MBaI: A Modified Barren Index for Classification of Barren Land in Coal Mining Regions of Eastern India

Mine reclamation is a process in which a mine pit is back-filled with overburden, covered with topsoil, and revegetated. It is essential to monitor barren areas that require revegetation for long-term reclamation monitoring. The study introduces a Modified Barren Index (MBaI) to classify barren areas in a coal mining region. The MbaI is a computationally efficient and effective approach for differentiating barren areas from active mines, overburden dumps, built-up areas and vegetation to support mine reclamation and monitoring. The new proposed index utilizes near- and shortwave infrared to distinguish between bare soil and other surfaces. Using Landsat 8 and Sentinel 2, the study was carried out in the Jharia Coal Field region in India and compared with commonly used indices, i.e., the Biophysical Composition Index, Modified Bare Soil Index and Normalized Difference Bare Soil Index. The comparison between actual reflectance data and laboratory ECOSTRESS data attests that MbaI can effectively differentiate between barren and non-barren areas while other indices struggled. The index was tested in coastal, snow and desert regions for assessing efficiency, with accuracies of 98%, 97% and 91% using Landsat 8 and 94%, 94% and 96% using Sentinel 2 data, respectively. The extracted barren areas using MbaI exhibited lower NDVI and NDMI values compared to areas extracted from other indices, suggesting better efficiency. The study can be useful for achieving faster and accurate classification of barren areas from non-barren areas in mining and non-mining regions in the Indian subcontinent using multi-satellite data. However, wet soil can limit the accuracy of barren area extraction by MbaI, which can become a major limitation with coal mining regions experiencing regular rainfall.