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Land use has a greater impact on trace element (TE) concentration present in soils. In mountainous regions of the western Himalayas, some dominating geogenic and human-dependent anthropogenic factors are involved in the spatial distribution of TEs in various land uses. Soil samples were collected from permafrost, pasture, forest, and agricultural land-use systems of Babusar Valley and Fairy Meadows in Diamer districts and the Rama region in Astore Districts in replications for investigation of three TEs, i.e., copper (Cu), zinc (Zn), and nickel (Ni). These samples were analyzed for exchangeable, adsorbed, organically bound, carbonate precipitated, and residual forms. Significant differences among these TEs were observed. Differences in the levels of TEs within soil samples were observed to be influenced by land usage patterns. The physicochemical properties of soil samples were also investigated. Additionally, the total metals (Ni, Zn, Cu) were extracted and their concentrations were measured in all samples. The concentration of soil TEs was observed in the following order: adsorbed < organically bound < exchangeable < residual < carbonate precipitated form across all the land uses. The results indicate that the contents of TEs (Ni, Zn, Cu) in agricultural soils were greater than in the permafrost pasture and forest soil samples. The total TE concentration varied as Zn > Ni > Cu irrespective of the area and land uses. We believe this work will open avenues for researchers to explore TEs in various regions of the world. [ABSTRACT FROM AUTHOR]

Vegetation structures and dynamics are the result of interactions between abiotic and biotic factors in an ecosystem. The present study was designed to investigate vegetation structure and species diversity along various environmental variables in the Yakhtangay Hills of the Hindu-Himalayan Mountain Pakistan, by using multivariate statistical analysis. Quadrat quantitative method was used for the sampling of vegetation. PC-ORD version 5 software was used to classify the vegetation into different plants communities using cluster analysis. The results of regression analysis among various edaphic variables shows that soil organic matter, total dissolved solids, electrical conductivity, CaCO3 and moisture contents shows a significant positive correlation with species abundance, while the soil pH has inverse relationship with plant species abundance. Similarly, species richness increases with increase in soil organic matter, CaCO3 and moisture contents, while decrease with increase in soil pH, total dissolved solids and electrical conductivity (p < 0.05). The vegetation was classified into four major plant communities and their respective indicators were identified using indicator species analysis. Indicator species analysis reflects the indicators of the study area are mostly the indicators to the Himalayan or moist temperate ecosystem. These indicators could be considered for micro-habitat conservation and respective ecosystem management plans not only in the study area but also in other region with similar sort of environmental conditions. [ABSTRACT FROM AUTHOR]

Abstract: The phytosociological attributes of western Himalayan moist temperate forests were investigated in Bagh district, Kashmir. Detailed sampling was carried out in 180 forest stands (30×30m) at 13 sites. Average number of vascular plant species found per site was between 30 and 40; Menhinick’s Richness was 0.93–1.63; Simpson’s Diversity Index between 0.75 and 2.27; Shannon’s Evenness between 0.21 and 0.71; the Maturity Index 38 to 53. Species diversity and community structure patterns were significantly correlated to environmental variables including altitude and slope inclination as well as intensity of anthropogenic pressure. Abies pindrow and Pinus wallichiana showed exclusive dominance comprising 30% of Importance Value Index (IVI) weight age of all 122 recorded species. Forest ground flora was dominated by grasses of the Poaceae. Average tree density was 151ha−1 whereas basal area was estimated as 68.8m2 ha−1. A stem/stump value of 1.62 indicated immense tree felling and logging pressure on local forests. A disturbed forest regeneration pattern was indicated by an average seedling count of 124ha−1. A negative correlation (CCA) was found between diversity and richness with altitudinal gradient as well as slope and aspect. Diversity values were similar, whereas tree density, basal area and seedling count were lower, compared to other Himalayan forest sites. These results indicate a deteriorated forest structure and reduced regeneration pattern, demanding immediate attention of forest management authorities. [Copyright &y& Elsevier]