5Busscher W J,Bjomeberg D L,Sojka R E. Field application of PAM as an amendment in deep - tilled US southeastern coastal plain soils [J]. Soil Tillage Res,2009,104(2) :215 -220.
6Sojka R E, Entry J A, Fuhrmann J J. The influence of high applica- tion rates of polyacrylamide on microbial metabolic potential in an agricultural soil [ J ]. Applied Soil Ecology,2006,32 (2) :243 - 252.