Environmental hazards of land use/land cover dynamics using data observation techniques and GIS: case study of Guyuan watershed, China

Abstract

Abstract Agricultural production system is extensively impacted by dynamics of land use. In the present paper, dynamics of land use and land cover (LULC) and environmental factors such as digital elevation model (DEM), slope, vegetation cover, soil type, and aspect were assessed to simulate the potential hazard in the watershed area at the southern part of Ningxia, Guyuan. This area was selected due to its wealthy fertile soils; thus, it provides food for multiple regions. Guyuan, Shilitan, and Yangcao cities were chosen as case studies. Multispectral Gaofen (GF) 2 satellite images and SRTM DEM were processed to produce environmental variables to assess the probable risks. In Shilitan watershed, very dense vegetation showed an increase from 14.6 to 22.1% and in Yangcao from 5.65 to 9.46% at 2005 and 2019, respectively, which protects the watershed area from flood and land degradation. However, spare vegetation recorded a decrease during the investigated period in two watershed areas. Hence, soil with little vegetative cover is more vulnerable to erosion, degradation runoff, and inconsequential water retention. DEM analyses showed that higher degree of segmentation leads to more degradation and damage of agricultural lands which adversely affects food security of the city. Results of the present study help policy makers, planners, and other accompanying development workers to apply the best suitable land use management options to protect Guyuan watershed.