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Magnetotelluric (MT) and audio-magnetotelluric (AMT) studies are sensitive to the geothermal fluids filling the faults and/or fracture zones of the geothermal system. In India, MT/AMT studies have been carried out in NW Himalayas, central, eastern, and western India. In other areas, detailed MT/AMT studies need to be expedited. This review paper presents the art of geothermal exploration in India by using MT/AMT techniques and identifies potential zones that can be exploited for power generation and direct application. Reservoir characteristics, carbon emissions reduction methods, and levelised cost factor are also discussed. [ABSTRACT FROM AUTHOR]

Long-term experiments are essential in understanding the ecological consequences of global land use and climate change. Further, it is well established that longterm data sets are prerequisites for effective management of forest resources and biodiversity conservation. In view of this, the present study attempts to contribute to major global long-term ecological monitoring (LTEM) networks and the status of LTEM studies in India with a special focus on Indian Himalayan Region. Over the last 40 years, around 103 countries from the America, Europe, Africa, Asia and Australia have been engaged in LTEM studies on various aspects of biodiversity, monitoring and predicting climate change impacts in a range of ecosystems, including the mountains. The temporal distribution of past studies on the subject shows a gradual increasing pattern (3 papers in 1992) with a peak during 2021 (105 papers). The established LTEM networks across the globe provide a significant empirical basis for understanding ecosystem structure and dynamics. Literature indicates plenty of permanent monitoring plots from India, mostly from southern India, and their significant contribution to ecosystem understanding. Himalayan regions are important sites for monitoring biological and socio-ecological responses to environmental perturbations, including climate change. LTEM studies are lacking in the IHR; only a few sites have been established, mostly in alpine ecosystems. This review identifies research gaps, opportunities with respect to LTEM studies, and the possibilities for strengthening long-term research and observation in India in general and the Himalaya in particular. [ABSTRACT FROM AUTHOR]

The term =sacred grove' is used to denote an area of vegetation that is afforded special protection on religious grounds. In India, where sacred groves are known by a wide repertoire of local names, such places may be found right from the Himalayas up to the far South. Sacred groves host veneration of natural phenomena or elements of landscape, but also ancestral, local, folk or tribal gods and Sanskritised deities; the use of their resources is strictly regulated. Research studies on sacred groves in India often consider them to be a legacy of archaic economic forms, possibly harking back to the stage of hunters-gatherers, and an expression of a religiosity dating back to a remote, non-Aryan, pre-Vedic antiquity. However, main sources for our knowledge of Indian antiquity, namely the literary sources, provide no direct record of voices of such archaic societies. Nonetheless, the same sources allow us to highlight some important aspects of the sacredness anciently ascribed to vegetation, forest, and specific places therein. The present paper proposes to focus on the Brahmanical hermit's distinct relationship with the forest and examine some aspects related to food. [ABSTRACT FROM AUTHOR]

Continental collision zones form at convergent plate boundaries after the negatively buoyant oceanic lithosphere subducts entirely into the Earth's mantle. Consequently, orogenesis commences, and the colliding continents are sutured together. During the collision, plate convergence and motion of the sutured boundary towards the overriding plate are manifest in its deformation, as is the case for the long-term (∼50 Ma) and nearly constant convergence rate at the India–Eurasia collisional zone that hosts the Himalaya. However, despite the long history of modelling subduction-collision systems, it remains unclear what drives this convergence, especially in models where subduction is driven solely by buoyancy forces. This paper presents dynamic self-consistent buoyancy-driven 2-D whole-mantle scale numerical models of subduction-and-collision processes to explore variations in density and rheological stratification of the colliding continent and overriding plate (OP) viscosity (a proxy for OP strength) that facilitate post-collisional convergence and collisional boundary migration. In models with a moderately buoyant indenting continent, the collisional boundary advance is comparatively low (0.1–0.6 cm yr–1), and convergence is driven by the dense continental lithospheric mantle that continues to subduct as it decouples from its deforming crust. Conversely, models with a highly buoyant indenting continent show sustained indentation at 0.5–1.5 cm yr–1 until the slab detaches. Furthermore, models with a weaker OP and lower backarc viscosity show an enhanced propensity for indentation by a positively buoyant continent. These models additionally highlight the role of whole mantle flow induced by the sinking of the detached slab in the lower mantle as it sustains slow convergence at an average rate of 0.36 cm yr–1 for ∼25 Myr after break-off as well as prevents the residual slab from educting. In previous buoyancy-driven partial mantle depth models such eduction does generally occur, given that free-sinking of the detached slab in the mantle is not modelled. Although these findings widen the understanding of the long-term convergence of indenting continents, the lower post-collisional advance rates (0.3–1.5 cm yr–1) compared to India's approximate 1000–2000 km of northward indentation during the last 50 Myr attest to the need for 3-D models. [ABSTRACT FROM AUTHOR]

