耕作方式及秸秆还田对土壤性质、微生物碳源代谢及小麦产量的影响

Effects of tillage methods and straw return on soil properties, metabolism of microbial carbon source and wheat yield

以小麦品种济麦22为试验材料,采用裂区试验设计,耕作方式为主区,分别设常规翻耕(C)、深松(S)、旋耕(R)处理,副区为秸秆还田量,分别设秸秆全还田(P)和秸秆不还田(A)处理,采用Biolog Eco技术测定土壤微生物碳源代谢功能,并分析土壤基本理化性质和作物产量。结果显示:深松与秸秆还田均有利于土壤含水量和有机碳含量的提高,0~15 cm土层分别提高了9.78%和24.00%,15~30 cm土层分别提高了7.08%和15.81%;深松提高了15~30 cm土层的pH值6.67%,秸秆还田提高了0~15 cm土层的pH值4.32%。深松和秸秆还田均有利于代谢多样性(丰富度指数、香浓多样性指数)、碳源代谢强度的提高,0~15 cm土层分别提高了26.84%、3.84%和38.02%,15~30 cm土层分别提高了11.87%、3.63%和14.74%。主成分分析表明常规翻耕秸秆不还田和旋耕耕作秸秆不还田碳源代谢功能相近,15~30 cm层次内常规翻耕秸秆全还田碳源代谢功能和深松耕作秸秆全还田处理相近。深松和秸秆还田平均提高了小麦产量5.82%,微生物碳源代谢功能与小麦产量具有极显著的相关性。

Using wheat 22 as test material,this experiment adopted a split-plot design,with tillage methods as main treatments including conventional tillage(C),subsoiling(S)and rotary tillage(R),with straw returning amount as sub treatments including straw returning(P)and no straw returning(A).We used Biolog Eco technology to measure metabolism function of carbon source of soil microorganisms,and analyzed basic physical and chemical properties of soil and crop yield.The results showed that,subsoiling and straw returning significantly enhanced soil water and organic carbon content,with 0~15 cm soil layers increased by 9.78%and 24.00%,15~30 cm soil layers increased by 7.08%and 15.81%,respectively.Also,subsoiling increased the pH in 15~30 cm soil layer by 6.67%,and straw returning increased the pH of 0~15 cm soil layer by 4.32%.Subsoiling and straw returning significantly increased the metabolic diversity(richness index,aroma diversity index)and carbon metabolism intensity,0~15 cm soil layer increased by 26.84%,3.84%and 38.02%,and 15~30 cm soil layer increased by 11.87%,3.63%and 14.74%,respectively.Principal component analysis showed that the metabolic functions of carbon source between AC and AR were similar,and the metabolic functions of carbon source between PC and PS were similar in 15~30 cm soil layer.Both subsoiling and straw returning significantly increased wheat yield by 5.82%on average,and the microbial carbon metabolism function had a very significant correlation with wheat yield.