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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]

Consumption of high fluoride (F - ) and nitrate (NO 3 - ) containing water may pose serious health hazards. One hundred sixty-one groundwater samples were collected from drinking wells in Khushab district, Punjab Province, Pakistan, to determine the causes of elevated F - and NO 3 - concentrations, and to estimate the human health risks posed by groundwater contamination. The results showed pH of the groundwater samples ranged from slightly neutral to alkaline, and Na + and HCO 3 - ions dominated the groundwater. Piper diagram and bivariate plots indicated that the key factors regulating groundwater hydrochemistry were weathering of silicates, dissolution of evaporates, evaporation, cation exchange, and anthropogenic activities. The F - content of groundwater ranged from 0.06 to 7.9 mg/L, and 25.46% of groundwater samples contained high-level fluoride concentration (F -  > 1.5 mg/L), which exceeds the (WHO Guidelines for drinking-water quality: incorporating the first and second addenda, WHO, Geneva, 2022) guidelines of drinking-water quality. Inverse geochemical modeling indicates that weathering and dissolution of fluoride-rich minerals were the primary causes of F - in groundwater. High F - can be attributed to low concentration of calcium-containing minerals along the flow path. The concentrations of NO 3 - in groundwater varied from 0.1 to 70 mg/L; some samples are slightly exceeding the (WHO Guidelines for drinking-water quality: incorporating the first and second addenda, WHO, Geneva, 2022) guidelines for drinking-water quality. Elevated NO 3 - content was attributed to the anthropogenic activities revealed by PCA analysis. The high levels of nitrates found in the study region are a result of various human-caused factors, including leaks from septic systems, the use of nitrogen-rich fertilizers, and waste from households, farming operations, and livestock. The hazard quotient (HQ) and total hazard index (THI) of F - and NO 3 - showed high non-carcinogenic risk (> 1) via groundwater consumption, demonstrating a high potential risk to the local population. This study is significant because it is the most comprehensive examination of water quality, groundwater hydrogeochemistry, and health risk assessment in the Khushab district to date, and it will serve as a baseline for future studies. Some sustainable measures are urgent to reduce the F - and NO 3 - content in the groundwater., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)