Search Results (694)

The evolution of Jurassic carbonates is globally significant for understanding the depositional framework, diagenetic phases and sedimentary characteristics of shallow marine shelf deposits. For this purpose, two outcrop sections of the Jurassic carbonates with a road distance of 121 km in the Trans Indus Ranges, NW Himalayas, were included in this study. Geological fieldwork was conducted for sedimentological data, and representative samples were collected for microfacies analysis and diagenetic evolution complemented by carbon and oxygen isotope analysis. Results show that eight microfacies were identified in both sections where mudstone microfacies was only present in the Chichali section, whereas wackestone and packstone facies widely existed in both sections. The diagenetic evolution interpreted that dolomitization and stylolization were pronounced in the Paniala section, while micritization and calcite cementation were prevalent in the Chichali section. The interpreted depositional setting implies the wide range from supratidal to outer ramp shallow marine for the Chichali section, suggesting a wide range and relatively deeper environment, alongside merely intertidal to middle ramp settings for Paniala section. Diagenetic evolution suggests marine to meteoric influence in the Chichali section, while burial and uplift phases were dominant in the Paniala section. The diagenetic events were also validated by the isotopic analysis, where most of the samples with values up to −4‰ VPDB δ¹⁸O, corresponding to a carbon isotope range of up to +4‰, were interpreted as the burial phase of diagenesis; meanwhile, a few samples with −2 δ¹³C and −7‰ VPDB δ¹⁸O isotope signatures were marked as meteoric influx in the Paniala section. This study indicates the diversity of the depositional environment and diagenetic heterogeneity by integration of thin sections using isotope data, which are quite applicable to shallow marine carbonates. Full article

Alpine lakes located in high-altitude mountainous regions act as vital sentinels of environmental change. Remote-sensing-based identification of these lakes is crucial for understanding their response to climate variations and for assessing associated disaster risks. However, the complex terrain and weather conditions in these areas pose significant challenges to accurate detection. This paper proposes a method that leverages the high precision of deep learning for small lake and lake boundary extraction combined with deep learning to eliminate noise and errors in the identification results. Using Sentinel-2 data, we accurately identified and delineated alpine lakes in the eastern Himalayas. A total of 2123 lakes were detected, with an average lake area of 0.035 km². Notably, 76% of these lakes had areas smaller than 0.01 km². The slope data is crucial for the lake classification model in eliminating shadow noise. The accuracy of the proposed lake classification model reached 97.7%. In the identification of small alpine lakes, the recognition rate of this method was 96.4%, significantly surpassing that of traditional deep learning approaches. Additionally, this method effectively eliminated most shadow noise present in water body detection results obtained through machine learning techniques. Full article

Background/Objectives: Roxadustat is an oral hypoxia-inducible factor prolyl hydroxylase inhibitor approved to treat anemia of chronic kidney disease (CKD). The efficacy and safety of roxadustat compared with parenteral erythropoiesis-stimulating agents (ESAs) were evaluated in patients with anemia of CKD receiving peritoneal dialysis (PD). Methods: This analysis pooled data from four phase 3, multicenter, randomized, open-label, active-comparator studies (PYRENEES, SIERRAS, HIMALAYAS, ROCKIES). The primary endpoints evaluated were hemoglobin change from baseline (CFB) to Weeks 28–36 without rescue therapy and hemoglobin CFB to Weeks 28–52 regardless of rescue therapy use. Safety data were reported. Results: This analysis included 422 patients (215 roxadustat, 207 ESA). Hemoglobin CFB to Weeks 28–36 without rescue therapy and hemoglobin CFB to Weeks 28–52 regardless of rescue therapy achieved non-inferiority for roxadustat vs. ESAs. The mean weekly dose of roxadustat was maintained over time (Weeks 1–4, 3.86 mg/kg/week; Weeks 101–104, 3.27 mg/kg/week), whereas the mean weekly ESA dose increased by 24% (Weeks 1–4, 115.70 IU/kg/week; Weeks 101–104, 143.40 IU/kg/week). Fewer patients treated with roxadustat received intravenous iron supplementation and rescue therapy, and patients treated with an ESA required blood transfusions sooner. Roxadustat-treated patients experienced a greater decrease in low-density lipoprotein cholesterol levels relative to baseline vs. ESA-treated patients. Treatment-emergent adverse events were similar in both treatment groups. Major adverse cardiovascular event (MACE), MACE plus unstable angina or congestive heart failure, and all-cause mortality hazard ratios were <1; the lower limit of the 95% CIs was <0.6, and the upper limit was >1.3. Conclusions: Roxadustat was non-inferior to ESAs in correcting and maintaining hemoglobin levels, with stable dosing and a comparable safety profile, in anemic patients receiving PD. Full article

