| 摘要: |
| 【目的】分析黄河流域NDVI时空变化特征，探究NDVI对陆地水储量（TWSA）的响应关系。【方法】基于GIMMS NDVI和GRACE TWSA遥感数据，采用Theil-Sen趋势分析、M-K趋势检验、相关分析，分析了2002—2015年黄河流域生长季植被NDVI变化特征及其对TWSA的响应。【结果】2002—2015年黄河流域生长季植被年NDVI均值为0.4156，总体上呈波动上升趋势，增速为0.35%/a，个别年际变化波动性较大。空间分布上，黄河流域NDVI表现出较强的差异特征，整体上由东南向西北呈带状递减分布。植被NDVI显著上升的区域主要分布在黄河流域中部的陕西省、山西省以及甘肃省南部，植被NDVI显著下降区域零星分布于流域南部及下游区域，流域大部分区域NDVI呈缓慢增加趋势。植被NDVI和TWSA的响应呈显著的空间差异性，呈正相关的区域主要分布在黄河上游的三江源地区、甘肃和宁夏的南部、内蒙古东部等地区。【结论】植被NDVI和TWSA在上游三江源区和甘肃南部呈显著正相关，而在中下游地区相关性则不明显甚至呈负相关，一方面这是由黄河流域的水热条件导致的，中上游降水稀少，此时TWSA对植被的影响较大；另一方面人类活动的加入使这些地区TWSA和植被NDVI的相关性减弱甚至呈负相关。 |
| 关键词: NDVI；TWSA；时空变化；相关分析；黄河流域 |
| DOI： |
| 分类号:P962 |
| 基金项目:国家自然科学基金项目(No.41961057)、内蒙古自治区高等学校青年科技英才支持计划项目(NJYT-17-B04)联合资助。 |
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| Variation characteristics of NDVI in the Yellow River Basin from 2002 to 2015 and its response to terrestrial water storage |
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yuanruiqiang, qingsong
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Inner Mongolia Normal University
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| Abstract: |
| 【Background】Vegetation is one of the most important components of the terrestrial ecosystem. It has the function of connecting the ecological elements such as the atmosphere, soil and hydrology, and can provide a strong guarantee for the natural ecosystem and human production and life. The spatial and temporal changes of vegetation will cause changes in surface parameters, which will affect the balance of energy and water on the surface. At present, monitoring and analysis of influencing factors for long-term vegetation changes has become an important content of global change research, and can provide a scientific basis for regional ecological environmental protection and sustainable development.【Objective】Analyze the temporal and spatial changes of NDVI in the Yellow River Basin, and explore the response of NDVI to terrestrial water reserves (TWSA).【Method】Based on GIMMS NDVI and GRACE TWSA remote sensing data, the Theil-sen trend analysis, M-K trend test, and correlation analysis were used to analyze the NDVI change characteristics and its response to TWSA during the growing season of the Yellow River Basin from 2002 to 2015.【Results】The average annual NDVI of the vegetation in the growing season of the Yellow River Basin from 2002 to 2015 was 0.4156, which generally showed a rising trend with a growth rate of 0.35%/a. The individual interannual changes were relatively volatile. In terms of spatial distribution, the NDVI of the Yellow River Basin showed strong differences, and the overall distribution decreased from southeast to northwest. The areas where vegetation NDVI increased significantly were mainly distributed in the Loess Plateau region of the Yellow River Basin. The areas where vegetation NDVI decreased significantly were scattered in the southern and downstream areas of the watershed. Most areas of the watershed increased NDVI as the main trend. The responses of vegetation NDVI and TWSA showed significant spatial differences, and the areas that were positively correlated were mainly distributed in the Sanjiangyuan region of the upper Yellow River, southern Gansu and Ningxia, and eastern Inner Mongolia.【Conclusion】TWSA has a greater correlation with vegetation in the upstream and middle reaches of the region, while the correlation in the middle and lower reaches is not obvious or even negatively related. On the one hand, this is caused by the water and heat conditions in the Yellow River Basin, and the areas with rare precipitation in the middle and upper reaches At this time, TWSA has a greater impact on vegetation; on the other hand, the change of vegetation NDVI is not only affected by TWS, but the role of human activities cannot be ignored. |
| Key words: NDVI; TWSA; temporal and spatial changes; correlation analysis; Yellow River Basin |
