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One of the most serious environmental challenges facing the world today is land degradation, which is threatening many areas across the globe at an alarming rate (Devatha et al., 2015; Olorunfemi et al., 2020). Land degradation happens when natural and anthropogenic processes reduce the land’s capacity to sustain crops, livestock, and organisms (Bhan, 2013). Approximately 6 billion hectares of land have been impacted by various forms of land degradation worldwide, including soil erosion, sealing, pollution, salinization, and acidification (Mohammed et al., 2020; Wessels et al., 2007; Kertesz, 2009; Inbar & Zgaier, 2016; Ganasri & Ramesh, 2016, Djoukbala et al., 2018). Soil erosion is accelerated by uncontrolled deforestation, poor land use and land management practices, over-grazing, incorrect tillage, and unscientific agricultural practices adopted in the upland areas of watersheds (Arekhi et al., 2012). The most common effects of land degradation are a raised risk of flooding, eutrophication, turbidity, lowered topsoil nutrients, decreased agricultural output, decreased vegetation growth, excessive sedimentation, and other effects (Hlaing et al., 2008; Pradeep et al., 2015; Eniyew et al., 2021, Kebede et al., 2021).
Therefore, throughout the past three decades, watershed-level research has become the subject of both societal concern and hydrological exploration (Wang et al., 2016). Despite being a global problem, soil erosion is more prominent in the tropics and sub-tropics. In India, the sustainability of the human population is seriously threatened by soil erosion, which also jeopardizes the productivity of all other natural ecosystems, including wetlands, grazing, and agriculture. In addition, soil erosion induces aquatic imbalances, harm to drainage systems, declining water bodies and reservoir water quality, and environmental and infrastructural problems (Kumar & Sahu, 2020). The projected overall land degradation in India is estimated at 147 million hectares, of which around 94 million hectares have been degraded by acidity and the rest by flooding, wind erosion, salt, or a combination of these processes (Bhattacharyya et al., 2015).
The north-eastern region of India is endowed with distinct physical characteristics including mountainous topography and torrential downpours with broad spatial fluctuations. Thus, this region is vulnerable to significant soil erosion due to unsustainable and improper land-use practices along the steep hill slopes (Choudhury et al., 2022). To implement successful management techniques, it is necessary to conduct a quantitative and detailed assessment using a scientific database to determine the intensity and severity of soil erosion issues. This will further aid in identifying the probable sites for soil erosion. By implementing necessary strategies and measures, improved planning for soil conservation and agricultural activities could be accomplished (Tiwari et al., 2018). Soil loss estimation at the watershed level and its management through sub-watershed prioritization have been found to be authentic and satisfactory (Naqvi et al., 2012). Various empirical models have been developed to estimate soil loss, followed by watershed prioritization.