The Sikkim region of the Eastern Himalayas is highly susceptible to Glacial Lake Outburst Floods (GLOFs), a risk that has increased significantly due to rapid glacial retreat driven by climate change in recent years. This study presents a comprehensive evaluation of GLOF susceptibility in Sikkim, employing Analytic Hierarchy Process (AHP) and Fuzzy Analytic Hierarchy Process (FAHP) models. Key factors influencing GLOF vulnerability, including lake volume, seismic activity, precipitation, slope, and proximity to rivers, were quantified to develop AHP and FAHP based susceptibility maps. These maps were validated using Receiver Operating Characteristic (ROC) curves, with the AHP method achieving an Area Under the Curve (AUC) of 0.92 and the FAHP method scoring 0.88, indicating high predictive accuracy for both models. A comparison of the two approaches revealed distinct characteristics, with FAHP providing more granular insights into moderate-risk zones, while AHP offered stronger predictive capability for high-risk areas. Our results indicated that the expansion of glacial lakes, particularly over the past three decades, has heightened the potential for GLOFs, highlighting the urgent need for continuous monitoring and adaptive risk mitigation strategies in the region. This study, in addition to enhancing our understanding of GLOF risks in Sikkim, also provides a robust framework for assessing and managing these risks in other glacial regions worldwide. Full article

Constraining the collision timing of India and Asia requires reliable information from the coeval geological record along the ~2400 km long collisional margin. This study provides insights into the India–Asia collision at the westernmost margin of the Indian Plate using combined U-Pb geochronological data and sandstone petrography. The study area is situated in the vicinity of Fort Munro, Pakistan, along the western margin of the Indian Plate, and consists of the Paleocene Dunghan Formation and Eocene Ghazij Formation. The U-Pb ages of detrital zircons from the Dunghan Formation are mainly clustered between ~453 and 1100 Ma with a second minor cluster between ~1600 and 2600 Ma. These ages suggest that the major source contributing to the Dunghan Formation was likely derived from basement rocks and the cover sequence exposed mainly in Tethyan Himalaya (TH), Lesser Himalaya (LH), and Higher Himalayan (HH). Petrographic results suggest that the quartz-rich samples from the Dunghan Formation are mineralogically mature and have likely experienced log-distance transportation, which is possible in the case of an already established and well-developed river system delivering the sediments from the Craton Interior provenance. Samples of the overlying Ghazij Formation show a major detrital zircon age clustered at ~272–600 Ma in the lower part of the formation, comparable to the TH. In the middle part, the major cluster is at ~400–1100 Ma, and a minor cluster at ~1600–2600 Ma similar to the age patterns of TH, LH, and HH. However, in the uppermost part of the Ghazij Formation, ages of <100 Ma are recorded along with 110–166 Ma, ~400–1100 Ma, and ~1600–2600 Ma clusters. The <100 Ma ages were mainly attributed to the northern source, which was the Kohistan-Ladakh arc (KLA). The ~110–166 Ma ages are possibly associated with the TH volcanic rocks, ophiolitic source, and Karakoram block (KB). The Paleozoic to Archean-aged zircons in the Ghazij Formation represent an Indian source. This contrasting provenance shift from India to Asia is also reflected in the sandstone petrography, where the sample KZ-09 is plotted in a dissected arc field. By combining the U-Pb ages of the detrital zircons with sandstone petrography, we attribute this provenance change to the Asia–India collision that caused the provenance shift from the southern (Indian Craton) provenance to the northern (KLA and KB) provenance. In view of the upper age limit of the Ghazij Formation, we suggest the onset of Asian–Indian collision along its western part occurred at ca. 50–48 Ma, which is younger than the collision ages reported from central and northwestern segments of the Indian plate margin with 70–59 Ma and 56 Ma, respectively. Full article

