山地新城土地利用/植被覆盖的时空演变规律——以重庆渝北区为例

为探求山地新开发区城市化进程中的土地利用/植被覆盖时空演变规律，以重庆市渝北区为研究对象，利用遥感手段对渝北区1995—2020年历史影像进行解译，结合土地利用转移矩阵，城市空间扩张分异变化分析了渝北区6期的土地利用(land use and climate change, LUCC)时空演变特征；利用高光谱遥感影像分析归一化植被指数(normalized digital vegetation index, NDVI)的时空演变规律，定量评估了LUCC变化对NDVI的影响。结果表明：1995—2020年间渝北区城市建设用地不断扩张以占用农田为主；城市重心略向西南部移动，建设用地偏离紧凑，形状扩张往复杂化发展。渝北区NDVI在1995—2020年间以1%/a的趋势下降，所有土地类型的NDVI均减小；空间上整体呈先增大再减小趋势，2010年后西南部和中东部区域减小明显；夏季NDVI波动最大，冬季最小，夏季植被覆盖主要受气温的影响，秋季主要受降水的影响；四季的NDVI在空间均呈中部向南、北部递增的趋势，与城市空间扩张规律类似。气候波动对渝北区植被覆盖总变化的贡献率为14.22%,其中温度是气...

Spatiotemporal evolution of Land Use/Vegetation Cover in new mountainous cities: A case study of Yubei, Chongqing

In order to explore the spatiotemporal evolution of land use/vegetation cover in the process of urbanization in mountainous new development area, taken Yubei district of Chongqing as the research area, the historical images of Yubei district from 1995 to 2020 were interpreted by remote sensing, based on the land use transfer matrix, the spatial and temporal evolution characteristics of LUCC in the 6 period of Yubei District were analyzed. The spatial and temporal evolution of normalized vegetation index (NDVI) was analyzed by using binary pixel model to calculate vegetation coverage, and the impact of LUCC change on vegetation coverage was quantitatively evaluated. The results show that from 1995 to 2020, the urban construction land in Yubei District was mainly occupied by farmland. The center of gravity of the city moves to the southwest slightly, the construction land deviated from compact, and the shape expanded to complicate development. The NDVI of yubei District decreased by 1%/a from 1995 to 2020, and the NDVI of all land types decreased. The overall spatial trend increased first and then decreased, and decreased significantly in the southwest and central eastern regions after 2010. The fluctuation of NDVI was the largest in summer and the smallest in winter. The vegetation coverage was mainly affected by temperature in summer and precipitation in autumn. NDVI in four seasons showed an increasing trend from central to south and north regions, which was similar to urban spatial expansion. The contribution rate of climate fluctuation to the total change of vegetation cover in Yubei district was 14.22%, and temperature was the main factor affecting NDVI. The contribution rate of land use change to vegetation cover change in the study area was 85.78%, and its influence gradually increased. Farmland contributed the most to vegetation cover change in each period, the expansion of construction land''s contribution to the vegetation coverage rate increased.