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There has been a widespread call for the development of transformative adaptation knowledge and strategies in the Himalayan region because of the intensifying onset of climate change impacts. But such transformative thinking is absent in much of Himalayan climate knowledge production, which builds on environmental deterministic and techno-managerial renditions of exceptional precarity; advocates for an increase in the scientific and expert driven projects on the ground; and remains rooted in the scalar realities of the nation-state. This paper contributes to the rich scholarship that counterbalances depoliticized renditions of climate change adaptation, by presenting "everyday stories of adaptation" that have emerged from the authors' work alongside Himalayan communities. In this work we ask, who is the subject in Himalayan climate adaptation discourse and policies? And how can their stories help us envision an adaptation praxis, which challenges regional narratives of crisis and provides alternatives to climate reductionist thinking/planning, by foregrounding the intersectionality and plurality of communities and ecologies? The stories come from three parts of the Himalaya: Uttarakhand, Khumbu, and Assam, and highlight the daily labor for adaptation and its mercurial relationship with the labor for survival. We find that intertwined with changing climate-society relationships are, historical caste privileges and changing generational relationships to land; the complicated engagements between indigeneity, communal sovereignty, and exclusionary institutional mandates; and life with ethnoreligious othering in an aqueous and geopolitically fluid borderland. Together these stories witness the relational social-ecological worlds of regional inhabitants, challenging their powerless and pejorative depictions through climate reductive framings. We conclude with a set of objectives to enable more hopeful and just adaptation futures. [ABSTRACT FROM AUTHOR]

Plant lifespan has important evolutionary, physiological, and ecological implications related to population persistence, community stability, and resilience to ongoing environmental change impacts. Although biologists have long been puzzled over the extraordinary variation in plant lifespan and its causes, our understanding of interspecific variability in plant lifespan and the key internal and external factors influencing longevity remains limited. Here, we demonstrate the concurrent impacts of environmental, morphological, physiological, and anatomical constraints on interspecific variation in longevity among > 300 vascular dicot plant species naturally occurring at an elevation gradient (2800–6150 m) in the western Himalayas. First, we show that plant longevity (ranging from 1 to 100 years) is largely related to species' habitat preferences. Ecologically stressful habitats such as alpine and subnival host long‐lived species, while productive ruderal and wetland habitats contain a higher proportion of shorter‐lived species. Second, longevity is influenced by growth form with monocarpic forbs having the shortest lifespan and woody shrubs having the highest. Small‐statured cushion plants with compact canopies and deep roots, most found on cold and infertile alpine and subnival soils, had a higher chance of achieving longevity. Third, plant traits reflecting plant adaptations to stress and disturbance affect interspecific differences in plant longevity. We show that longevity and growth are negatively correlated. Slow‐growing species are those that have a higher chance of reaching a high age. Finally, higher longevity was associated with high leaf carbon and phosphorus, low root phosphorus and nitrogen, and with large bark‐xylem ratio. Our findings suggest that plant longevity in high elevation is intricately determined by a combination of habitat preferences and growth form, as well as the plant growth rate and physiological processes. [ABSTRACT FROM AUTHOR]

The alpine butterfly genus Parnassius is a popular model group for studying biogeography, evolution, conservation biology, and ecology. Despite its scientific importance, a comprehensive and robust phylogeny of this group is still lacking. In this study, we used an amplicon capture strategy to sequence 144 nuclear protein‐coding genes and complete mitochondrial genomes for 60 Parnassius specimens covering 42 species and all eight subgenera of Parnassius. Our results strongly support the monophyly of the genus and eight subgenera. The relationships among subgenera are robustly resolved as (Sachaia, (Kreizbergia, (Driopa, (Parnassius, (Tadumia, Lingamius), (Kailasius, Koramius))))), which is different from all previous results. Biogeographic and divergence time analyses indicate that the ancestor of Parnassius originated in an area including the Himalayas and Tibetan Plateau (HTP) and Mongolian steppes in the middle Miocene approximately 13.19 Mya. The middle Miocene global cooling event (starting from ~13.9 Mya) probably provided climatic opportunities for the diversification of cold‐adapted Parnassius. The ancestral state reconstruction analyses suggest that the ancestor of Parnassius butterflies most likely lived in a medium elevational area (2000–4000 m) and fed on Papaveraceae plants. The host shift from Papaveraceae to Crassulaceae in the subgenus Parnassius increases the species diversity of this subgenus, concurring with the "escape and radiate" hypothesis. Overall, our work provides valuable nuclear gene and mitochondrial genome data and a robust phylogenetic framework of Parnassius for future studies of the taxonomy, evolution, and ecology of this group. [ABSTRACT FROM AUTHOR]

