HR: 16:00h
AN: B44B-01 INVITED [Abstracts]
TI: Against the Grain: The Influence of Changing Agricultural Management on the Earth System
AU: * Foley, J A
EM: jfoley@wisc.edu
AF: Center for Sustainability and the Global Environment (SAGE), University of Wisconsin
1710 University Ave., Madison, WI 53726,
AB:
The rise of modern agriculture was one of the most transformative events in human history, and has forever
changed our relationship to the natural world. By clearing tropical forests, practicing subsistence agriculture on
marginal lands and intensifying industrialized farmland production, agricultural practices are changing the
worldês landscapes in pervasive ways. In the past decade, we have made tremendous progress in monitoring
agricultural expansion from satellites, and modeling associated environmental impacts. In the past decade, the
Earth System Science research community has begun to recognize the importance of agricultural lands,
particularly as they continue expanding at the expense of important natural ecosystems, potentially altering the
planetês carbon cycle and climate. With the advent of new remote sensing and global modeling methods, several
efforts have documented the expansion of agricultural lands, the corresponding loss of natural ecosystems, and
how this may influence the earth system.
But the geographic expansion of agricultural lands is not the whole story. While significant agricultural expansion
(or extensification) has occurred in the past few decades, the intensification of agricultural practices Ð under
the aegis of the –Green Revolution" Ð has dramatically altered the relationship between humans and
environmental systems across the world. Simply put, many of the worldês existing agricultural lands are being
used much more intensively as opportunities for agricultural expansion are being exhausted elsewhere. In the
last 40 years, global agricultural production has more than doubled Ð although global cropland has
increased by only 12% Ð mainly through the use of high yielding varieties of grain, increased reliance on
irrigation, massive increases in chemical fertilization, and increased mechanization. Indeed, in the past 40 years
there has been a 700% increase in global fertilizer use and a 70% increase in irrigated cropland area. While
these modern agricultural practices have successfully increased food production, they have caused extensive
environmental damage across the planet.
Unfortunately, the current generation of remote sensing datasets and global models only considers the
geographic extent of agricultural land; the actual practice of agriculture (what is grown, how it is grown, what
inputs are used) is almost completely ignored. This is a serious oversight.
In this presentation, I will present new efforts to document the patterns of global agricultural practices and
management regimes, and new techniques for incorporating them into global ecological and climate models.
DE: 0402 Agricultural systems
DE: 1632 Land cover change
SC: Biogeosciences [B]
MN: 2007 Fall Meeting