This study was conducted in a temperate mixed oak–pine forest of Central Himalaya, India to (i) evaluate altitudinal and seasonal variations in the microbial biomass carbon (C), nitrogen (N) and phosphorus (P) and (ii) analyse the relationships between soil microbial biomass C, N and P and physico-chemical properties of soil. Three permanent plots were established in natural forest stands along an altitudinal gradient, three replicates were collected seasonally from each site, and microbial biomass (C, N and P) were determined by a fumigation extraction method. Microbial biomass C, N and P decreased significantly (p < 0.01, correlation coefficient 0.985, 0.963, 0.948, respectively) with increasing altitude having maximum values during rainy season and minimum values during winter season. Microbial biomass C, N and P showed positive correlations with silt particles, water holding capacity, bulk density, soil moisture, organic C, total N and P and negative correlations with sand particles, porosity and soil pH. Microbial biomass C was strongly associated with soil microbial N (r = 0.80, p < 0.01) and P (r = 0.89, p < 0.01) content and soil microbial biomass N and P also showed a strong linear relationship (r = 0.92, p < 0.01). Soil microbial biomass exhibited weak seasonality and was highly influenced by altitude and abiotic variables. The significantly high microbial C, N and P during the rainy season (p < 0.01) and low microbial biomass during the winter season may be due to higher immobilization of nutrients from decomposing litter by microbes as the decomposition rate of litter and microbial activity are at their peak during the rainy period. The microbial C:N ratio indicated that soil fertility is influenced by species composition. Our findings suggested that high microbial biomass and low C:N ratios during the rainy season could be considered a nutrient conservation strategy of temperate mixed oak–pine forest ecosystems.

Rice (Oryza sativa L.) is a staple food for more than half of the world's population. Globally, rice is grown on 161 million hectares, with an average annual production of 678.7 million tonnes. Drought and salinity are two major abiotic determinants due to high magnitude of their impact and wide occurrence. In the present study rice varieties were analyzed for water and salt stress tolerance at germination and early seedling growth stage. Seeds of three rice varieties (Narendra 1, Sabarmati and Hybrid 312) were collected and kept under four water stress and six salt stress levels. Seed germination, seedling length, dry weight, seed vigor and other parameters were recorded. The results showed that with increasing water stress, germination in all the varieties was delayed and decreased from 68.8% in control to 4.4 % in highest stress (-15 bar) level. Dry weight of shoot and root, shoot and root length, fresh weight of stem and root decreased in all rice varieties with the increase in water stress level. Narendra 1 and Sabarmati showed better response while Hybrid 312 failed to germinate in all water stress levels. The increase in salt stress also reduced every measured trait significantly in all the varieties. Seed germination decreased from 100% in control to 65 % in highest (20 ds/m) salt stress level. Maximum germination percentage (100%) was observed in Hybrid 312 under all the salt stress levels. These results could be helpful in identification of the tolerant varieties which can be studied further and economically exploited.

Carbon stock assessment in various ecosystems is vital for monitoring the health of these ecosystems and national accounting for the United Nations convention on climate change. The influence of various anthropogenic drivers on carbon stock in different ecosystems has not been examined comprehensively. This study aims to determine the impact of anthropogenic pressures (lopping, cutting, grazing) on soil physico-chemical properties and carbon stock in four temperate broadleaf forests dominated by different species of oak, viz., Banj oak (Quercus leucotrichophora), Rianj oak (Quercus lanuginosa), Moru oak (Quercus floribunda) and Kharsu oak (Quercus semecarpifolia) along an elevation gradient from 1700–3000 m asl in Gori valley, western Himalaya. Biomass data were collected from 120 quadrats of 10 × 10 m size at three distinct altitudes (4 forest sites × 3 altitudes × 10 quadrats) and analysed for carbon stock, whereas soil samples were randomly collected in triplicate from three depths of each altitude of the forest site and further analysed for their physico-chemical properties. A total of 767 individual trees with a diameter of ≥31 cm were measured at twelve sites and standing biomass was estimated following the growing stock volume equations. Mean carbon stock was highest in Moru oak (396.6 ± 29.5 Mg C ha⁻¹) and lowest in Banj oak forest (189.3 ± 48.6 Mg C ha⁻¹). We also found soil to be the largest pool of forest carbon (43.0–59.7%) followed by aboveground biomass (31.5–45.0%), belowground biomass (8.4–11.7%) and litter (0.4–0.5%). The basal area showed significant effect on altitude and carbon stock, whereas disturbance showed significant (p < 0.05) negative correlation with the total carbon stock. Soil nitrogen exhibited a significant positive correlation (R² = 0.60) with the basal area, indicating that nitrogen enhances tree growth and forest carbon stock. However, anthropogenic disturbance showed a significant negative impact on the basal area, soil nutrients and carbon stock of oak forests. This concludes that forest structure, anthropogenic pressure and soil parameters contribute to the carbon stock of the area. Considering the significance of these overexploited oak forests, it is recommended to conserve the old-growth forest species in the study area, since they have the highest carbon accumulation potential.