. Tier 3 – Scaling sites: This tier includes virtually any site or field that requires carbon outcome quantification. Little or no ground measurements are available at these sites. This tier of sites thus represents the real-world situation for operational use. However, using the cross-scale sensing technologies , all random fields will still have a suite of remotely sensed E, M, C data available to enable MDF and quantify both carbon outcomes and associated uncertainty at all these fields. Model verification at every field is also made possible when extra remotely sensed observations can be used as independent validation data. It is worth noting that Tier 3 almost entirely relies on remotely sensed and/or public-database E, M, C information, which highlights the importance of cross-scale sensing to enable such a new MDF approach. Looking forward, the “System-of-Systems” solution will be the most promising technology for field-level carbon outcome quantification.

One of the biggest advantages of the “System-of-Systems” solution is that it is an inclusive framework that can embrace new technology and has the potential to ingest new scientific discoveries and information, and thus can continue to evolve with the whole scientific community and technology trends. While prototypes of such a “System-of-Systems” solution are emerging for certain crop types and geography , this integrated system consists of several components that are still at their early stages, thus requiring considerable R&D investment by government and industry. Coincidentally, these investments will build the foundation for the next generation of precision agriculture whose scope has been expanded from increasing productivity and efficiency with site specific management , to the integration of sensing, big-data analytics and automation for guiding sustainable farming . However, technical advances alone are insufficient for substantiating the agricultural carbon market or agricultural sustainability more broadly; success will also rely on synergies among citizens, researchers, corporations, NGOs and governments to remove scientific and practical hurdles. First and foremost, we should fully acknowledge that agricultural carbon outcomes are deeply rooted in complex agroecosystems, and a holistic system view of carbon, nutrient, energy, and water cycles strongly coupled with human management should be the guiding principle. Above ground and below ground processes of carbon cycle collectively determine the SOC change , thus only focusing on changes in soil carbon pools while neglecting other critical carbon processes may lead to limited success. The tight connection of carbon cycle with other biogeochemical cycles and water cycle also highlights the importance of soil moisture, soil oxygen and chemical characterization of litter, which links SOC with the GHG emissions . Many unknowns about these above linkages exist . Coordinated research on understanding the holistic carbon nutrient-water cycles for agroecosystems is a priority that could be effectively pursued by leveraging the Integrated Model-Observation Experiment Paradigm . ModEx promotes the idea that models should be developed with the current best knowledge and corroborated with observational and experimental data, and models are then used to identify opportunities for additional field and lab-based research to fill gaps in further understanding system structure and function.

Second, we should use community efforts to develop unified protocols that guide measurements and modeling schemes to understand and reduce the uncertainty of carbon outcome quantification. Such protocols must be established through collective effort to achieve scientific rigor and transparency. Existing efforts led by certification organizations such as Verra and Climate Action Reserve are important and valued, but tend to be simplistic, conservative, and not always well-adapted to the nuances of production agriculture, given the limited empirical data and insufficient MRV tools . To successfully establish public confidence in low-carbon bio-energy feedstock, climate-smart commodities and agricultural carbon credit markets, a concerted effort of more advanced field work, data collection, and modeling assessment will be necessary. It is anticipated that debate will intensify as more disciplines and stakeholders become involved in the new phase of protocol development and validation,greenhouse vertical farming especially when the necessary rigor requires technical sophistication beyond traditional quantification approaches . To foster open and constructive conversations that increase credibility and the public confidence in carbon outcome quantification methods, three principles must be emphasized. First, the quantification uncertainty of field level carbon outcomes must be emphasized, and especially for the market-based instruments, such as climate-smart commodities and carbon credit markets, the uncertainty of the calculated carbon benefits should be reflected in climate-smart commodities’ price premium, or carbon credits pricing and policy design to ensure that the incentivized impact is not over- or under compensated. For example, the standard deviation of a MRV system can be used to discount the value of credits generated . This is an essential requirement for the protocol to be usable, not just a subjective technical preference. Second, validation is the only way to report system-wide uncertainty. No exemption should be made for any quantification tool, even if the tool is widely used or peer reviewed. There are some academic-based model intercomparison MIP efforts that can shed light on how to set up such validations, but given the transaction purpose of carbon credits, a high bar must be set for acceptable model performance. Third, demonstrating performance at the scale of an individual field is critical. Due to the challenges of achieving scalability, some practitioners suggest compromise by focusing on the aggregated accuracy of quantified carbon credit . We argue that aggregated accuracy, which is almost impossible to validate, must come from field-level accuracy. Next, establishing high-quality and comprehensive datasets and inter-comparison infrastructure for developing, calibrating, and validating MRV systems of carbon benefits is essential to building stakeholder trust in these market-based emission reduction instruments. The high-quality and comprehensive dataset to represent the three Tier validation system should ensure site representativeness to include different soil, weather, crop, and management types, and be open-source but compiled under a protocol of community-wide acceptance. An analogy is the Image Net database for computer vision and AI research, with which new algorithms will be bench marked to show their progress in visual object recognition.

Establishing an “Image Net for Agriculture” is certainly more challenging given the complexity of carbon quantification. Due to the often large uncertainty associated with agricultural measurements, protocols for standardized data collection, and processing techniques must be carefully evaluated and imposed. Some long term experiment and observation networks have collected a complete suite of E, M, C variables and have the great potential to provide high-quality and comprehensive data. Lastly, a large number of controlled experiment sites can be used to test the model scalability. These sites often have limited amounts of ground measurements but represent the real-world conditions for operational use. Further investment in high-quality data collection should prioritize experiments that can help understand the carbon outcomes associated with different bundles of carbon-outcome-related practices, such as the combination of no-till and cover crop, as well as measurements that can disentangle the opaque “black box” of complex plant-soil-microbe interactions . In addition, deep sampling of soils beyond the typical surface sampling depths is necessary to accurately quantify the extent of SOC changes and to corroborate estimates by models. Developing cyber infrastructure to ensure archiving and sharing of the scientific data is also highly important and should be an investment priority. Such cyber infrastructure development should be guided by the FAIR guiding principle for the collected scientific data management and stewardship , with a thorough consideration of privacy protection of farmer data. Finally, while our discussion has mainly focused on agricultural carbon outcomes, it is important to note the myriad environmental and economic co-benefits , which in turn can bring further benefits to carbon mitigation programs per se. Some recent case studies have demonstrated that, given the relatively low carbon credit price, participation of farmers may be primarily driven by these cobenefits . The “System-of-Systems” framework proposed in this perspective can be extended to assist the accounting of these co-benefits, and inform sustainable agroecosystem management by holistically studying the often coupled carbon, water, and nutrient cycles and human activities, a topic itself at the frontier of Earth system science. Poverty, often defined as very low socioeconomic status or lack of material wealth, negatively impacts almost every aspect of human biological functioning . It undermines growth and development, compromises basic physiological functions like immunity, intensifies disease, and worsens mental health . Lack of material wealth is a fundamental stressor in humans, both in terms of lack of access to basic needs, but also because of the low power and stigmatized social meanings attached . In studies that treat poverty as a driver of bio-cultural variation, “poverty” is most often operationalized as lack of wealth within the cash economy . Direct measures often focus on assessment of income or purchased material assets like housing materials or vehicles . Other often applied proxy measures are related to consumption or current or predicted participation in the cash economy like occupation or education . Recently, a study by Hadley, Maxfield and Hruschka , clarified that a dimension of agricultural wealth independent from cash economy wealth can show very different associations with human biological outcomes compared to those based in the cash economy. They found in a study of households in several sub-Saharan African countries that success in the cash economy was associated with increased risk of HIV infection, while success in agricultural activities often proved protective against that risk. Here we expand on the proposition that poverty measures giving primacy to the lack of success in the cash economy could overlook a crucial dimension of poverty that is important for understanding associations with well being, specifically the potential buffering role of agricultural forms of household wealth.

Greek peasants turned to vine monoculture, with most of the currant exports now destined for France as well as Britain. The phylloxera crisis in Europe ushered in a third phase of the extension of currant vineyards that lasted from 1878 to 1893. As global demand for Greek currants inflated to unprecedented levels, the monocultural currant-growing region in Greece extended further, well beyond the traditional currant region around the Gulf of Corinth. Currants spread south to the region of Messenia in the Southern Peloponnese, which had never been a currant region before, and by the end of the century, the southern coast of the peninsula had displaced the north as the primary currant-cultivating region. The French market that emerged after the Phylloxera epidemic preferred currants from the southern Peloponnese, because although they were lower quality, they were cheaper, and the lower quality was appropriate for the making of raisin wine.Thus, from the 1860s to the 1890s, the currant-growing region expanded and moved from a system of diversified agriculture to a state of vine monoculture. Nevertheless, currant specialization was geographically limited to the north and west coasts of the Peloponnese and the Ionian Islands of Kephalonia, Zakynthos, and Ithaki. The currant region did not expand to encompass the entire peninsula, much less the whole of Greece. In terms of the total area of the cultivated land of Greece, currant vineyards only occupied about 6% throughout the period of most intensive cultivation—keeping in mind that during this period,hydroponic net pots the Kingdom of Greece added the currant-growing Ionian Islands to its borders, but it also added Thessaly, which was not a currant region.

