Scientific forest management is an emerging need for managing existing natural forests of Nepal on the basis of silvicultural intervention. The study was carried out in Lumbini Collaborative Forest at Rupandehi District of Nepal, where Sal (Shorea robusta) forests are being managed under Irregular Shelterwood System with eighty years of cutting cycle since 2011-2012. The study was purposed to find out the intial effects of silvicultural intervention on plant species diversity and regeneration of Sal forest. The vegetative sampling was done using quadrate method based on the principle of simple random sampling both in the managed as well as the unmanaged parts of forest. The study found out remarkable increase in regeneration as well as decrease in plant diversity in the managed first and second-year stands (Block I and Block II respectively) as compared to the unmanaged stand (Block III) at its initial level of implementation. The mean value of diversity, richness, evenness, dominance index and regeneration of S. robusta varied significantly (p≤0.05) between the managed blocks (stands). The seedling density of S. robusta was found higher in the managed blocks (Block I and Block II) as compared to the unmanaged one (Block III) in terms of height class. The study recommends implementation of Irregular Shelterwood System for managing the existing degraded Sal forests of the Terai region of Nepal, however, its long term effects on plant species diversity should be further studied in detail.

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Soil erosion is a major concern for the environment and natural resources leading to a serious threat to agricultural productivity and one of the major causes of land degradation in the mid-hills region of Nepal. An accurate assessment of soil erosion is needed to reduce the problem of soil loss in highly fragile mountainous areas. The present study aimed to assess spatial soil loss rate and identified risk areas and their perceived impact on agricultural productivity by using the Revised Morgan–Morgan–Finney (RMMF) model and social survey in the Rangun watershed of Dadeldhura district, Nepal. Soil erosion was assessed by using data on soil, digital elevation model, rainfall, land use, and land cover visually interpreted from multitemporal satellite images, and ILWIS 3.3 academic software was used to perform the model. A household questionnaire survey (n = 120) and focus group discussion (n = 2) in identified risk areas were carried out to understand the people’s perception towards soil erosion and its impact on agricultural productivity. The predicted average soil erosions from the forest, agriculture, and barren land were 2.7 t ha−1 yr−1, 53.73 t ha−1 yr−1, and 462.59 t ha−1 yr−1, respectively. The erosion risk area under very low to low, moderate to moderately high, and high to very high covers 92.32%, 4.96%, and 2.73%, respectively. It indicates that the rate of soil erosion was lower in forest areas, whereas it was higher in the barren land. The cropped area of the watershed has been reduced by 2.96 ha−1 yr−1, and productivity has been decreased by 0.238 t ha−1 yr−1. The impacts such as removal of topsoil (weighted mean = 4.19) and gully formation (weighted mean = 3.56) were the highest perceived factors causing productivity decline due to erosion. People perceived the impact of erosion in agricultural productivity differently ( ∗ significant at P ≤ 0.05 ). The study concluded that, comparatively, barren and agricultural lands seem more susceptible to erosion, so the long-term conservation and management investment in susceptible areas for restoration, protection, and socioeconomic support contribute significantly to land rehabilitation in the Rangun watershed.

Scientific forest management (SciFM) ensures improved productivity and healthy forests that are crucial for the economic development and prosperity of forest-dependent country like Nepal. This study analyzes the effects of the silvicultural intervention on the regeneration of Sal (Shorea robusta), plant species diversity, and income through the flow of forest products in the Patela Community Forest in Kailali District of Nepal, where Sal (S. robusta) forest has been managed under an Irregular Shelterwood System with 80 years of the rotation period since fiscal year 2017/18. The vegetation sampling was done by the quadrat method based on the principle of stratified random sampling from the managed and unmanaged parts of the forest. The climate based site productivity was analyzed. The profitability of scientific forest management was analyzed by income and cost incurred in managing the forest. The study revealed the promising regeneration of S. robusta in the managed areas compared to the unmanaged area. The silvicultural intervention had a significant negative effect on plant diversity showing an increase in the concentration of dominance of S. robusta. An implementation of SciFM plan generated a total net benefit of 187,000 US$ in the last 2017/18, and 2018/19 fiscal years. This study recommends existing natural forests to be managed based on sound silvicultural principles to improve the degrading nature of the productive forest that can generate revenue for the country and opportunity for community development.