Estimation of Spatial and Temporal Changes in the Net Primary Productivity of an Open Cast Mine in Dongri Buzurg, Maharashtra Utilizing Satellite-based CASA Model

Abstract

ABSTRACT Open cast mining activities contributes to rapid change in vegetation dynamics and severe damage to ecological environment. Landuse and landcover (LULC) change in the opencast mining area can have significant impact on regional ecosystems and carbon cycle. In this study, LULC change dynamics is studied over an opencast Dongri Buzurg manganese mine in Maharashtra for the period 2014 to 2022. The area has experienced significant changes in LULC, making it critical to evaluate the environmental effect and suggest strategies for lowering its impact on net primary production (NPP). NPP was measured using remote sensing data from two satellite platforms (Sentinel 2A and MODIS) for the period 2014 to 2022. Simulated model such as the climate productivity model (Thornthwaite Memorial) was used to correlate satellite-derived NPP data. The spatial and temporal changes in NPP with respect to LULC were analyzed. Out of the total 78 km2 of area, 8.33 km2 of land has been converted which resulted in net reduction of NPP from 5.71 gC/m2/day (2014) to 4.45 gC/m2/day (2022) (H” 3.34 gG of net carbon lost into the atmosphere over a span of 8 years). The transformation of forest area to degraded land was the most significant contributor to NPP decline, accounting for 40.55% of overall NPP reduction. Based on the measured NPP results, a correlation analysis was performed with simulated NPP derived from the climate productivity model to understand the effectiveness of remote sensing data in NPP retrieval. Both S2A and MODIS data showed good agreement with that of the climate productivity model (R2 = 0.580 and 0.689 for MODIS derived NPP for the year 2014; R2 = 0.655 for Sentinel 2A derived NPP for the year 2022). These findings may serve as a guide for scientific evaluation of ecological losses due to mining and search for more effective and sustainable land reclamation techniques. Present study also demonstrates the application of finer resolution satellite data Sentinel 2A and MODIS for estimation of NPP. The findings might serve as a guide for further research into how mining affects local surroundings and for the investigation of more effective methods for land reclamation.