Geospatial assessment of land use/land cover changes from feldspar exploitation in Zango-Daji, Nigeria

Abstract

This study investigates the extent to which feldspar mining has altered land use/land cover (LULC) changes in Zango Daji, a topic underexplored in existing literature. These changes are linked to reduced agricultural productivity and increased conflicts over land rights. The Landsat imageries were used to assess the LULC changes as a result of artisanal mining of feldspar in the study area from 2002 to 2022. Online imageries obtained from archive of Global Land Cover Facility (GLCF) under the United States Geological Survey (USGS) were analyzed using Enhanced Thematic Mapper Plus (ETM+) of 2002, 2007 and 2012, and the Operational Land Imager (OLI) of 2017 and 2022. ArcMap 10.8 was used for the pre-processing and clipping of the area of interest, using both the administrative and local government maps. It was later used for visualization, calculation, processing and analysis of all the digital imageries. Four geospatial index maps of normalized difference vegetation index (NDVI), modified normalized difference water index (MNDWI), normalized difference built-up index (NDBI), and dry bare soil index (DBSI) were generated between 2002 and 2022 at an interval of five years. The accuracy was enhanced using Google Earth imagery for validation. The results revealed that vegetation improved marginally after mining began, compared to the pre-mining era. Meanwhile, a year (2012) after artisanal mining began in 2011, water witnessed its peak stress. Dry bare soil and built-up have increased considerably since feldspar mining began in the area. The findings inform sustainable land management and conflict mitigation strategies in mining regions.