河北坝上地区2000-2019年植被绿度动态及其土地利用/覆被变化归因分析

目的] 分析河北坝上地区植被绿度变化及土地利用/覆被变化，旨在为区域生态建设和京津冀生态环境支撑区的建设提供科学参考，为土地合理利用及生态环境保护提供决策支持。方法] 以MODIS MOD13Q1 NDVI遥感数据为数据源，结合Landsat土地利用数据，使用线性倾向估计分析了2000—2019年坝上地区植被绿度的年际变化趋势，并定量分析了土地利用/覆被变化对其的影响。结果] ①河北坝上地区主要生长季（4—10月）多年平均植被绿度整体上呈现坝东高，坝西低的空间格局，且林地>草地>耕地； ②研究时段坝上地区生长季NDVI最大值和平均值均呈现明显的增加趋势，速率分别为0.063/10 a和0.044/10 a，植被绿度显著提升区域比例为60%～83%； ③结合土地利用变化定量解析植被绿度年际变化发现，研究时段，坝上地区植被绿度变化量中，耕地的贡献率为50.51%～57.22%，其次，林地和草地的贡献率分别为21.73%～28.62%和14.41%～15.07%，水域、建设用地和未利用地的总贡献率在6%左右。结论] 2000—2019年，坝上地区植被绿度增加趋势中耕地的贡献最大，但贡献率呈下降趋势，林地和草地的贡献逐渐增加。

Vegetation Greenness Change and Its Attribution Related to Land Use and Land Cover Change in Bashang Area of Hebei Province During 2000-2019

Objective] The vegetation greenness dynamics and attributions of land use/cover change in Bashang Plateau were analyzed, in order to provide scientific reference for the construction of local ecology and the environment support area for Beijing-Tianjin-Hebei region, and to support decision-making for land use planning and ecological environment protection.Methods] MODIS MOD13Q1 NDVI dataset and Landsat-derived land use data in Bashang area were used to analyze the change trend of vegetation greenness during 2000-2019 and its attribution by linear tendency estimation and partial derivative attribution method.Results] The average vegetation greenness during the main growing season (April to October) was generally high in the east, while low in the west of the plateau. Moreover, the average vegetation greenness was the highest on the woodland, while the lowest on the cultivated land. During 2000-2019, the maximum and the average NDVI in Bashang area showed an obvious increasing trend, with the rates of 0.063/10 a and 0.044/10 a, respectively, and areas with significant improvement of vegetation greenness accounted for 60%~83%. According to the quantitative analysis of the interannual land use and land cover changes in Bashang Plateau, the contribution rate of cultivated land, woodland and grassland was 50.51%~57.22%, 21.73%~28.62% and 14.41%~15.07%, respectively, during 2000-2019. The total contribution rate of water area, construction land and unused land was only 6%.Conclusion] During 2000-2019, cultivated land contributed the most to vegetation greenness increase in Bashang area of Hebei Province, but the contribution rate shows a downward trend, and the contribution rates of woodland and grassland increases gradually.