Despite its outsize role in the Greek export economy, it is important to note where, specifically, the choices were made to switch from diversified agriculture to monoculture, and to currant monoculture, specifically. This is not to say, however, that commercial agriculture was limited to these places, and that the rest of the peninsula remained committed to traditional agricultural practice. Rather, agricultural activities became specialized, intensive, and commercial in various parts of the peninsula, but it took different forms in other regions. Some of these activities were adjacent or supplemental to “currant mania,” such as the specialization in wine grapes, timber production in the mountainous inland regions of the peninsula, and the corresponding industrial activities, making timber into stakes and barrels, and making grapes into wine. Other regions specialized in different agricultural commodities, sometimes for export and consumption abroad, particularly olives and livestock. It is also worth noting that, while the currant zone was geographically limited, other varieties of vitis vinifera were ubiquitous. Unlike currants, the common grape vine is a very versatile crop, and it thrives in a variety of climates and soils.At the same time the currant region was advancing toward currant monoculture, the Peloponnese as a whole was becoming more devoted to vine monoculture. In the currant region, the extension of currant vineyards was accompanied by the extension of other vineyards. In the deme of Patras, the percentage of cultivated land devoted to currants increased from 5% in 1833 to 43% in 1861. In the same period, the percentage of land devoted to other vines increased from 3% to 28%. Thusin 1861, almost 71% of the cultivated land in the deme of Patras was growing vines.The increase in wine production was part of the same trend toward intensification, specialization, and commercialization in Greek agriculture. Wine was primarily produced for household consumption, but wine was also one of the main exports of Greece. The others included olive oil, leather and hides, cocoons, acorns, and figs.The production of these other commodities also increased along with currants. The extension of vineyards and the move to vine monoculture also led to the creation of a small wine making industry in Patras. After the emergence of the market for raisin wine in France, most wine making was done in that country, with raw currants being exported to France to be made into wine there. In Paris in 1890, there were twenty factories for producing wine from currants.However, a local wine making industry did also develop in Patras.

The first attempt to start a wine making industry was in the recovery from the Oidium crisis. In 1858, Wine making A.E. was founded, and operated 16 wine making factories in Patras. Because of the uncertainty caused by dependence on foreign demand, Wine making A.E. tried to create a domestic market for currants to be consumed as raisin wine.98 However, with the recovery of the currant vineyards from Oidium, the imperative to protect the currant industry from the whims of foreign markets faded, and Wine making A.E. failed. In the 1870s, however, Patras did become a wine making center after British and German entrepreneurs invested in the local wine making industry. In 1873, the German businessmen Gustav Klauss and Theodor Hamburger founded a joint-stock company called Achaia which manufactured spirits and red port wines from Greek grapes and currants. Three to four Greek companies also formed to manufacture wine.The currant economy collapsed due to the disappearance of French demand and the emergence of new competitors. First, the demand from France, which proved so crucial to sustaining the extension of currant vineyards in the 1880s, disappeared. French agronomists discovered that grafting European vines to North American roots made them immune to the phylloxera aphid. American vines had grown resistant to the aphid after centuries of co-existence and could thrive even with phylloxera living on their roots. Over the course of the 1880s, American roots spread to vineyards throughout France, and French production began to recover. The area of vineyards in France with American roots grew from 2,500 hectares in 1880 to 45,000 in 1885.100 The recovery of the French wine industry was not immediate, however, as raisin wine made from Greek currants had found a loyal market in France. Currant wine was popular among lower-class, urban consumers who liked it for its sweet taste.

It was also more affordable than domestically-grown French wines and was taxed at a lower rate. Working people could buy currants and make their own wine at home for 5 times less than the price of French-grown wine. Currant wine also kept better than regular wine. French vineyards were recovering, but they faced stiff competition from raisin wines and struggled to regain control of the market.101 When their vineyards were recovering but they were not able to sell their product, French vineyard-owners took to the streets and set up barricades to push for an import duty on raisin wines, and the French government responded with protectionist measures. In 1889, the Chamber of Deputies passed the Griffe Act, prohibiting raisin wine from being marketed as wine, and mandating that all wine made with currants be sold with a label prominently affixed that indicated it was “currant wine.”When this proved ineffective to curb the consumption of currant wine, the next year, the Chamber imposed a manufacturing duty on currant wine of 4s. 8d. per cwt. of currants. This was more effective,blueberry grow pot but currant wine consumption continued. From 1892 to 1896, the Chamber raised the import duty three times, from 2s. 4d. per cwt. to 6s., then to 10s., and finally to 19s. With the 1896 tariff, the French taxes on currant wine amounted to five times the cost of the product itself. In 1897, legislation was also passed to raise the tax on raisin wines to be equal with the tax on all other wines, but the market for currant wine was effectively dead in France by 1896.Currants did not disappear from Greece after the collapse of the currant economy in the 1890s. They remained an important cash crop long after the currant crisis. In fact, in the immediate aftermath of the crisis, currant cultivation continued to grow. In the wake of the crisis, those involved in the currant industry, particularly in Patras, organized to call for state intervention. In 1895, the Greek Parliament passed a plan for state retention of surplus currant production. The state would retain the estimated excess production of currants based on the previous year’s consumption, and these currants would be directed toward promoting the domestic wine making industry. The law required currant exporters to deposit 15% of their inventory at a government storehouse to be sold domestically at reduced rates. In addition, the revenues from these sales would be deposited in a Currant Bank , established in 1899, and the accumulated capital would be used to assist currant growers in the future.112 At first, the retention act succeeded in promoting a domestic wine making industry, and distilleries opened throughout the country. The act thus succeeded in the short term in creating a domestic demand for currants—something that had not existed in Greece before—but the act was amended to prohibit the use of retained currants for wine production. The goal was to compel producers to buy currants at market rates rather than reduced rates, but the additional cost constrained the growth of this new industry.

The retention act, moreover, did nothing address the problem of the overproduction of currants—if anything, it removed disincentives to grow— and currant production continued to rise.The 1903 surplus was huge, and the National Bank of Greece, the Bank of Athens, and the Ionian Bank all had to lend to the Currant Bank. In 1904, a bill was passed that taxed new currant plantations and substituted the export duty on currants with a 15% duty in kind, having the effect of increasing the amount of retained currants.Eventually, an equilibrium was found, and the migration of rural populations alleviated the rural labor surplus. Currant cultivation continued to be strong in the traditional currantgrowing core—Zakynthos, Kephalonia, Patras, Vostizza, and Corinth—which produced high quality currants purchased by Britain for consumption in puddings. This market remained unaffected by the closing of the French market, which preferred lower quality currants from the southern Peloponnese to be made into wines.The newer currant-growing provinces in the southern Peloponnese also continued to grow currants, but on a much smaller scale. Currants never regained the exalted status among Greek agricultural products that they enjoyed during the “golden age,” and a greater segment of the landscape was devoted to other crops such as figs and olives, but currants continued to be a part of the regional economies in the Peloponnese throughout the twentieth century.This chapter has demonstrated that an increase in foreign demand, technical and technological innovations, and land reform policies operated together to deepen the integration of Greek currant production with Western markets and transform normative agricultural practice from micro-ecological specialization to regional monoculture. The next chapter moves on to examine the spatial and ecological dimensions of this monoculture in the Peloponnese, i.e. how landscapes and settlement patterns were transformed to sustain intensive currant cultivation. In the middle of the nineteenth century, the spread of currant cultivation in the coastal plains of the Peloponnese transformed the regional economy and changed this pattern of settlement and migration, redefining the relationship between high villages and coastal hamlets. First, currant cultivation provided the impetus for lowland colonization. During the Little Ice Age climate, land reclamation was difficult and dangerous work. Under these conditions, there had to be a compelling reason to marshal the necessary labor and capital to drain lowland plains. The profitability of currants on the global market in the nineteenth century provided just such an incentive. The spike in foreign demand for Greek currants created the imperative and produced the means to undertake land reclamation and colonize lowland plains in the coastal Peloponnese in order to devote more land to currant cultivation. Moreover, around the middle of the nineteenth century, the Little Ice Age came to an end in the Mediterranean, making the reclamation of land from wetlands much easier .As a result, as Tabak argues, “During the course of the nineteenth century, but mostly gaining velocity from the 1850s, the low landscapes of the Inner Sea were steadily yet inexorably re-colonized.”In the late nineteenth century, there were “massive drainage projects” to turn lowland wetlands into arable land.The further incorporation of Greek agricultural production into global markets combined with a warming of the Mediterranean climate to permit large-scale, permanent colonization of the lowland plains. The dispersed, mountain settlement that characterized the seventeenth and eighteenth centuries in the Peloponnese gave way to large-scale, aggregated lowland settlements by the end of the nineteenth century.

One such strategy was poly cropping or intercropping, whereby farmers planted different crops on the same plot of land. This made the most productive use of a plot of land in all seasons and helped to ensure that even if adverse conditions caused one plot to under-perform the land would still be productive in another season. Olives, cereals, and pulses were harvested at different times, for example, and could be planted alongside one another.Figs mixed well with olives or with vines, so these could also be planted side-by-side.Poly cropping also occurred in household gardens, where cereals and a variety of vegetables were grown together.Another strategy was land fragmentation, meaning rural populations owned small plots of land in different places. This allowed them to spread their risk across different micro-ecologies, so adverse conditions in a given year on one of their holdings did not result in a total loss. Diversification also meant Greek populations were “pluriactive,” meaning they undertook activities beyond agricultural production. They were not simply farmers —they also kept livestock and they engaged in seasonal skilled and unskilled manual labor.Greeks also turned to other resources beyond those they produced themselves. Rural Greek populations knew that they could not depend on agricultural production alone to meet the needs of their subsistence, so they also relied on “marginal landscapes” in order to obtain other resources. In times when traditional sources of livelihood under-performed,fodder system for sale rural populations had to be ready to exploit other resources provided by different micro-ecologies.

