【摘要】 通过对我国南方稻区不同冬季覆盖作物前茬对稻田主要微生物类群数量和主要土壤化学性状的变化进行研究,结果表明:冬季紫云英和黑麦草覆盖在翌年水稻田翻耕前土壤好气细菌、真菌、放线菌数量均比冬闲田高,其中好气性细菌数量差异最显著,分别是冬闲田的94.29%和25.71%;在水稻整个生长过程土壤细菌、真菌和放线菌均呈现移栽后前期迅速增加,然后随着水稻的生长发育逐渐下降,到早稻成熟期有渐渐回升,晚稻收获时又迅速下降的趋势,并且不同时期微生物数量冬季紫云英和黑麦草区均比冬闲田要高。土壤微生物活度在水稻生长过程呈增加的趋势,前茬冬季覆盖作物区明显高于冬闲田。另外土壤微生物活度与土壤有机碳含量存在显著的相关性(r2=0.887,P<0.05)。冬季种植覆盖作物对稻田土壤微生物有很强的改善作用,促进了土壤养分利用。更多还原

【Abstract】 Winter cover crop effects on soil microbe and biochemical properties.This study examined microbe and its relation to soil fertility in paddy soil in southern China.The main results shows: the use of cover crop such as Chinese milk vetch and ryegrass had higher amount of aerobic bacteria,fungi,actinomycetes than fallow treatments before paddy soil tillage in the second year.The amount of soil aerobic bacteria,fungi,actinomycetes ascended at the early stage and then declined during rice growth,but ascended slightly again at early rice maturity.The difference of amount of aerobic bacteria was significant,respectively enhancing 94.29% and 25.71%.The former-stubble crop treatments were higher amount of microbe than winter fallow stubble during early rice growth.Soil microbial activity ascened at satge of rice growth and declined at later rice maturity.The positive correlation between soil microbial activity and soil organic carbon was significant(r2=0.887,P<0.05)There was a positive correlation between soil aerobic bacteria,fungi,actinomycetes and soil biochemical.更多还原