中国旱地系统地表植被-土壤状态演化路径识别与过程分析  

Evolution path identification and process analysis of surface vegetation-soilstate in dryland system of China

作　　者：田一禾 焦心 孙强强 孙丹峰 TIAN Yihe;JIAO Xin;SUN Qiangqiang;SUN Danfeng(College of Electrical and Engineering,China Agricultural University,Beijing 100083,China;College of Resources and Environmental Sciences,China Agricultural University,Beijing 100193,China;College of Land Science and Technology,China Agricultural University,Beijing 100193,China)

机构地区：[1]中国农业大学电气与工程学院,北京100083 [2]中国农业大学资源与环境学院,北京100193 [3]中国农业大学土地科学与技术学院,北京100193

出　　处：《测绘通报》2024年第12期149-154,共6页Bulletin of Surveying and Mapping

基　　金：国家自然科学基金(42401130)。

摘　　要：旱地系统作为典型的脆弱生态系统,其地表状态的非线性演化深刻影响着生态平衡与人类福祉,但现有研究尚未全面揭示其复杂的动态演化过程。本文基于2001—2022年逐月植被和土壤地表要素丰度值时间序列产品,采用基于离散小波变换的趋势和转折点检测算法,识别旱地系统植被-土壤状态演化路径并分析其动态变化。结果表明:①2001—2022年,中国旱地系统光合植被和非光合植被端元丰度值都呈显著增加趋势,而土壤生境端元丰度值呈显著减少趋势;②光合植被突然上升、A形上升和V形上升的状态演化路径类型分别占旱地总面积的9.9%、16.8%和21.9%,而非光合植被对应的3种状态演化路径则分别占9.1%、12.6%和28.8%;③整体上旱区的植被恢复促进了土壤裸露的减少,但局部地区水资源匮乏和人类活动导致植被退化。本文为理解中国旱地系统的地表状态演化及其响应机制提供了新视角,并为土地退化监测与生态修复提供了科学依据。As typical fragile ecosystems,dryland systems exhibit nonlinear evolution of their surface states,profoundly affecting ecological balance and human well-being.However,existing studies have yet to fully uncover their complex dynamic evolution processes.Based on monthly time-series products of vegetation and soil endmember fractions from 2001 to 2022,this study employs a trend and breakpoint detection algorithm based on discrete wavelet transform to identify the evolution paths of vegetation-soil states in dryland systems and analyze their dynamic changes.The results indicated that:①From 2001 to 2022,the fractions of photosynthetic vegetation and non-photosynthetic vegetation endmembers in China's dryland systems showed a significant increasing trend,while the fractions of soil endmembers exhibited a significant decreasing trend.②The sudden increase,A-shaped increase,and V-shaped increase state evolution paths for photosynthetic vegetation accounted for 9.9%,16.8%,and 21.9%of the total dryland area,respectively,while the corresponding state evolution paths for non-photosynthetic vegetation accounted for 9.1%,12.6%,and 28.8%,respectively.③Overall,vegetation restoration in dryland had promoted the reduction of soil exposure,but in local areas,water scarcity and human activities had led to vegetation degradation.This study provides a new perspective for understanding the surface state evolution and its response mechanisms in China's dryland systems and offers scientific evidence for land degradation monitoring and ecological restoration.

关 键 词：旱地系统 植被-土壤状态 端元丰度值时间序列 离散小波变换 演化路径 

分 类 号：P208[天文地球—地图制图学与地理信息工程]