毛乌素沙地植被净初级生产力时空变化及其驱动因素

Spatial and Temporal Changes of Vegetation Net Primary Productivity and Its Driving factors in Mu Us Sandy Land

净初级生产力(Net primary productivity,NPP)及其对全球气候变化的响应是全球变化研究的热点之一。本研究基于MODIS遥感数据、DEM数据和气象数据等,采用Sen趋势分析、MK显著性检验、CV稳定性分析、偏相关与多元回归分析等方法,分析毛乌素沙地植被NPP的时空变化规律,并定量分析气候变化对植被NPP的影响机制。结果表明:2001—2022年毛乌素沙地植被NPP年均值变化范围介于102.75~210.62 g·m^(-2)之间。整体上,植被NPP呈现波动上升趋势,但是存在明显差异。空间上,毛乌素沙地植被NPP年平均值为164.43 g·m^(-2),植被NPP呈增加趋势的区域分布在北部,呈减少的区域位于南部。在毛乌素沙地东部对植被NPP的影响中,辐射是主导因素之一;在西部与中部,温度和降水是主导因素之一。研究表明气候因素对毛乌素沙地植被NPP的变化有显著作用,其结果也为研究区的生态绿色建设与资源的开发提供科学依据。

Net primary productivity(NPP)and its response to global climate change is one of the hotspots in global change research.In this study,based on MODIS remote sensing data,DEM data and meteorological data,we analyzed the temporal and spatial variation pattern of vegetation NPP in Mu Us Sandland by using the methods of Sen trend analysis,MK significance test,CV stability analysis,bias correlation and multiple regression analysis,etc.,and quantitatively analyzed the mechanism of climate change impact on vegetation NPP.The results showed that the annual mean values of vegetation NPP in Mu Us Sandland varied between 102.75 and 210.62 g·m^(-2)from 2001 to 2022.Overall,the vegetation NPP showed a fluctuating upward trend,but there were obvious differences.Spatially,the annual mean value of vegetation NPP in the Mu Us Sandland was 164.43 g·m^(-2),and the area with an increasing trend in vegetation NPP was distributed in the north,and the area with a significant decrease was located in the south.Radiation was one of the dominant factors in the influence of vegetation NPP in the eastern part of the Mu Us Sandy land,and temperature and precipitation were two of the dominant factors in the western and central regions.The study shows that climatic factors play a significant role in the changes of vegetation NPP in the Mu Us Sandland,and the results also provide a scientific basis for the ecological green construction and resource development in the study area.