Role of Sacred Groves in Tree Diversity Conservation in Kathmandu Valley, Nepal

Abstract

Study about the role of Sacred Groves in tree diversity, both native and planted species, conservation was conducted in Pashupati and Bajrabarahi Sacred Groves of Kathmandu valley, in the central middle hill physiographic region of Nepal. Study sites contain centuries old sacred groves preserved due to strong religious and sociocultural practices and belief systems. The study was conducted to analyze the community structure and carbon stock in tree canopy and to assess regeneration status and threats to determine the conservation and values of sacred groves. Concentric Circular Plots with radius of 20 m prepared along eight and four parallel transects in Pashupati and Bajrabarahi Sacred Groves were used to get information on tree and soil characteristics and forest disturbances. Structured questionnaires were used to collect local perceptions about the role of Sacred Grove in biodiversity conservation. From the phyto-sociological assessment three types of forest in Pashupati Sacred Grove and only one forest type was identified from Bajrabarahi Sacred Grove. In Pashupati Sacred Grove, 13 plant families with 17 mature tree species were recorded and 12 families with 18 mature tree species were identified from Bajrabarahi Sacred Grove. Both groves shared nine common families and ten common tree species with similarity indices 72% for families and 57% for tree species. Bajrabarahi Sacred Grove incorporated more developed forest community with mature trees and less number of stems (432 ha -1 ) and higher crown cover percent (90.8%) than that of Pashupati Sacred Grove. Tree species of Pashupati Sacred Grove were more diverse (diversity index = 1.91) and more evenly distributed (evenness = 0.67) than Bajrabarahi Sacred Grove. Trees of both study sites contains 1014.23 tons of average Carbon stock and CO2 3.7 mt. The highest amount of Carbon stock (622.09 t) and CO2 (2.28 mt) was reported in the trees of Quercus-Myrsine forest and the lowest Carbon stock (113.98 t) and CO2 (0.42 mt) in the trees of Schima-Pyrus forest of Pashupati Sacred Grove. The regeneration status of tree species in Pashupati was good and that found fair in Bajrabarahi Sacred Grove. Based on Disturbance Index the disturbance statuses of study area were identified as undisturbed, least disturbed, moderately disturbed and highly disturbed. The soil was found acidic in both groves; nitrogen content was low in Pashupati and medium in Bajrabarahi. The organic matter content was in medium range and potassium and phosphorus content were found very high in the soil of both groves. Local people perceived the objective to establish sacred grove was for biodiversity conservation. The forest was found more protected in Bajrabarahi and less conserved in Pashupati. Local perception towards the conservation of sacred groves was optimistic and stakeholders realizing the positive role of local faiths and belief system toward conservation. As a pioneer concept of the participatory biodiversity conservation model, government needs to provide priority for the sacred grove conservation.