The need to focus on traditional crops for food security has been realized across the globe. ‘Bhat’ is an indigenous soybean variety from the Indian Himalayan Region that has been neglected in recent times due to changing agricultural choices. The present study was conducted on 52 indigenous soybean accessions collected from different villages of Uttarakhand, a hilly state in Northern India, to determine the concentrations of various macro- and microelements in the crop. The analysis used the HHXRF (handheld X-ray fluorescence) spectroscopic technique and atomic absorption spectroscopy (AAS). The findings reveal that the ‘bhat’ is an extremely nutrient-rich crop with calcium being the most significant macronutrient (highest concentration of 27,300 ppm), followed by phosphorus, potassium, and sulphur found in the bhat seeds. The study suggests that samples from Pauri Garhwal (Gwad Khirsu, Bironkhal, Sripur), Tehri (PratapNagar, Singoli), Chamoli (Paini, and Agastyamuni) villages were rich in all the major macronutrients. Among the micronutrients, silicon was found to be the most dominant with the highest concentration of 1920 ppm. This was followed by the dominance of iron, zinc, and manganese in descending order of abundance. Tipri, Chandola Rai Goonth, Chopdiun, and Paini villages were found to have the highest concentrations of microelements. The statistical data analysis confirms that seed samples from different regions are significantly similar in terms of nutrient concentrations, except for Si and Fe, thereby indicating that ‘bhat’ from any of the villages is equally good for consumption. However, seed samples from certain regions were found to be contaminated with heavy metals, indicating soil pollution, which demands attention towards current agricultural practices. The findings show that the crop is an exceptional source of essential and quasi-essential elements and should be promoted to benefit the hill populations. Full article

Soil erosion and subsequent sedimentation pose significant challenges in the Sikkim Himalayas. In this study, we conducted an assessment of the impact of rainfall-induced soil erosion and sediment loss in South Sikkim, which falls within the Teesta Basin, employing Revised Universal Soil Loss Equation (RUSLE) and Sediment Yield Index (SYI) models. Leveraging mean annual precipitation data, a detailed soil map, geomorphological landforms, Digital Elevation Models (DEMs), and LANDSAT 8 OLI data were used to prepare the factorial maps of South Sikkim. The results of the RUSLE and SYI models revealed annual soil loss >200 t ha⁻¹ yr⁻¹, whereas mean values were estimated to be 93.42 t ha⁻¹ yr⁻¹ and 70.3 t ha⁻¹ yr⁻¹, respectively. Interestingly, both models displayed similar degrees of soil loss in corresponding regions under the various severity classes. Notably, low-severity erosion <50 t ha⁻¹ yr⁻¹ was predominantly observed in the valley sides in low-elevation zones, while areas with severe erosion rates >200 t ha⁻¹ yr⁻¹were concentrated in the upper reaches, characterized by steep slopes. These findings underscore the strong correlation between erosion rates and topography, which makes the region highly vulnerable to erosion. The prioritization of such regions and potential conservation methods need to be adopted to protect such precious natural resources in mountainous regions. Full article

