Sowing the Seeds of Soil Conservation

Abstract

In their Perspective (“Monitoring earth's critical zone,” 20 November 2009, p. [1067][1]), D. deB. Richter Jr. and M. L. Mobley argue for the importance of monitoring Earth's belowground critical zone for sustaining life and humanity. Their message echoes a similar call from a different era. “The Nation that destroys its soil destroys itself.” These words of President Franklin Delano Roosevelt in his 1937 letter to all state governors referred to the Soil Conservation Act of 1935, which recognized the need to sustain soil resources. The Standard Soil Conservation District law was subsequently adopted by all 50 states, plus Puerto Rico and the Virgin Islands. Historical aerial photos across the country from 1947 to 2004 ([ 1 ][2]) provide evidence that the law has been effective in protecting many farmlands and show that visible erosion in the form of gullies is now almost nonexistent in comparison with the erosion that occurred in the 1930s. In the decades since the Natural Resources Conservation Service started the National Resources Inventory in 1982, soil erosion on U.S. croplands has decreased 43% ([ 2 ][3]). ![Figure][4] Fighting erosion. Contour stripcropping is one method used to protect soils. CREDIT: RON NICHOLS/USDA-NRCS Laws like the one President Roosevelt championed in the 1930s are more important today than ever. Urban sprawl, land degradation, environmental pollution, and anthropogenically accelerated erosion (to name just a few) are detrimental to sustainable food production and quality water supply for the growing world population. Modern soil vulnerability to global change and anthropogenic threats (beyond just croplands) is unprecedented. This issue was not addressed in the 1930s law but could have devastating effects. Monitoring and protecting the belowground critical zone is a crucial step to ensure that we do not lose ground for sustainability. 1. [↵][5] 1. L. E. Mathews , Aerial Photography Field Office Historical Imagery Holdings for the United States Department of Agriculture (2005); [www.apfo.usda.gov/Internet/FSA\_File/vault\_holdings2.pdf][6]. 2. [↵][7] Natural Resources Conservation Service, National Resources Inventory 2003 Annual NRI: Soil Erosion (2007); [www.nrcs.usda.gov/technical/NRI/2003/SoilErosion-mrb.pdf][8]. [1]: /lookup/doi/10.1126/science.1179117 [2]: #ref-1 [3]: #ref-2 [4]: pending:yes [5]: #xref-ref-1-1 View reference 1 in text [6]: http://www.apfo.usda.gov/Internet/FSA_File/vault_holdings2.pdf [7]: #xref-ref-2-1 View reference 2 in text [8]: http://www.nrcs.usda.gov/technical/NRI/2003/SoilErosion-mrb.pdf