Effects of Anthropogenic Disturbance on Diversity, Biomass and Storage of N and P Nutrients by Herbaceous Vegetation of Gall Oak Stands (Case Study: Shine Qellaii Forests, Lorestan Province)

This study investigates the role of man-made disturbance on on nitrogen and phosphorus nutrient storage by herbaceous species in Gall Oak stands of Lorestan province. In order to do this study, two sites with the same physiographic and ecological conditions and different land uses were selected. Multiscale sampling plots were used randomly in each site to collect data on forest floor vegetation, trees and soils. Richness and biodiversity indices, generalist species, herbaceous biomass, nitrogen and phosphorus content of the plant tissues and nutrient storage were compared in two sites. Results showed significant differences in the two studied sites, between species richness, the number of herbaceous species, Margalaf richness and Shannon-Weiner diversity indices, above-ground and below-ground biomass. Also the above-ground and below-ground biomass were greater 43.7% and 35.3% respectively in the protected forest. Based on the results more amounts of nitrogen and phosphorus was stored by herbaceous species in protected forest. Also more native species and surface soil fertility improvement in the protected site revealed that conservation programs led to better environmental conditions and provide suitable conditions for ecosystem resilience. Also, more amounts of nutrients stored by herbaceous species in protected forest indicates that these plants plays important role in the storage of nutrients in the ecosystem. As the amounts of nutrients was less in the disturbed forest.