Depending on the characteristics of the micro-ecology, there were different alternative sources of food. Lakes, rivers, and the sea could be turned to, for example, for fish, starfish, and eel. Other environments might provide tortoises, fowl, or game. Collecting wild greens, or horta, was a very common strategy throughout the Greek world.The other two imperatives, as mentioned above, were to store and to redistribute. Whenever a resource was produced in excess of the needs of the family at a given time, the surplus could either be stored or exchanged. It could be stored and thus saved for a time when other sources of production under-performed, and then it would buffer against the risk of subsistence failure in the future. Alternatively, it could be exchanged for other useful commodities that were necessary for survival.All of these strategies were developed to maximize the potential for meeting one’s family’s own subsistence needs every year. As such, we can say that subsistence was the norm—it was the goal that every peasant household aspired to achieve. In an ever-uncertain world, rural Greek populations sought to minimize their exposure to the risk that they might fail to marshal all the resources necessary for their survival. Scholarship on the historical ecology of the Mediterranean and on so-called traditional agricultural practice stumbles over the nineteenth century and collapses in the twentieth century. Horden and Purcell acknowledge that their model of the Mediterranean as a patchwork of shifting, interdependent micro-ecologies is difficult to apply in the modern period. They acknowledge that “Mediterranean history” ends sometime in the nineteenth or twentieth century, although they are uncertain when the shift occurred and what caused it.Grove and Rackham run into a similar problem.

They argue forcefully against what they call the “ruined landscape” theory—that the Mediterranean landscape was more lush and fertile in ancient times, and modern Mediterranean people degraded the land with their unscientific use of it. Their thesis is that human actions are not to blame for environmental changes in Mediterranean Europe. Mediterranean ecologies are resilient and constantly changing; fires and erosion are natural aspects of the Mediterranean and not a result of human misuse; “badlands” is a misnomer; and a lack of forest is not the same thing as deforestation. This argument certainly has its merits, but Grove and Rackham downplay the significant changes that have occurred since the nineteenth century. The literature on the historical ecology of the Mediterranean depicts a timeless, unchanging Mediterranean region from antiquity to the modern era. In this way, it replicates a pitfall of the related historical and anthropological literature on Mediterranean agricultural practice. If the Mediterranean ecology was unchanging, so, too, were human interactions with it. Scholars studying the ancient past have used ethnography of contemporary Greece to supplement literary sources and material culture. To better understand ancient farming practices, for example, they studied contemporary farming practices. John Campbell and Ernestine Friedl pioneered the field of ethnography of Greece, conducting field research in rural settings in Greece in the 1950s and recording their observations of rural Greek populations’ concepts of honor and shame, gender roles and family structure, and agricultural practices.There has been a tendency to treat these studies a historically as representing “traditional” Greek society, as if their descriptions of Greek village life could be applied equally to the 1950s, the 1850s or the fourth century BCE.

Susan Buck Sutton has called this approach “survivalism,” in which, “The nineteenth or twentieth century existence of a folk song, ceramic vessel, or farming technique similar to that of antiquity has been taken as proof of unbroken continuity.” This approach has been replicated in other disciplines, such as ethno-archaeology.It also fits well with Greek nationalist historiography, folklore studies, and Romanticism—endeavors for which an unbroken Greek cultural continuity from ancient times to the present is expedient. Ethnography has certainly been a useful way to fill in the gaps left by the limitations of other sources. Studying the ancient past through analogy to the present, however, has had its drawbacks, and more recently, this approach has come to be challenged. As Paul Halstead has argued, “Emphasis on relatively timeless constraints… of environment , technology and perhaps know-how has encouraged uncritical extrapolation to antiquity. Traditional practice was highly variable, however, and demonstrably shaped also by medium-term historical contingencies and cultural preferences and by short-term tactical decision-making.”It is now recognized that the Greek countryside and Mediterranean farming practices were contingent on a multitude of factors. As Halstead argues, there has been a tendency to overgeneralize Mediterranean farming practices, and there was, in fact, a great diversity of practices. Different regions in the Mediterranean imposed different material constraints—e.g. based on climate, terrain, and quality of soil—but many more factors also influenced farming practices. Individual factors also mattered a great deal, such as one farmer’s specific production goals, his strength and skill, the size of his plots, and the distance of his plots from his home. As Halstead writes, “Individual farmers often do things differently, because they are more or less industrious, conservative, proud, burdened with dependents to feed, or blessed with “hands” to help.” Based on these factors, individuals made different choices. Rich farmers with lots of land left more of their land fallow; poor farmers farmed every inch they could afford to.Finally, cultural factors need to be accounted for. Diversity in farming practice also results from different cultural “ways of doing.” There were many local customs that influenced farming practices, and not all of them were grounded in practical considerations.In sum, ethnography is a useful tool for postulating about farming practices in the past, but only when it is considered alongside other sources and when the contingencies of rural Mediterranean life are kept in focus. Among the larger contingencies that affected Mediterranean ecology and agriculture over the medium-term were economic, demographic, and climatic changes. As I examine next,fodder growing system the influence of these factors needs to be taken into consideration in order to understand the changes that occurred over the course of the nineteenth century. The dynamism of the Mediterranean countryside is well illustrated by an examination of long-term changes in settlement patterns, crop regimes, and climate. In the fifteenth and sixteenth centuries, the population of the Peloponnese—and of the Mediterranean basin in general—was concentrated in the lowland plains, which were the center of economic activity, and the main crops were cereals, especially wheat. Then, beginning in the middle of the sixteenth century and lasting until the middle of the nineteenth century, a new settlement regime became dominant as populations shifted away from low-lying plains and became more concentrated in the hillsides and mountains of the Mediterranean. Grain cultivation moved out of the Mediterranean, and the Mediterranean returned to the cultivation of its “civilizational crops,” i.e. vines and olives.The shift of the economic and demographic center of the Mediterranean from its low lying plains to its hills and mountains occurred at the interface of two larger processes. The first was a drop in the annual average temperature, often referred to as the Little Ice Age.

Estimates vary, but this Little Ice Age lasted roughly from the middle of the sixteenth century to the middle of the nineteenth century in the Mediterranean. The Little Ice Age was a period of “several phases of cool summers and cold, snowy winters.”During this period, there were also several clusters of extreme weather events in Mediterranean Europe, including floods and out-of-season rain, droughts, and especially cold winters—the worst decades were the 1540s, the 1560s to the 1640s, the 1680s to the 1710s, and the 1810s. These weather events often resulted in failed harvests, frequent famines in much of Europe, and favorable conditions for certain diseases, such as malaria and plague. The cause of the Little Ice Age is unknown. Alpine glaciers advanced at times during this period due to successive heavy snowfalls followed by cool, late springs—this could explain extreme weather events in the Alpine Mediterranean, but not in the southern Mediterranean. Other possible explanations include volcanic eruptions, sunspot minima, a shift in the anticyclonic belt of the Northern Hemisphere similar to the one that caused the Medieval Warm Period that preceded the Little Ice Age, or some combination of these factors. Whatever the cause, this change in the climate of Europe and the Mediterranean made the cultivation of lowland plains more difficult and less predictable. In Mediterranean Europe, the colder average temperature meant a shorter growing season in the summer and a wetter climate overall. Due to increased fluvial discharge, the best croplands in the low-lying plains were waterlogged for a longer segment of the year. As Faruk Tabak has written, the lowland plains “were largely deserted and taken over by swamps, wetlands, and reeds—not to mention the fauna that thrived in such environments: the mosquito, snakes, storks, and lizards.”During the Little Ice Age, making wetlands suitable for habitation and cultivation was an expensive, labor intensive task. Drainage works needed constant upkeep, and they could be swiftly undone by an unexpected deluge. Furthermore, the risk of malaria made it a dangerous endeavor, and land reclamation needed to be done on a sufficiently large scale to eliminate the risk of malaria from nearby fields. This was the world that Braudel described in The Mediterranean and the Mediterranean World in the Age of Phillip II in which he wrote, “To colonize a plain often means to die there.”With the beginning of the Little Ice Age, permanent settlements moved from lowlands to highlands, and temporary settlements , “mushroomed throughout the basin.”The second factor that caused population to become more concentrated in upland areas was the transplantation of American crops to Europe and of old world crops to the Americas—a process often referred to as “the Columbian exchange.”In the seventeenth century, landand labor-intensive “oriental” crops, especially cotton and sugar, moved out of the Mediterranean and to the Americas, where there was plenty of land to exhaust and slave labor to exploit. From the 1650s on, sugar production shifted from the Mediterranean to the Atlantic , and sugar production was much greater there. In the fifteenth century, Cyprus exported a few hundred tons annually; in the seventeenth century, Jamaica exported 72,000 tons annually.In addition, grain production moved out of the Mediterranean and was relocated to large estates in Eastern and Central Europe, also with coerced labor. In the sixteenth century Mediterranean, the grain trade was 100,000 to 200,000 tons. In the seventeenth-century Baltic, the grain trade was 600,000 tons.Meanwhile, in the Mediterranean, American crops were being introduced to replace sugar, cotton, and grains. The American crops that were introduced—e.g. tobacco, maize, and beans—could be grown at higher altitudes in the Americas, and they similarly thrived in the highlands of the Mediterranean basin.As populations were forced to relocate to higher altitudes by the inhospitable conditions of the Little Ice Age, the crops that justified lowland settlement in the first place disappeared from the basin, and upward relocation was facilitated by the availability of new crops that thrived at higher altitudes.

The Chavista governor of Portuguesa Antonio Muñoz reportedly stopped land invasions and maintained good relationships with grower associations in the state . Under Muñoz’s successor, Wilmar Castro, growers and state officials reported that land invasions by peasants and state intervention on estates increased . In general, however, producer associations stated that they maintained non-conflictive working relations with state institutions . ASOPORTUGUESA, for example, collaborated on a number of seed and crop research programs with the National Institute of Agricultural Research throughout the Chavista period. More importantly, broader agro-food policy continued to evolve in the Chavista period in a way that tended to shield a large number of commercial growers from expropriation. As the government became increasingly concerned about food availability it largely avoided intervention in commercial cereal or oilseeds producers. INTI officials in Portuguesa stated that as a matter of policy, productive farms were not targets for redistribution in order to ensure agricultural production . Even some activist peasants in the reform sector articulated a similar position that if land was in production campesinos considered it off the table for occupation. In Yaracuy state, for example, where conflict over land has been particularly pointed and conflictive, one peasant leader who himself had helped to occupy an estate said large landowners who were productive were ‘welcome’ . Through the Chavista period,dutch bucket hydroponic state agro-food policy became increasingly focused on maintaining the productive base for domestic provisioning and distribution of foodstuffs and less on the breaking up of historic land relations in rural areas.

