1982-2020年乌兰县植被NPP时空动态特征及驱动力量化分析OA北大核心CSTPCD
Quantitative analysis of the spatiotemporal dynamics and driving forces of vegetation NPP in Wulan County of China from 1982 to 2020
气候变化和人类活动对植被NPP(net primary productivity,净初级生产力)的驱动作用是全球气候变化背景下的研究热点,并且在不同的时空尺度上尚不能达成共识.中国西北寒旱牧区植被生态系统脆弱,对气候变化和人类活动的响应十分敏感,该研究以青海省乌兰县作为代表性研究区,采用GIMMS-NDVI and MOD-NDVI数据融合构建了长时序归一化植被指数(normalized difference vegetation index,NDVI)数据集,并结合 CASA(carnegie-ames-stanford approach)模型获取了研究区 1982-2020年植被生长季NPP,利用Sen+MK趋势分析方法探究了研究区植被生长季NPP的时空演变特征,同时采用构建的ADE+Sen量化归因方法对多种气候要素和人类活动的驱动作用进行了定量分析.结果表明,研究区植被生长季NPP多年均值为(205.9±11.5)g/(m2·a)(以C计),年际变化无显著趋势,不同植被类型的生长季NPP年际波动过程与全域生长季NPP基本一致.在空间上,植被生长季NPP自西向东逐渐增加,年际变化趋势具有明显的空间异质性,且整体以退化为主,平均变化率为-0.151 g/(m2·a2),其中表现出严重退化和轻度退化的面积占比分别达到了 31.7%和 29.5%.气候变化主导的植被面积占比达 85.2%,其贡献值的绝对平均值为 1.025 g/(m2·a2),约是人类活动贡献值绝对平均值的 2倍,太阳辐射、降水量、平均气温和平均风速均是影响植被生长季NPP动态的主要气候因素.该研究表明研究区植被整体表现为退化状态,气候变化是导致该现象的主导驱动因素.研究结果可为中国西北寒旱牧区植被生态系统的可持续利用和保护提供参考.
The driving effects of climate change and human activities on vegetation NPP(net primary productivity)is known as a research hotspot in the context of global climate change,of which the consensus cannot be reached at different spatiotemporal scales.The vegetation ecosystem in cold and arid pastoral areas of northwest China is fragile and highly sensitive to climate change and human activities.In this study,Wulan County,Qinghai Province was taken as the representative study area.Based on the long sequence NDVI(normalized difference vegetation index)dataset constructed by GIMMS-NDVI and MOD-NDVI,combined with the CASA(carnegie-ames-stanford approach)model,the vegetation growing season NPP of the study area from 1982 to 2020 was obtained.The spatiotemporal evolution characteristics of growing season NPP in the study area over the past 40 years were explored using the Sen+MK method,and then the proposed quantitative attribution method of ADE+Sen was used to quantitatively identify the driving forces of different climate factors and human activities to the dynamics of growing season NPP.The results showed that the annual mean of growing season NPP in the study area was(205.9±11.5)g/(m2·a)(measured in C),and the interannual variation of growing season NPP had no significant trend.The interannual variation of growing season NPP for different vegetation types was basically consistent with the regional growing season NPP.Over the space,the multi-year mean of growing season NPP gradually increased from west to east.The change patterns of growing season NPP exhibited significant spatial heterogeneity and were mainly characterized by degradation with the average rate of-0.151 g/(m2·a2).The areas with severe and slight degradation accounted for 31.7%and 29.5%,respectively.Climate change was the dominant driving factor for the dynamics of growing season NPP,with a dominant vegetation area accounting for 85.2%.The absolute average value of the contribution of climate change was 1.025 g/(m2·a2),which was nearly twice the absolute average value of the contribution of human activities.Solar radiation,precipitation,average temperature,and average wind speed were the main climate factors affecting the dynamics of growing season NPP.In conclusion,the vegetation in the study area was mainly in a degraded state,and climate change was the dominant driving factor leading to this phenomenon.The findings can provide reference for the sustainable utilization and protection of vegetation ecosystem in cold and arid pastoral areas of northwest China.
刘辉;宋孝玉;王荣荣;祝德名;何希;刘斯琪
西安理工大学省部共建西北旱区生态水利国家重点实验室,西安 710048河南大学土木建筑学院,开封 475004
生物学
净初级生产力气候变化人类活动定量分析乌兰县
net primary productivityclimate changehuman activitiesquantitative analysisWulan County
《农业工程学报》 2024 (003)
328-334 / 7
国家重点研发计划项目(2016YFC0400301);陕西省自然科学基础研究计划项目(2023-JC-ZD-30);西安理工大学博士创新基金项目(310-252072114)
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