Simple Summary: Drugs are used to treat cancer. Most drugs available in the market are chemosynthetic drugs and have side effects on the patient during and after the treatment, in addition to cancer itself. For instance, hair loss, loss of skin color and texture, loss of energy, nausea, infertility, etc. To overcome these side effects, naturally obtained drugs from medicinal plants are preferred. Our review paper aims to encourage the study of anticancer medicinal plants by giving detailed information on thirty-three medicinal plants and parts that constitute the phytochemicals responsible for the treatment of cancer. The development of plant-based drugs could be a game changer in treating cancer as well as boosting the immune system. Cancer is a serious and significantly progressive disease. Next to cardiovascular disease, cancer has become the most common cause of mortality in the entire world. Several factors, such as environmental factors, habitual activities, genetic factors, etc., are responsible for cancer. Many cancer patients seek alternative and/or complementary treatments because of the high death rate linked with cancer and the adverse side effects of chemotherapy and radiation therapy. Traditional medicine has a long history that begins with the hunt for botanicals to heal various diseases, including cancer. In the traditional medicinal system, several plants used to treat diseases have many bioactive compounds with curative capability, thereby also helping in disease prevention. Plants also significantly contributed to the modern pharmaceutical industry throughout the world. In the present review, we have listed 33 medicinal plants with active and significant anticancer activity, as well as their anticancer compounds. This article will provide a basic set of information for researchers interested in developing a safe and nontoxic active medicinal plant-based treatment for cancer. The research will give a scientific foundation for the traditional usage of these medicinal herbs to treat cancer. [ABSTRACT FROM AUTHOR]

A palynological assay of the studies carried out from the Western and the Eastern Himalaya (India) during the Late Pleistocene and Holocene is presented here. The Western Himalaya is affected by both the Indian Summer Monsoon (ISM) and Western Disturbances, whereas the Eastern Himalaya receives precipitation only from the ISM. During the Late Pleistocene (~77 ka), a cold and arid climate supported steppe vegetation in the Western Himalaya. In the Eastern Himalaya, around 66 ka, a cool and dry climate supported the savannah vegetation with few scattered trees of Pinus and Tsuga. A number of warm-moist fluctuations are also perceptible during the Late Pleistocene. The impacts of Last Glacial Maximum, Holocene Climatic Optimum, Medieval Warm Period and Little Ice Age are well discernible in the vegetation in both the regions. Within a broad similarity, the climate change and associated vegetation succession varied from region to region; as the palynological records are characterized by the evidences of prolonged humid phases in the eastern sector, whereas the arid events are better marked in the western part. The similarities and incompatibilities in the climate and vegetation between the Western and Eastern Himalaya during the Late Pleistocene and Holocene are discussed in the present paper. [ABSTRACT FROM AUTHOR]

