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Superoxide dismutases are the enzymes involved in dismutation of superoxide radicals into oxygen and hydrogen peroxide. The present work reports a thermostable Fe/Mn SOD of Geobacillus sp. strain PCH100 (GsSOD) isolated from glacial soil. Purified recombinant GsSOD is a dimeric protein of ~57 kDa that exhibited highest activity at a temperature of 10 °C and pH of 7.8. Maximum enzyme velocity and Michaelis constant of the GsSOD were 1098.90 units/mg and 0.62 μM, respectively. At 80 °C, thermal inactivation rate constant and half-life of GsSOD were 3.33 × 10−3 min−1 and 208 min, respectively. Interestingly, GsSOD tolerated a temperature of 100 °C and 130 °C up to 15 min and 5 min, respectively. Circular dichroism and differential scanning calorimetry confirmed thermostable nature of GsSOD. Apoenzyme of GsSOD regained enzymatic activity in the presence of Fe2+ and Mn2+ as metal ion cofactors. GsSOD was stable under varying concentrations of chemicals, namely ethylenediaminetetraacetic acid, potassium cyanide, hydrogen peroxide, chloroform-ethanol, 3-[(3-cholamidopropyl)-dimethylammonio]-1-propanesulfonate, Tween-20, Triton X-100, urea, and guanidine hydrochloride. The enzyme exhibited >70% activity in presence of 10 mM metal ions. Owing to its thermostable nature and resistance to chemical inhibitors, GsSOD is a potential enzyme for industrial applications. • A thermostable SOD from Geobacillus sp. (GsSOD) was cloned and expressed in E. coli. • The V max and K m for GsSOD were 1098.90 units/mg and 0.62 μM, respectively. • GsSOD exhibited activity at wide range of pH, temperatures, and common inhibitors. • At 80 °C, K d and t 1/2 of GsSOD were 3.33 × 10−3 min−1 and 208 min, respectively. • CD spectroscopy and DSC validated thermal stability of GsSOD. [ABSTRACT FROM AUTHOR]

• Throughfall exclusion did not impose tree mortality, but reduced stem increment. • Reduced soil moisture sharply decreased soil CO2 efflux. • Fine root biomass remained largely unaffected. • Himalayan mountain forests showed overall high resistance to throughfall exclusion. Forests in the Himalayas are a major carbon store, but are under threat due to changes in precipitation regime. To simulate a precipitation decline, throughfall-exclusion (TFE) shelters were applied during three consecutive monsoon seasons in an oak forest (2.650 m a.s.l.) and a conifer-dominated forest (3.260 m a.s.l.) in central Bhutan. Leaf water potentials, tree mortality, stem increment, soil CO 2 efflux, litterfall and fine root dynamics were assessed. TFE significantly and consistently decreased topsoil (0–30 cm) moisture and leaf water potentials of Quercus lanata and Quercus griffithii (lower elevation), and to a lesser extend those of Tsuga dumosa and Quercus semecarpifolia , (higher elevation). TFE did not impose tree mortality. Stem increment remained unaffected until the second TFE year, but showed reductions during the third year with Tsuga dumosa being most severely affected (-60%). Standing fine root biomass stocks were hardly affected by TFE. Increased root necromass and faster fine root growth in the lower elevation forest suggest that the oak trees increased C allocation below ground. Soil CO 2 efflux sharply declined during all three TFE years in both forests. Above ground litter input was unaffected by TFE until the second treatment year. Overall, both forest ecosystems appeared highly resistant to the imposed soil drying, with no signs of tree mortality and stable living root biomass stocks. [ABSTRACT FROM AUTHOR]

• Agroforestry forms an explicit part of the hill farming systems. • Mostly all the dominant agroforestry systems were prevalent in the study area. • Silvopastoral and agrohortosilviculture have the highest CO 2 mitigation potential. • Along elevation, the highest total carbon stock was recorded in Zone III. The estimation of carbon stock in agroforestry is crucial for curbing the global climate crisis. In this study, biomass production and carbon storage potential of the prevalent agroforestry systems along an altitudinal gradient in the Chamba district of Himachal Pradesh was carried out during 2019–2021. Agroforestry practices were categorized into eight land use systems viz., agrisilviculture, agrihorticulture, agrosilvohorticulture, agrohortisilviculture, hortiagriculture, silvopastoral, pastoralsilviculture and hortipastoral systems and were divided into four altitudinal ranges viz., <1000 m above sea level (m asl; Z-I), 1000–1500 m asl (Z-II), 1500–2500 m asl (Z-III) and > 2500 m asl (Z-IV). Results revealed that biomass production and total carbon storage (vegetation + soil) were significantly affected by the land use type along the altitudinal gradient. Among the different agroforestry systems, maximum aboveground biomass (47.48 Mg ha−1) and belowground biomass (12.20 Mg ha−1) were recorded for agrohortisilviculture. Biomass production was positively correlated with altitudes and increased with an increase in altitudes. Soil carbon density was the maximum (35.77 Mg ha−1) under silvopastoral showing a decreasing trend along the altitudinal gradient. The total carbon storage potential was observed the maximum (59.76 Mg ha−1) under silvopastoral system followed by agrohortisilvicuture > agrosilvohorticulture > agrisilviculture > pastoralsilviculture > hortiagriculture > hortipastoral > agrihorticulture. Along the elevation gradient, total carbon stock ranged from 43.99 to 51.13 Mg ha−1 with the maximum carbon stock corresponding to Z-III and the minimum for Z-IV. This study offers a useful approach for selecting different land use systems and vegetation patterns to maximize thecarbon stocks in a cost-effective manner, which will further help to mitigate global warming issues in other fragile Himalayan catchments. [ABSTRACT FROM AUTHOR]