Owing to the taxonomic incongruence between the morphological features and genetic relationships of the sinica group of macaques (genus Macaca), the taxonomy of this macaque group has remained inconclusive. We aimed to resolve the taxonomic quandary and improve our understanding of the historical biogeography of the group by including macaque DNA samples from previously unsampled areas in the Himalayas. We sequenced and analyzed three mitochondrial DNA loci [cytochrome b (CYTB), cytochrome oxidase subunit 1 (COI) and D-loop; 2898 bp] for sequence polymorphism, phylogenetics, species delimitation, and ancestral area reconstruction. We confirmed the occurrence of Arunachal macaque (Macaca munzala) on the southern slopes of the Eastern Himalayas in the Xizang Zizhiqu (Tibet Autonomous Region) of China. The results revealed that the sinica group of macaques is a parapatric species group composed of seven distinct species. Phylogenetic and species delimitation analyses revealed that the two previously considered subspecies of Assamese macaques (the eastern subspecies M. assamensis assamensis and the western subspecies M. a. pelops) are two distinct species. The eastern Assamese macaque is a sister species to the Tibetan macaque, whereas the western Assamese macaque and Arunachal macaque are the closest genetic sister species. The sinica group of macaques underwent five vicariance and seven dispersal radiations in the past, which mainly coincided with the Quaternary climatic oscillations between the late Pliocene and the late Pleistocene. By integrating our phylogenetic and ancestral area reconstruction results with findings from previous paleontological and molecular studies, we propose a robust hypothesis about the phylogeography of the sinica group of macaques. Full article

The Ramganga River basin, comprising three rivers, the Dhela, Dhandi, and Ramganga, plays a vital role in groundwater recharge, sustaining numerous industries, urban areas, and rural communities reliant on these rivers for daily activities. The study’s primary purpose was to analyze the groundwater quality in the context of potability, irrigation, and health risks to the local inhabitants of the Ramganga River basin. In 2021–2022, 52 samples (26 × 2) were collected from 13 locations in two different seasons, i.e., pre-monsoon and post-monsoon, and 20 physico-chemical and heavy metal and metalloids were analyzed using the standard protocols. The result shows that heavy metal and metalloids and metalloid concentrations of Zn (0.309–1.787 and 0.613–1.633); Fe (0.290–0.965 and 0.253–1.720), Cd (0.001–0.002 and 0.001–0.002); As (0.001–0.002 and 0.001–0.002), Cr (0.009–0.027 and 0.011–0.029), and Pb (−0.001–0.010 and 0.00–0.010) values in mg/L are present in both seasons. The groundwater quality index (GWQI), heavy metal pollution Index (HPI), and heavy metal evaluation index (HEI) were used to assess the water quality and metal pollution in the basin area. As per GWQI values, water quality lies from excellent water quality (41.639 and 43.091) to good water quality (56.326 and 53.902); as per HPI values, it shows good (29.51 and 30.03) to poor quality (60.26 and 59.75) and HEI values show the low-level contamination (1.03–2.57 and 1.13–3.37) of heavy metal and metalloids in both seasons. According to the potential health risk assessment, infants show low risk in pre-monsoon and low risk to medium post-monsoon, while children and adults show low risk to high risk in both seasons. From the health risk perspective, it shows that children and adults have more concerns about non-carcinogenic effects, so adequate remedial measures and treatment are required to avoid the groundwater quality of the Ramganga River basin. Full article

The origin of Oligocene sediments in the Bengal Basin and associated tectonic setting remain poorly understood. This study investigates the framework mineralogy and major element geochemistry of the Barail Group sandstones from the Sylhet Trough within the Bengal Basin to clarify the provenance and tectonic history of the Oligocene. Modal analysis (Q₈₃F₇L₁₀) and geochemical data support a classification of sublitharenite to subarkose, some with Fe enrichment. The heavy mineral assemblage is dominated by opaque minerals, followed by ultrastable minerals with zircon > tourmaline > rutile. The sub-angular to sub-rounded sand grains with a compositionally moderate mature nature suggest that the sediments were deposited close to the source area. The mineralogical and geochemical provenance discrimination diagram suggests contributions from felsic igneous, sedimentary/metasedimentary, and low-grade metamorphic sources, with detritus derived from the Indian craton and proto-Himalaya region. Data suggest moderate to intense chemical weathering, indicative of low relief and a sub-humid to humid climate in the source area. The tectonic analyses indicate that the Bengal Basin transitioned from a predominantly passive margin to an active tectonic margin setting during the Oligocene. Full article