In the Himalayas, the lives and livelihoods of millions of people are sustained by water resources primarily depending on the moisture brought by Western Disturbances and Indian Summer Monsoon. In the present study, a network of 12 precipitation stations was established across the Kashmir Valley to understand the spatial and meteorological factors controlling precipitation isotopes. Temperature and relative humidity are dominant meteorological factors, whereas altitude, proximity to forest canopy, land use/land cover, windward and leeward sides of the mountains are the main physical factors influencing precipitation isotopes. The study suggests that the Mediterranean Sea and nearby water bodies along with continental recycling are the dominant sources of moisture from October to May, while the Arabian Sea, Bay of Bengal and continental recycling are the main sources of moisture from June to September. However, some precipitation events from October to May collect moisture from the Arabian Sea and some precipitation events from June to September collect moisture from the Mediterranean Sea. The occasional passage of Western Disturbances in summer merging with the Indian Summer Monsoon yields heavy to very heavy precipitation. The study provides a better understanding of complex spatial and meteorological phenomena controlling precipitation isotopes across the Western Himalayas. [ABSTRACT FROM AUTHOR]

Planctomycetes are common inhabitants of northern wetland ecosystems. In this study, a new planctomycete of the genus Paludisphaera, strain Pla2T, was isolated from a boreal fen in Russia. The novel isolate was represented by nonmotile, pink-pigmented, spherical cells that multiplied by budding and occurred singly or were assembled in small aggregates. Strain Pla2T was a chemoorganotrophic, psychrotolerant mesophile with a growth optimum at pH 5.5‒6 and 15‒20°C. The preferred growth substrates were polysaccharides, including xylan, xanthan gum, and phytagel, as well as some sugars. The 16S rRNA gene sequence of strain Pla2T displayed the highest similarity (97.9%) to that of 'Paludisphaera soli' JC670T isolated from highland soil of the western Himalayas. With other members of the genus Paludisphaera, 'P. rhizosphaerae' JC665T and P. borealis PX4T, this similarity was 97.0 and 93.8%, respectively. The genome of strain Pla2T was 8.21 Mb in size and contained about 6500 protein-coding genes and 3 copies of the rRNA operon. The DNA G + C content was 67 mol %. The average nucleotide identity between the genome sequence of strain Pla2T and those of previously described members of the genus Paludisphaera was between 79.4 and 82.6%. This genotypic distance as well as several phenotypic differences allowed classifying the new planctomycete from a fen as representing a novel species of the genus Paludisphaera, Paludisphaera mucosa sp. nov. with the type strain Pla2T (=KCTC92668T = VKM B-3698T). [ABSTRACT FROM AUTHOR]

Dachigam National Park (DNP), in Zabarwan mountains of north-western Himalaya constitutes a region of high biodiversity with greater endemism. DNP is known for its unique micro-climate together with distinct vegetational zones providing home to variety of threatened and endemic plant, animal, and bird species. However, studies on soil microbial diversity in fragile ecosystems of north-western Himalaya in general and DNP in particular are lacking. This was thus a maiden attempt to study variations in soil bacterial diversity of DNP with respect to changing soil physico-chemical properties, vegetation, and altitude. Soil parameters depicted significant variations among different sites with highest values for temperature, OC, OM and TN being 22.2 ± 0.75 °C, 6.53 ± 0.32%, 11.25 ± 0.54%, 0.545 ± 0.04% from site-2 (low altitudinal grassland site) in summer and lowest of 5.1 ± 0.65 °C, 1.24 ± 0.26%, 2.14 ± 0.45% and 0.132 ± 0.04% at site-9 (high altitudinal mixed pine site) in winter. Bacterial CFU showed significant correlations with soil physico-chemical attributes. This study led to the isolation and identification of 92 morphologically varied bacteria with the highest (15) from site-2 and lowest (04) from site-9 which post BLAST analysis (via 16S rRNA analysis) depicted presence of only 57 distinct bacterial species under taxonomic phylum, Firmicutes and Proteobacteria. Nine species were widely spread (i.e., isolated from > 3 sites), however, most bacteria (37) were restricted to a particular site. Diversity indices ranged between 1.380 to 2.631 (Shannon–Weiner's index); 0.747 to 0.923 (Simpson's index) with highest values for site-2 and lowest for site-9. Index of similarity was highest (47.1%) between riverine sites (site-3 and site-4) whereas two mixed pine sites (site-9 and site-10) showed no similarity. [ABSTRACT FROM AUTHOR]

