本文报道了三江平原低湿耕地综合治理后对土壤微生物生态的影响及对大豆增产的明显效果。4年来开发试验研究的结果表明,低湿耕地经过综合治理并栽培大豆等作物以后,土壤中大豆根瘤菌数量及自生固氮菌的数量明显增加;低湿耕地综合治理后接种高效固氮大豆根瘤菌,经配对选优及结合施用启动氮的高光效高固氮大豆-根瘤菌共生固氮体系的生物技术措施,使大面积的大豆增产12.3％,达到接近岗平地耕作条件下生物技术措施的水平,对今后的生产实践或科学理论都具有重要意义。 This paper reports the effects of integrated management of low and wet farmland on soil microbial ecology in the Sanjiang Plain and its obvious effect on increasing soybean yield. After 4 years of development and experimental studies, the results showed that the number of soybean rhizobia and the number of autotrophic Azotobacter significantly increased after comprehensive management of low and wetland cultivated soils and cultivation of soybean and other crops. After comprehensive treatment of low-humid cultivated land, inoculated with highly efficient nitrogen-fixing soybean rhizobia, The biotechnological measures of optimizing and combining the high-efficiency and high-nitrogen-fixing soybean-rhizobium symbiotic nitrogen fixation system with nitrogen application led to a large-area soybean yield increase of 12.3%, reaching the level of biotechnological measures close to Gangping condition, Practical or scientific theory is of great importance.