2000~2020年黄河流域植被时空演化驱动机制

以归一化植被指数（NDVI）作为植被覆盖及生长状况指标,基于2000～2020年MODIS NDVI数据及同时期气象数据,采用Theil-Sen斜率估算、Mann-Kendall检验、相关性分析和残差分析等方法研究了2000～2020黄河流域植被时空演化驱动机制.结果表明,2000～2020年黄河流域生长季NDVI均值以0.005 a^-1的速率波动上升,植被明显改善的区域主要分布于流域中游的秦岭山系、陕北高原和吕梁山系;黄河流域生长季NDVI与降水和气温的偏相关系数均值分别为0.57和0.49,降水对植被的影响高于气温;人类活动对植被生长起明显改善的区域主要分布在流域中部的陕北高原、吕梁山系和宁夏南部等区域,对植被生长起抑制作用的区域主要分布在银川、包头、西安、洛阳、郑州和太原等人类活动强烈的城市区域;人类活动和气候变化分别对黄河流域植被变化贡献了72%和28%,在人类活动和气候变化的驱动下,黄河流域植被生长得到改善的面积占流域面积的96.4%,其中人类活动贡献率大于80%的区域面积占34.3%,主要分布在流域中部和东南部.气候变化贡献率大于80%的区域面积占4....

Driving Mechanism of the Spatiotemporal Evolution of Vegetation in the Yellow River Basin from 2000 to 2020

The NDVI (normalized difference vegetation index) was used as the vegetation coverage index. Based on the NDVI and weather data from 2000 to 2020, the characteristics of the spatiotemporal evolution and the driving mechanism of vegetation were investigated by using correlation analysis, the Theil-Sen estimator, the Mann-Kendall method, and multivariate residual trend analysis. The results showed that the growing season average NDVI in the Yellow River basin was a fluctuating upward trend of 0.005 a^-1 from 2000 to 2020. Areas with significantly improved vegetation in the basin were mainly distributed in the Qinling Mountains, the Northern Shaanxi Plateau, and the Lvliang Mountains in the midstream. The average value of the partial correlation coefficient between the growing season average NDVI and rainfall in the Yellow River basin was 0.57, and the average value of the partial correlation coefficient between the growing season average NDVI and temperature was 0.49. The impact of rainfall on vegetation was higher than that of temperature. The areas where human activities significantly improved vegetation growth were mainly distributed in the northern Shaanxi Plateau, the Lvliang Mountains, and southern Ningxia. The areas where human activities inhibited vegetation growth were mainly distributed in cities with strong human activities such as Yinchuan, Baotou, Xi''an, Luoyang, Zhengzhou, and Taiyuan. Human activities and climate change contributed to 72% and 28% of the vegetation change in the Yellow River basin. Driven by human activities and climate change, the area where vegetation growth has improved in the Yellow River basin accounted for 96.4% of the basin area, of which the contribution rate of human activities greater than 80% of the area accounted for 34.3%, which was mainly distributed in the middle and southeast of the basin. The area with a contribution rate of climate change greater than 80% accounted for 4.2%, which was mainly distributed in the Sichuan-Tibet Plateau and Longzhong Loess Plateau in the basin. The results of this research can provide scientific support for the ecological protection and high-quality development of the Yellow River basin.