Albedo is a primary driver of the glacier surface energy balance and consequent melting. As glacier albedo decreases, it further accelerates glacier melting. Over the past 20 years, glaciers on the Tibetan Plateau have experienced significant melting. However, our understanding of the variations in glacier albedo and its driving factors in this region remains limited. This study used MOD10A1 data to examine the average characteristics and variations in glacier albedo on the Tibetan Plateau from 2001 to 2022; the MOD10A1 snow cover product, developed at the National Snow and Ice Data Center, was employed to analyze spatiotemporal variations in surface albedo. The results indicate that the albedo values of glaciers on the Tibetan Plateau predominantly range between 0.50 and 0.60, with distinctly higher albedo in spring and winter, and lower albedo in summer and autumn. Glacier albedo on the Tibetan Plateau decreased at an average linear regression rate of 0.06 × 10⁻² yr⁻¹ over the past two decades, with the fastest declines occurring in autumn at an average rate of 0.18 × 10⁻² yr⁻¹, contributing to the prolongation of the melting period. Furthermore, significant variations in albedo change rates with altitude were found near the snowline, which is attributed to the transformation of the snow and ice surface. The primary factors affecting glacier albedo on the Tibetan Plateau are temperature and snowfall, whereas in the Himalayas, black carbon and dust primarily influence glacier albedo. Our findings reveal a clear decrease in glacier albedo on the Tibetan Plateau and demonstrate that seasonal and spatial variations in albedo and temperature are the most important driving factors. These insights provide valuable information for further investigation into surface albedo and glacier melt. Full article

Frankliniella occidentalis, commonly known as the western flower thrips (WFT), is one of the world’s most significant cosmopolitan pests. This pest infests many ornamental species, including Alstroemeria, leading to substantial economic losses. F. occidentalis damages flowers, transmits viruses, and causes the rejection of shipments for exports. Farmers have observed variations in the occurrence of F. occidentalis among different Alstroemeria cultivars. It is hypothesized that differences in flower color and odor among cultivars may influence the host-choice behavior of this insect, potentially explaining the observed variations in incidence and damage in the field. To test this hypothesis, we analyzed one year’s worth of sampling data for the occurrence of the WFT complex in a commercial Alstroemeria greenhouse crop. This analysis identified cultivars with high and low thrips incidences. The ‘Himalaya’ and ‘Whistler’ cultivars exhibited the highest incidence, while the ‘Shakira’ and ‘Nora’ cultivars showed the lowest incidence values. To investigate the potential role of host odors in these field incidence differences, we conducted behavioral tests (choice, non-choice, and repellency) using glass boxes where visual stimuli were blocked. These tests confirmed a differential attraction response of thrips to the flowers of Alstroemeria cultivars, although all cultivars were viable options for WFT choice. Preferences under laboratory conditions differed from the incidence observed in the greenhouse, ruling out a repellency effect of some cultivars on insects. This study provides evidence that differential emissions from Alstroemeria flowers can influence host selection by WFT, a phenomenon that warrants further in-depth exploration in future studies. Full article

The Hindu Kush Himalaya (HKH) is one of the most flood-prone regions in the world, yet heavy cloud cover and limited in situ observations have hampered efforts to monitor the impact of heavy rainfall, flooding, and inundation during severe weather events. This paper introduces HydroSAR, a Sentinel-1 SAR-based hazard monitoring service which was co-developed with in-region partners to provide year-round, low-latency weather hazard information across the HKH. This paper describes the end user-focused concept and overall design of the HydroSAR service. It introduces the main processing algorithms behind HydroSAR’s broad product portfolio, which includes qualitative visual layers as well as quantitative products measuring the surface water extent and water depth. We summarize the cloud-based implementation of the developed service, which provides the capability to scale automatically with the event size. A performance assessment of our quantitative algorithms is described, demonstrating the capabilities to map the flood extent and water depth with an accuracy of >90% and <1 m, respectively. An application of the HydroSAR service to the 2023 South Asia monsoon seasons showed that monsoon floods peaked near 6 August 2023 and covered 11.6% of Bangladesh in water. At the peak of the flood season, nearly 13.5% of Bangladesh’s agriculture areas were affected. Full article

