典型黑土区侵蚀-沉积对土壤微生物数量空间分布的影响

研究土壤微生物群落对土壤侵蚀-沉积的响应可为农业生态系统功能提升提供重要指导.选择黑龙江省典型薄层黑土区宾县宾州河流域为研究区,分析土壤微生物数量的空间分布特征,并结合137Cs示踪方法估算土壤侵蚀模数,进一步分析坡面和流域尺度土壤侵蚀-沉积对土壤微生物数量的影响.结果表明:季节变化对土壤微生物数量的影响非常明显,夏季...

Effects of soil erosion and deposition on the spatial distribution of soil microbial quantity in Mollisol area of Northeast China.

Revealing the responses of soil microbial community to soil erosion can provide guidance for agricultural ecosystem management. We investigated the impacts of soil erosion intensity on soil microbial quantity at the Binzhou River Basin, a typical thin layer Mollisol area in Bin County of Heilongjiang Province, using ¹³⁷Cs tracer. The results showed that there were seasonal variations in soil microbial quantity. The abundance of soil microbes in summer was considerably higher than that in autumn. Bacteria was more sensitive to seasonal variation than fungi and actinomycetes, which was increased by 1.4-2.6 times and 1.4-2.2 times in summer compared with autumn in different parts of slope and watershed, respectively. The spatial variation of soil erosion intensity had an important effect on the spatial distribution of soil microbial community. The highest proportion of bacteria was found at lower deposition area of slope (84.4%) and at the lightly eroded area of the downstream (85.4%). The numbers of soil microbes, soil bacteria and actinomycetes were negative linearly correlated with soil erosion modulus, with correlation coefficients of -0.595, -0.554 and -0.291, respectively. Soil erosion and deposition induced spatial differences in soil physical and chemical properties, with consequences on spatial distribution of soil microbial community.