HR: 0800h
AN: B41B-0453    [Abstracts]
TI: Mind the Gap: How do climate and agricultural management explain the "yield gap" of croplands around the world?
AU: * Licker, R
EM: rlicker@wisc.edu
AF: Center for Sustainability and the Global Environment, Nelson Institute for Environmental Studies, University of Wisconsin-Madison, 1710 University Ave., Madison, WI 53726, United States
AU: Foley, J A
EM: jfoley@wisc.edu
AF: Center for Sustainability and the Global Environment, Nelson Institute for Environmental Studies, University of Wisconsin-Madison, 1710 University Ave., Madison, WI 53726, United States
AU: Johnston, M
EM: mjohnston@wisc.edu
AF: Center for Sustainability and the Global Environment, Nelson Institute for Environmental Studies, University of Wisconsin-Madison, 1710 University Ave., Madison, WI 53726, United States
AB: At present, cultivated lands extend across approximately fifteen million square kilometers of the Earth's surface, making it one of the most dominant land cover types. The management practices used on these lands have become increasingly intensified, requiring large inputs of fertilizers and water, in addition to mechanization and biotechnology. These intensified practices have had implications for ecosystem goods and services ranging from water quality and availability to carbon sequestration. However, the billions of additional people that are projected to inhabit the planet in the twenty-first century will require further outputs from our global agricultural system. Given our food system's already expansive and intensive state, it is important to consider where the additional yields might come from and what additional management inputs this might require. In this study, we compare yields both within crop types and within regions of similar climate to determine where yield gaps exist. We do so using recently created, five-minute datasets of the area harvested and yield of 175 different crop types for the year 2000. We also explore the links of these yield gaps to global patterns of management. For example, we consider the ways in which management practices such as irrigation and fire are influencing yields around the world - analyses that can help critically evaluate the level of management currently employed and help imagine what management might be necessary to achieve higher yields in the future. These data will be needed in the next generation of Earth System models, in order to better represent the practices of agricultural land use in more realistic ways, thereby improving our understanding of land use / land cover change on the global carbon and water cycles, and the climate system.
DE: 0402 Agricultural systems
DE: 0439 Ecosystems, structure and dynamics (4815)
DE: 1632 Land cover change
SC: Biogeosciences [B]
MN: 2007 Fall Meeting