Traditional knowledge has been used throughout the world including India as a practice of using local herbal drugs. Majority of the locals living in the district Uttarkashi of Uttarakhand state have poor connectivity and socio-economic status. These people are known to have indigenous experience about the medicinal plants of the area and use their age-old experiences and perceptions in the treatment and prevention of various ailments. Present paper documents the ethnobotanical information and conservation status of 82 medicinal herbs from the hilly district of Uttarakhand. Information gathered include, local name, plant parts used, mode of preparations, medium of administration, ailments cured along with distribution and conservation status. Majority of these plants were used for their roots and leaves. Most of them are herbs while trees and climbers were less frequently used. People living in remote areas have a vast treasure of knowledge, but they do not disclose it easily to outsiders. During surveys and interactions, it has been noticed that due to over exploitation, some medicinal herbs are at the verge of extinction which need to be conserved at the earliest. [ABSTRACT FROM AUTHOR]

A vast amount of knowledge and experience on coping with climatic variability and extreme weather events exists within local communities, and indigenous coping strategies are important elements of successful adaptation plans. Traditional knowledge can help to provide efficient, appropriate and time-tested ways of responding to climate change especially in far-flung communities. However, little is known about how traditional coping strategies translate into adaptation to long-term changes, and to what degree they prevent pro-active, transformational responses to climate change. This paper assesses the use of climate related information for communities in the Himalayan foothills of rural India, and reports on the barriers to adaptation planning and actions. Surveys have been carried out to analyze the current practices and the role of information in planning for climate change adaptation in the rural areas of the Nainital region of India located in Western Himalaya. Respondents perceive the local climate change, the intensity of change, and the negative impacts on the community and landscape. Decreases in water quantity and changes in precipitation patterns are among the major concerns for respondents, however, communities have begun to use traditional knowledge and historical climate information for developing strategies suitable to cope with impacts of climate change. Going forward, additional information is needed to match the high priority community needs with viable adaptation strategies. Lack of money, lack of access to information, and lack of awareness or understanding are considered the three largest hurdles besides low priority for adaptation, recognized by community members as barriers to adaptation planning and actions. Adaptation plans must be integrated into both top-down and bottom-up approaches to plan for enabling sustainable development and the efficient use of information for adaptation. Finally, traditional knowledge seems to be useful not only in contrasting climate change impacts, but also in recovering several ecosystem services that work all together for enanching the quality of life of villagers at local scale. [ABSTRACT FROM AUTHOR]

The Siwalik foreland deposit was earlier considered as freshwater continental megafan deposit, formed by southward flowing transverse drainages, analogous to modern Kosi-like megafans. However, this analogy remained incomplete due to lack of evidence of a regionally persistent axial stream system or marginal marine depositional system, like the Ganga-Brahmaputra River and Ganga Delta, as in the present-day foreland basin. In this paper, we report the abundant wave-generated structures and marine trace fossils from the Siwalik succession of the Tista valley and infer that they represent the deltaic part of the Neogene foreland basin. This interpretation provides the link between upland fluvial deposits of the western Himalaya and deep marine sediments of the Bengal Fan and is more consistent with available data from the Siwaliks of the eastern Himalaya. It also implies that a marine embayment existed in the eastern part of the Siwalik foreland basin. [ABSTRACT FROM AUTHOR]

The present paper deals with the morphological diversity of seedling establishment in different populations of Scaligeria stewartiana (Nasir) Nasir, inhabiting in North-West Himalayas. The seedling at different stages in the population of the species revealed marked variability. Seed treatments for germination resulted in understanding of seed dormancy and time required for the seedling establishment. The species develops variability in the genetic level that is transmitted and reflected in the form of morphology in order to adapt itself in the extremes of biotic and abiotic variables. Photographs of the seedling and data compiled in tables catch the specific stages of their seedling development after germination as well variability of the chromosomes. The initiation of tuber formation under the ground level in the soil and allocation of resources perform indispensable role in the life span as well as in paving the way for survival, conservation and distribution of the species. [ABSTRACT FROM AUTHOR]

