Assessing the Environmental vulnerability and its impacts on livelihood in Dudhkoshi Basin in Eastern Nepal

Keywords: Nature Based Solutions, Climate Change Adaptation, Disaster Risk Reduction, rural livelihood  , Nepal Himalayas

Abstract:

Climate has been changing and has considerable impacts on the livelihood of rural/urban communities all around the globe. The impacts however are more pronounced in the mountainous region such as in the Dudhkosi Basin (~4,063km²) in eastern Nepal. Studies suggested that the mountainous region of Nepal are climate-sensitive meaning that a small change in air temperature could bring significant impacts on the environmental degradation process and increase the frequency of climate-induced hazards and risk of disasters. In order to understand the dynamics of the changing climate on rural livelihood, this research attempted to model the environmental vulnerability of the basin considering the topographic and environmental attributes and assessed their contribution to the physical environmental degradation process. Multi-criteria based Decision Analysis (MCDA) approaches were implemented considering the seven primary topographic attributes such as slope, soil type, land use, NDVI, elevation, distance to drainage, and terrain wetness. The model was implemented for the three scenarios of rainfall such as historical and projected precipitation for RCP4.5 and RCP 8.5 as a climate change variable and distance to the rural roads as an anthropogenic factor to model the physical environmental degradation there by the vulnerability. The analysis depicted that the slope attributes has the highest contribution (20.21%) among all followed by precipitation, soil type, land use, distance to road, distance to drainage, terrain wetness and NDVI respectively 18.5%, 14.3%, 12.56%, 10.75%, 9.63%, 7.55% and 6.5%. The analysis clearly indicated that the slope is one of the most critical attributes where many settlements are located and have a significant contribution to the land-degradation process of the mountainous region. While the increasing trend of rainfall will cause more soil erosion and shallow landslides compounded due to the unplanned construction of rural roads thereby more area of the basin under the threat of degradation. The model also indicated that the increased amount of degraded land for the projected precipitation scenarios under RCP4.5 and RCP8.5 respectively increased from 7% to 15%. The increased amount of degradation will cause more communities living on the sloping terrain will turn to be vulnerable. The analysis demonstrated in this research suggested that the basin is at high threat of land degradation under the climate change scenarios for which an integrated basin management plan is to be developed. Integrated approach for Building Climate Resilience is the key in which the Nature-Based Solutions measures as climate change adaptation and disaster risk reduction. The measures also  improve the watershed conditions that subsequently enhance the quality of the lives of the people with increased economic opportunities and coping capacity for the climate change induced disasters and community resiliency.