• The soil stoichiometric ratios (C:N:P) were invariant in lower Himalaya. • The studied region has low C:N ratio indicating prospect for N 2 O emission. • Abies species have a higher C sequestration potential and carbon credit. • The findings are helpful to understand nutrient dynamics in forest. Understating of forest functioning is crucial for ensuring the sustainable flow of forest ecosystem services. Climate regulation service of a forest ecosystem can be ensured through emission reduction by increasing carbon sequestration in forests. However, understanding about the functioning of forests for carbon sequestration is constrained due to lack of information on nutrient stocks and stoichiometry of soils of forests of India. Present study focuses to examine the stoichiometry of major nutrients; nitrogen (N), phosphorus (P), carbon (C) of forest soil to understand the dynamics of the forests of Uttarakhand, India. The study also attempted to supplement the information about the soil carbon sequestration potential of important tree species of the forest. Soil samples were collected randomly for the evaluation of physico-chemical characteristics and stoichiometry of forest soil at four altitudinal ranges i.e., <1000, 1000–1500, 1500–2000, and >2000 m a.s.l in the Himalayan region of Uttarakhand, India. The analysis shows that total nitrogen, total phosphorous, and soil organic carbon contents in forest soil were 0.35 ± 0.11%, 0.10 ± 0.04% and 3.36 ± 0.84%, respectively, which increases with altitude. The stoichiometric ratios viz., C:N:P, N:P, C:N, and C:P, and N:P were reported of 51.6:5.4:1, 4.30 ± 2.39, 9.60 ± 1.48, and 41.94 ± 23.35, respectively which were invariant with altitude. The low C:N ratio may be attributed to either increase in the nitrous oxide (N 2 O) emissions with an increase in nitrogen, or low in carbon stock leading to decrease in carbon dioxide (CO 2) and methane (CH 4) emissions. Moreover, the soil C sequestration potential in the forest tree species follow the order of Abies pindrow > Cedrus deodara > Quercus leucotrichophora > Pinus roxburghii. The information of the study would facilitate for broadening the understanding about the soil properties and stoichiometry of forest ecosystem and would provide an aid to forest management besides contributing to the mitigations strategies of the forests. [ABSTRACT FROM AUTHOR]

• Natural factors override land-use impact on streams in the Himalayas. • Effects of 30–40% deforestation of mountain catchments propagate downstream. • Land use in the Himalayas affects streams over a dozen kilometers in the piedmont. • Erosion control in the Himalayas can reduce the flood hazard in the piedmont. Three pairs of small, fourth- to sixth-order catchments (approximately 5–80 km2), draining the margin of the Darjeeling Himalayas into the piedmont, were selected for a comparison of the land-use impact on the morphology and sedimentology of their stream channels. Each pair experienced similar annual rainfall and comprised similar metamorphic bedrock, steep topography, and brown soils; the members of each pair contrast with respect to their land-use structure as they comprise large forest cover (forest >90%) and a significant contribution of agricultural land with tea plantations (forest <63%), respectively. A set of rainfall, cross-sectional, and sediment data were collected for the characterization of the stream channels. The obtained results revealed that, under extreme rainfall and high denudation rates as well as frequent flash floods, the geomorphic response to land-use changes involving agricultural expansion at the expense of forest cover was less pronounced in the mountain channels than in the piedmont. Significant differences between the studied pairs of mountain streams draining forested and agricultural catchments were observed only at bankfull width and baseflow depth in fourth-order streams and baseflow depth in fifth-order streams. Local environmental factors such as bedrock channel boundaries, steep topography, high material supply to river networks, and selective sediment mobilization during extreme rainfall and floods override the effects of land use and exert dominant control over stream channels in mountain catchments. However, the effects of agricultural activity in mountains are propagated downstream. In the agricultural catchment in the piedmont, a local rapid decrease in river slope and an increase in water infiltration into alluvia facilitates the deposition of eroded material. In addition, the stream in the agricultural catchment exhibited a rise in the riverbed with the expansion of a braided channel over a dozen kilometers below the Himalayan front in the piedmont, while the streams in the forested catchment revealed a distinct tendency towards incision. The present-day channel morphologies and sediment patterns observed in forested catchments are most likely similar to those that existed in the studied rivers prior to the development of tea plantations and settlements in the mid-19th century. [ABSTRACT FROM AUTHOR]

• Productivity parameters of Cedrus deodara forests decreases with altitude. • Biomass and soil carbon of Cedrus deodara forests decreases with altitude. • Litterfall production also decreased with altitude. Carbon inventories are urgently needed for understanding climate dynamics and implementing climate mitigation strategies, but such data is scarce in for forest ecosystem of Himalaya. Therefore, the present study focuses to supplement the existing information by estimating carbon stocks in temperate forests dominated by Cedrus deodara along the altitudinal gradients in the Central Himalaya. Three altitudes i.e., lower (1750 m), middle (1900 m) and upper (2050 m) of the stand was considered to understand and estimate biomass and soil carbon storage potential of the forests based on the standard protocol. The results showed that the soil carbon stock (SOC) decreased significantly with increasing soil depths and altitudes. Litterfall production in the forests varied adversely with altitude. Above and below-ground biomass carbon stock also decreased along with altitude. The study observed that the total carbon stock (soil, trees and forest floor) of the Cedrus deodara forest in different altitudes was 395.4 t ha−1 (lower altitude), 321.6 t ha−1 (middle altitude) and 282.5 t ha−1 (upper altitude). The estimates of the Cedrus forests would provide guidelines for estimating carbon for forest-based mitigation activities in the Himalayan region. [ABSTRACT FROM AUTHOR]