In this paper, daily modulating behaviors of Indian summer monsoon rainfall (ISMR) has been evaluated over eight important sub-zones of India viz Northwest India (NWI); Northcentral India (NCI); West Peninsular India (WPI); Eastern Peninsular India (EPI); Southern Peninsular India (SoPI); Central India (CI), Northeast India (NEI) and Western Ghat (WG) using latest SA-CORDEX simulated climate data during 1981–2015. The climate extreme indices, standardized precipitation index (SPI) and empirical orthogonal function (EOF) have been utilized to uncover substantial regional spatial patterns and temporal variability of monsoon precipitation over India and its sub regions to understand the regional modulation of these events based on duration, frequency and severity. The comprehensive assessment of ISMR modulated characteristics (intensity, spell, and frequency) were showing significant decreasing trend over NEI and NCI which can be leading factors for demarcating major hotspots for land degradation, effective management and adaptation towards water resources and hazards related to the flood/drought events. India has received flood events (1983, 1988, 1994, 2005, 2011, 2013) and drought event (1982, 1987, 2002, 2004 and 2009) during 1981–2015, which have been verified with SA-CORDEX RCMs (RegCM4.7, COSMO & REMO2015) using SPI. The first mode of EOF(IMD), explained 17% of the total SPI variability on the interannual scale, shows anomalous large positive values concentrated over the western peninsular region and extending towards central India as well as the NWI region of India. On the other hand, high anomalous negative values dominated over the NEI and eastern parts of the Indo-Gangetic Plain. Therefore, this study underscores the importance to uncover the prevalent dynamics and climate change variability on changing trend variability of the precipitation indices, drought and flood characteristics. As moderate to severe drought variability portrays a diversity over regional scale viz northwest India, north central India, eastern ghat of the southern peninsular region and northeast India while the occurrence of moderate to severe flood are dominated towards Himalaya region (26°N-35°N; 70°E-80°E), western peninsular region and western ghat. • Modulating behavior of regionalized daily ISMR shows a significant decreasing trend over northeast and north-central India. • Moderate to severe drought portrays significant variability over regional scale viz. NWI, NCI, eastern ghat of SPI and NEI. • Occurrence of moderate to severe flood events are more dominated in the Himalaya region, WPI and WGs. • Critically regionalized hotspots susceptible to drought and flood have been demarcated. [ABSTRACT FROM AUTHOR]

The Matiali fan is a coarse-grained, small alluvial fan in the eastern Himalayan foothills. It co-exists side by side with the large Tista megafan and other Quaternary fluvial deposits, and has been affected by a number of young thrust faults. It is generally believed that tectonics is the main control in the deposition of these proximal fan–terrace systems. In this paper, geomorphologic and sedimentologic study of the Matiali fan and associated river terraces are combined with five OSL dates from these deposits to understand the succession of events and the forcing mechanism that shaped the geomorphology in the study area during late Quaternary time. Two aggradational terraces (T1 and T2; T2 > T1) occur within the river valleys incised on the Matiali fan. Three E–W scarps cross the fan surface, and they represent the steeper limb of the asymmetric fault-propagation folds formed over blind thrusts. These folds have deformed the fan (T3) and T2 terrace sediments, but the youngest T1 terrace deposits have remained undeformed. Sedimentological studies indicate continuous gradation from the coarsening-upwards mass-flow megagravel in the proximal part to the traction transported finer sheetflood gravels in the distal part, implying a continuous sedimentation history across the fan, uninterrupted by any evidence of syn-depositional tectonic movement. Poorly consolidated sandy gravels of the terraces indicate deposition through braided fluvial processes during a later period of sediment aggradation that filled up the incised river valleys. Previously published 14 C dates indicate that deposition of the Matiali fan started around 34 ka coinciding with a period of the intensified Indian summer monsoon of MIS-3. It is suggested that the fan was abandoned and river valleys incised during the LGM between 24 and 18 ka when the discharge decreased substantially. Increased rainfall and sediment supply, with their inherent fluctuations, during wetter periods of MIS-2 and MIS-1 since 12 ka probably resulted in the aggradation of T2 and T1 as shown by our OSL dates. OSL dates from the top of deformed T2 and base of undeformed T1 indicate that the Chalsa fold formed between ~ 11 and ~ 6 ka. Succession of geomorphic and deformational events reconstructed from this study and available age data indicate that the Matiali fan and terrace aggradation coincides with periods of increased monsoonal precipitation, whereas tectonic movements along blind thrusts of Chalsa and Matiali took place later, deforming the fan and older terrace deposits. The evidence unequivocally indicates, contrary to the prevalent notion of tectonic control of geomorphic features in the proximal mountain-front setting, that the deposition of the fan–terrace system was primarily controlled by the fluctuation of the Asian summer monsoon rather than Himalayan tectonics. [ABSTRACT FROM AUTHOR]

