荒漠绿洲土壤生态系统结构和功能对景观格局变化的响应及尺度效应

项目名称： 荒漠绿洲土壤生态系统结构和功能对景观格局变化的响应及尺度效应

项目编号： No.41471210

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 地质学

项目作者： 李锋瑞

作者单位： 中国科学院寒区旱区环境与工程研究所

项目金额： 110万元

中文摘要： 在荒漠生态系统，荒漠绿洲过渡带是连接戈壁荒漠、人工绿洲的重要纽带，也是重要的生态缓冲带，对维持人工绿洲生态系统稳定性起着关键作用。近年来人工绿洲扩张导致过渡带景观格局变化已对人工绿洲土壤生态系统环境、结构和功能产生重要影响。然而，尚缺乏对过渡带景观格局变化在不同尺度上影响人工绿洲土壤生态系统环境、结构和功能的研究。本项目以甘肃河西走廊典型人工绿洲为研究对象，采用样带调查、定位观测与建模和理论分析等方法，拟在不同时间（季节、年际）和空间（样方、景观）尺度上系统研究和定量评估过渡带景观格局变化对人工绿洲土壤生态系统环境、结构（土壤食物网组成及其多样性）和功能（如碳和养分循环与积累）的影响，从多层面解析景观格局变化与土壤生态系统环境、结构和功能演变之间的耦合关系及互馈机制。研究成果将提升对人工绿洲生态系统响应高强度人类活动系统行为的预测能力，并为人工绿洲景观格局优化设计和调控提供新知识和新思路。

中文关键词： 全球变化；土壤动物多样性；土壤动物功能；土壤节肢动物；跳虫

英文摘要： In temperate desert ecosystems in Northwest China, the ecotone between desert and oasis is thought to be an important link between desert and oasis ecosystems as well as an ecological buffer zone in which plays a key role in maintaining the stability of the oasis ecosystem. In recent decades, the human-induced rapid expansion of artificial oases in desert landscape has led to changes in landscape patterns in the desert-oasis ecotones,with consequences of fragmentation of native desert landscape into small and isolated patches consisted of farmland as well as woodland and shrubland plantations. This landscape pattern change in turn causes substantial alterations in the environment, structure, and functions of soil ecosystems. However, how changes in landscape patterns through replacement of natural desert landscape with different land use types such as farmland and shrub/tree plantations affect the soil ecosystem environment, structure, and functions is poorly understood. Using a typical artificial oasis habitat in the Hexi Corridor, Gansu province, northwestern China, we assess the scale-dependent responses of the soil ecosystem environment, structure, and functions to changes in landscape patterns. The main objectives of this study are to quantify: (1) the effects of landscape pattern changes on soil biological, chemical, and physical conditions of the oasis ecosystem; (2) the effects of landscape pattern changes on soil food web composition, abundance, and diversity of the oasis ecosystem; (3) the effects of landscape pattern changes on the functioning and services of soil ecosystems; and (4) the mechansims underlying how differences in soil food web composition and abundance resulting from changes in landscape patterns affect the functioning of soils and the ecosystem services that they deliver. Understanding the influence of landscape change on the soil food web composition and the ecosystem functions by altering vegetation type, microclimate, and soil physical-chemical-biological properties as well as quantifying general associations between soil biota and ecosystem functions may have important implications for the development of appropriate land use management strategies for conserving soil biodiversity and ecosystem functioning in this desert oasis ecosystem.

英文关键词： Global change;soil fauna diversity;soil fauna functions;soil arthropods;Collembola