| 摘要: |
| 【目的】分析黄河流域NDVI时空变化特征，探究NDVI对陆地水储量距平（TWSA）的响应。【方法】基于GIMMS NDVI和GRACE TWSA遥感数据，采用Theil-Sen趋势分析、M-K趋势检验和相关分析研究了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0.42，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显著正相关，而在中下游地区相关性则不明显甚至负相关，这是由黄河流域的水热条件和人类活动影响导致的。 |
| 关键词: 植被指数（NDVI）；陆地水储量距平（TWSA）；时空变化；相关分析；黄河流域 |
| DOI：10.13522/j.cnki.ggps.2020390 |
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| Response of the Normalized Difference Vegetation Index to Water Storage in Terrestrial Basin of the Yellow River Basin: Taking 2002-2015 as an Example |
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YUAN Ruiqiang, QING Song
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1.College of Geographical Science, Inner Mongolia Normal University, Hohhot 010022, China;2.Key Laboratory of Remote Sensing and Geographic Information System, Hohhot 010022, China
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| Abstract: |
| 【Background】Vegetation is one of most important components in the terrestrial ecosystem, connecting atmosphere, soil and hydrological processes. Spatiotemporal changes in vegetation could affect the balance of energy and water cycling; measuring and analyzing the factors that have a long-term impact on vegetation dynamics has been in increase globally as they are crucial to helping protect ecological system functions and sustain regional development.【Objective】The objective of this paper is to analyze the spatiotemporal change in the normalized difference vegetation index (NDVI) in the Yellow river Basin, and elucidate its response to change in terrestrial water storage anomaly (TWSA).【Method】The analysis was based on the GIMMS NDVI and GRACE TWSA retrieved from remote sensing data, and the Theil-sen trend analysis, M-K trend test and correlation analysis were used to analyze the change of NDVI in response to TWSA from 2002 to 2015 in the basin.【Result】The average annual NDVI during the crop growth season in the studied period was 0.42, but rising at an annual rate of 0.35%. The NDVI varied significantly over space, decreasing from the southeast to the northwest. Areas showing significant increase in NDVI are in Shaanxi, Shanxi and southern Gansu, all in the middle reach of the river. In contrast, areas showing significant decline in NDVI are in the southern areas in the lower reach of the river. Overall, NDVI has seen an increase in most areas and its response to TWSA varied significantly over space, with a positive correlation found in the Three River Source region, southern Gansu and Ningxia, as well as eastern Inner Mongolia.【Conclusion】TWSA showed a strong positive correlation with the vegetation in the upstream and middle reaches of the river, but a weak or even negative correlation in the middle and lower reaches of the river. This difference appeared to be caused by variation in hydrothermal conditions along the river as TWSA in areas with scarce precipitation in the middle and upper reaches of the river has a greater impact on vegetation. Apart from this, anthropogenic activities also played a role in their relationship. |
| Key words: vegetation index (NDVI); terrestrial water storage anomaly (TWSA); temporal and spatial changes; correlation analysis; Yellow River Basin |