This paper describes the course of migration and expansion of small mammals in the Makalu Barun region influenced by the orogenetic uplift of the East Nepal Himalaya and climatically conditioned changes in the extent of morphogenetic zones from the Upper Pleistocene up to the present. The results of zoological and parasitological research are compounded with the knowledge of the dynamic development of landforms, which testifies to significant changes in the high-mountain environment during the Quaternary. The migration of Palearctic species of small mammals across the gradually emerging orographical barrier during the orogenesis of the High Himalaya was completely interrupted by the glaciation in the Upper Pleistocene. This extensive glaciation also excluded occurrence and survival of small mammals in the high-mountain valleys of the Makalu Barun region. Migration routes and the extension of the territory of small mammals remained open only in the periglacial zone of the Arun and Barun Khola valleys. Following the interstadial period of warmer and humid climate conditions were changed by the Late Glacial Maximum when small mammals were again pushed away from heavily glaciated valleys to the lower altitude periglacial zone. During the Holocene interglacial, the occurrence of fauna and flora in the high-mountain valleys depended on repeated spatial changes of periglacial and glacial morphoclimatic zones. Current biogeographical hazards are accentuated due to the rapid retreat of glaciers, the expansion of the periglacial morphoclimatic zone and the increased human impact in the High Himalaya. [ABSTRACT FROM AUTHOR]

Throughout the Himalaya, mountain ungulates are threatened by hunting for meat and body parts, habitat loss, and competition with livestock. Accurate population estimates are important for conservation management but most of the available methods to estimate ungulate densities are difficult to implement in mountainous terrain. Here, we tested the efficacy of the recent extension of the point transect method, using camera traps for estimating density of two mountain ungulates: the group-living Himalayan blue sheep or bharal Pseudois nayaur and the solitary Himalayan musk deer Moschus leucogaster. We deployed camera traps in 2017–2018 for the bharal (summer: 21 locations; winter: 25) in the trans-Himalayan region (3,000–5,000 m) and in 2018–2019 for the musk deer (summer: 30 locations; winter: 28) in subalpine habitats (2,500–3,500 m) in the Upper Bhagirathi basin, Uttarakhand, India. Using distance sampling with camera traps, we estimated the bharal population to be 0.51 ± SE 0.1 individuals/km2 (CV = 0.31) in summer and 0.64 ± SE 0.2 individuals/km2 (CV = 0.37) in winter. For musk deer, the estimated density was 0.4 ± SE 0.1 individuals/km2 (CV = 0.34) in summer and 0.1 ± SE 0.05 individuals/km2 (CV = 0.48) in winter. The high variability in these estimates is probably a result of the topography of the landscape and the biology of the species. We discuss the potential application of distance sampling with camera traps to estimate the density of mountain ungulates in remote and rugged terrain, and the limitations of this method. [ABSTRACT FROM AUTHOR]

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]

Altitude is a determining factor of vegetation composition, ecosystem properties and processes, and availability of soil nutrients. Present study examined soil nutrients at two depths i.e. 0–15 cm and 15–30 cm along altitudinal gradients (1800–4000 m asl) in the Indian western Himalaya. Results of the study reveals an increase in organic carbon (OC), total nitrogen (TN), and total potassium (TK) along an altitudinal gradient, indicating that low temperature limits the cycling of organic matter at high altitudes. A significant positive relationship of soil nutrient parameters with altitude was observed for moisture content, OC, TN, TK, C:N ratio; however, it was negatively significant for pH. All the soil nutrients were higher for 0–15 cm depth than 15–30 cm across the altitudinal gradients. The tree species richness decreased with the increasing altitude. TN, OC, and TK were found at maximum levels in a broad-leaved forest (i.e. Betula utilis) at 4000 m, followed by Pinus wallichiana (3600 m) and Abies pindrow (3000 m). This indicates that broad-leaved forests contributed strongly to carbon sink in the high-altitude region of the Himalaya. It is concluded that forest stand structures and abiotic factors govern soil nutrients concentrations along altitudinal gradient in the Himalayan region. [ABSTRACT FROM AUTHOR]

