珠江三角洲农业土壤重金属污染多尺度分异及其景观异质性机制

项目名称： 珠江三角洲农业土壤重金属污染多尺度分异及其景观异质性机制

项目编号： No.41501203

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 天文学、地球科学

项目作者： 李铖

作者单位： 广东省生态环境技术研究所

项目金额： 24万元

中文摘要： 土壤重金属污染本质上是元素在不同景观单元间的迁移扩散过程，其空间累积与景观异质性相关联，并具有明显尺度特征，认识和理解这种时空尺度特征是解析土壤污染的重要途径。相对于较为普遍的单一或小尺度研究，土壤污染多尺度研究因土壤连续观测难度及其有效样本量而一直是研究的难点。本项目以人类活动较强、污染问题较为突出的珠江三角洲农业土壤为研究对象，基于2005年和2015年两个时间尺度，采用遥感与GIS、空间分析、野外实验调查等方法，研究土壤重金属污染的多尺度分异规律。以此为基础，应用景观生态学方法，在土壤重金属污染格局上叠加不同景观异质性因子，进行多尺度关联分析，进一步解析重金属污染时空分异的景观异质性机制。研究成果将为土壤重金属污染研究提供景观生态学方法和途径，为土壤污染防治及其宏观生态决策提供科学依据。

中文关键词： 农业土壤污染；重金属；景观异质性；多尺度；珠江三角洲

英文摘要： Soil heavy metal contamination is essentially a diffusion process of heavy metals among different landscape components. Thus, the heavy metal accumulation is influenced by the spatial variation of the composition and configuration of landscapes (i.e., landscape heterogeneity) and the influence varies at different scales. Understandings and solutions to environmental problems entail unravelling the scale-dependent interactions between landscape heterogeneity and soil contamination. However, most soil studies have been conducted on single or fine scales. A multiple-scale study is a challenge due to the non-continuous and limited numbers of soil samples especially at coarser scales. In this project, we quantified the spatiotemporal pattern of agricultural soil contamination in the Pearl River Delta region, one of regions with strong human activities and serious environmental problems in China from 2005 to 2015, based on methods such as remote sensing, GIS, spatial analysis and field experiments. We further explore the mechanisms how landscape heterogeneity at different scales affects soil contamination, by correlating them over a range of scales (grain size) using a series of approaches in landscape ecology. Information gained from this project would help build up landscape ecological framework for guiding soil research designs, providing theoretical basis for soil pollution prevention and remediation as well as region-level environmental management in south China.

英文关键词： agricultural soil contamination;heavy metal;landscape heterogeneity;multiple scales;Pearl River Delta