Fragmentation and loss of farmland causes farmers to lose benefits associated with being part of a large farming community, such as sourcing inputs, accessing information, sharing equipment,and supporting processing and shipping operations . This is further exacerbated by loss of agricultural land near the Sacramento River, either due to future flooding or to mitigation of habitat for wild species. Also, by fragmenting the landscape and consuming more land area in the 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 . Strengthening the urban community’s interest and support of farmland preservation is a key challenge for mitigation of GHG emissions, and the long‐term viability of agriculture in Yolo County. Historically, urban and suburban development has covered many regions within California that were formerly leading agricultural producers, including the Los Angeles Basin and Orange County, much of the San Francisco Bay Area, and areas of the Central Valley near Fresno, Modesto, Merced, Sacramento, and Stockton. Between now and the year 2050 much additional urbanization is likely near these metropolitan areas, as well as in locations that are at a considerable distance from existing major cities, such as the Salinas Valley and Ventura County. Strategies to preserve agricultural land from urbanization are likely to dovetail with strategies to adapt to climate change and mitigate greenhouse gas emissions, reducing the state’s overall vulnerability to climate change. For example, maintaining a strong greenbelt of agricultural land around existing urban areas and adopting compact urban development policies can greatly reduce GHG emissions , while preserving agricultural production and potentially enhancing ecosystem services. This section considers urbanization implications related to agriculture and climate change,strawberry gutter system based on statewide modeling of 2050 urban growth scenarios, using existing datasets regarding agricultural production, land use, and soils.
The actual complexities of urban‐agriculture interactions require a great deal of monitoring and interdisciplinary synthesis that is beyond our scope, e.g., urban heat island or ozone effects may lead to additional vulnerabilities for agriculture with climate change. Our aim here is instead to present an initial overview of potential agricultural adaptation and vulnerability effects related to urbanization, and to suggest directions for further research. The strong policy framework in California for GHG mitigation under AB 32, the Global Warming Solutions Act of 2006, has drawn attention to the fact that California’s urban planning framework is in a state of uncertainty and potential transition. SB 375, the Sustainable Communities and Climate Protection Act of 2008, requires Metropolitan Planning Organizations within the state to prepare “sustainable communities strategies” that show how each region will meet GHG‐reduction targets through integrated land use, housing, and transportation planning. As of 2011, MPOs are just beginning to develop such plans. SB 375 is widely seen as having the potential to usher in a new era of land use planning in California, in which regional “blueprints” will be adopted to manage and reduce urban and suburban expansion . However, it is by no means clear how the California Air Resources Board or the legislature will react to ensure that such potential is in fact met. In addition, as of 2010 every county and municipality in the state must now consider GHG emissions within their General Plans and associated Environmental Impact Reports . Since 2007, the state Attorney General’s office has frequently threatened legal action against those jurisdictions that do not include planning alternatives to reduce GHG emissions . The California Air Resources Board is also strongly encouraging local governments and large institutions to prepare Climate Action Plans and GHG emissions inventories, and many have already done so.
These actions mean that local governments are now more actively exploring land use planning alternatives to mitigate GHG emissions and adapt to climate change. Although political resistance to growth management will certainly continue, such trends mean that in the future the state’s local governments are more likely to consider growth management scenarios that respond to the twin goals of preserving agricultural land and responding to climate change. This institutional and political environment affects our analysis below, and will be referred to when appropriate.To analyze the impact of future urbanization scenarios on agricultural landscapes within California within the context of climate change, we relied on modeling done by the UC Davis Information Center for the Environment using UPlan software under a separate portion of this Climate Change Vulnerability and Adaptation Study for California. We then performed additional analyses on the UPlan projections for 2050, using statewide data on agriculture, land use, and soils. UPlan is a geographic information system ‐based land use allocation model developed by ICE and used for urban planning purposes by more than 20 counties in California, including a number of rural counties in the San Joaquin Valley . It is particularly useful for large‐scale urban growth scenarios in rural areas, and has been used in a research context to analyze urbanization effects on natural resources , urbanization effects on wildfire risk , and the effect of land use policies on natural land conversion . Using UPlan, researchers first develop a base of GIS information related to geographical features such as roads, rivers and streams, floodplains, parkland, and existing urban areas. They then supply demographic inputs within future urban growth scenarios. Researchers also specify geographical features that are likely to attract urban growth , discourage growth , or prevent growth , and assign weightings to each. For example, freeway interchanges may attract development, since builders desire the locational advantages.
