Effects of conservation tillage with straw cover or straw standing on the soil microbial biomass carbon and organic matter | 留茬覆盖免耕保护性耕作对土壤微生物量碳和有机质含量的影响_

Chinese. ［目的］ 揭示不同土壤耕作方式对土壤肥力的影响。［方法］ 在大田试验中，设20 cm留茬压倒（NPS20）、40 cm留茬压倒(NPS40)、40 cm立秆(NS40)、20 cm立秆(NS20)、6 750 kg/hm_2秸秆覆盖(NSB40)、3 750 kg/hm_2秸秆覆盖(NSB20)和传统耕作(CT)7个处理，研究不同秸秆覆盖量、留茬高度和秸秆处理对土壤有机质、土壤微生物量碳的含量和作物产量的影响。［结果］ 土壤微生物量碳含量春季播种前最高，夏季收获后最低。不同时期的土壤耕作措施对土壤微生物量碳的影响不同。从播种期开始，保护性耕作土壤有机质含量高于传统耕作，且其土壤有机质含量随土层深度的增加而递减；NPS20、NPS40、NS40、NS20、NSB40和NSB20的春小麦产量较CT分别增产53.08%、46.59%、40.81%、19.93%、17.33%和4.34%。［结论］ 该研究为河西地区发展保护性耕作和维持与培育漠土土壤肥力提供了理论支持。_

English. ［Objective］The purpose was to reveal the effects of different soil tillage patterns on soil fertility. ［Method］ In the field experiment，7 treatments including stubble staying at 20 and 40 cm and overwhelming (NPS20 and NPS40)，stubble staying at 40 and 20 cm and standing (NS40 and NS20)， covering with 6 750 and 3 750 kg/hm2 straw (NSB40 and NSB20) and conventional tillage (CT) were arranged to study the effects of different straw covering amounts， stubble heights and straw treatments on soil organic matter (SOM)， soil microbial biomass carbon (SMB-C) and crop yield. ［Result］The content of SMB-C was highest before spring sowing and lowest after summer harvesting. The soil tillage measure had different effects on SMB-C in different periods. From sowing stage， the SOM content of conservation tillage was higher than that of CT and was gradually decreased as the soil layer depth increased. Compared with CT， the spring wheat yields of NPS20， NPS40， NS40， NS20， NSB40 and NSB20 were increased by 53.08%， 46.59%， 40.81%， 19.93%， 17.33% and 4.34% resp. ［Conclusion］ The study provided some theoretical support for developing conservation tillage and sustaining and cultivating the soil fertility of desert soil in Hexi region. _