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The article discusses the development of a landslide prediction model for the North-West Himalayas region, discussing the geological conditions, triggers, and correlations between rainfall and landslides, with potential applications in assessing landslide risk and early warning systems in the area.

Sediments released from high altitude glaciers exhibit varying evacuation patterns and transport characteristics owing to the presence of thick debris cover over the glacier. Despite the recent needs for integrated hydrometeorological studies in the Himalaya, little is known about the impacts of suspended sediment on hydropower generation, reservoir sedimentation, and abrasion of turbine components. Present study involves analysis of particle size distribution of suspended sediments to understand sediment evacuation patterns and transport characteristics in variable energy conditions during the ablation season. Peak suspended sediments were evacuated during extreme rainfall events. The estimated seasonal modern sediment erosion rate varies from 0.6 to 2.3 mm y − 1 for the study period (2009–2012). The analysis shows dominance of medium silt-sized to fine sand-sized particles having sediment size of 0.0156–0.25 mm corresponding to 70–80% without any significant seasonal variation. These transported sediments show that they are poorly sorted, coarser in nature with a nearly symmetrical to coarse skewed texture and kurtosis analysis suggesting mesokurtic distribution of sediments. The particle size fraction ranges between 4.65 and 5.23 ϕ , which is dominantly medium to coarse silty in texture. Results indicate that suspended sediments are evacuated in highly variable energy conditions through subglacial transport pathways because of increase in availability of meltwater with the progressive ablation season. Bulk geochemical characterization has been carried out to differentiate the source of suspended sediments and intensity of weathering. Chemical Index of Alterations (CIA) values of sediment flux range from 54.68 to 55.18 compared to the Upper Continental Crust (UCC) ~ 50, indicating moderate intensity of weathering. Mean seasonal (2009–2012) elemental fluxes and their contribution to the suspended sediment flux reflect that Si and Al are responsible for about 85% of the total detrital elemental flux. Trace elements show high concentrations of radioactive elements like U, Th, Pb, and Rb that suggest their high anomalous presence in the catchment lithology. An overall study indicates that the hydroclimatic conditions over the debris-covered glacier play a dominant controlling factor in erosion, transportation, and evacuation of suspended sediments during the ablation season. [ABSTRACT FROM AUTHOR]

Abstract: Proglacial meltwater streams draining out of the Himalayan glaciers carry considerable amounts of suspended sediment, with a variety of particle sizes, because of the supraglacial, englacial, and subglacial debris, as well as formation of sediments from erosion by the movement of the ice. This paper examines particle size transported in the proglacial meltwater stream of Gangotri Glacier for seven consecutive melt seasons (May–October, 2000–2006) in order to provide information on (i) temporal variations in the particle size distribution, (ii) texture and mineralogy of the sediments, and (iii) origin and evacuation pattern of the sediments. Our results indicate dominance of silt size (0.002–0.06mm) particles (71%) followed by sand size (0.06–0.6mm) particles (24%) and clay size (<0.002mm) particles (5%) during the melt season, with increased variation as melt season progresses. The sediment contains quartz, feldspar, mica, illite, and kaolinite minerals, which represent a poor to poorly sorted fraction with a coarse to fine skewed textural distribution. Overall, this study indicates a subglacial evacuation pattern of the suspended sediment based on (i) size classification, (ii) higher percentage of coarser particles toward the end of the melting season, (iii) symmetrical to positively skewed with a kurtosis of mesokurtic to platykurtic texture, and (iv) a less-rounded shape of particle size. Our result on the evolution of meltwater pathways indicates a progressively better interconnected drainage system with advancing melt season. The evolution of meltwater pathways also demonstrates complex behavior of the glacial system and the need for a better understanding of sediment availability and contribution. [ABSTRACT FROM AUTHOR]

Surface wave dispersion data is used to infer the shear wave velocity structure variation in the north‐east Himalaya and Indo‐Burmese arc regions. We have used 25 earthquakes data from four groups with a magnitude range of 5.0–6.7, epicentral distance range 368–800 km, and focal depth less than 50 km. Ray paths from the earthquake location to the seismic station are transversely passing different geotectonic units of the Himalayas, Indo‐Gangetic plains, and Indo‐Burma collision zones. The weighted average dispersion curve and the path averaged shear wave velocity models are computed for the four groups located at different azimuths around Shillong seismic station. Non‐linear least‐square inversion is performed to obtain the shear wave velocity structure of the crust and uppermost mantle from joint inversion of Rayleigh and Love waves group velocities. Subsequently, Rayleigh and Love waves group velocities are inverted separately to obtain vertical and horizontal components of S‐wave velocity. Next, using these components anisotropy coefficient values at different depths for each path are also estimated. A high variation of dispersion curves and the shear wave velocity models from one group to another indicates that the region is geotectonically very complex. An approximately 80 km‐thick zone beneath the study region has shear wave velocity as low as 1.7 km/s in the uppermost crust in the southern part and ~4.7 km in the uppermost mantle beneath the Eastern Himalayan Syntaxis (EHS). Inferred velocity is also lower than that of PREM and AK135 global models with a much thicker crust beneath the study region. Radial anisotropy varies even within the northern part from the Indo‐Eurasian collision zone to EHS and northern to southern Indo‐Burma ranges. Anisotropy is comparatively stronger in the deeper part below ~40 km for the three paths, except for the EHS, where the result is contrary. [ABSTRACT FROM AUTHOR]