Forest fires due to pine needles in the northwestern Himalayas during summers are a very common phenomenon every year causing major harm to flora and fauna. They are a major contributor to climate change as forest fires destroy hectares of land covered by forest and emit greenhouse gases in the atmosphere. One possible solution to this problem is to generate energy from the bio residue of pine tree. This paper intends to identify, categorize and prioritize the major factors that hinders and are barriers to energy generation using pine needles in the state of Uttarakhand, India. This paper adopts a multi-criteria decision-making approach based on the technique of fuzzy Analytical Hierarchy Process. Sensitivity analysis is also used to test the robustness of this technique. The study finds that Legal and regulatory factors are the most critical and categorized as major influences of such renewable energy generation project, which includes government policy, project guidelines, financial support, technical support, and government clearances. The second barrier is economic which majorly includes cost factor associated with the development and sustenance of such energy generation projects. Technological and market related factors are next on the priority to energy generation using pine needles through limitations such as topography, hilly terrain, seasonal availability, supply chain, poor marketing. Human resource barriers stands at the fifth place and has less influence on such energy generation initiatives. This paper will help the policy makers to understand the priorities while solving energy generation issues to reduce forest fires and contribute to mitigate climate change. • To categorize the major factors negatively affecting energy generation using Pine needles. • To assess and prioritize these barriers. • To deliver managerial and practical implications for these barriers. • Legal and regulatory most critical barrier to pine needle based energy generation. • Lack of proper marketing has topmost global ranking as barrier. [ABSTRACT FROM AUTHOR]

Global climate change has numerous implications for members of mountain communities who feel the impacts in both physical and social dimensions. In the Western Himalayas of India, a majority of residents maintain a livelihood strategy that includes a combination of subsistence or small-scale agriculture, seasonal pastoral migration, male out-migration, and localized natural resource extraction. Particularly under conditions of heavy male outmigration, but throughout the region, mountain women play a key role in providing labor and knowledge related to the management of local natural resources, yet often lack authority in related political and economic decision-making processes. This gap has important implications for addressing the impacts of climate change: while warming temperatures, irregular patterns of precipitation and snowmelt, and changing biological systems present challenges to the viability of these traditional livelihood portfolios throughout the region, mountain women increasingly face new challenges in their roles as household managers that have not adequately been emphasized in larger scale planning for climate change adaptation and mitigation. These challenges are complex in nature, and are shaped not only by gender issues but also interacting factors such as class, caste, ethnicity, and age (among others). In this paper, we review the main arguments behind the discursive gender/climate change nexus, discuss the implications for gendered vulnerabilities and transformation of adaptive capacities in the region, and suggest ways that researchers and policymakers seeking to promote "climate justice" can benefit from the incorporation of gender-based perspectives and frameworks. [ABSTRACT FROM AUTHOR]

