1. State Key Lab. of Soil Erosion and Dryland Farming on Loess Plateau; Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources; 26 Xinong Rd. Yangling Shaanxi 712100 Peoples Republic of China
2. U. S. Dep. of Agriculture-Agricultural Research Service (USDA-ARS); Northern Great Plains Research Lab.; P.O. Box 459 Mandan ND 58554
3. USDA-ARS; National Soil Erosion Research Lab.; 1196 SOIL Bldg., Purdue Univ. West Lafayette IN 47907-1196
4. INRA Orléans-Science du Sol; Avenue de la Pomme de Pin, BP 20619 F-45166 Olivet Cedex France
5. USDA-ARS-SPNRU; 2150 Centre Ave., Bldg. D, Suite 100 Ft. Collins CO 80526