冬季温室土壤中不同方式添加水稻秸秆的腐解及其土温效应研究

Study on the effects of different returning ways on rice straw decomposition and soil temperature in greenhouse in winter

[目的]分析冬季温室土壤不同方式添加水稻秸秆的土壤温度变化及秸秆腐解率的变化,为探讨水稻秸秆移位用于冬季温室土壤增温提供参考。[方法]考虑秸秆用量、秸秆粉碎、添加养分和添加腐熟菌剂等4个因素,设计了7个秸秆还田方式处理,以不添加秸秆为对照,采用多点温度测量装置测定土壤温度,通过测定秸秆失重率及残余秸秆灰分含量等表征秸秆腐解率。[结果]水稻秸秆辅以牛粪或腐熟菌剂在冬季温室沟埋腐解,可显著提升冬季温室土壤表层土温,有效缩小土壤温差:在冬季气温最低时,水稻秸秆辅以牛粪处理比对照提升土温0.8℃,辅以腐熟菌剂处理比对照提升土温1.1℃;在90 d的试验期间,所有秸秆处理土壤温差平均降低0.7℃,而水稻秸秆辅以牛粪处理土壤温差降低2.0℃,秸秆量为2%的处理土壤温差平均降低2.9℃,但秸秆量为1%且辅以腐熟菌剂处理土壤温差平均降低3.1℃。秸秆在温室内集沟还田并辅以适宜的辅助剂还可提高水稻秸秆的腐解率:试验期结束后,未添加辅助剂的秸秆处理组的秸秆失重率为55.96%,辅以腐熟菌剂处理组的秸秆失重率提高到58.33%;辅以牛粪的处理中,腐解产物的残余灰分含量比对照提高12.6%,辅以腐熟菌剂的处理比对照提高26.0%。[结论]水稻秸秆配施菌剂集沟添加于冬季温室能促进秸秆腐解,提升土温,降低温差,是为温室植物生长提供稳定温度环境的有效方式。

[ Objectives ] The purpose of the study was to determine the effects of different rice straw returning ways on soil temperature of greenhouse and straw decomposition rate, to provide reference in increasing greenhouse soil temperature in winter and promoting straw decomposition process. [ Methods ] Seven treatments were designed based on four factors as amount of rice straw, chopped or whole straw, addition of cattle manure and decomposing agents. Temperature sensors were used for soil temperature measurements, and decomposition rate was expressed by weight loss rate and residual ash content after 90 days. [ Results ] The decomposition of rice straw, with cattle manure or decomposing agents mixed, had significant effect on raising soil temperature and reducing soll temperature differences. Compared to CK,soil temperature was raised by 0.8℃in the coldest day with rice straw and cattle manure applied into soil, and by 1.1℃ with rice straw and decomposing agents. Soil temperature difference was reduced by 0.7℃ , 2.0 ℃, 2.9 ℃ and 3.1 ℃ in average throughout the experiment, under treatments of only rice straw, rice straw and cattle manure,rice straw and cattle manure and decomposing agents, and rice straw and decomposing agents, respectively. Rice straw decomposition could be enhanced with rice straw and addietives applied into soil. Compared with 55.96% of weight loss rate at the end of the experiment period（ 90 days）with only straw applied ,58.33% of weight loss rate was reached with straw and decomposing agent applied. Compared with the control, the residual ash content was raised by 12.6% and 26.0%, with straw and cattle manure, and with straw and decomposing agent applied, respectively. [ Conclusions ] In conclusion, application of rice straw mixed with decomposing agents into greenhouse soil in winter was an effective way to promote straw decomposition, raise soil temperature and reducing soil temperature difference, thus providing greenhouse plants with stable soil temperature.