Dynamism of river bed morphology is continuous and an integrated process of mountain's natural outflow in Himalayan Foothill Rivers. In-stream seasonal sediment flux, bridge establishments, bridge scouring and railway-road construction have detrimental influence over the natural flow regime of the river thereby causing channel degradation in the piedmont zone of eastern Himalaya of India, specifically near the urban areas where river management strategies are very weak. Such extreme anthropogenic events have a distinctive influence in changing river bed morphology in the middle-lower part of river Chel in Darjeeling Himalayan piedmont zone of India. Huge sediment aggradation and transportation networks historically have affected River Chel and have caused channel avulsion which poses a serious threat to the physical and ecological environment of Chel. Aggradation and lifting of sediments from the river bed are fatal for the geomorphologic character of the river, though no studies have been undertaken yet, to analyse the situation quantitatively in this regard. This paper presents evidence that suggests the changing river bed morphology, the dynamic nature of the river, the poor health of the river which is principally the impact of the seasonal sediment flux and bridge construction and thus some methods of river restoration in the middle-lower part of the river have been explained. Agglomeration of sediment, flow bifurcation, the volume of seasonal water mass, bed elevation changes and scouring are a major dynamic disposition for change of river bed morphology. Point bar, sidebar, braided active channel, ripples, and rise in the bed elevation are rapid changes in upper to lower part of bridges that are examined in the present study. In the dry season (December to February), a huge amount of sediment lifting makes incommodious man-made holes and a number of emergent channels which principally control the formation of a new active channel in the next monsoon season. The avulsion of major intra-active channels and morphological changes of the river bed for the last 85 years have also been observed in this study. Unlabelled Image • This paper presents evidence that suggests that the changing river bed morphology, the dynamic nature of the river, the poor health of the river is principally the impact of the huge sediment aggradation and bridge construction and thus some methods of river restoration in the middle-lower part of river Chel. • Suspended sediment, aggradation and degradation, Scouring calculation for boulder agglomeration, Compare of satellite images and Topographical map for braided channel shifting are major methods for understanding of outcome results. • Agglomeration of sediment, flow bifurcation, volume of seasonal water mass, bed elevation change and scouring are major dynamic disposition for change of river bed morphology by bridge construction scouring. [ABSTRACT FROM AUTHOR]

The High Altitude GAmma-Ray (HAGAR) array is a wavefront sampling array of 7 telescopes, set-up at Hanle, at 4270mamsl, in the Ladakh region of the Himalayas (Northern India). It constitutes the first phase of the HImalayan Gamma-Ray Observatory (HIGRO) project. HAGAR is the first array of atmospheric Cherenkov telescopes established at a so high altitude, and was designed to reach a relatively low threshold (currently around 200 GeV) with quite a low mirror area (31m²). Regular source observations are running since September 2008. Estimation of the sensitivity of the experiment is undergoing using several hours of data from the direction of Crab nebula, the standard candle source of TeV gamma-ray astronomy, and from dark regions. Data were acquired using the On-source/Off-source tracking mode, and by comparing these sky regions the strength of the gamma-ray signal could be estimated. Gamma-ray events arrive close to telescope axis direction while the cosmic-ray background events arrive from the whole field of view. We discuss our analysis procedures for the estimate of arrival direction, estimate of gamma ray flux from Crab nebula, and the sensitivity of the HAGAR system, in this paper. [ABSTRACT FROM AUTHOR]

The northeast region of India is one of the world's most significant biodiversity hotspots. One of the richest bird areas in India, it is an important route for migratory birds and home to many endemic bird species. This paper describes a literature-based dataset of species occurrences of birds of northeast India. The occurrence records documented in the dataset are distributed across eleven provinces of India, viz.: Arunachal Pradesh, Assam, Bihar, Manipur, Meghalaya, Mizoram, Nagaland, Sikkim, Tripura, Uttar Pradesh and West Bengal. The geospatial scope of the dataset represents 24 to 29 degree North latitude and 78 to 94 degree East longitude, and it comprises over 2400 occurrence records. These records have been collated from scholarly literature published between1915 and 2008, especially from the Journal of the Bombay Natural History Society (JBNHS). The temporal scale of the dataset represents bird observations recorded between 1909 and 2007. The dataset has been developed by employing MS Excel. The key elements in the database are scientific name, taxonomic classification, temporal and geospatial details including geo-coordinate precision, data collector, basis of record and primary source of the data record. The temporal and geospatial quality of more than 50% of the data records has been enhanced retrospectively. Where possible, data records are annotated with geospatial coordinate precision to the nearest minute. This dataset is being constantly updated with the addition of new data records, and quality enhancement of documented occurrences. The dataset can be used in species distribution and niche modeling studies. It is planned to expand the scope of the dataset to collate bird species occurrences across the Indian peninsula. [ABSTRACT FROM AUTHOR]

