Temporal-spatial Analysis Of Vegetation Coverage Dynamics In Beijing-Tianjin-Hebei Regions

As the core and functional part of the geographical environment,vegetation constitutes the most perfect land ecosystem and the largest biomass production.The dynamic evolution of vegetation cover is not only an important indicator of regional ecological environment change,but also a basis for evaluating the ecological environment.Taking the construction of the ecological system of Beijing-Tianj in-Hebei metropolitan regions as the background,based on MODIS NDVI remote sensing data from 2005 to 2015,combined with DEM,statistical yearbook,land cover type and Chinese ecological zoning and other data,using the maximum synthesis method,average method,a linear regression model,pixel dichotomy and differential analysis method,the stability analysis,continuous analysis and other related statistical basic knowledge,studied the vegetation coverage of the remote sensing estimation method to monitor the dynamic changes in vegetation coverage and trends,and to assess its stability,sustainability and future evolution risk for forming an ecological integrity network,and build a regional ecological security pattern to provide a scientific basis.The results show that:The NDVI mean of vegetation in Beijing-Tianjin-Hebei region shows an upward trend,and there are obvious differences in time and space;The vegetation coverage showed obvious seasonal differences,and there were significant distributions at different altitudes;During the study period,the vegetation evolution was mainly improved and showed strong persistence;The overall performance of the "high and low volatility coexist,low volatility,regional obvious";The characteristics of vegetation evolution in different ecological zones are obvious,The vegetation coverage of population-leading cities is higher in different time periods,but the potential degraded areas account for a higher proportion.