ABSTRACT Food security and the sustainability of ecosystems are seriously threatened by land degradation, especially in the Indo‐Gangetic Plains where soil erosion, salinization, and waterlogging are the main causes. This study integrated these three forms into a unified, versatile, and globally adaptable Land Degradation Index (LDI) for comprehensive land degradation assessment, using Sultanpur district, Uttar Pradesh, India as a case study. Soil erosion susceptibility was initially assessed using the Revised Universal Soil Loss Equation, whilst salinization and waterlogging were independently evaluated with a Frequency Ratio using 25 and 21 factors, respectively. The resulting susceptibility maps demonstrated high predictive accuracies, with Area Under the Curve (AUC) values of 97.3%, 94.5%, and 90.1%, respectively. LDI was subsequently calculated using these maps as inputs to integrate the three degradation processes into a unified index representing overall land degradation intensity. It identified and mapped the most severely affected areas, revealing that approximately 20% of the agricultural land in the study area was impacted by land degradation. This study also developed novel random forest regression models integrated with SHapley Additive exPlanations (SHAP)‐based Game theory to examine the behaviour of conditioning factors in high and low susceptibility zones of Sultanpur district. The models fitted with MSE 0.86. Soil salinization was found to be the primary driver of soil fertility loss in this study. This salinization is primarily driven by vegetation loss, changes in soil pH, overuse of nitrogen‐rich fertilisers, and proximity to canals. Identifying the key drivers of land degradation and understanding their localised impacts provides vital insights for promoting sustainable agriculture and guiding evidence‐based policymaking. These findings further highlight the broader global relevance of adopting site‐specific land management strategies, particularly through vegetation restoration, balanced fertiliser use, and efficient irrigation, to sustain the productivity and resilience of agro‐ecosystems like Sultanpur district.
Kumar et al. (Sat,) studied this question.