保护性耕作改善东北农田黑土土壤生物多样性及其生态功能

Conservation Tillage Improves Soil Biodiversity and Its Ecological Function in the Black Soil Region of Northeast China

保护性耕作是攻克黑土地保护和利用的核心技术之一。研究立足中国科学院黑土区农业生态重点试验室保护性耕作长期定位试验基地,系统梳理总结了农田黑土土壤生物多样性对保护性耕作的响应特征。与传统耕作相比,保护性耕作显著增加各生物类群(微生物、线虫、跳虫、螨类及蚯蚓)的物种丰富度(1%~8%)、数量(25%~57%)和生物量(30%~50%),提高食物网网状结构的复杂性及各营养级间的连通性(14%~32%),促进土壤生物在固土蓄水、土壤碳固存、氮素高效利用以及稳定作物产量四方面生态功能的可持续性发挥。研究结果表明,实施保护性耕作可有效利用土壤生物的功能潜力,实现东北黑土区农田生态系统的健康发展、服务国家粮食安全产业带建设和现代农业发展。

Conservation tillage has become the core technology to conquer the degradation of black soil.Since soil is a home to a variety of organisms,it is very important to regard soil as a living system to evaluate the impact of conservation tillage on the health of black soil.Therefore,based on the long-term conservation tillage trial established by the Key Laboratory of Mollisols Agroecology of the Chinese Academy of Sciences,the responses of soil biodiversity and its function to conservation tillage were comprehensively elucidated in this study.Compared with conventional tillage,conservation tillage strongly improved the species richness(1%-8%),density(25%-57%),and biomass(30%-50%)of the entire soil assemblages,including microorganisms,nematodes,collembolans,mites and earthworms,as well as the connectance of soil food web(14%-32%).Furthermore,conservation tillage promotes the performance of soil biotic function in soil structure formation,soil carbon sequestration,nitrogen efficient utilization and crop yield stability.These results suggest that conservation tillage can effectively utilize the functional potential of soil organisms,which is of great significance to supporting the healthy and sustainable development of agriculture in the black soil region of Northeast China.