|Mitchell, Charles - UNIV OF NORTH CAROLINA|
Submitted to: Ecological Society of America Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: February 28, 2006
Publication Date: August 6, 2006
Citation: Blumenthal, D.M., Mitchell, C.E. 2006. Food and diversity: balancing the intensive and extensive agriculture. Ecological Society of America Abstracts. p. 24. Technical Abstract: Food is central to human well being. Its production is also the primary threat to biological diversity. Although this conflict is widely recognized, it is not clear how agricultural systems should be organized to minimize it. Of particular importance is the question of how intensively we should farm, fish or raise livestock. One idea is that intensification, by increasing productivity per unit area, reduces the demand to convert natural to agricultural ecosystems. Recent models propose that this logic will apply in systems where diversity decreases exponentially with agricultural intensification. Many crop production systems appear to fit that description, suggesting that agricultural intensification may be an important approach to conservation. However there are notable exceptions to this conclusion. Specific synergies between production and diversity may sometimes make less intensive agriculture the most effective route to conservation. One such exception is the sustainable harvest of native species through fishing, hunting, or grazing of native grasslands. In such systems productivity, though low relative to crop production, can be maintained without greatly reducing diversity. Furthermore, because production relies on diversity in such systems, the economic value of that production can help conserve diversity. The second exception has to do with scale: at landscape scales, diversity may not decrease exponentially with production. Even within landscapes dominated by intensive crop production, small areas of non-cropland can maintain some diversity, and reduce off-site impacts of fertilizer and pesticides. Further, maintenance of diversity within agricultural landscapes can enhance agricultural production by providing supporting ecosystem services including pest control and pollination. Together, these patterns suggest that research efforts should be directed towards increasing productivity at the field scale in cropping systems, and preserving diversity both in harvestable ecosystems and at landscape scales.