不同腐秆剂施用对安徽沿淮稻田土壤养分及活性有机碳库的影响

Impact of various straw-decomposing inoculant on soil nutrients and labile organic carbon pool in paddy field

为探明安徽沿淮地区麦秆粉碎还稻田时配施不同的腐秆剂对土壤养分以及活性有机碳的影响,遴选出适合该区域使用的腐秆剂,通过安徽省霍邱县的秸秆促腐还田定位试验,比较了秸秆还田+优化平衡施肥+不施腐秆剂(SF)、秸秆还田+优化平衡施肥+腐秆剂1号(SFD1)、秸秆还田+优化平衡施肥+腐秆剂2号(SFD2)和秸秆还田+优化平衡施肥+腐秆剂3号(SFD3)4个处理在耕层土壤养分、总有机碳、活性有机碳、微生物生物量碳、不同形态碳素有效率和碳库管理指数等方面的差异。结果表明,配施腐秆剂处理中SFD1和SFD2的土壤碱解氮含量显著高于不施腐秆剂处理SF(P<0.05),分别增加了14.3%和15.6%;SFD1和SFD2处理较SF处理活性有机碳、微生物生物量碳、活性有机碳有效率和微生物生物量碳有效率分别显著提高了18.8%、48.0%、6.5%、33.3%和18.0%、51.0%、5.2%、37.5%(P<0.05),SFD3较SF处理微生物生物量碳及有效率显著降低了52.2%和41.7%(P<0.05);配施腐秆剂SFD1和SFD2处理的土壤碳库管理指数(CPMI)值整体显著高于不施腐秆剂处理SF,均增加了22.4%(P<0.05);土壤总有机碳能够表征土壤养分及碳素动态变化。综上可知,安徽沿淮稻田秸秆还田配施1号或2号腐秆剂均有利于提高土壤养分,提升土壤碳库管理指数。

This study investigated the impact of the different straw-decomposing microorganism inoculant(SDMI)on soil nutrients and labile organic carbon pool in paddy field under smash returning in regions along the Huai river in Anhui,so as to provide a theoretical basis for reasonable application.Four treatments were designed,which included straw returning with optimized NPK fertilization then applied SDMI No.1(SFD1),or SDMI No.2(SFD2),or SDMI No.3(SFD3)or nothing(SF),and the differences among them in soil nutrients,total organic carbon(TOC),labile organic carbon(LOC),microbial biomass carbon(MBC),available labile organic carbon(ALC),available microbial biomass carbon(AMC)and carbon pool management index(CPMI)were contrasted.The results showed that SFD1 and SFD2 both increase soil alkalystic nitrogen,LOC,MBC,ALC and AMC by 14.3%,18.8%,48.0%,6.5%,33.3%and 15.6%,18.0%,51.0%,5.2%,37.5%,respectively.However,SFD3 significantly reduced the MBC and AMC by 52.2%and 41.7%,when compared with SF.In addition,SFD1 and SFD2 both increased CPMI by 22.4%,respectively.The correlation test indicated that TOC could objectively reflect changes in soil nutrients and soil carbon dynamic.In conclusion,the application of different SDMIs can increase soil nutrients and promote labile organic carbon,and the effects of SDMI No.1 and SDMI No.2 are more obvious.