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以黑河流域灌区不同保护性耕作作为研究对象,研究保护性耕作农田土壤微生物量的季节变化及剖面分布规律,探讨保护性耕作农田土壤有机质、土壤水分和土壤微生物生物量碳、土壤微生物生物量氮的变化规律,分析影响土壤微生物量的因素。结果表明,保护性耕作明显提高农田土壤有机质、微生物量C和微生物量N含量,且均表现为自上层到下层显著递减的规律。黑河流域农田土壤微生物生物量碳含量平均值为158.06 mg/kg,变幅为35.04～414.34 mg/kg,随季节变化表现为播种期>休闲期>收获期,土壤微生物生物量氮含量平均值为24.73 mg/kg,变幅为9.47～82.87 mg/kg。土壤微生物生物量氮随季节变化也呈现出春秋较高,夏季较低的规律,但季节差异较小。土壤微生物生物量碳对外界环境变化的响应较土壤微生物生物量氮更为敏感,更适宜于作为评价土壤质量快速变化的指标。
Taking the different conservation tillage in the irrigated area of Heihe River Basin as the research object, the seasonal variations and distribution patterns of soil microbial biomass in conservation tillage farmland were studied. The effects of soil organic matter, soil moisture and soil microbial biomass carbon The variation of soil microbial biomass was analyzed. The results showed that conservation tillage significantly increased the contents of soil organic matter, microbial biomass C and microbial biomass N in farmland, and both showed significant decrements from upper layer to lower layer. The soil microbial biomass C content in farmland in Heihe River Basin was 158.06 mg / kg and the amplitude was 35.04 ~ 414.34 mg / kg. The seasons were as follows: sowing period> fallow period> harvest period, mean value of soil microbial biomass nitrogen was 24.73 mg / kg, amplitude range 9.47 ~ 82.87 mg / kg. Soil microbial biomass nitrogen also showed a higher spring and autumn and a lower summer rule with seasonal changes but smaller seasonal differences. The response of soil microbial biomass carbon to environmental changes was more sensitive than that of soil microbial biomass nitrogen, which was more suitable as an indicator to evaluate the rapid change of soil quality.