不同耕作措施下秸秆还田对土壤速效养分和微生物量的影响

Effect of Straw Returning on Soil Available Nutrients and Microbe Biomass Under Different Tillage Methods

为揭示西辽河平原玉米秸秆还田的效应,在2014—2015年设秸秆深翻还田(DR)和秸秆旋耕还田(RR)2个处理,以旋耕不还田(CK)为对照,研究了不同耕作措施下秸秆还田当年和次年对土壤速效养分和微生物量的影响。结果表明:DR和RR均能不同程度的提高土壤碱解氮、速效钾的含量和细菌、真菌、放线菌的数量,且DR较RR的效果更为明显,RR对土壤有效磷含量影响不大。秸秆还田次年完熟期,3个土层(0—10,10—20,20—30cm)的平均值,土壤碱解氮含量DR和RR分别较CK增加了26.60%,16.34%,有效磷含量分别增加了19.81%,0.92%,速效钾含量分别增加了23.95%,12.53%,3个土层的总计,细菌数量分别增加36.46%,9.80%,真菌数量分别增加了22.10%,21.90%,放线菌数量分别增加23.55%,17.38%。秸秆还田当年与次年相比,土壤速效养分除拔节期当年增长幅度低于次年外,其他各时期均表现为当年增长幅度高于次年,微生物量表现为次年增长幅度高于当年;秸秆还田与对照相比,土壤速效养分和微生物量的增加,主要表现在0—10cm土层;不同生育时期相比,土壤速效养分还田当年以完熟期最大,次年以拔节期最大。

From 2014 to 2015,set deep plowing with straw returning（DR）and rotary tillage with straw returning（RR）,took rotary tillage without straw returning（CK）as the control,studied effect of current year and the following year with straw returning on soil available nutrients and microbial biomass under different tillage methods at Plain of Xi Liao River.The results showed that deep tillage with straw returning and rotary tillage with straw returning all could increase in various degrees of soil available nitrogen,potassium content and bacteria,fungi,actinomycetes number,straw returning with deep plowing had more obvious effect,the rotary tillage with straw returning had little effect on soil available phosphorus content.Straw returning the following year,according to average for 3different soil layers（0—10,10—20,20—30cm）at full ripe stage,compared with CK,the content of available nitrogen in DR and RR increased by 26.60%and 16.34%respectively,available phosphorus increased by 19.81% and 0.92%,available potassium increased by23.95% and 12.53%,according to total of 3different soil layers,the number of bacteria increased by36.46% and 9.80%,the number of fungi increased by 22.10% and 21.90%,the number of actinomycetes increased by 23.55% and 17.38%.Compared with the current year and the following year,the growth rate of soil available nutrient was higher than that in the current year at jointing stage,and the growth rate of other periods was higher than that in the following year,the microbial biomass performance for the following year growth rate was higher than that in the current year.Compared with the control,the soil available nutrients and microbial biomass increased mainly in the 0—10cm soil layer.Compared with the different growth stages,the soil available nutrients performance for full ripe stage was the biggest at the current year,and the following year at the jointing stage was the biggest.