Indicator-based vulnerability assessment of forest ecosystem in the Indian Western Himalayas: An analytical hierarchy process integrated approach

Abstract Understanding the vulnerability of forests and its associated factors is crucial for the sustainable management of forested landscapes. The assessment of vulnerability of forests in the Indian Western Himalayan (IWH) region comprising the states of Jammu & Kashmir (J&K), Himachal Pradesh (HP) and Uttarakhand (UK) was done using six indicators of vulnerability in the form of biological richness index, disturbance index, forest canopy density, fire point intensity and forest extraction intensity of fringe forests. We express this assessment as the “indicator-based vulnerability”. The indicators were allocated weights by multi criteria analysis using analytical hierarchy process. The spatial extent of all of the selected indicators was mapped for the IWH region at a pixel resolution of 24 m and was integrated to find out the vulnerability for each pixel in a GIS environment. The study area was divided into 172 grids of size 0.5°, equivalent to the grid size of available climatic projections, out of which 67 grids were identified as the forest grids. The grids that have at least 5% forest cover were designated as the forest grids and the vulnerability assessment was done only for these grids. The final representation of vulnerability across forested grids of the IWH was done at a spatial resolution of 5' and 0.5° to categorise as low, medium, high and very high class. It was observed that the highest concentration of “very high” and “high” vulnerable grids of 5' size lies in the state of UK, comprising 32 and 31%, respectively. The aggregated values at 0.5° indicate that most of the grids of UK fall under very high vulnerability except for the few uppermost and lowermost grids falling under other categories. In J&K, most of the 5' grids fall under low vulnerability (41%), while medium, high and very high categories are 27, 25 and 7%, respectively. Similarly, out of total 28 grids of size 0.5°, only one grid is categorized as very high vulnerable, while 11 grids fall under high vulnerability. In HP, none of the grids of either size is categorized as very high vulnerable. It was observed that most of the high and very high vulnerable grids in the IWH are in the lower altitudes while higher altitudes have lesser magnitude of vulnerability. Forests occurring at a higher elevation such as the Alpine forests (dry, moist and sub-alpine) is the least vulnerable forests compared to other forest type groups of the IWH.