Little statistical evidence exists on the effects of forest management regimes and wealth on forest access rates in South Asia. To determine the magnitude and significance of these effects, this paper analyzes a dataset of communities from Himachal Pradesh, India, with a fractional logit model. The investigation considers three specific forest management regimes including a regime under complete state control, traditional community regime and a co-management regime known as Joint Forest Management. Communities with higher incidence of land poverty have lower forest access rates for grazing and fodder extraction, whereas communities with a higher incidence of land-rich households have higher forest access rates for fodder extraction. Forest access rates for fuelwood collection are lower under traditional and co-management regimes. However, the interaction between land-poverty and co-management regime increases forest access rates for fodder collection and livestock grazing. [Copyright &y& Elsevier]

Abstract: In this paper, we created predictive models for assessing the susceptibility to shallow translational rocksliding and debris sliding in the Darjeeling Himalayas (India) by empirically selecting and weighting spatial predictors of landslides. We demonstrate a two-stage methodology: (1) quantifying associations of individual spatial factors with landslides of different types using bivariate analysis to select predictors; and (2) pairwise comparisons of the quantified associations using an analytical hierarchy process to assign predictor weights. We integrate the weighted spatial predictors through multi-class index overlay to derive predictive models of landslide susceptibility. The resultant model for shallow translational landsliding based on selected and weighted predictors outperforms those based on all weighted predictors or selected and unweighted predictors. Therefore, spatial factors with negative associations with landslides and unweighted predictors are ineffective in predictive modeling of landslide susceptibility. We also applied logistic regression to model landslide susceptibility, but some of the selected predictors are less realistic than those from our methodology, and our methodology gives better prediction rates. Although previous predictive models of landslide susceptibility indicate that multivariate analyses are superior to bivariate analyses, we demonstrate the benefit of the proposed methodology including bivariate analyses. [Copyright &y& Elsevier]

Abstract: In this paper, the Fry analysis was applied to study the spatial patterns (in terms of trends) of rockslides; proportion analysis was applied to study the spatial associations between rockslides and slope aspects; and distance distribution analysis was applied to study the spatial associations of rockslides with different sets of faults/fractures based on trends. In a study area in the Darjeeling district (India), the results of applications of these spatial analytical techniques support a proposition of mutual fault/fracture and slope controls on rocksliding. In different parts of the study area, deep-seated rockslides are associated with (a) NE-trending faults/fractures and SSE-facing slopes, (b) NW-trending faults/fractures and ENE-facing slopes, and (c) NNE-trending faults/fractures and SE- or ENE-facing slopes; whereas shallow translational rockslides are associated with (a) NNE-trending faults/fractures and SE-, NW-, WNW- or WSW-facing slopes, (b) WNW-trending faults/fractures and SW-facing slopes, (c) NNW-trending faults/fractures and ESE- or SW-facing slopes, and (d) NW-trending faults/fractures with SW-facing slopes. Creating and integrating spatial evidence layers representing mutual fault/fracture and slope controls on rocksliding can be achieved satisfactorily via application of evidential belief functions. A predictive map of rockslide susceptibility derived by using slope aspects, slope inclinations and proximity to the faults/fractures that are spatially associated with rockslides is superior to that derives by using slope aspects, slope inclinations and proximity to all faults/fractures. The proposed analytical methods are suitable for first-pass regional-scale assessment of rockslide susceptibility. [ABSTRACT FROM AUTHOR]

The objective of this paper is to estimate permanent displacements of Tehri dam due to an earthquake of magnitude M w = 8·5, the occurrence of which has a high probability in the region, and for an earthquake of magnitude M w = 7·0, for which the dam has been currently designed. A two-dimensional finite element analysis and five different semi-empirical and empirical methods, like, Seed and Makdisi’s method, Newmark’s double integration method, Jansen’s method, Swaisgood’s method and Bureau’s method have been utilized to study the probable dynamic behaviour of the dam and their results are compared to get a range of values within which, the permanent displacement of the dam, is estimated to lie. The present study shows that the predicted displacements due to an earthquake of magnitude Mw = 7·0 are significant but not enough to compromise the safety of the dam. However, the displacements predicted for an earthquake of magnitude Mw = 8·5 are quite high and might cause rupture of filter zones. The maximum deformations (755 cm for Mw = 8·5 and 43 cm for Mw = 7·0) are predicted by Seed and Makdisi’s method while the minimum deformations (14 cm for Mw = 8·5 and 2·5 cm for Mw = 7·0) are computed by Jansen’s method. [ABSTRACT FROM AUTHOR]

