|Zeng, Fen Li - S&W INST CHINA|
|HUANG, CHI HUA|
|Darboux, Frederic - INRA, FRANCE|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: March 4, 2004
Publication Date: July 31, 2004
Citation: Merrill, S.D., Zeng, F., Huang, C., Tanaka, D.L., Darboux, F., Liebig, M.A., Halvorson, A.D. 2004. Soil erodibility by rainfall on crp lands converted to crop and hay production. Meeting Abstract. Technical Abstract: If grasslands currently under the CRP program are returned to crop production, there are concerns that these lands will experience increased soil erosion. Our objective was to compare runoff, erosion, and soil erodibility on CRP land converted to crop and hay production using rainfall simulation technology. The study was conducted in North Dakota six years after the CRP land had been converted to crop and hay production with a spring wheat ' winter wheat ' dry pea rotation. Agronomic treatments examined were conventional-till (pre-plant disk tillage, CT), no-till (NT), and permanent (annual) haying (PH) on Argiustoll soil. Runoff volumes and soil loss were measured on 1.5- x 5-m bordered runoff plots on 4% slope. Soil erodibility was calculated as the ratio of soil loss rate to runoff rate measured at relative steady state. Erodibility on undisturbed CT, NT, and PH treatments was 1.65, 0.29, and 0.28 g m-2 mm-1, respectively, indicating that NT did not differ from PH and that the single preplant tillage of CT increased erodibility 6-fold above that of PH. Soil erodibility was increased by thorough disk tillage 3-fold for CT, 15-fold for NT, and 9-fold for PH. Of interest to soil conservationists, our results show that chemically weeded (glyphosate and others) NT exhibited the same low erodibility as the grassland PH treatment. However, erodibility of tilled NT was significantly higher than that of tilled PH, reflecting the higher inherent stability of grassland surface soil with its perennial plant root structures.