2000—2019年黄河流域植被覆盖度时空变化

科学认识黄河流域植被覆盖度的空间格局和时序变化特征,对了解黄河流域生态环境质量演变,综合治理水土流失具有重要的应用价值。本文基于MOD13Q1数据产品和国家气象站降水数据,采用像元二分模型、一元线性回归模型和Hurst指数,分析了2000—2019年黄河流域植被覆盖度空间格局、时序变化和发展趋势。研究发现：①黄河流域植被覆盖度年际变化呈明显的上升趋势,增长速度为0.0603/10 a,月际变化呈先升后降的变化过程,8月植被覆盖度达到最大值0.672;②流域中部植被覆盖明显改善,西北部和西部改善程度相对较低;③在空间上,呈现从西北至东南阶梯状增大的分布态势,河南省植被覆盖状况最佳;④降水量是影响植被覆盖空间分布的决定性因素,但对年际变化的影响较小,且对中游的影响程度明显大于上游地区;⑤未来黄河流域植被覆盖发展较好,植被覆盖度上升趋势占流域总面积的64.51%。研究可为黄河流域生态保护方案的制定提供数据支撑和科学指导。

Spatiotemporal change of fractional vegetation cover in the Yellow River Basin during 2000-2019

A scientific understanding of the spatiotemporal change of the fractional vegetation cover (FVC) in the Yellow River Basin (YRB) is of great significance for understanding the change of ecological environment quality and controlling soil erosion comprehensively. In this study, the MOD13Q1 data product and precipitation data from national meteorological stations during 2000-2019 were used to investigate the spatial pattern, temporal change, and future tendency of FVC in the YRB based on dimidiate pixel mode, simple linear regression model, and Hurst index. The results show that: (1) The FVC of the YRB shows an obvious rising tendency during 2000-2019, with a growth rate of 0.0603/10 a. Inter-monthly variation of the FVC presents a change process of increasing first and then decreasing, and the FVC reaches its peak (0.672) in August. (2) Spatially, the vegetational cover in the middle part of the YRB improved significantly during 2000-2019, while that in the northwest and west remained relatively low. (3) The FVC presents a step-like increase from northwest to southeast, and Henan Province has the best vegetation coverage among the nine provinces in the YRB. (4) Precipitation is a decisive factor in determining the spatial distribution of the FVC, but it has little influence on the inter-annual change of the FVC, and the influence degree on the middle reaches of the YRB is obviously greater than on the upper reaches. (5) Vegetational cover in the YRB will develop well, and the area with rising tendency of vegetation coverage accounts for 64.51% of the YRB. The research results provide some data support and scientific guidance for the formulation of ecological protection programs in the YRB.