【摘要】 【目的】本研究明确了长期不同轮作模式下秸秆还田土壤养分周转的关键酶活性因子。【方法】基于成都平原12年长期定位试验,采集水稻-小麦和水稻-油菜轮作模式下秸秆还田和不还田4个处理的耕层((0～20 cm)土样,测定土壤养分与β-GC(β-葡萄糖苷酶)、UR(脲酶)、ACP(酸性磷酸酶)、NAG(β-1,4-乙酰氨基葡萄糖苷酶)和FDA水解酶(荧光素二乙酸酯水解酶)活性,利用冗余分析(RDA)探讨驱动稻田土壤养分周转的关键酶活性因子。【结果】长期水稻-小麦轮作土壤β-GC活性显著低于水稻-油菜轮作,而UR活性水稻-小麦轮作显著高于水稻-油菜轮作(P<0.05)。秸秆还田对耕层土壤中β-GC、UR、ACP和NAG活性影响较小,水稻-小麦秸秆不还田处理土壤FDA水解酶活性显著高于水稻-小麦秸秆还田处理(P<0.05)。除全氮和速效钾外,水稻-小麦轮作土壤pH,有机碳、全磷、全钾、碱解氮和有效磷含量均高于水稻-油菜轮作。长期秸秆还田有利于缓解土壤酸化,提升土壤养分含量。RDA结果显示土壤中β-GC和FDA水解酶受土壤养分影响较大(R~2>0.90,P<0.05)。【结论】轮作模式对β-GC和UR活性影响显著,而秸秆还田对酶活性影响较小,土壤β-GC和FDA水解酶可作为关键酶活性因子表征稻田养分周转。更多还原

【Abstract】 【Objective】The present paper aimed to clarify the key enzyme activity factors of soil nutrient turnover under straw long-term different rotation patterns.【Method】Based on a 12-year long-term positioning experiment in the Chengdu plain, four soil samples were collected under the rice-wheat and rice-rape crop rotation pattern with straw returning to the field and without returning the field, and the β-GC,UR,ACP,NAG and FDA hydrolase activities of soil nutrients were determined.Redundancy analysis(RDA) was used to explore the key enzyme activity factors that drove the turnover of paddy soil nutrients.【Result】Soil β-GC activity under long-term rice-wheat rotation was significantly lower than that under rice-rape rotation, while UR activities showed that rice-wheat rotation was significantly higher than rice-rape rotation(P<0.05).Straw returning had a little effect on the activities of β-GC,UR,ACP and NAG in the topsoil(0-20 cm),while the FDA hydrolase activity of the straw-returning soil under rice-wheat rotation was significantly higher than that of straw not returning the field.In addition to total N and available K,soil pH,organic carbon, total P,total K,available N and available P content were shown as rice-wheat rotation was higher than rice-rape rotation.Long-term straw returning to the field would help alleviate soil acidification and increase soil nutrient content.Results of redundancy analysis(RDA) showed that β-GC and FDA hydrolase in the soil were greatly affected by soil nutrients(R~2> 0.90, P <0.05).【Conclusion】Rotation patterns have a significant effect on β-GC and UR activities, while straw returning to the field has a little effect on enzyme activity, and soil β-GC and FDA hydrolase can be used as key enzyme activity factors to characterize the nutrient turnover in paddy soil.更多还原