Complexity of human and ecosystem interactions in an agricultural landscape

摘要: The complexity of human interaction in the commercial agricultural landscape and resulting impacts on ecosystem services water quality quantity are largely ignored by current paradigm that maximizes crop production over other services. Three examples at different spatial scales (local, regional, global) presented where interactions a adversely affect unintended ways Delta northwestern Mississippi. In first example, little to no regulation groundwater use for irrigation has caused declines levels loss baseflow streams threatening future supply. second federal policy subsidizes corn biofuel encouraged many producers switch from cotton corn, which requires more nutrients water, counter national efforts reduce nutrient loads Gulf Mexico exacerbating groundwater-level declines. third example is wholesale adoption system weed control relies single chemical, initially providing benefits but ultimately leading widespread occurrence glyphosate its degradates necessitating higher application rates as well herbicides due increasing resistance. Although these specific Mississippi Delta, analogous situations exist throughout world point need change how we grow our food, fuel, fiber, manage soil resources.