Abstract:Based on the determination of soil microbes and soil enzyme activities,principle component factor analysis was used to build a soil biological properties' effect evaluation system under different models of Grain-for-Green.The results showed that the correlations of the amount of actinomycetes and fungi were significant or very significant with the activities of invertase,urease,cellulose and catalase.The correlations between the dominant microbes and the enzyme activities,including Micrococcus and invertase,Bacillus and ce11u1ase,Trichoderma and catalase,Actinoplanes and catalase,Saccharomyces and urease were positively significant.It indicated that the diversity indices of actinomycetes' and fungal dominant groups were very important to evaluate the soil fertility,as well as the four soil enzymes activities.But bacteria and yeast which had little biomass were less important.The integrated fertility index(IFI)was used to evaluate the plots quality of soil biological fertility.The study indicated that the soil fertility could be ranked as follows:the surface of Pleiohlastus amarus forest>the surface of Betula Luminifera forest>the surface of cropland>the subsurface of cropland>the deep cropland>the subsurface of B.Luminifera forest and P.amarus forest the deep B.Luminifera forest>the deep P.amarus forest. It stated that the ecological improvement of P.amarus forest was better than that of B.Luminifera forest.