Five decades of land use and land cover change in Bedadung watershed: Learning from Landsat data

Abstract

The Land Use and Land Cover (LULC) change can potentially propagate the hydrological alteration and cause severe hydro-meteorological disasters (such as landslide, flood or flash flood, or drought) that potentially occurred around the watershed areas. LULC change assessment in long time series is the primer step to evaluate and better manage the sustainability of natural resources. In this study, the Landsat images (dated from 1970 to 2020) were used as the primary input to calculate the LULC change in the Bedadung watershed. The Watershed (1002,85 km2) covers about 30% of the Jember regency area. The City of Jember is located in the middle of the Watershed. This study use Landsat 1 MSS, Landsat 5 TM, Landsat 7 ETM+, Landsat 8 OLI/TIRS captured from 1972 to 2020 as main input. The images data are processed using open-source image processing software. Furthermore, classification processes apply to produce LULC maps of 1972, 1997, 2002, 2017, and 2020. The LULC change is analysed by comparing the area extent occupied for eight LULC classes (i.e., built-up or pavement areas; paddy field; heterogeneous agricultural land; dense vegetation; sparse vegetation; barren land/sand/rock; shrubland; and water body. The results show that the change of pavement area slightly increased (by 3,63 % average) from 1972 to 1997 (25 years), and then increased significantly by 9,59% (average per year) from the period 1997 to 2020 (23 years). However, a very significant change was observed from 2017 to 2020, by 16,49% a year. The pavement area has increased significantly in the City of Jember during the last years and shows the rate of LULC change resulting from human-induced activities (i.e., residential use, industrial sites, road, and city infrastructures).