油菜秸秆、紫云英绿肥及其不同比例配施还田的腐解及养分释放规律研究

Study on characteristics of decomposing and nutrients releasing of different proportional mixture of rape straw and Chinese milk vetch in rice field

试验以油菜秸秆和紫云英（Astragalus sinicus L.）为研究材料,通过盆栽模拟稻田条件,研究了油菜秸秆、紫云英绿肥及其不同比例混合处理腐解及养分释放动态。结果表明,腐解过程均呈现出前10~20 d分解较快,后期分解较慢并逐渐趋于平稳的规律。不同处理各养分的释放快慢不同,表现为钾〉磷〉氮〉碳,在翻压90d时钾的累积释放率为95.09%~97.17%,磷的累积释放率为62.65%~87.14%,氮的累积释放率为70%~76.48%,碳的累积释放率为39.53%~64.69%。翻压90 d后紫云英腐解率达到60.07%,油菜秸秆仅40.8%,混合紫云英后,混合处理的腐解程度加快,且腐解程度随紫云英量的增加而增加。

The decomposition dynamics of the returned straw of rape,Chinese milk vetch and their mixtures with different proportions in submerged paddy soil were studied under pot experiment. The result showed that the decomposition rate of rape straw,Chinese milk vetch and their mixtures in soil was fast in the first 10 - 20 days,slowed down after that,and then kept stable. The nutrient release rate was K P N C. At 90 days after incubation,the K release rate was 95. 09% - 97. 17%,P release rate was 62. 65% - 87. 14%,N release rate was 70% - 76. 48%,and C release rate was 39. 53% - 64. 69%. At the end of the experiment,the decomposition rate of the Chinese milk vetch and rap straw were 60. 07%,40. 8%,respectively. The decomposition rate of mixtures was improved when Chinese milk vetch was mixed in,and the rape straw decomposition rate was boosted with the increasing amount of Chinese milk vetch.