Land cover change mapping using a combination of sentinel 1 data and multispectral satellite imagery: a case study of Sanandaj county, Kurdistan, Iran

Abstract

Land Cover Maps (LCMs) represent the integrated information about general status of a specific region, which are widely used as a baseline for many related purposes. This study aims to extract the land covers of Sanandaj County, Kurdistan, Iran, along with to highlight the occurred changes compared with an old map prepared by the Iranian Institute of Water and Soil in 2010. The combination model of Sentinel-1 and Landsat-8 satellite imageries was used for the dates 10/05/2017 and 11/05/2017, respectively. It is noted that based on the location of the study area we acquired Sentinel-1 data and a pair of Landsat-8 images. Using Sentinel Application Platform (SNAP) and Environment for Visualizing Image (ENVI) softwares all images were corrected, co-registered and stacked. The combination of RADAR, NDVI and thermal bands was utilized as the best combination for the visual interpretation, with which all land covers can be easily differentiated. However, with help of the Google Earth images the land covers (polygon by polygon) were checked and digitized. Results indicate that the visual interpretation of the combination model with the assist of Google Earth is a robust way to extract land covers, provided that the researchers have enough knowledge on the land covers of the study area. This study can be applicable for decision makers of Sanandaj City.