基于MODIS-EVI的四川植被覆盖地形分布特征

Topographic Distribution Characteristics of FractionalVegetation Coverage Based on MODIS- EVI in Sichuan

借助Google Earth Engine平台,以MODIS-EVI数据为基础,运用GIS技术结合像元二分模型和分布指数定量分析四川省近20年来的植被覆盖地形分布特征.结果表明:①2000-2019年四川植被覆盖度以中覆盖度为主(64.56%),低覆盖度次之(17.04%),高覆盖度第三(13.59%),劣覆盖度第四(4.03%),无植被覆盖仅占0.78%;②无植被覆盖和劣覆盖度主要分布在高程>4500 m、坡度>15°、北坡、东北坡、西南坡和大起伏、极大起伏山地区域;③低覆盖度主要分布在高程3000~4500 m、西坡和西北坡区域;④中覆盖度主要分布在高程≤1000 m、坡度≤15°、台地、丘陵和小起伏山地区域;⑤高覆盖度主要分布在高程1000~3000 m、平地、东坡、东南坡、南坡和平原、中起伏山地区域.

Based on the MODIS-EVI,this article uses the Google Earth Engine remote sensing big data cloud computing platform analyzing the topographical distribution characteristics of fractional vegetation coverage in Sichuan in the past 20 years with the GIS and Dimidiate Pixel Model and Distribution Index.The results indicated that,from 2000 to 2019,the vegetation coverage was mainly medium coverage(64.56%),followed in the order of low coverage(17.04%),high coverage(13.59%),and poor coverage(4.03%),and free coverage only accounted for 0.78%.Free coverage and poor coverage were mainly distributed in the areas with elevations greater than 4500 m,slopes greater than 15°,north slopes,northeast slopes,southwest slopes,large and extremely undulating mountains.The low coverage was mainly distributed in the areas with elevations between 3000 m and 4500 m,west slopes and northwest slopes.The medium coverage was mainly distributed in the areas with elevations less than 1000 m,slopes less than 15°,terraces,hills and small undulating mountains.The high coverage was mainly distributed in the areas with elevations between 1000 m and 3000 m,flats,east slopes,southeast slopes,south slopes and plains,and medium undulating mountains.