A well-designed tree-based culture provides multiple benefits, aiding in achieving sustainable development goals (SDGs), especially SDG1 (no poverty), SDG2 (zero hunger), SDG13 (climate action), and SDG15 (life on land). A split-plot field experiment near Solan, Himachal Pradesh, tested the following Grewia optiva tree spacings as main plots: S₁ 10 m × 1 m, S₂ 10 m × 2 m, S₃ 10 m × 3 m, and sole cropping (S₀—Open) of pea (Pisum sativum L.). Pea cultivation included the following six fertilizer treatments as subplots: control (no application), farmyard manure (FYM), vermicompost (VC), Jeevamrut, FYM + VC, and the recommended dose of fertilizers (RDFs), each replicated three times. The results indicated that the leaves, branches, total biomass, carbon density, and carbon sequestration rate of G. optiva alleys at 10 m × 1 m were greater than those at the other spacings. However, peas intercropped at 10 m × 3 m produced the highest yield (5.72 t ha⁻¹). Compared with monocropping, G. optiva-based agroforestry significantly improved soil properties. Among fertilizers, FYM had the highest yield (6.04 t ha⁻¹) and improved soil health. The most lucrative practice was the use of peas under a 10 m × 1 m spacing with FYM, with economic gains of 2046.1 USD ha⁻¹. This study suggests integrating pea intercropping with G. optiva at broader spacing (10 m × 3 m) and using FYM for optimal carbon sequestration, soil health, and economic returns, and this approach is recommended for the region’s agroecosystems. Full article

Climate change has severely impacted many species, causing rapid declines or extinctions within their essential ecological niches. This deterioration is expected to worsen, particularly in remote high-altitude regions like the Himalayas, which are home to diverse flora and fauna, including many mountainous ungulates. Unfortunately, many of these species lack adaptive strategies to cope with novel climatic conditions. The Red Goral (Naemorhedus baileyi) is a cliff-dwelling species classified as “Vulnerable” by the IUCN due to its small population and restricted range extent. This species has the most restricted range of all goral species, residing in the temperate mountains of northeastern India, northern Myanmar, and China. Given its restricted range and small population, this species is highly threatened by climate change and habitat disruptions, making habitat mapping and modeling crucial for effective conservation. This study employs an ensemble approach (BRT, GLM, MARS, and MaxEnt) in species distribution modeling to assess the distribution, habitat suitability, and connectivity of this species, addressing critical gaps in its understanding. The findings reveal deeply concerning trends, as the model identified only 21,363 km² (13.01%) of the total IUCN extent as suitable habitat under current conditions. This limited extent is alarming, as it leaves the species with very little refuge to thrive. Furthermore, this situation is compounded by the fact that only around 22.29% of this identified suitable habitat falls within protected areas (PAs), further constraining the species’ ability to survive in a protected landscape. The future projections paint even degraded scenarios, with a predicted decline of over 34% and excessive fragmentation in suitable habitat extent. In addition, the present study identifies precipitation seasonality and elevation as the primary contributing predictors to the distribution of this species. Furthermore, the study identifies nine designated transboundary PAs within the IUCN extent of the Red Goral and the connectivity among them to highlight the crucial role in supporting the species’ survival over time. Moreover, the Dibang Wildlife Sanctuary (DWLS) and Hkakaborazi National Park are revealed as the PAs with the largest extent of suitable habitat in the present scenario. Furthermore, the highest mean connectivity was found between DWLS and Mehao Wildlife Sanctuary (0.0583), while the lowest connectivity was observed between Kamlang Wildlife Sanctuary and Namdapha National Park (0.0172). The study also suggests strategic management planning that is a vital foundation for future research and conservation initiatives, aiming to ensure the long-term survival of the species in its natural habitat. Full article