Although vegetation has been the focus of recent studies on mountain summits, little is known about smaller‐scale spatial patterns of soil physico‐chemical properties. Here, we report patterns and drivers of soil physico‐chemical properties and their role in shaping the plant diversity on mountain summits of the Himalaya. Using the globally standardized Multi‐Summit Approach, four summits along an elevation gradient from treeline to nival zone were selected in Kashmir Himalaya. Sampling of the summits was carried out to collect soil samples together with vegetation data and soil temperature. The results revealed that there is a significant effect of elevation and aspect on soil physico‐chemical properties and species richness on the summits. A significant correlation was observed between soil parameters and elevation, indicating that summits with distinct pool of species possess distinct soil properties. Moreover, soil temperature clearly determined the aspect‐wise distribution of soil parameters and species richness. The Canonical Correspondence Analysis revealed that elevation, soil temperature, pH, electrical conductivity and C:N ratio were more prominent in determining the plant diversity on summits. Our results demonstrate that mosaic of micro‐climatic conditions driven by elevation and aspect favor a suite of soil properties, which in turn determine the patterns of species diversity on the mountain summits. The present study, therefore, enhances understanding of the spatial patterns of variation in soil and plant diversity of mountain summits, which will help to monitor, model and predict how these ecologically unique ecosystems will respond to climate warming in the Himalaya, with implications for such environments elsewhere. [ABSTRACT FROM AUTHOR]

Variation in fine root biomass (FRB) and turnover rate (TOR) were examined in four land use systems at two altitudes by using ingrowth core method. The aim of the study was to analyse the effect of altitude, depth and distance from tree stem on FRB and TOR. Significant variations (p < 0.05) were observed among land use systems, over seasons, depth and distances from the tree stem. The FRB varied between 47.09 and 528.59 kg ha–1. It was maximum in agri-horticulture (AH) system in bhabhar region and in homegarden (HG) system in hill region. In each land use system at both the altitudes FRB was maximum at uppermost layer (0‒20 cm) during rainy season at 50 cm distance from tree stem while, TOR did not showed any particular trend with soil depth and distance from the tree bole. FRB and turnover rate showed significance correlation with distance from tree bole at both the altitudes i.e. (r2 = 0.898 for low and r2 = 0.899 for high altitude). [ABSTRACT FROM AUTHOR]

At a global scale, heat deficits during the growing season result in growth limitations, which determine the elevation of natural alpine treelines. Thus, the expected response to global warming is a treeline advance to higher elevations. However, empirical studies of diverse mountain ranges have yielded evidence of both advancing alpine treelines as well as rather insignificant responses. Based on an extensive collection of field data, we analysed population structures and regeneration patterns, investigated population density-environment relationships and correlated tree growth with climate in order to assess the sensitivity to climate warming of a near-natural treeline ecotone in east-central Nepal. The presence of an elevational zone dominated by a gnarled growth form of Rhododendron campanulatum physiognomically classifies the treeline as a krummholz treeline. The fraction of juvenile tree individuals reflects prolific regeneration and stand densification. The species-specific variation in adult and juvenile stand density along the treeline ecotone depends not only on temperature but also on soil, topographic, and other microclimatic conditions. Rhododendron campanulatum shows highest competitiveness in the krummholz belt under a constellation of site conditions influenced by this species itself. By contrast, Abies spectabilis (Himalayan Silver Fir) and Betula utilis (Himalayan Birch) have gained predominance under warmer and more nutrient-rich habitat conditions in the closed forest below. The dense krummholz belt effectively controls the potential upslope migration of subalpine forest tree species. Abies spectabilis growth-climate correlations show changing growth limitations in the course of the 20th century, most likely due to intensified climate warming in recent decades, when decreasing moisture availability during the pre-monsoon season has affected Abies spectabilis' radial growth. It is evident from our results that to date the treeline has responded to climate warming in terms of stand densities, seed-based regeneration and growth patterns of trees, the treeline position, however, is rather stable. A treeline shift is to be expected in the mid- to long-term only. [ABSTRACT FROM AUTHOR]