Where the state has accelerated and widened its intervention in the agriculture sector has been primarily in marketing and distribution components of the food system or in particular crops such as coffee. Figure 20 shows acceleration of expropriation in the food sector beginning in 2009. These expropriations, however, can be read as part of a broader state strategy to ensure agricultural production and food distribution chains, rather than attempts to dismantle landholder power. The Venezuelan government, for example, nationalized major coffee companies Fama de America and Café Madrid in 2009 as part of a strategy to increase control over the distribution and processing of coffee and ensure its availability in state food distribution networks. Expropriations of the supermarket chains Éxito and Cada, and of agro-chemical company AgroIsleña, targeted not landowners, but up and downstream components of the agro-food system to support production at the farm level of all sectors of agriculture and, again, food availability at the market level. In addition, since 2003 the Chavista government sought strategic, unofficial ‘alliances’ with business interests that were considered important to the nation’s economic development . After the 2002-2003 oil strike promoted by FEDECAMARAS, the Chávez government declared it would favor non-striking business interests by providing them with access to dollars for imports at preferential rates Such concessions demonstrate a strategy of reconciliation between the capitalist sectors and the state in order to ensure macroeconomic stability. In Portuguesa, patterns of land occupation by peasants and government intervention in estates by and large circumvented the major cereal and oilseeds producers that formed the backbone of the state’s agricultural economy.

Growers did state, however, that as a preventative measure to land occupation by peasants they often planted ‘holding crops’ on land that were not harvested due to their general unprofitability—such as beans . An INTI representative in Portuguesa stated that when land occupations on estates did occur, the local INTI office declared them as illegitimate and withheld support from the occupiers including inspections and any granting of official rights to remain on the land .Where there was significant state intervention in private estates it was primarily related to continued conflict over timber plantations owned by the transnational packaging corporation Smurfit and in areas devoted principally to extensive cattle ranching. Most peasant occupations in Portuguesa during this study’s field periods were concentrated in these tree farms near the agro-industrial core and in cattle ranching areas that were located more on the state’s agrarian periphery. The peripheral lands—such as in the municipality of Guanarito—were relatively distant from major infrastructure, had inferior soils to those in the agribusiness core, were less likely to have mechanized production systems, and were less integrated into agro-food processing chains. Parcels in Guanarito were more likely to be perceived as idle and, thus, scenes of peasant occupation and state intervention. The Dos Caminos estate seized by INTI—one of the cases cited by local growers as indicative of government pressure on productive, private land in the state—was primarily involved in cattle and dairy operations, not cereal or oilseeds production . A land occupation at the San Rafael de Onote estate was ruled illegal in 2012 on the grounds that the estate was productive due to its maize and porcine production . That same year the Supreme Court reversed an initial ruling against the owners of the Palo Gordo estate after it was declared to be productive.

These cases reinforce the argument that cereal producers were not subject to significant land expropriation pressures. In a general policy climate of ensuring staple foods, the agro-industrial core of cereal and oilseeds producers appeared to be under relatively little threat of land seizure from the government. This is not to disregard the role of peasant pressure in influencing targets of government intervention in land and the shape and pace of land redistribution28 but rather to suggest that the major thrust of land redistribution has not been directed at sectors of commercial producers even in areas where they control a majority of the best and most productive lands. Landowners have used violence and intimidation in the reform period to fight against the agrarian reform. According to peasant groups, between 2003 and 2011, an estimated 256 campesinos were killed , likely by hired gunmen. According to campesino groups, no one has been convicted of any of the killings . That no landowner has been convicted of a peasant murder demonstrates the persistence of latifundio influence both regionally and in the judicial system where the deaths are investigated and prosecuted. This is despite nominal control of the judiciary by the Chavista political party, PSUV. Peasant groups have, thus, had to contend with the threat of violence when organizing for land. Land reform-related violence against peasants—as can be seen in Table 8—has largely been concentrated in four or five states within Venezuela. Portuguesa ranks as the state with the 4th highest number of peasant murders. Relevant to this dissertation’s argument, deaths were not common in the main agroindustrial areas of Portuguesa. The bulk of killings in Portuguesa occurred in Guanare and Guanarito municipalities .

Guanarito, as discussed, is an area home to relatively extensive dairy farmers that held more idle land than other areas where cereal and oilseeds production is integrated into agro-industrial chains. Peasant occupations that occurred primarily in Guanarito and nearby geographically and economically isolated areas engendered more violent responses. That commercial farmers in the agro-industrial corridor faced less occupation pressure underscores their relatively ‘safer’ position in terms of land redistribution pressures. Landed interests can also leverage their position as employers in land conflicts to blunt and fragment peasant pressure for state intervention. The case of Smurfit Kappa is an instructive example. Beginning in the 1980s, Smurfit began toacquire and operate tree plantations eventually totaling 31,000 hectares of Caribbean Pine and Eucalyptus in Portuguesa and Lara states . Smurfit’s expansion precipitated conflicts with peasants as farmers lost land or retained only limited access to areas that were surrounded by newly fenced tree plantations. In addition, there were a series of conflicts between managers and workers over working conditions and benefits. Conflict between Smurfit and peasants has continued throughout the Chavista era and has been heightened by the redistributive possibilities represented by the 2001 Land Law and increasing petitions for land and peasant occupations of some tree plantation areas. Relations between Smurfit, the state,dutch buckets system and peasant groups that this conflict has engendered is explored more thoroughly in the following chapter. The relevant point at this juncture is the dual strategy Smurfit has taken in order to diminish historical and resurgent peasant pressure. On one hand Smurfit has ceded certain parcels that INTI has classified as apt for crop production to the state in exchange for retaining ownership of other plantation areas.

This includes pre-Chavista negotiation where Smurfit gave up the 2,000 ha estate La Productora—which later became a co-managed Unit of Socialist Production in 2008—as well as more recent acquiescing to INTI inspections and redistribution of land to agrarian reform groups under the understanding Smurfit would be able harvest the timber before ceding control as well as receive indemnification from the state . On the other hand, over time Smurfit improved pay and benefits for workers, including providing scholarships to families of estate employees, which have became important subsidies for local households . Much of these benefits were won by workers after violent labor struggles that predate the Chavista era. These historical gains in labor conditions have contributed to Smurfit workers opposing peasant groups occupying Smurfit plantation areas, although both groups actively identify as government supporters. In 2012, I saw signs placed by Smurfit’s workers’ union along Portuguesa’s main highway reading “We are not exploited” and “We are also the revolution” to counter arguments that the seizure of Smurfit’s plantations would address exploitative labor relations as part of the Chavista socialist revolution. Smurfit workers saw peasant calls for land as threatening their relatively well-paid jobs whose benefits they obtained via hard-fought labor struggles. As part of the agrarian reform union members had been offered land they currently worked on as Smurfit employees, but stated that as laborers they received greater and more secure benefits than they could obtain as farmers on recovered plantation land . Workers cited an impression of general improductivity of agrarian reform settlements in the area, as well as the unreliability of state institutions that provided support to settlements . In response to threats of nationalization, the union negotiated its own proposal with Smurfit to cede certain parcels to the state in exchange for retention of core lands and then delivered the proposal itself to INTI officials . Essentially, the Chavista workers’ union negotiated with the state on Smurfit’s behest in order to constrain peasant land claims. This effectively fragmented the Chavista base’s stated position on land reform in the area. Reading dynamics between the state and the commercial sector as uniformly antagonistic and combative glosses over a series of more ambivalent relations. Violence against peasants, although significant, has largely been isolated to a relatively few areas of historical land conflict where peasant organizations have pushed for occupation of estates. State expropriation of land holdings has primarily been limited to areas of extensive cattle ranching rather than commercial commodity crop production . And while expropriations of supermarkets and large cattle estates have been featured in media headlines, these nationalizations have often targeted foreign, not domestic capital— the supermarket chain Éxito, for example, was owned by a French company—and land seizures are often negotiated with landowners, leaving large parts of estates, most likely the most productive and profitable areas, with the previous owners. In addition, commercial cereal producers in Portuguesa have faced relatively little risk of land redistribution even in areas that are highly Chavista. State intervention and peasant pressure in Portuguesa has instead been concentrated in cattle ranching areas on the peripheries of the state or in areas with foreign-owned tree plantations. As issues of food prices and availability in supermarkets serve as salient electoral weaknesses of the ruling party, combative rhetoric and threats of intervention of food processors take place in a wider policy context that seeks to incentivize production in all sectors of agriculture. I now move to discuss how certain Chavista agro-food policies contribute to accumulation in the commercial agriculture sector, even as state rhetoric maintains a pro-poor and pro-peasant character. To support agricultural production, the Chavista government in 2001 reasserted lending requirements of commercial banks to the agriculture sector. The Ministry of Agriculture and the Ministry of Finance are tasked with setting the percentage that commercial banks must lend to agriculture each year or face sanction. The amount required is set by the central government through the Committee for Monitoring the Agrarian Portfolio . The mandated percentage fluctuates from month to month but in general there is a 20-25% target, with a ceiling of 30% .Commercial banks have largely failed to meet the mandated lending targets .

