4LU C H, VAN ITYERSUM M K, RABBINGE R. Quan- titative assessment of resource-use efficient cropping sys- tems: a case study for Ansai in the Loess Plateau of Chi- na[J]. European Journal of Agronomy, 2003, 19: 311-326.
5ANDREWS S S, KARLEN D I, CAMBARDELLA C A. The soilmanagement assessment framework: a quantita- tive soilquality evaluation method[J]. Soil Science Soci- ety of America Journal, 2004, 68 : 1945-1962.