Soil erosion and nutrients loss are serious problems on the hillslopes of North Western Himalayan Region. Huge loss and alteration in physico-chemical properties of top soil gradually reduces its productivity. In this study, an experiment was executed in Mollisols with 12% slope for two successive years under natural monsoon season with the objective to minimize soil loss and improve soil properties involving three soil amendments namely gypsum (G), biochar (B) and polyacrylamide (PAM). Incremental effect of B, PAM and G, were used at pre-determined dose of 800 and 1500 g/m², 2 and 4 g/m², and 250 and 500 g/m${}^2$ in first and second trial, respectively. Treatment effects were evaluated on runoff, soil erosion, biochar loss, major nutrient loss (N, P and K), soil pH, EC, hydraulic conductivity, bulk density, liquid and plastic limits, and biomass. Application of B+PAM reduced surface runoff by 24.44 and 43.13% and sediment yield by 42.43 and 84.61% in first trial and second trial, respectively. It also showed significant improvement in soil physico-chemical properties and biomass growth in comparison to other treatments. Similarly, nutrient loss was also found to reduce in the same proportion as runoff and soil loss. Support vector regression with linear function showed very reliable results in predicting biochar and major nutrient losses with Nash-Sutcliff efficiency (NSE) more than 0.92 and 0.84, respectively, and correlation coefficient (CC) more than 0.98 and 0.93, respectively, during testing period.

土壤侵蚀和养分流失是喜马拉雅西北部地区山坡上的严重问题。表层土壤物理化学性质的巨大损失和改变逐渐降低了其生产力。在这项研究中，在自然季风季节下连续两年在坡度为 12% 的 Mollisol 中进行了一项实验，目的是最大限度地减少土壤流失并改善土壤性质，涉及三种土壤改良剂，即石膏 (G)、生物炭 (B) 和聚丙烯酰胺 ( PAM）。B、PAM 和 G 的增量效应，以 800 和 1500 g/m ²、2 和 4 g/m ²以及 250 和 500 g/m ^{2 的}预定剂量使用${}^2$分别在一审和二审中。对径流、土壤侵蚀、生物炭损失、主要养分损失（N、P 和 K）、土壤 pH 值、EC、水力传导率、体积密度、液体和塑性极限以及生物量的处理效果进行了评估。一审和二审中，B+PAM 的应用分别减少了 24.44% 和 43.13% 的地表径流和 42.43% 和 84.61% 的产沙量。与其他处理相比，它还显示出土壤理化特性和生物量增长的显着改善。同样，还发现养分损失与径流和土壤损失的减少比例相同。具有线性函数的支持向量回归在预测生物炭和主要养分损失方面显示出非常可靠的结果，纳什-萨特克利夫效率 (NSE) 分别超过 0.92 和 0.84，相关系数 (CC) 超过 0。