Conventional growers can use a pesticide spray on the trap crops, but that’s not an option for organic growers. However, tractor-mounted vacuum units known as “bug vacs” are one of the tools available for organic systems. “I worked on research of the original proprietary bug vacs for the strawberry industry back in the late 1980s,” recalls Swezey. “But back then we were using more of a shotgun approach, vacuuming all of the crop fields, which in a way was equivalent to using a pesticide because it affected all the insects in the fields—both pests and beneficials. This seemed to me to be as non-selective as an insecticide application.” Swezey and Larry Eddings, president of Pacific Gold Farms, speculated that by concentrating the pests in one place, an effective trap crop could be managed with bug vacs, thus eliminating the need for growers to run vacuum units across their entire strawberry plantings. If effective, the approach would not only decrease WTPB damage to the strawberry crop, but would save time and energy by cutting down on the area that needed to be vacuumed, and would conserve populations of beneficial insects in the crops. In 2002 and 2003 the Center research team of Swezey and research assistants Janet Bryer and Diego Nieto worked with Eddings and his staff at a Pacific Gold Farms site in Prunedale to test their theory. Grants from the Organic Farming Research Foundation and the US Department of Agriculture’s Western Sustainable Agriculture Research and Education program supported the work.Using a hand-held suction device, Bryer and Nieto collected insect samples in the trap crop plantings weekly beginning in January 2003.

The samples were then frozen and insects were identified and counted under a dissecting microscope. They also monitored insects in row 1 of the strawberry plantings using the same technique. The radish trap crop flowered from February through the end of May, when it was removed. The alfalfa trap crop began flowering in mid April and continued to flower through September. On April 11,strawberry gutter system collaborators from Pacific Gold Farm began vacuuming the beds and trap crops with a tractor-mounted unit that includes three rectangular vacuum collectors that generate a suction of approximately 28 miles/hour . Operators drove the tractor at 1.2 miles per hour when vacuuming the rows, passing over the strawberry canopy at canopy height once a week, and over the alfalfa trap crop row two days a week each week through the season . In mid April, in addition to monitoring the trap crops, Bryer and Nieto began monitoring insects in strawberry rows 1, 2, 4, 8, and 16. They also examined berries from four randomly selected clusters of four strawberry plants ; each week, developing berries that showed signs of distinct WTPB damage were counted and removed, while undamaged berries were counted once they matured. Adult WTPB were first found in the radish trap crop vegetation on January 7, and in the alfalfa trap crop in mid April, when it began to flower. Based on a heat unit accumulation model1 initiated when the first adult was found on January 7, the researchers predicted that a second-generation adult would not mature until July 19 at the earliest; therefore, the WTPB adults found any time before this date had migrated to the crop . This result suggests that there is a six-month period during which migrant WTPB adults are attracted to trap crop vegetation at the edge of strawberry fields.

Figure 1 shows total accumulation of WTPB in the unvacuumed trap crop treatments and the adjacent row of strawberries. Significantly more WTPB were found in the alfalfa than in either the radish trap crop or row 1 of strawberries. For seven weeks in April and May, when both the radish and alfalfa trap crops attracted adult WTPB or nymphs hatched in the vegetation, and when the grower was conducting commercial field vacuuming treatments, alfalfa attracted or retained over 7 times more WTPB than the radish trap crop. Although it flowers and matures somewhat later in the spring, alfalfa was a significantly more effective trap crop for WTPB. This result has management implications for central coast growers. “We’d experimented with a variety of trap crops through the years, including radish, mustard, alyssum, and other flowering annuals and perennials,” says Swezey. “But we’ve found that the radish and some of the other crops can become difficult to deal with once they begin to die back in the summer. Given the results of this study, which show that alfalfa is far more effective at attracting WTPB, we are focusing on alfalfa.” Because heavy spring rains often continue through April, tractor-mounted vacuum management of a trap crop can only begin in early May, when muddy conditions have diminished. This is an optimum time to begin alfalfa trap crop vacuuming. Pattern of WTPB Numbers and Strawberry Damage by Treatment and Row In June, weekly, tractor-mounted vacuuming of the alfalfa trap crop reduced total WTPB by 70% compared to the unvacuumed trap crop . The vacuumed trap crop treatment had the same accumulated WTPB as either the whole-field vacuuming treatment or the untreated control. In contrast, the unvacuumed trap crop consistently accumulated higher numbers of WTPB in strawberry rows 1, 2, 4, and 8. There were no differences among treatments at row 16, indicating that the trap crop’s effect on WTPB numbers ended somewhere between rows 8 and 16. Why the total WTPB numbers in the untreated control were consistently low in June is not clear. It’s possible that whole-field vacuuming in the commercial fields surrounding this experiment lowered the general level of WTPB in the small test plots. Movement or “sinking” of WTPB to nearby trap crops could also explain the low numbers in the control plots.

As shown in figure 3 , the vacuumed trap crop treatment had a significantly lower percentage of damaged strawberries than either the whole field vacuuming or the untreated control . Blueberries offer small-scale growers a potentially profitable “niche” crop that can be developed as a U-pick operation or incorporated into other marketing activities. Although the plants need several years to get established and require careful soil preparation and fertility management, a successful blueberry crop can generate $30,000 to $50,000 per acre . To learn more about the best-performing varietal options for organic growers on California’s central coast, the Center initiated a variety trial of mostly low-chill, high bush blueberries at the UCSC Farm in the fall of 2003. This project is being conducted in collaboration with Aziz Baameur, Small Farm Program Advisor for Santa Clara County’s UC Cooperative Extension office, and Mark Bolda, UCCE’s central coast Strawberry and Caneberry Advisor. Blueberries need well-drained, acidic soil in order to thrive. In November 2003, UCSC Farm manager Jim Leap applied sulfur to the trial site at a rate of approximately 2,000 pounds per acre as well as 3–4 inches of acidic mulch, then created raised beds for the plants. With the help of second-year apprentices Aaron Blyth, Carissa Chiniaeff, Allegra Foley, Estrella Phegan, Ratoya Pilgrim, and Matthew Sutton, the research team planted out 17 varieties of blueberries in January 2004. The trial includes 4 replicates of each variety planted on 3-foot plant in-row spacing with 5 feet between rows. Peat was applied in the planting hole to further lower the pH. Varieties being tested are: Biloxi, Bluecrop, Duke, Emerald, Jewel, Jubilee, Misty, Oneal, Ozarkblue, Millennia, Santa Fe, Sapphire, Sharpblue, Southern Belle, Southmoon, Star, and Windsor. After planting, the beds were mulched with several more inches of acidic bark, and drip tape was laid on top of the mulch. Plants are irrigated weekly with the drip tape, and during each irrigation vinegar is injected into the irrigation water to maintain a low pH. Phytamin, a liquid nitrogen fertilizer, is being applied through the drip lines monthly during the summer to maintain adequate nitrogen levels and get the plants off to a strong start. Over the next several years, the research group will evaluate a variety of factors,grow strawberry in containers including overall plant vigor, disease and pest resistance, and eventually, harvest dates, fruit taste and quality, and fruit production. Although the first harvest is still 12 to 18 months away, Leap is excited about the trial. “Blueberries offer a great marketing opportunity for small scale organic growers,” he says, adding that, “this project has also created great opportunities for interactions between the Center and our local UCCE advisors.” A blueberry field day organized by the Center, UCCE, and the Community Alliance with Family Farmers was held in early June, bringing farmers and gardeners to the UCSC Farm for a look at the new plantings. Speakers included Baameur, Leap, and Bolda, as well as UCCE researchers Richard Smith, who discussed organic weed management, and Laura Tourte, who talked about blueberry economics and marketing.As an environmental scientist, Center faculty affiliate Deborah Letourneau believes policy decisions should be based on the best information available at the time. That’s why she’s trying to fill an information gap with her latest research on genetically modified plants.

As insect-resistance is bred into major crops, Letourneau wonders how those crops’ wild relatives might be affected if they pick up the new traits. “There’s been a lot of research on crop-to-crop movement,” said Letourneau, referring to the contamination of organic corn grown adjacent to genetically modified corn. “But we don’t know that much about the biology of wild crop relatives. If genes transferred, would it make them more weedy, more hardy, more invasive?” To address these questions, Letourneau, a professor of environmental studies at UCSC, along with doctoral candidate Joy Hagen and Ingrid Parker, an associate professor of biology, have begun a three-year study to see what the consequences would be if GM genes transferred from Brassica plants through cross-pollination to their wild relatives. Plants in the Brassica, or cole, family include many vegetable crops, such as broccoli, Brussels sprouts, cabbage, cauliflower, and kohlrabi, as well as common weeds like wild radish and wild mustard. “Weed problems translate into economic problems for farmers,” said Letourneau, noting that 75 percent of cole crop production in the United States is concentrated on the Central Coast of California. Stubborn weeds require more herbicide applications, with accompanying higher labor costs and environmental impacts, she said, adding that highly invasive weeds can threaten native species on non-agricultural lands, too. Letourneau is a leading authority on the genetic modi- fication of plants. A member of the National Academy of Sciences’ 12-member panel investigating the environmental consequences of GM plants, she also coedited the 2002 book, Genetically Engineered Organisms: Assessing Environmental and Human Health Effects. Parker’s background is in applying mathematical models to ecological risk assessment for GM crops. More than 25 percent of corn grown in the United States has been genetically engineered to contain the toxin of the Bacillus thuringiensis soil bacterium, which disrupts the digestive system of a caterpillar. Transgenic cotton and potatoes also produce Bt toxin. Little is known about the role Bt-susceptible herbivores, including caterpillars, play in regulating the health and spread of wild crop relatives. In their research project, Letourneau and Hagen are protecting wild relatives from caterpillar damage to see what could happen if modified genes moved from Brassica crops to their wild relatives. The simulation is necessary because the research is being conducted in open fields—not inside greenhouses—where risks of contamination by GM plants would be high, said Letourneau. To mimic an effect of gene transfer, the UCSC researchers are spraying Bt on wild radish and wild mustard growing adjacent to commercial cole crops, and they will use models to evaluate the subsequent fitness, weediness, and invasiveness of the weedy relatives, said Letourneau. “We can’t use real transgenic crops, but we wanted to conduct this work where wild relatives live side-by-side with commercial crops,” said Letourneau. Research sites include the Center’s on-campus Farm and agricultural parcels adjacent to natural ecosystems from Wilder State Park to Elkhorn Slough Reserve. Genetic links between crops and weeds are remarkably common, and cole crops are no exception, noted Parker. “In the past, the evolution of many weeds has been driven by genes coming from crops,” she said. “Now those genes will be specially engineered by humans.” Research on consequences for wild relatives is overdue, said Letourneau, noting that field-testing of GM cole crops for California has been under way since 1999. “This kind of research is important now, during the process of risk assessment, to know whether new modified crops should be deregulated or not,” she said. “There are a lot of Bt crops in the pipeline.

