A recent study has shed light on concerning trends regarding soil erosion in India, indicating significant threats to the nation's soil health. Conducted as the first comprehensive attempt to classify soil erosion on a pan-India basis, the research paints a picture of widespread degradation. The study, titled "Geospatial Modelling and Mapping of Soil Erosion in India," published in Science Direct, categorizes soil erosion into six classifications, ranging from "minor" to "catastrophic," based on the extent of soil loss per hectare over a year.
Soil erosion, the process by which soil is displaced or removed from its original location, is a natural geological phenomenon aggravated by various factors including deforestation, overgrazing, improper agricultural practices, urbanization, and climate change. These activities accelerate the loss of the topmost fertile layer of soil, significantly impacting agricultural productivity, upon which a significant portion of the Indian economy relies.
Despite the critical importance of understanding soil erosion's impact, a national-scale assessment and impact classification system has been lacking in India. Given the logistical challenges of conducting field experiments across such a vast and diverse landscape, the study utilized the Revised Universal Soil Loss Equation (RUSLE) for soil erosion calculations. This method provided a streamlined approach with accurate results, essential for assessing soil loss across the nation.
Key Findings
The study estimates that nearly 30% of India's landmass is experiencing "minor" soil erosion, while a critical 3% faces "catastrophic" topsoil loss. Rainfall erosivity emerged as a significant factor influencing soil erosion, with rainfall intensity and topographic features playing crucial roles. Sediment Delivery Ratio (SDR) and Specific Sediment Yield (SSY) were mapped to assess actual soil loss reaching downstream basins, with national mean values calculated at 0.11 and 2.61 tons per hectare per year, respectively.
Notably, nine out of the twenty districts most susceptible to soil erosion are located in the state of Assam. This underscores the urgent need for targeted conservation efforts in these regions to mitigate further soil degradation.
The absence of comprehensive national-scale estimates prompted the study to fill this crucial knowledge gap. By utilizing advanced geostatistical models and incorporating diverse parameters such as rainfall intensity, soil properties, land use, and agricultural practices, the research provides a detailed understanding of soil erosion dynamics across India.
The findings of this study offer valuable insights for policymakers, land owners, and conservationists. By implementing the newly introduced erosion-severity classification system, stakeholders can prioritize and tailor soil conservation strategies at both local and national levels.
With comprehensive data-driven insights and a soil classification system, the study lays the groundwork for effective soil conservation efforts essential for sustaining India's agricultural productivity and environmental resilience in the face of ongoing challenges.
