A Systems Approach for Analyzing Vegetative and Soil Degradation in Arnigad Micro-watershed of Indian Himalayan Region

This study analyzes the vegetative and soil degradation,measured as biomass and soil loss,for Arnigad micro-watershed located in Indian Himalayan state of Uttarakhand,in systems framework by using dynamic linear programming bio-economic model.The focus is at investigating the effects of alternate policy regimes,i.e.,introduction of improved energy sources for cooking along with substitution of existing local livestock breeds with improved breed,reduction in human population growth and introduction of high yielding varieties of main crops including paddy,maize and wheat.The model horizon extended over a period of 25 years,i.e.,from 2006 to 2030.It was found that the model scenario incorporating increased use of improved energy sources along with substitution of local cows by improved cows could be the most effective policy option in reducing vegetative and soil degradation.The vegetative biomass density declined to 19.76% compared to 35.24% in the BASE scenario and soil erosion loss was also lowered by 29.13%.Also,the reduction of population growth rate to half of the BASE scenario led to minor improvements in degradation.Introduction of high yielding varieties of main crops slightly increased vegetative degradation but reduced soil loss(8.35%) with respect to the BASE scenario.Such a phenomenon could be explained in terms of changed crop mix resulting in reduced amount of crop by-products requiring increased lopping of tree branches for animal fodder.The policy option of the increased use of improved energy sources along with substitution of improved breed of cows resulted in 9.58% higher income.Introduction of high yielding varieties of crops led to 1.92% increase in income,but the income decreased by 1.25 % when population growth was reduced to half.The usefulness of the model lies in analyzing the systems behavior in its entirety where the results can predict the possible direction of change as a result of manipulation in alternate economic regimes.