The sediment perching phenomenon, in our view, is similar to the decision making proposed by Arrow et al: one waits until the stock is down to a certain value before replenishing the stock.Literature has focussed on the debate of whether a dam should have “design life” or whether it should be run sustainably by using life cycle management strategy. Intergenerational equity requires that a dam either be run sustainably or the generation that benefit from the dam pay for its decomissioning cost . Palmieri et al discussed about a method to generate such fund in a reservoir in China. In addition to these studies, Keohane et al proposed a SFQ model which they suggested could be used in the context of reservoir management. In their model, stock and flow both must be controlled to promote the quality, which in the context of reservoir management problems requires the control of both sediment flow and sediment stock to maintain the quality of the reservoir and reservoir products.Their result implied that if the dam operator has the choice of both sediment removal and restoration, then the threshold that triggers restoration in the absence of choice regarding sediment removal would be lower than the case in which planner has the option to remove sediment. On the other hand, the feasibility of restoration will reduce the optimal sedimentation removal at each level. The author seem to treat restoration as if the asset being restored is renewable. However, we believe that is clearly not the case in reservoir management. However, the issue is similar to much studied machine replacement problem in finance and economics. The major study in the literature was due to Rust,grow bucket who studied the decision of an administrator making decision on repair or replacement of GMC bus engines.

A dam administrator is in a way similar to Harold Zurcher, the bus administrator: making a decision on repair or decomissioning, but most likely, without the option of replacement. Furthermore, with dam, the concept of sustainably running it is more important, where as with the bus, it is not even considered. This class of technique include the investment in erosion control upstream so that the river doesn’t carry a lot of sediment into the reservoir. This method is mainly focussed in rehabilitation of degraded soil and watershed upstream. Literature in sedimentation management emphasize that such management strategies be carried out with the help of landowners upstream as their noncooperation result in the failure of erosion control programs. Sediment management and erosion control techniques may use methods ranging from basic land use changes to the complicated high fixed cost structural methods such as construction of terraces, diversion channels, grassed waterways, check dams. Nonstructural methods include agronomic measures which rely on the regenerative properties of vegetables. Other methods in use include operational measures such as scheduling construction to minimize the area of exposed soil. Land use changes doesn’t involve fixed cost, and may not result in reduced sedimentation yield immediately downstream. Faulkner and McIntyre reported that there were no change in sediment yield even 20 years after the transition to less erosive land use. There are several basic agricultural engineering techniques in erosion control for a detailed study on it. In the United States, Best Management Practices are recommended for erosion control. From the economic point of view, these methods can be divided into two classes: structural methods are fixed cost method with low annual maintance cost and nonstructural methods have no fixed cost, but have relatively higher annual maintanance cost. They also differ in their effcacy: it is recognized that the nonstructural methods can never lead to zero sedimentation yield downstream. Erosion control is also topography dependent.

In countries like Nepal, which is situated in the tectonically active Himalayas, erosion control in the watershed is not considered technically feasible in several possible reservoir sites. This is the same case in Tarbela, the reservoir about which we study in detail later. Excavation are costly options and most of the time, they are the only options once sediments are firmly deposited in the reservoir. Excavation option often depend on sediment volume, grain size, geometry of deposit, available disposal and reuse options and water level and environmental criterion. Dredging is an operation in which sediment is lifted from the bottom of the surface of a waterbody and is deposited elsewhere. In the United States, 500Mm3 sediment is dredged every year. Dry excavation involves completely emptying the reservoir, desiccating the surface and deposits and using earth moving equipment to remove the silt from the surface. Hydraulic excavation will require dewatering dredge slurry after it has been removed from the water surface, so that it can be removed in conventional hauling equipments to dump elsewhere. In small ponds in the united states, there have been some use of explosives to excavate sediments, but such use is rare among the large ponds. Dredging as a long term strategy for reservoir management is possible only if a good dumping site can be found. Although in many mountainous regions, the river downstream is considered the natural target for dumping dredged materials, such dumping is considered environmentally undesirable. There is a related method called Hydrosuction removal system that uses the hydrostatic head at the dam to provide energy for sediment removal. HSRS is of interest because there has been one major economic study of this method in detail. This method is similar to dredging, but it applies the hydraulic head available at the dam as the energy for dredging and is considered cheaper than dredging.

HSRS consists of a barge that controls the flow in the suction and discharge pipe and can be used to move the suction end of the pipe around. The pipe’s upstream end is located at the sediment level in the reservoir and the downstream end is draped over the dam to discharge sediment to downstream. Because of this, its applicability is limited to shorter reservoir. This method is normally considered energy conserving,and environmentally friendly. Public’s perception of dam as a clean source of energy has undergone some changes recently. In particular, the role of a dam as an emitter of green house gas has been asserted by researchers such as Ruud et al and Duchemin et al . Duchemin et al studied methane and carbon dioxide emission in two hydroelectric reservoirs in northern Quebec for two years and found “above average emission fluxes”. Their result showed the emission flux to be five to eight times less than what Ruud et al found out. Though Duchemin et al found the emission was on a much smaller scale than conventional thermal power plants equivalent amounts of energy, studies done in Brazil’s Balbina reservoir , Irion et al showed that the reservoir produces more greenhouse gas than coal fired equivalent due to the vegetation inundated by the reservoir. Such results have made it diffcult for large reservoirs to qualify for carbon credit in carbon markets, even though the small hydropower with no forest inundation often qualify for it. If large dams are sources of substantial emission, then their actual cost to the society is likely to be uncertain for long,dutch bucket for tomatoes since there is significant uncertainty related to the damage function: damage to the society due to GHG induced increase in temperature. Hence the dam operator may know the cost of decomission at any moment, but the cost in the future is uncertain. This calls for the modification in assumption of Palmieri et al that the salvage value of the dam is fixed and constant. This also provides motivation to learn how sediment removal rate will be changed under such scenario. There are two main reasons why a reservoir is decomissioned: the owners may find it economically infeasible or the regulatory agencies may demand that the reservoir is decomissioned. In the United States, Federal Energy Regulatory Commission stated in its statement that it has the right to decomission a project when considering its relicensing request. When a dam is decommissioned, there are three major issues: what should be done regarding the dam? what should be done regarding the sediment deposited in reservoir? How should environmental restoration be carried out? The dam could be left as it is, partially breached or completely removed.

The sediments could be left as it is if dam is left as it is. The other choices regarding sediment management are to allow natural erosion, construction of a channel through the deposits while leaving off chanel sediment as it is, and removal by mechanical excavation or hydraulic dredging.Some agencies may demand that the dam operator restore early fluvial condition. In such case, the dam operator may incur extra costs, apart from sediment management and infrastructure removal.It is reasonable to assume that the change in the cost related to and are relatively known and deterministic, but the change in the salvage cost related to will be uncertain. Such uncertainties also point to the need to study dams in stochastic settings. As we noted earlier, global warming implies higher erosion. Higher erosion increases the sedimentation arrival rate at the reservoir and this leads to the change in the value of reservoir. Our model shows that increase in the sedimentation rate decreases the value of the reservoir, in particular at the lower storage level. This is because increased sedimentation implies increased cost of removal of sediment.The cost of removing the storage is high at the lower level and therefore, increase in sediment is likely to decrease the value of the reservoir. Moreover, as Figure shows, the increased sediment arrival implies increased sediment removal at all level where sediment removal is optimal. Discount rate features in our model in two important ways. The first is that discount rate has its traditional meaning regarding the patience of the society.For example, it is expected that higher discount rate encourages individuals or society to consume more today. It also enters our model in a different way . If the society faces uncertainty about the future of the reservoir, its decision making , under some assumption about the nature of such risk, is akin to increased discount rate. Figure implies that increased discount rate increases sedimentation removal at the lower level water storage. Impatience in this case doesn’t mean the policymaker will lessen the sedimentation removal. At all levels of water storage, increased impatience also increases the value of reservoir by a small amount. It is possible that uncertainty about the future makes people value the reservoir more. Both of these results imply that increased discount rate will not lead to social planner scrambling to abandon the reservoir by decreasing sedimentation removal. The impact of increase in price is also reflected in the increase of value of the reservoir in the entire domain except at the end points. Figure shows this expected result. Figure shows that the impact of increase in implicit price on sediment removal. Higher price led to the increased sediment removal, as water is now more valuable. The results above were all conditional upon several things: that the cost functions were of a particular form, that the social planner was risk neutral and that the sedimentation arrival rate followed a certain temporal path. The debates underlying large reservoirs are often hard to address particularly because in most of the cases most of these functions are also less understood. In deed, the reservoir management literature is only recently trying to understand various aspects of reservoir managements. For example, there are very few works that explain the role of different factors in contributing erosion in the reservoir.Pacific Southwest Interagency Committeeís watershed inventory method is often used in predicting sediment yield from watershed condition but it is a very speculative method. Similarly, few literature exists that explain the precise nature of cost function for removing sediments from the reservoir. As WCD report made clear, the systematic study of reservoirs have recently begun, and hence there is still a lot of scope for identification of different parts of a reservoirís economic system to make a precise and integrated statement about the system. Sustainability of dam is a topic of interest when talking about the consumption of natural resources.

