土地利用／覆盖变化与生态系统管理被认为是人类活动影响陆地生态系统地上／地下生态过程最重要和最直接的两个因素。目前，针对中国西北干旱区荒漠绿洲生态系统，关注土地利用／覆被变化与土地管理措施对土壤动物群落演变过程及其多样性形成的耦合影响与调控机制的综合性研究甚少。
中国科学院寒区旱区环境与工程研究所科研人员以黑河中游人工绿洲边缘天然草地及其转变的人工梭梭灌木林（21a）、人工杨树林（28a）、人工樟子松林（33a）和农田（开垦27a和100a）为研究对象，基于6种研究样地中小型土壤动物群落的调查数据，采用多变量排序和通径分析等方法，研究了土地利用／覆被变化与管理措施对中小型土壤动物群落及其主要类群演变的耦合效应。
研究表明：①将天然草地转变为未实施管理措施的人工梭梭灌木林后并未引起土壤动物群落组成、数量和物种多样性的显着变化，而转变为实施管理措施的杨树和樟子松人工林及农田后，导致了土壤动物群落组成、数量和物种多样性的变异，证实了土地覆被变化对中小型土壤动物群落的作用及其效应受管理措施的强烈调控。
②土壤动物群落的演变过程受土地覆被变化与灌溉和施肥管理的共同影响，其中灌溉的贡献率最大，是关键驱动因子。
③不同土壤动物类群对土地覆被变化和管理耦合作用的响应不同。灌溉对跳虫、甲螨和革螨的个体数量和物种丰富度的直接影响和总效应最大；施肥对辐螨的个体数量和物种丰富度的直接影响和总效应最大；灌溉和施肥对稀有类群的个体数量和物种丰富度的直接影响和总效应均较大，具同等重要的作用。
研究表明：土地覆被变化与管理耦合作用通过改变土壤水文和生态环境条件驱动了中小型土壤动物群落的演变过程。
该研究对于深入认识和理解人类活动影响下干旱荒漠绿洲生态系统的水、土、生相互作用关系及生态系统的结构与功能的演变方向，具有重要科学意义和实际应用价值。
本研究项目受到国家自然科学基金项目（91025021，31170496）、国家重点基础研究发展计划“973”项目（2009CB421302）和城市与区域生态国家重点实验室开放基金（SKLURE2009-2-3）共同资助；研究成果发表于《中国沙漠》。(生物谷Bioon.com)
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The Combined Effects of Land-cover Change and Management Practices on Soil Microfauna Communities
LI Feng-rui,LIU Ji-liang,LIU Chang-an,NIU Rui-xue,LIU Qi-jun
In this study，we investigated soil microfauna communities across six major land－use/cover typesof natural grassland and 5 differently managed artificial systems（21－year－old planted shrubland，28－year－oldPoplar and 33－year－old Pinus plantations，and 27－and 100－year－old croplands）converted from naturalgrassland in an arid region of northwest China．The data were used to quantify the combined effects of landcover change and management disturbances on the dynamics of soil microfauna communities．The conversionof natural grassland to unmanaged planted shrubland did not cause a significant change in the structure of themicrofauna community，while the conversion of natural shrubland to managed Poplar and Pinus plantationsand croplands significantly increased abundance，richness and diversity of the microfauna community．Multivariate and path analyses showed that the assembly of soil microfauna communities was significantly affectedby the combination of land－cover change（indicated by vegetation cover），irrigation and fertilization，but theirrigation disturbance was the most important driver．The response of soil microfauna to irrigation，fertilization and vegetation cover varied among different components of the assemblages．Overall，irrigation had thegreatest contribution to observed variation in the abundance and species richness of Collembola，Oribatidaand Gamasida，while fertilization was more important than irrigation and vegetation cover to variation in theabundance and species richness of Actinetidida，and both irrigation and fertilization contributed to variationin the abundance and species richness of the rare group．Our results suggest that land－cover change and management disturbances interact in shaping soil microfauna community dynamics，but irrigation was identifiedto be the most important structuring force in soil fauna communities in this arid environment