Post-glacial geomorphological settings bearing great amounts of colluvium as well as alluvial and moraine deposits are typical features in high mountainous environments such as the Himalayas, the Hindu Kush, the Pamirs, the Karakorum and the Tien Shan Mountains. Due to a lack of alternative living space in narrow valleys, agglomerations are often located on these unstable grounds and regularly experience dislocations across the ground surface and subsequent damage to building stock and infrastructure. Hosting two post-glacial landslide deposits and one gravitational creep within its inhabited areas, the village of Tusion, South-Western Tajikistan, was chosen to conduct geophysical surveys with the aim to determine the geomorphological causes of regularly experienced slope deformations with particular interest in the contribution of non-isolated irrigation channels crossing the mountain flanks. Over the last two decades uncontrolled seepage from a network of small-scale waterways is believed to be responsible for water infiltration to deeper horizons and - thereby - reactivate ancient sliding surfaces within the two landslide deposit zones. Also, the gravitational creep in one village part seems to be likewise triggered. Using refraction seismics and Schlumberger geoelectrics, stratigraphic structures, properties of involved rock material and saturation patterns were assessed in order to provide complementary information about the underground of concerned slopes to a previously conducted hazard assessment by separate Non-Governmental Organizations. Results of the geophysical surveys show conclusive correlations with the hazard maps and local damage reports straining that one of the major destabilizing factors for all concerned slopes consists of uncontrolled water dissipation to the underground. [ABSTRACT FROM AUTHOR]

Despite constituting important ecosystem of Kashmir Himalaya and being sensitive to climate change, data on soil organic carbon (SOC) in grasslands remain scarce. Present study was conducted in 20 grasslands that represent pasture and non-pasture types, with an aim to record SOC stocks at 5 sampling depths (0–10; 10–20; 20–30; 30–40 and 40–50cm), study its variation along altitude and elucidate how environmental factors affect this variation. SOC stocks exhibited high variability and ranged between 28.85 and 94.76 Mg C ha−1, with mean value of 54.52 Mg C ha−1, which was stored as 30.63, 22.98, 21.06, 14.89, and 10.41%, respectively at five depths. Differences in SOC stocks between pasture and non-pasture types were minor, with average stocks appearing slightly higher for pasture (59.69 ± 15.43 Mg C ha−1) than non-pasture (56.32 ± 17.01 Mg C ha−1). However non-pasture type had higher stocks particularly in upper soil layers. SOC exhibited negative relationship with soil depth and bulk density while increasing relationship with altitude, species richness and aboveground live and dead biomass was observed. On depth gradient, altitude affected subsurface (10–20cm) soils more distinctly than surface (0–10 cm) soils. Besides contributing baseline data, comparison of SOC provides possibility to determine management effects on SOC storage and consequently C sequestration. [ABSTRACT FROM AUTHOR]

[Display omitted] • The evolutionary history of Pleione was investigated using single-copy gene single nucleotide polymorphisms and chloroplast genome datasets. The data revealed that Pleione can be divided into five clades. • Ancestral area reconstruction suggested that Pleione likely originated from the HDM. The uplifting of the HDM drove rapid diversification by creating conditions favoring rapid speciation. This coincided with two periods of strengthening of the Asian monsoon climate, which caused the first rapid diversification of Pleione from 8.87 to 7.83 Mya, and a second rapid diversification started at around 4.05 Mya to Pleistocene. • In addition to revealing the evolutionary relationship of Pleione with orogeny and climate changes, the findings provide insights into the speciation and diversification mechanisms of plants in the East Asian flora. Pleione is an orchid endemically distributed in high mountain areas across the Hengduan Mountains (HDM), Himalayas, Southeast Asia and South of China. The unique flower shapes, rich colors and immense medicinal importance of Pleione are valuable ornamental and economic resources. However, the phylogenetic relationships and evolutionary history of the genus have not yet been comprehensively resolved. Here, the evolutionary history of Pleione was investigated using single-copy gene single nucleotide polymorphisms and chloroplast genome datasets. The data revealed that Pleione could be divided into five clades. Discordance in topology between the two phylogenetic trees and network and D -statistic analyses indicated the occurrence of reticulate evolution in the genus. The evolution could be attributed to introgression and incomplete lineage sorting. Ancestral area reconstruction suggested that Pleione was originated from the HDM. Uplifting of the HDM drove rapid diversification by creating conditions favoring rapid speciation. This coincided with two periods of consolidation of the Asian monsoon climate, which caused the first rapid diversification of Pleione from 8.87 to 7.83 Mya, and a second rapid diversification started at around 4.05 Mya to Pleistocene. The interaction between Pleione and climate changes, especially the monsoons, led to the current distribution pattern and shaped the dormancy characteristic of the different clades. In addition to revealing the evolutionary relationship of Pleione with orogeny and climate changes, the findings of this study provide insights into the speciation and diversification mechanisms of plants in the East Asian flora. [ABSTRACT FROM AUTHOR]

