【摘要】 在不同时期采集了砾石覆盖,未覆盖连作西瓜农田和撂荒地的表层土壤,测定了土壤中主要微生物数量和过氧化氢酶、淀粉酶、多酚氧化酶及脱氢酶酶活性,并研究了作物生育期内土壤酶活性的变化特点。结果表明,砾石覆盖处理的农田土壤微生物数量处于较低水平,其真菌数量发生了显著下降,而细菌和放线菌数量则介于未覆盖农田和撂荒地之间。在整个生育期内,不同处理下土壤酶活性变化显著不同,但多在西瓜生长旺盛的抽蔓期和结果期达到极值。作物生长和砾石覆盖对于酶活性的影响作用很大,这为进一步研究砾石覆盖对农田土壤环境影响的机理及砾石覆盖科学管理提供基础依据。更多还原

【Abstract】 Topsoil samples were collected from unmulched cropland,abandoned cropland and continuous watermelon cropland at different times.The samples were analyzed for soil microbial population and catalase,amylase,polyphenol oxidase and dehydrogenase activities.Then the dynamic characters of soil enzyme activities in crop growth period were studied.The soil microbial population of cropland with gravel-sand mulch was at a low level,the number of fungi decreased significantly,and both of the number of bacteria and actinomycetes in mulched cropland were between those in unmulched cropland and abandoned cropland.Dynamic characters of soil enzyme activities in different treatments were significantly different in crop growth period and however,most of soil enzyme activities reached a maximum value in vining stage or fruiting period.The crop growth and gravel-sand mulch had strong effects on soil enzyme activities.The results can provide a theory basis for the sustainable utilization and scientific management of the gravel-sand mulch cropland.更多还原