Designation as prime farmland may discourage development, since local governments may take this factor into account within their zoning and growth management policy making, and farmers may participate in the Williamson Act or other programs designed to discourage urbanization. Acquisition of land as public open space will prevent urbanization altogether, thus making a “mask” designation appropriate within UPlan. Relying on the combined weightings for each 50‐meter grid cell, UPlan allocates the future population increase across four residential land use types , and several nonresidential land use types . The result is a spatial projection of future urbanization with designations for each land use type. ICE staff developed two main UPlan scenarios for statewide mapping within this project scenario of urban development. The other is a “smart growth” alternative that clusters development into nodes, specifies somewhat higher densities, and places more development within existing city borders. Such scenarios reflect growth management philosophies within the state during recent decades; many local and regional planning agencies have developed similar alternatives within their own planning processes. The ICE SG scenario is relatively conservative and does not assume any dramatic changes to current planning policies. In reality, over the past two decades,grow strawberry in containers development within the state near large metropolitan areas has become increasingly compact and focused on infill sites rather than greenfield locations. The California agricultural areas most affected by urbanization between now and 2050 will not necessarily be those with the greatest overall amount of new urban and suburban development. Rather, other factors will come into play. These include the amount of agricultural base remaining within the region, the extent to which urban development fragments agricultural landscapes, and the extent to which farmers benefit from increased access to urban markets. If there is relatively little agricultural base left, as is currently the case around some of the state’s large metropolitan areas, then it becomes more difficult for farmers to find suppliers, processors, and other agricultural support functions . This may affect farm operations on a crop‐by‐crop basis. For example, there is only one processor of apples left in Sonoma County, formerly home to extensive apple orchards, and if that facility closes, then production of classic varieties such as Gravensteins will become difficult . If urban development fragments agricultural land into isolated pockets separated by roads, subdivisions, office parks, and other urban facilities, then it becomes more difficult for farmers to move equipment from field to field, and conflicts may arise with new suburban residents over noise, odor, and potential spraydrift associated with farming operations. Fragmentation may also reduce the benefits farmers receive from being part of a large farming community, such as sourcing inputs, accessing information, sharing equipment, and supporting processing and shipping operations . Impacts on agriculture from urbanization will then be disproportionate to the land area covered. On the other hand, urbanization can benefit agriculture if it increases access to markets . This factor is likely to benefit some types of agriculture more than others. Specialty production of fruits, vegetables, meats, and dairy products for use by restaurants, distribution through high‐end grocery stores, and sale at farmers’ markets and through community‐ supported agriculture networks is likely to benefit. Conversely, production of grains and lower‐ value fruits and vegetables is not likely to see a boost from the presence of local markets, since farmers primarily sell these bulk commodities to large‐scale processing facilities for regional, national, or international distribution .Addressing climate change is a priority issue for Californians and involves individuals, businesses, and government.
The Global Warming Solutions Act of 2006 seeks to reduce the emission of greenhouse gases to 1990 levels by 2020. This legislation goes into effect gradually, so that people will have time to implement the necessary actions to come into compliance by the 2020 deadline. Some businesses, however, are proactive on climate change mitigation, and are signing up through mechanisms such as the Climate Action Registry to become leaders and early adopters of GHG emission‐reduction programs. By making progress toward carbon neutrality ahead of deadlines, these companies may qualify for incentive programs and be recognized as environmental leaders. Among such leaders are a number of wine companies that are managing their vineyard lands and adjoining forests that maximize biomass on the landscape and balance the emissions generated in their production processes. This paper is a case study about one such company, Fetzer/Bonterra Vineyards, who has set their objectives to reduce their GHG emissions and use renewable sources to meet much of its energy demands. As an environmentally conscious business, and a major grower and producer of wines, Fetzer/Bonterra attempts to achieve a balance between habitat conservation, ecologically based organic production, production goals, and financial profit. When the company purchased ranches for growing grapes in Mendocino County, a decision was made to maintain a large fraction of that land in natural habitat without livestock grazing. This was based on an environmental ethic to combine wine production with conservation of the landscape’s natural integrity. This approach also included a series of sustainability measures . To learn more about the carbon storage and dynamics on its land, Fetzer/Bonterra collaborated with researchers at the University of California Davis to conduct an assessment of the distribution and magnitude of carbon stored across the vineyard‐woodland landscape. The main goal was to find a way to assess carbon stocks to determine the absolute and relative amounts of carbon stored in different vegetation and land use types. Fetzer/Bonterra’s rationale behind the assessment was to identify the relative value of the different vegetation types on their land in terms of contributing to the positive, or offset, side of their carbon budget. Because the study also collected data on the different woody plant species, information on the diversity of plant communities was obtained. The species and community diversity data make it possible to assess the relationship between carbon stocks and biodiversity, and to show how habitat type affects the magnitude of C stocks. This approach will allow vineyard managers to prioritize non‐vineyard land for carbon storage, biodiversity and habitat conservation, and eventually other types of ecosystem services, such as keeping steep slopes and stream corridors forested to protect against erosion and sediment loading in waterways. Greater carbon stocks in forests is to be expected, but it is significant to recognize that Fetzer/Bonterra uses a management approach for a combination of perennial woody crops and conserved habitat that maximizes the contribution of the heterogeneous landscape to total carbon stocks. Using this Fetzer/Bonterra case study experience as an example, this paper showcases the important role that California agricultural landscapes can play in climate change adaptation and mitigation strategies.