The article presents information on biogeographic delineation of the Indian Himalayan Region for configuring, locating and maintaining the protected natural areas . Topics include the recognition of three hierarchical regions which include biogeographic zone, the biotic province and sub-regions, its vegetation being sparse and treeless, and tits fauna including wild species as snow leopard, Himalayan marmot, ans Tibetan woolly hare.

On 7 February 2021 at 10:30 am, a huge amount of slurry material flooded the Rishiganga catchment, resulting in excessive flow along the valley. The main cause of this flood was the dislocation of a huge rock mass approximately 540 m wide and 720 m long from the main rock body, which slipped down towards the Raunthi Gadera valley floor, causing massive devastation in the areas such as Raini, Tapovan, and Vishnuprayag. This event was not expected and was the first event in history when a flash flood occurred in winter. In this study, we tried to answer two major questions which are not been explained so far that are related to this disaster. These questions are (i) why did this event occur in winters? (ii) where did so much debris and water come from?. This study clearly answers these questions based on field observations. [ABSTRACT FROM AUTHOR]

Nitrous-oxide emission and nitrate addition from agriculture to earth's environment are two main agriculture related anthropogenic causes of environmental degradation that needs greater attention. For addressing the aforesaid issue, new techniques/practices need to be developed and implemented. The present investigation, which was focused on this issue, resulted in developing a new mode of nitrogen (N) placement, i.e. 'mid rib placement upper to corms in two splits (MRPU-2S)', that could reduce nitrous oxide N emission by around 70.11% and, nitrate N leaching and runoff by around 68.26 and 67.09%, respectively, over conventional method, in saffron growing soils of northwest Himalayas. Besides plummeting environmental degradation, MRPU-2S further resulted in enhancing saffron yield by 33.33% over conventional method. The findings of the present investigation were used to develop new empirical models for predicting saffron yield, nitrate N leaching and nitrous-oxide N emission. The threshold limits of nitrate N leaching and nitrous oxide N emission have also been reported exclusively in the present study. [ABSTRACT FROM AUTHOR]

The ever-increasing vehicle counts have resulted in a significant increase in air pollution impacting human and natural ecosystems including trees, and physical properties. Roadside plantations often act as a first defense line against the vehicular emissions to mitigate the impacts of pollutants. However, they are themselves vulnerable to these pollutants with varying levels of tolerance capacity. This demands a scientific investigation to assess the role of roadside plantation for better management and planning for urban sprawl where selected trees could be grown to mitigate the impacts of harmful pollutants. The present study assesses the impacts of vehicular emissions on the adaptation and mitigation potential of two important roadside tree species i.e. Grevillea robusta and Mangifera indica planted along roadsides in the capital city of Uttarakhand. Uttarakhand is one of the Indian Western Himalayan State and its capital city is situated on the foothills of Himalaya. The adaptation and mitigation potential were evaluated by studying the response of pollutants on the functional traits which drive the physiology of the trees. The CO2 assimilation rate, transpiration rate, stomatal conductance, water use efficiency (WUE), air pollution tolerance index (APTI), copper and proline accumulation, dust removal efficiency (DRE), leaf thickness and cooling created by plantation were studied to evaluate the response of trees exposed to roadside traffics. To compare the influence of pollutants, traits of trees grown in a control site with few or absence of vehicular movement were compared with the roadside trees. The control site represented part of a reserve forest where human interference is controlled and human-induced activities are prohibited. The vehicular frequency was found to modulate tree characteristics. The tree characteristics representing WUE, APTI, proline and copper accumulation, leaf thickness, cooling impact, and DRE were enhanced significantly, while the decreased CO2 assimilation rate was observed near roadside trees compared to the control site. We found both of the species to perform well to be used as one of the potential species for roadside and urban greening. However, there is a need to assess the potential of other species in reference to the present study. [ABSTRACT FROM AUTHOR]

The article discuss the need of strategic environmental assessment of hydropower projects in India, to meet the demand and supply of energy. It mentions needs of harnessing hydropower projects in Indian Himalayan Region for maximum economic development. It discusses strategic plan for the future development of hydropower projects.

