秸秆覆盖的免耕耕作措施可有效遏制土壤退化，对秸秆资源合理利用及耕地质量提升具有重要意义。探索外源输入碳在线虫-微生物群落间的转化途径及对微生物残留物贡献土壤有机质的影响是亟待解决的科学问题。本研究以东北典型农田土壤为对象，依托免耕秸秆覆盖长期定位试验平台，将分子/群落水平的微生物特征分析和传统的线虫群落鉴定手段相结合，探究线虫-微生物碳通道对微生物残留物积累的调控机制。采用磷脂脂肪酸、高通量测序、微生物酶活、氨基糖以及线虫群落组成和碳代谢足迹等技术及分析方法，结合线性分析和结构方程模型，旨在：1）厘清不同量和频率的秸秆覆盖对土壤线虫和微生物生物量、群落组成和功能的影响；2）阐明微生物残留物对线虫-微生物群落互作的响应；3）评价细菌和真菌能量通道对土壤有机碳形成及稳定的相对贡献和影响机理。本研究为调控土壤有机碳周转和农田可持续生产及高效管理提供理论及实践依据。

Stover mulching and no tillage can effectively reduce soil degradation, which has great significance for the rational utilization of stover and improvement of cultivated land quality. It is an urgent scientific problem to explore the transformation pathway of stover-derived carbon between nematode-microbial communities and the contribution of microbial residues to soil organic matter. This research focus on typical agriculture soil in northeast China, investigates in long time no tillage and stover mulching research platform. Microbial feature analysis in molecular level combined with traditional nematode community identification to study the regulation mechanism of nematodes-microorganisms carbon channel on microbial residues accumulation. We use phospholipids fatty acids analysis (PLFA), DNA sequencing technique (MiSeq), microbial metabolic activity, amino sugar, soil nematode community and metabolic footprint analysis, and combining with linear analysis and structural equation model, for 1) identifying how different amount and frequency of stover mulching affect soil microbivore nematodes, microbial community biomass, composition and function. 2) illustrating the response of microbial residues to nematode-microbial community interaction. 3) evaluating relative contribution and mechanism of bacterial and fungal energy channels to the formation and stabilization of soil organic carbon. Ultimately, this study provides theoretical basis and practical support for the regulation of soil organic carbon turnover, sustainable development and efficient management of farmland.