2001—2021年黄河流域植被覆盖变化及其驱动因素

Changes in vegetation cover and driving factors in the Yellow River Basin from 2001 to 2021

黄河流域作为中国重要的生态屏障和经济走廊,揭示其植被覆盖变化的响应机制,有利于促进生态、经济和社会的协调发展。本文基于MOD13A3、气候和经济数据,采用趋势分析和相关分析法分析黄河流域2001—2021年植被覆盖变化特征,探究气候与人类活动对植被的影响机制。结果表明:(1)2001—2021年,研究区植被覆盖增加速率为0.35%·a^(-1),81.33%的地区植被覆盖呈增长趋势,关中平原与中原城市群植被发生退化。(2)时间尺度上,黄河流域NDVI对气候和人类活动的响应存在滞后性;空间尺度上,NDVI与降水和气温表现为正相关,NDVI对降水的响应集中在200mm等降水量线,对气温的响应分布在高原亚寒带、中温带地区。人类经济活动对NDVI的影响以正相关为主,其中NDVI与第一产业呈正相关,与第二产业呈负相关,面积占比分别为51.45%和7.47%。(3)黄河流域植被变化受气候和人类活动的双重影响,其中人类经济活动因子驱动面积占比55.25%,占据主导地位,表明经济发展等人类活动对植被的生长和分布影响显著,超过了降水和气温变化的作用。

As an important ecological barrier and economic corridor in China,the study of the Yellow River Ba-sin reveals the response mechanism of vegetation cover change,which is conducive to promoting the coordinated development of ecology,economy,and society.Based on MOD13A3 climate and economic data,this paper uses trend analysis and correlation analysis to determine the characteristics of vegetation cover change in the Yellow River Basin from 2001 to 2021,and explores the mechanisms of impact of climate and human activities on vege-tation.The results show that:(1)From 2001 to 2021,the rate of vegetation cover increase in the study area was 0.35%·a^(-1),and the vegetation cover in 81.33%of the area followed an increasing trend.(2)On the time scale,the NDVI response to climate and human activities in the Yellow River Basin lags;on the spatial scale,NDVI is posi-tively correlated with precipitation and temperature.NDVI’s response to precipitation is concentrated in the 200 mm precipitation line,and its response to temperature is distributed in the plateau subarctic zone and the middle temperate zone.The impact of human economic activities on NDVI was a predominantly positive correlation,among which NDVI was positively correlated with the primary industry and negatively correlated with the sec-ondary industry,accounting for 51.45%and 7.47%of the total area,respectively.(3)The vegetation change in the Yellow River Basin is affected by both climate and human activities.The area affected by human economic activi-ty factors comprised 55.25%of the total area,which was a majority,indicating that human activities,such as eco-nomic development,have a significant impact on the growth and distribution of vegetation that exceeds the ef-fects of precipitation and temperature changes.