Since we can estimate the relative percentages of these unit types across our three scenarios, we could then calculate approximate energy use for the new households in each scenario. We adjusted for assumed trends in household energy use and efficiency within each scenario, using the 1985 to 2005 statewide reduction of approximately 15 percent per household as a baseline for the A2 scenario .Under the A2 story line development is dispersed in and around existing urban areas . The new development footprint is highest at over 14,000 acres. The urbanization pattern reflects an urban sprawl pattern of growth that is typical today and likely to continue into the future unless there are changes to planning policies and a reduction in population growth. Dunnigan, an area of the county where growth is currently being proposed, receives new development under A2. The B1 story line has urbanization that is more attracted to existing urban features. Under B1, growth is less dispersed and more concentrated in and around the urban sphere of influence; new development takes up over six thousand acres . Due to the AB32+ story line’s strict infill planning policy and mask on non‐urban lands, almost all new development occurs within existing city boundaries . No development occurs in West Sacramento,hydroponic nft channel which is within the one‐hundred‐year floodplain and was thus masked from development within this scenario.

The urbanization policy reflected in the UPlan variables and the amount of population growth under each story line creates a unique pattern and footprint of development. AB32+ is by far the most compact, has the smallest urban footprint, and consumes the least amount of crop‐ and irrigated land, as well as non‐irrigated grazed lands. The story lines vary in the amount and type of new land uses . Under the A2 story line, for example, residential low, commercial low, and residential very low categories take up 9,081 , 2,687 , and 1,441 acres , respectively, by 2050. In this story line, residential medium‐density development takes up a larger percentage of newly developed land area, and in the AB32+ story line, most development is either residential medium or residential high density. One of the most striking findings is just how little land is required to house future populations at these higher densities. The B1 and AB32+ scenarios require 44 percent and 7 percent of the urbanized land of the A2 scenario respectively. Even holding population increase constant at B1 levels, these scenarios use 63 percent and 38 percent of the land of the A2 scenario; most or all of it within existing urban areas.A detailed GIS map of cropland in Yolo County for 2008 was overlaid onto UPlan results to show the crop acreage lost to urban growth under each scenario. The acreages of crops lost to development varied greatly among the three story lines, ranging from 10,562 in A2 to 3,363 in B1 to 23 in AB32+ . These results reflect the lower total population growth and stricter urbanization policies in the B1 and AB32+ story lines. Alfalfa, processing tomatoes, and pasture lands had the highest acreage loss under the A2 story line. The same three crops were most affected under the B1 story line but impacts were higher on processing tomatoes than alfalfa. In the A2 story line, the new development footprint resulted in about 3 percent of irrigated crop land being lost in the county, while in the B1 story line 1 percent was lost, and for AB32+, only 0.04 percent was lost.

Floodplains were more likely to support urbanization under the A2 story line compared to B1 . The B1 story line assumed much more discouragement to wetland and floodplain urbanization, both for protection of constructed units, and for environmental benefits. Urbanization on wetlands under frequent inundation was unlikely in either scenario, partly because flooding risk discourages building construction. Vernal pools, a landform that supports many endemic species, were more vulnerable to urbanization under the A2 story line . The wetland area is currently increasing in Yolo County due to creation of freshwater wetlands for flood conveyance for the high flows from several northern California waterways to the Sacramento‐San Joaquin River Delta, and for wildlife habitat . Wetland conversion can indeed be a “Best Management Practice” in some circumstances, and there can be additional ecosystem services provided by specific management of wetlands. But the loss of agricultural land is still a significant concern for the viability of agricultural operations, markets, and related industries in the county. The Williamson Act is a California law that reduces property taxes to owners of farmland and open‐space land in exchange for a ten‐year agreement that the land will not be developed. Under the A2 story line, farmers would be more likely release their holdings in the Williamson Act. The A2 outcome was nearly four times greater losses compared to B1, whereas AB32+ assumed no change in Williamson Act . Not surprisingly, transportation‐related GHG emissions from new development vary greatly across the three story lines . As noted above, this difference is a function of assumptions about reduced driving by residents of infill development compared with development on previously unbuilt lands at the urban fringe, about improved vehicle fuel efficiency under the lower GHG emission scenarios, and about different rates of population growth in the three scenarios.

Under the A2 scenario, transportation emissions related to new development are approximately 789,229 metric tons CO2e annually. The B1 scenario produces similar emissions of 254,243 MT CO2e, compared to 63,244 MT CO2e in the AB 32 scenario. .Residential energy‐related greenhouse gas emissions also show strong differences among the three scenarios, due to the lower energy usage of multifamily units compared with single‐ family homes, as well as other assumptions about different efficiency improvements and electric portfolio composition between the scenarios. Annual electricity‐related emissions from new development built in the 2010 to 2050 time period range from 132,104 MT CO2e in the A2 scenario to 60,548 MT CO2e in the B1 scenario, and just 11,536 MT CO2e in the AB32+ scenario. Holding population constant across the three scenarios diminishes differences only slightly; holding assumptions constant about efficiency improvements and changes to utility portfolio mix still yields substantial differences solely due to the different mix of dwellings between infill‐heavy scenarios and the greater urban sprawl in the A2 scenario. Greenhouse gas emissions from residential gas consumption are slightly higher than for electricity consumption, in part because electricity will become cleaner over time as utilities develop renewable production sources; GHG emissions from gas will remain the same per unit of energy. . Annual gas‐related GHG emissions from new development built in the 2010–2050 time period range from 196,414 MT CO2e in the A2 scenario to 84,384 MT CO2e in the B1 scenario to 15,259 MT CO2e in the AB32+ scenario . Many of these reductions result from different assumptions about improved energy efficiency; if those assumptions are held constant at the A2 level, emissions still decline from 196,414 to 147,673 and 106,813 MT CO2e because of different mixes of dwelling types. Thus, GHG emissions from residential energy use, as from transportation, will be much greater if urban development sprawls onto agricultural land in the countryside. Overall, our three scenarios vary dramatically in their GHG emissions from new urbanization . AB32+ produces much lower GHG emissions from residential development— approximately 8 percent of the emissions in A2, or about 14 percent with population held constant. The B1 scenario also produces substantial GHG savings—about 36 percent and 50 percent of those in A2 under the two different population levels. The strong implication is that preserving agricultural land from development is essential if the county is to stabilize and reduce its GHG emissions. 

The preceding analysis shows that a strong growth management framework for Yolo County, by channeling much or all future development into existing urban areas rather than onto agricultural lands, would have significant value in terms of preserving agricultural land,nft growing system and extraordinary value in terms of reducing the county’s GHG emissions. Agriculture plays a modest role in Yolo County’s GHG emissions; farming occupies approximately 87 percent of the land area, but is estimated to produce only 14 percent of total county‐wide GHG emissions in 1990 . Detailed analysis of all urban GHG emissions in the county are not yet available, yet preliminary estimates suggest that the MT of CO2e per hectare of agricultural lands are >70 times less than cities and towns .The A2 scenario produces a relatively dispersed pattern of growth that consumes more farmland, although it is still a small percentage of the county’s agricultural acreage. This would be likely to occur in a pattern often referred to as “leapfrog development,” in which developers build on separated parcels across the agricultural landscape. Such development would occur primarily between and around the towns of Davis and Woodland. Also, to the extent that urbanization generally makes agriculture more difficult , the A2 scenario could amplify operational or economic hardships due to climate change. Higher‐quality soils are present in the floodplain region near the towns of Davis and Woodland, and support the crops with the highest income per acre . This helps explains why leapfrog development in the A2 scenario resulted in the greatest loss of land classified as either excellent or good soils with the Storie Index. Previous UPlan modeling showed, however, that protecting only prime agricultural land in California’s San Joaquin Valley resulted in greater use of less desirable land, and more urban sprawl than prioritizing compact growth . Beardsley et al. also used UPlan to show that compact growth was the most effective way to preserve biologically valuable land in the Central Valley. Such effects would be somewhat less pronounced in the B1 scenario, although our model shows leapfrog development was still widespread in the same locations, just at lower intensities. The AB32+ scenario prohibits most urbanization of current agricultural land, and so these effects would be essentially nonexistent. In a previous survey, growers with land in the Williamson Act tax relief program were more likely to be concerned about climate change . Individuals who are most committed to agricultural preservation are more likely to recognize the need for options to adapt to climate change, especially to decreased water availability .By fragmenting the landscape in the vernal pools and floodplain, urbanization in the A2 scenario could work against the provision of ecosystem services related to water quality, biodiversity conservation, open space, and its aesthetic and recreational value. By adopting a more “business as usual” story line than B1, the A2 scenario would also be less conducive to investment in new programs to restore wetlands waterways, riparian vegetation, and hedgerows in agricultural landscapes, a strategy that could increase these types of ecosystem services as well as carbon sequestration .Urbanized areas with a large percentage of their land covered by asphalt and other hard surfaces absorb solar radiation and reach ambient temperatures well above the surrounding areas . Road, roof, and parking surfaces within urban areas have been shown to lead to increased speed and volume of storm water runoff and lower groundwater recharge . In a nationwide assessment, the large increase in population and assumption of dispersed development under the A2 scenario results in about 10 percent increase in the surface area of impervious surfaces compared to the B1 story line, and at least one‐third of the nation’s wetlands will be affected by 2050 in both scenarios . Urban planning to date has done relatively little to try to mitigate these effects, and by extension our A2 scenario might continue to produce them, especially since the urban footprint would expand under a “business as usual” story line. However, the story lines of the B1 and AB32+ scenarios might well reduce these effects through extensive tree‐planting in urban areas, reduced amounts of paved surfaces, green roofs, lighter‐colored paving and roofing materials, and other steps. The extent to which urban heat island effects would actually undermine agricultural adaptation in Yolo County, however, is highly uncertain. Towns such as Davis and Woodland are relatively small, and would likely produce much smaller warming effects on surrounding farmland than a larger city like Sacramento. Prevailing winds, particularly on summer evenings, are from the west, and would tend to carry the Sacramento region’s heat toward the Sierra Nevada foothills rather than Yolo County.

