Toward Sustainable Agricultural Systems in the 21st Century (2010)

U.S. agriculture has had an impressive history of productivity that has resulted in relatively affordable food, feed, and fiber for domestic purposes and increases in agricultural exports. Fewer farmers are producing more food and fiber on about the same acreage, while input and energy use per unit output has decreased over the last 50 years. Despite these tremendous advances, U.S. farmers are facing the daunting challenges of meeting the food, feed, and fiber needs of the nation and of a growing global population and of contributing to U.S. biofuel production, under the constraints of rising production costs, increasingly scarce natural resources, and climate change. Agriculture is at a pivotal stage in terms of meeting societal demands for products while improving sustainability.

This report of the National Research Council Committee on Twenty-First Century Systems Agriculture reviews the state of knowledge on farming practices, technologies, and management systems that have the potential to improve the environmental, social, and economic sustainability of agriculture, and it discusses the tradeoffs and risks that might occur if more farms were to adopt those practices, technologies, and systems. The report also identifies knowledge gaps and makes recommendations for future actions to improve agricultural sustainability.

Improving sustainability is a process that moves farming systems along a trajectory toward meeting various socially determined sustainability goals as opposed to achieving any particular end state. Agricultural sustainability is defined by four generally agreed-upon goals:

• Satisfy human food, feed, and fiber needs, and contribute to biofuel needs.

• Enhance environmental quality and the resource base.

• Sustain the economic viability of agriculture.

• Enhance the quality of life for farmers, farm workers, and society as a whole.

The sustainability of a farming practice or system could be evaluated on the basis of how well it meets various societal goals or objectives. To be sustainable, a farming system needs to be sufficiently productive, robust (that is, be able to continue to meet the goals in the face of stresses and fluctuating conditions), use resources efficiently, and balance the four goals.

All farms have the potential and responsibility to contribute to different aspects of sustainability. However, the scale, organization, enterprise diversity, and forms of market integration associated with individual farms provide unique opportunities or barriers to improving their ability to contribute to global or local food production, ecosystem integrity, economic viability, and social well-being. Dramatic and continuous improvement in agricultural sustainability will require long-term research, education, outreach, and experimentation by the public and private sectors in partnership with farmers.

The committee proposes two parallel and overlapping efforts to ensure continuous improvement in the sustainability performance of U.S. agriculture: incremental and transformative. The incremental approach would be directed toward improving the sustainability performance of all farms, irrespective of size or farming system type, through development and implementation of specific sustainability-focused practices, many of which are the focus of ongoing research and with varying levels of adoption. Most, if not all, farms have adopted some practices for improving sustainability, but such methods have not been adapted to all environments, and none of the practices has reached its full potential for adoption. Continuous research, extension, and experimentation by researchers and farmers are necessary to provide the toolkit necessary for farmers to adapt their systems to the changing environmental, social, market, and policy conditions to ensure long-term sustainability.

Research has to address multiple dimensions of sustainability and explore agroecosystems properties if systemic changes in farming systems are to be pursued. Therefore, the incremental approach to improving agricultural sustainability needs to be complemented by a transformative approach that would dramatically increase integrative research by bringing together multiple disciplines to address key dimensions of sustainability simultaneously beyond the agroecological dimension. The transformative approach would apply a systems perspective to agricultural research to identify and understand the significance of the linkages between farming components and how their interconnectedness and interactions with the environment make systems robust and resilient over time.

The decisions of farmers to use particular farming practices and their ability to move toward increasingly sustainable farming systems are influenced by many external forces, including science, knowledge, skills, markets, public policies, and their own values, resources, and land tenure arrangements. Although market, policy, and institutional contexts are important drivers of the trajectory of U.S. agriculture, the response of individual farmers to the incentives and disincentives created by market conditions and policy contexts can be diverse. Efforts to promote widespread adoption of different farming practices and systems for improving sustainability will require an understanding of how variability among individual, household, farm, and regional-level characteristics affect farmers’ response to incentives and disincentives.