---

作 者 ：任万军¹;刘代银^1,2;吴锦秀¹;伍菊仙¹;陈德春¹;杨文钰¹

期 刊 ：应用生态学报 2009年 20卷 04期 页码：817-822

关键词：稻；

摘 要 ：通过大田试验，研究了不同秸秆还田和耕作方式（免耕+秸秆还田、免耕、常耕+秸秆还田、常耕）对稻田不同层次土壤肥力和主要微生物类群数量的影响.结果表明：上层土壤中，免耕+秸秆还田处理的有机质含量分别比免耕、常耕+秸秆还田和常耕处理高5.33、2.79和5.37 g·kg^-1;全氮、全磷、全钾、碱解氮、速效磷和速效钾含量也均以免耕+秸秆还田处理最高，免耕和常耕+秸秆还田处理次之，常耕处理最低.下层土壤中，各肥力指标以常耕+秸秆还田处理较高.秸秆还田各处理微生物类群数量较高，上层土壤以免耕+秸秆还田处理的细菌、真菌和放线菌数量最高，成熟期其纤维分解强度分别比常耕+秸秆还田、免耕和常耕处理高26.44%、79.01%和98.15%;下层土壤以常耕+秸秆还田处理的细菌、真菌和放线菌数量最高.免耕+秸秆还田处理的土壤养分和微生物呈表层富集特征.细菌、放线菌和纤维分解强度与土壤肥力各指标呈显著或极显著正相关关系.

Abstract:A field experiment was conducted on a paddy field to study the effects of returning straw to soil and different tillage methods (no-tillage + returning straw, no-tillage, tillage + returning straw, and tillage) on the fertility level and microbial quantities of different soil layers. The results showed that in upper soil layer, the organic matter content in treatment ‘no-tillage + returning straw’ was 533, 279, and 537 g·kg-1 higher than that in treatments ‘no-tillage’, ‘tillage+returning straw’, and ‘tillage’, respectively, and the contents of total and available N, P and K in treatment ‘no-tillage+returning straw’ were also the highest, followed by in treatments ‘no-tillage’ and ‘tillage+returning straw’, and in treatment ‘tillage’. In deeper soil layer, all the fertility indices were higher in treatment ‘tillage+returning straw’. Treatments of ‘returning straw to soil’ had the highest quantities of soil microbes. The quantities of bacteria, fungi, and actinomycetes in upper soil layer were the highest in treatment ‘no-tillage + returning straw’, and thus, the cellulose decomposition intensity in this treatment at maturity period was 2644%, 7901%, and 9815% higher than that in treatments ‘tillage+returning straw’, ‘no-tillage’, and ‘tillage’, respectively. In deeper soil layer, the quantities of bacteria, fungi, and actinomycetes were the highest in treatment ‘tillage+returning straw’. Treatment ‘no-tillage+returning straw’ had the features of high fertility and abundant microbes in surface soil layer. The quantities of soil bacteria and actinomycetes and the decomposition intensity of soil cellulose were significantly positively correlated with soil fertility level.

---