The main exception to this general trend is the near term of A2, which showed an unexpected lower frequency of no allocation years . Under the climate only scenarios, where land use is held constant at 2008 crop proportions, future irrigation demand is projected to increase in the District . In the near and medium term, average demand is expected to increase by 80 to 90 thousand acre feet, with no notable differences between the B1 and A2 projections . The increase in demand is expected to continue in the latter part of the century, were the warmer and drier A2 climate sequence ultimately prompts higher irrigation demand than B1 . Relative to the historical period, this is an increase in irrigation demand of approximately 26 to 32 percent due to climate alone. Increased demand and greater impact of the GFDL A2 scenario observed in this study are consistent with previous projections for the Sacramento Valley as a whole . Table 3.5 and Figure 3.5 compare the difference in irrigation demand among the three adaptation scenarios relative to the historic period and climate only scenarios. Under Adaptation 1, demand varies to a small extent above and below the zero lines . This suggests two things. First, it indicates that A2 and B1 cropping patterns predicted by the econometric model, which are based on historic weather and market drivers, have less impact on irrigation demand than climate change alone. For example, increases in demand from climate alone are on the order of tens of thousands of acre feet, while the relative impact of Adaptation 1 is only a few thousand of acre‐feet . Second, since demand in the B1scenario shows a slight increase with Adaptation 1,grow bag for blueberry plants the cropping trend projected by econometric model may be less water efficient than the current cropping pattern.

In short, the econometric model predicts a cropping pattern that is likely to be the most economical or profitable in the short‐term rather than what might be the most water efficient. Differences between the A2 and B1 climate sequences highlight this possibility. Since the econometric model predicted similar cropping patterns for B1 and A2 prior to 2036, irrigation demand was also similar. However beginning in 2036, the acreage of alfalfa expands significantly under the B1 climate . Since alfalfa has high water requirements, its expanded acreage leads to a corresponding increase in total irrigation demand for B1 relative to A2 and the historic period . Adaptation 2 also shows increased demand compared to the historical baseline across all periods and emissions scenarios . However, the model indicates that the increase in demand can be minimized to some extent by shifting to a more diverse and water efficient cropping pattern. That said, the marginal savings towards the end of the century are still less than half of the increase in demand due to climate change alone . Adaptation 3 also shows a near‐term demand slightly greater than the historical period. However, as the diversified cropping pattern and improvements in irrigation technology are gradually implemented, far‐term demand declines to approximately 12 percent less than the historical mean for both the B1 and A2 climate sequences . This illustrates that “game‐changing” water savings—savings of the same order of magnitude of climate‐ induced increases—can occur through a combination of progressive irrigation technology improvement, and cropping patterns which are more water efficient and diversified.Because of an overall increase in irrigation demand, groundwater pumping also tends to increase in the far term under both the B1 and A2 climate . Under A2, the groundwater proportion of the District’s supply rises from a historical mean of around 49 percent in the near term to as high as 61 percent in the far term .

It should be mentioned that this historic estimate includes years prior to the operation of Indian Valley reservoir, thus the present fraction is somewhat lower than 49 percent. Overall, this corresponds to a volume of 118 thousand acre feet above the historical mean . Relative to the climate only scenarios, the marginal benefits of Adaptation 1 and Adaptation 2 are somewhat limited in the near and mid term . In short, by integrating cropping pattern changes and improvements in irrigation technology, groundwater pumping was maintained at levels close to the baseline in the near term and yielded reductions of 30 to 50 TAF in the far term. The survey of growers indicates that these are types of practices that growers foresee as potential adaptation measures in the future . Groundwater pumping, and building more pumps and wells, are adaptation practices that farmers seem likely to adopt in the future, and these are discussed further in Section 5.With the passage of the Global Warming Solutions Act of 2006 ,12 California has shown, in the absence of cohesive federal leadership, that local governments are able to adopt a bottom‐up approach to greenhouse gas mitigation . Specific targets set by AB 32 aim to reduce California’s GHG emissions to 1990 levels by 2020 and a further 80 percent by 2050. Recognizing the key role that land‐ use planning will play in achieving these goals, legislators also passed Senate Bill 375 13 in 2008, which requires regional administrative bodies to develop sustainable land‐use plans that are aligned with AB 32 . Agriculture currently occupies 25.4 percent of California’s total land area and generates approximately 6 percent of the state’s total GHG emissions . By contrast, urban areas in California makeup only 4.9 percent of the land area but are the primary source of the state’s transportation and electricity emissions, estimated at 39 percent and 25 percent, respectively .

Moreover, rapid urbanization in California has contributed to the loss of nearly 3.4 million acres of farmland over the last decade and has increased the emissions associated with urban sprawl . At present, AB 32 does not require agricultural producers to report their emissions or to implement mandatory mitigation measures as it does for California’s industrial sector . The state is, however, encouraging farmers to institute voluntary mitigation strategies through various public and private incentive programs . For example, voluntary mitigation projects within California’s agriculture and forestry sectors may be permitted to sell offset credits in a carbon market that has been proposed in the scoping plan laid out by the California Air Resources Board . While CARB and other state agencies have taken the lead in defining these policies, much of the responsibility for climate change planning and policy implementation has been delegated to local governments. For instance, AB 32 and SB 375 now require local governments to either address greenhouse gas mitigation in the environmental impact report that accompanies any update to their general plan or to carry out a specific “climate action plan” filed separately . Consequently, conducting an inventory of GHG emissions is now among the first steps taken by local governments as they plan for future development. To help local governments improve the quality and consistency of their emissions inventories, CARB has collaborated with several organizations to develop tools to standardize inventory methods. For example, the International Council on Local Environmental Initiatives has developed a software package known as the Clean Air Climate Protection Model to better align local methods with national and international standards . Such inventory tools are suitable for appraising emissions from government or municipal operations,blueberry grow bag but are less useful for “community‐wide” assessments. In particular, the emissions from agriculture are often missing from existing inventory tools geared to local planners due to problems of complexity, data availability, boundary effects, and consistency with methods designed for larger spatial scales . Methods to estimate emissions from agriculture within a local inventory framework would be a valuable asset for those developing mitigation and adaptation strategies in rural communities. In this paper, a local inventory of agricultural GHG emissions in 1990 and 2008 is presented for Yolo County, California. Recent mitigation and adaptation initiatives in Yolo County thus provide the policy context for this analysis .

The main objectives of this inventory of agricultural emissions are to: prioritize voluntary mitigation strategies; examine the benefits and trade‐offs of local policies and on‐ farm practices to reduce agricultural emissions; and discuss how involving agricultural stakeholders in the planning process can strengthen mitigation efforts and lay the groundwork for future adaptation.In this study, an inventory of Yolo County’s agricultural GHG emissions was conducted for both the AB 32 base year and the present period . To address the wide range in data availability and analytical capacity that exists across different national or regional scales, the Intergovernmental Panel on Climate Change advocates a three‐tiered approach for identifying the appropriate inventory methods used for the agriculture sector . This tiered system refers to the complexity and geographic specificity of the inventory method in question; with the Tier 1 methods using a simplified default approach and relatively coarse activity data, while the Tier 3 methods involve more sophisticated models and higher resolution activity data . The Tier 1 methods used here have been adapted for local activity data from three main sources: the CARB Technical Support Document for the 1990–2004 California GHG Emissions Inventory ; 2) the U.S. EPA Emissions Inventory Improvement Program Guidelines ; and 3) the 2006 IPCC Guidelines for National GHG Inventories . Supplementary materials , provide detailed equations, activity data, and emissions factors for each emissions category . While strategies to adapt inventory methods to local data were exchanged with the Yolo County Planning Division during the preparation of their recent climate action plan, the present study is an independent assessment of agricultural GHG emissions.Direct N2O emissions were calculated using a Tier 1 approach that estimated nitrogen inputs from the following sources: synthetic N fertilizers, crop residues, urine deposited in pasture, and animal manure . In Yolo County, 16 crop categories accounted for approximately 90 percent of irrigated cropland. The harvested area of each crop was taken from the county crop reports for 1990 and 2008 . To calculate the total amount of synthetic N applied in Yolo County, the recommended N rate for each crop was multiplied by its cropping area and then summed across all crop categories. For a given inventory year, the recommended N rate for each crop was obtained from archived cost and return studies published by the University of California Cooperative Extension . Nitrogen inputs from crop residues for alfalfa, corn, rice, wheat, and miscellaneous grains were calculated using crop production data taken from the county crop reports . Nitrogen excreted by livestock in the form of urine or manure was calculated for the six main livestock groups assuming year‐round production. Emissions from poultry were not calculated, since no large‐scale poultry operations exist in the county . Dairy cattle numbers for both inventory years were taken from the National Agricultural Statistics Service database , while all other livestock numbers were obtained from the county records . Dairy cattle and swine manure were assumed to be stored temporarily in anaerobic lagoons and then spread on fields. All other livestock categories were assumed to deposit their urine in pastures. Indirect N2O emissions were estimated based on the total amounts of N added as synthetic N fertilizer, urine, and manure; and calculated using standard values for the volatilization and leaching rates, and default emission factors .A Tier 1 approach was developed to calculate fuel consumption from mobile farm equipment. Each crop’s annual harvested area was multiplied by its average diesel fuel use per hectare from archived cost and return studies and then summed across all crop categories to determine the total amount of diesel fuel used each year . The amount of CO2, N2O, and methane emitted was determined by multiplying the total amount of diesel fuel consumed by mobile farm equipment by emission factors for each gas . The Tier 1 estimate of emissions from mobile farm equipment was then compared with results generated by the Yolo County Planning Division who used Tier 3 OFFROAD emissions model . The OFFROAD model estimates end‐use fuel consumption based on detailed information collected on equipment population, activity patterns, and emissions factors . A detailed summary of the OFFROAD model framework and activity data specifications is available from CARB .