Biofuels And Biodiversity In California: Trade-off Analysis
Biofuels from agricultural and other biomass are an important part of California’s strategy to reduce greenhouse gas emissions and dependence on foreign oil. Ongoing land conversion for agricultural and urban uses has already imperiled many animal species in the state. This study investigated the potential impacts on wildlife of shifts in agricultural activity to increase biomass production. We applied knowledge of the suitability of California’s agricultural landscapes for wildlife species to evaluate wildlife effects associated with plausible scenarios of expanded production of five potential biofuel crops (sweet sorghum, sugar beets, bermudagrass, canola, and safflower). We generated alternative, spatially-explicit scenarios that minimized loss of habitat for a given level of biofuel production. Trade-off analysis compared the marginal changes per unit of energy for transportation costs, wildlife, and water-use. The choice of crop matters. Sweet sorghum and sugar beets require three times less land area per gallon of gasoline equivalent than bermudagrass and five to six times less than canola and safflower. Canola and safflower scenarios had the largest impacts on wildlife but the greatest reduction in water use. The bermudagrass scenarios would result in a slight overall improvement for wildlife over the current situation. Relatively minor redistribution of lands converted to biofuel could produce the same energy yield with much less impact on wildlife and very small increases in transportation costs for any crop. This framework provides a means to systematically evaluate potential wildlife impacts of alternative production scenarios. The accuracy of the predicted impacts could be improved with additional field study of wildlife use of agricultural landscapes, especially habitats associated with biofuel crops.