In an era of global environmental change, conservation of threatened biodiversity and ecosystem restoration are formidable ecological challenges. The forest understory strata and the belowground soil environment including rhizospheric microbial communities, which are crucial for ecosystem functioning and overall forest biodiversity maintenance, have remained understudied. Here, we investigate the soil microbiome of Trillium govanianum – an endangered Himalayan Forest herb, to unravel the underground diversity, drivers, and potential indicators of the microbial community. We collected rhizospheric and bulk soil samples for microbiome and physicochemical analysis at three sites along an elevation gradient (2500–3300 m) in Kashmir Himalaya. Amplicon sequencing of 16 S rRNA and ITS was used to identify the bacterial and fungal soil microorganisms. We found significant differences in the structure and diversity of microbial community (bacterial and fungal) between the rhizosphere and bulk soil along the altitudinal gradient, and noticeable shifts in the nutrient level in dominant microbial phyla associated with T. govanianum. A significant difference between soil physicochemical parameters and increasing altitude suggests that microbial community structure is determined by altitude and soil type. Similarly, the microbial communities showed a significant (P < 0.05) correlation with soil physicochemical variables along the altitudinal gradient. The moisture content in bacterial and total organic carbon in fungal communities showed the most substantial impact on the physiochemical drivers. We also identify potential bacterial and fungal plant growth promoter indicator species in the soil microbiome of T. govanianum. Overall, our findings provide novel research insights that can be pivotal in designing integrated species recovery programs and long-term restoration plans for T. govanianum, with learnings for biodiversity conservation elsewhere. • Soil microbiome of Trillium govanianum studied to unravel its diversity, drivers and indicator species. • Soil microbial communities showed significant differences in the abundance and diversity. • Physicochemical drivers of soil microbiome differ with increase in altitude. • Significant correlation observed between soil microbial communities and physicochemical drivers. • Bacterial and fungal plant growth promoter indicator species identified. [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]

The western Siwalik Himalayas of India experienced the last climate shift 3500 years ago and the soils have been marked by rigorous human activities for a few centuries. An attempt was made to investigate the interactions between soil-forming factors and processes in soil development in relation to land forms and climate change. The hallmark of the soils is the considerable heterogeneity in solum and regolith thickness, horizon boundaries, structural development in surface soils, pH, electrical conductivity and soil mineralogy, irrespective of landscape form and position. A remarkable feature of the soils is the development of deep argillic horizons, or B horizons, in certain landscape positions. The minerals identified were quartz, micas and feldspars in the sand and silt fractions. Illite, kaolinite, vermiculite, smectite and chlorite were present in the clay fractions. Soils under forest vegetation and those recently brought under cultivation belong to Typic Hapludalfs. Soils cultivated over centuries, however, failed to qualify as Alfisols and were classified as Typic/Dystric Eutrudepts. The eroded barren soils were similarly classified as Typic Udorthents. All the soils were low to medium in available nitrogen and phosphorus. The use of nitrogen and phosphorus fertilizer is therefore needed to ameliorate nutrient deficiency and boost crop production. Because of the presence of appreciable amounts of potassium-bearing minerals, soils are likely to be non-responsive to potassium application. The soils of the Dala series (Typic Hapludalfs) are located on moderate hill slopes and thus soil erosion is less severe than for the Mansu series (Typic Udorthent). In the Chamror and Dhar series (Typic/Dystric Eutrudepts) soil erosion is not a serious problem because of terracing and the finer texture of the soils. Crops can thus be grown on profile-stored moisture during dry periods and limited grazing may be permitted. [ABSTRACT FROM AUTHOR]

Spatial distribution of potassium in mountain soils is governed by landforms, as the operational intensity of factors and processes of soil formation vary with landforms. Therefore, we aimed to find out the relationship between potassium (K) fractions with landforms and the association of K fractions with soil properties. For this, horizon-wise soil samples were collected from pedons, one each from six topographic positions in a catena in the Punjab Himalayas. Samples were analysed for physical and chemical properties and for K fractions. The soils were alkaline and calcareous. The water soluble-K ranged between 4.0 and 18.5 mg kg-1 , exchangeable K between 27.3 and 292.2 mg kg-1, fixed K from 392-240 mg kg-1, and total K from 1.1-3.1%. All forms of K were positively related to silt and negatively to sand. Exchangeable and total forms of K were positively correlated with clay and CEC. The trends could be corroborated with mineralogy, which are rich in K-bearing minerals like micas and feldspars in coarse fractions and illites in clay fractions. The positive coefficients of correlation amongst the forms of K suggest that K forms are present in dynamic equilibria. The spatial distribution of K fractions was closely associated with landforms. [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]