Identifying the new tree crop combinations plays an important function in transforming the low input agriculture into land units with high economic returns, increasing carbon (C) sink and nutrients storage capacity, and acting as a panacea to achieve Sustainability Development Goals (SDGs). The present study aims to evaluate various tree-crop combinations for (i) biomass production, (ii) carbon accumulation, and (iii) soil nutrient enrichment of traditional and commercially evolved eight agroforestry systems (AFSs), including agri-silvi-horticulture system, agri-silviculture system, silvi-pasture, fruit tree, fodder tree, bamboo, melia and poplar based AFSs with sole cropping system in the mid-hill zone of the north-western Himalaya. The results demonstrated that poplar based AFS accumulated a higher amount of biomass (130.87 Mg ha−1) and carbon (65.44 Mg ha−1) closely followed by melia-based AFS. The C stored in leaf litter was higher (0.66 Mg ha−1) in poplar-based AFS, however, soil C stock was maximum (114.69 Mg ha−1) under bamboo-based AFS. Overall, the Melia based AFS exhibited a higher rate of carbon dioxide mitigation (19.30 Mg ha−1 yr−1) and C-sequestration (5.26 Mg ha−1 yr−1) than other studied AFSs. Moreover, soil macro-nutrients (available N, P, K, S and Ca) were maximum under bamboo-based AFS, on the other hand, the fruit-based AFS had the higher concentrations of micro-nutrients i.e., Cu (3.05), Fe (31.10 mg g−1) and Mn (17.31 mg g−1). The soil microbial counts were higher in poplar-based AFS, whereas, the soil quality index improved significantly under bamboo based and fruit tree based AFSs. Hence, it can be concluded that the experimentally evolved AFSs represent an effective approach for boosting C-sequestration, soil fertility, regenerating the soil and sustainability of hill agriculture in the north-western Himalayas over traditional AFSs and sole cropping. • Agroforestry systems (AFSs) contribute significantly to biomass production & carbon storage. • Poplar- and bamboo based AFSs accumulated maximum biomass & soil C stock, respectively. • Melia based AFSs exhibited highest rate of C-sequestration. • Bamboo based AFSs maintained the highest soil quality index. [ABSTRACT FROM AUTHOR]

Biosynthesis of bisaryl preanthraquinone antibiotics by various microorganisms differs in monomeric subunits as well as their dimerization positions leading to different configurations. The present study relates to the production of rare bisaryl anthraquinone antibiotics by a new Streptomyces strain isolated from Shivalik region of NW Himalayas. In vitro anticancer and anti-migratory effects of Setomimycin (9,9′ bisanthraquinone antibiotic) was seen with a significant reduction in the expression of both MEK as well as ERK pathways in a dose dependent manner at 6.5 μM & 8 μM concentration in HCT-116 and 5.5 μM & 7 μM concentration in MCF-7 cells. In vivo studies in aggressive orthotopic mouse mammary carcinoma model (4T1) demonstrated about 76% reduction of primary tumor weight and 90.5% reduction in the tumor volume within two weeks. In vivo pharmacokinetics study of setomimycin revealed that it can be rapidly absorbed with an adequate plasma exposure and half-life which can be linked to its in vivo efficacy. [Display omitted] • Setomimycin, a rare bisaryl anthraquinones isolated from novel Streptomyces sp. strain from NW Himalayas. • An optima increase of par-4 was observed at 8 μM in HCT-116 cells and 7 μM in MCF-7 cells. • In-vivo studies in 4T1 mice model resulted in 90.5% reduction in the tumor volume within two weeks. • Setomimycin could absorbe rapidly (T max < 20 min) with a maximum plasma concentration level (C max >1 μM). [ABSTRACT FROM AUTHOR]

The IPCC in its Fourth Assessment Report (AR4) described the Himalayan Region as data-deficient in terms of climate monitoring. This is a serious impediment to global research initiatives and thus necessitates long-term ecological monitoring (LTEM) across the Himalaya. Being governed by low temperature conditions, the high-altitude regions in Himalaya are more responsive to changing environmental conditions and hence serve as better indicators. We identified few Protected Areas (PAs) and selected forest core area and ecotones along the temperate, sub-alpine, alpine and cold desert ecosystems in Himachal Pradesh to establish a network of permanent monitoring plots (PMPs). Land and vegetation cover map of three selected PAs has been prepared using Landsat TM satellite data. Among the 10 PMPs, the temperate and tree line forests in the GHNP were found to have the highest tree diversity with Taxus wallichiana showing good stand density and regeneration. The soil pH was found to be higher for cold desert and lower for tree line forests and alpine meadows. Soil total carbon and nitrogen contents ranged from 1.08% to 13.37% and 0.094% to 1.14% respectively. It was observed that the herbs diversity showed a positive trend with increasing soil carbon and nitrogen concentrations. Satellite remote sensing proves to be a useful tool in an LTEM study, including biodiversity assessment and climate change research in complex terrains such as the Himalaya. [ABSTRACT FROM AUTHOR]