Abstract: Recognition and classification of landslides is a critical requirement in pre- and post-disaster hazard analysis. This has been primarily done through field mapping or manual image interpretation. However, image interpretation can also be done semi-automatically by creating a routine in object-based classification using the spectral, spatial and morphometric properties of landslides, and by incorporating expert knowledge. This is a difficult task since a fresh landslide has spectral properties that are nearly identical to those of other natural objects, such as river sand and rocky outcrops, and they also do not have unique shapes. This paper investigates the use of a combination of spectral, shape and contextual information to detect landslides. The algorithm is tested with a 5.8m multispectral data from Resourcesat-1 and a 10m digital terrain model generated from 2.5m Cartosat-1 imagery for an area in the rugged Himalayas in India. It uses objects derived from the segmentation of a multispectral image as classifying units for object-oriented analysis. Spectral information together with shape and morphometric characteristics was used initially to separate landslides from false positives. Objects recognised as landslides were subsequently classified based on material type and movement as debris slides, debris flows and rock slides, using adjacency and morphometric criteria. They were further classified for their failure mechanism using terrain curvature. The procedure was developed for a training catchment and then applied without further modification on an independent catchment. A total of five landslide types were detected by this method with 76.4% recognition and 69.1% classification accuracies. This method detects landslides relatively quickly, and hence has the potential to aid risk analysis, disaster management and decision making processes in the aftermath of an earthquake or an extreme rainfall event. [Copyright &y& Elsevier]

Abstract: This paper reports a study of the Tista megafan in the foothills of Darjeeling Himalaya. Spread over parts of India and Bangladesh, the megafan is bounded by the Mahananda River to its west and the Tista River to the east. The Atrai and Karatoya Rivers flow through its axial part. The megafan covers an area of ~18,000km2. Near its apex the surface slope is ~0.19°, that declines to 0.01° near the toe. The east–west transverse profile of the megafan is broadly upward convex, with gently sloping (~0.01°) flanks. Maximum width and the length of the megafan are about 145km and 166km respectively. The highest point near the megafan apex is ~150m above the Brahmaputra alluvial plain. The Tista River flanking the megafan has an average annual discharge of 609m3/s with highest average monthly discharge exceeding 2000m3/s during monsoon. Most of the other channels currently traversing the megafan are plains-fed, and compared to Tista and Mahananda Rivers these channels have lesser discharge, higher sinuosity, and decreased widths. A radiating network of abandoned channel belts can be identified in satellite images of the megafan. Each of these major paleochannels is associated with numerous crevasse channels in the distal part of the megafan, forming an intricate network of radial drainage on the megafan surface. Three distinct depositional lobes can be recognised on the Tista megafan. Each of the lobes is identified by a set of ancient and modern radial drainage systems. The lobe boundaries are marked by discordance in drainage network of adjacent lobes. The relative ages of the lobes, as tentatively determined from the drainage discordances, indicate that the megafan first built up the eastern lobe (lobe 1), then shifted to the west to form lobe 2, and finally switched again eastward giving rise to the smallest lobe located close to the mountain front (lobe 3). Although broadly upward convex in cross profiles, subtle reflections of multiple lobes are apparent in some of the cross profiles. Study of the old maps published between 1794 and 1945 reveals that some of the present-day plains-fed rivers, like the Tangon, the Atrai and the Karatoya, were directly connected to the Himalayan catchment basins prior to the late eighteenth century. Archaeological excavations along the banks of these rivers appear to support this paleodrainage configuration. Eight facies and five facies associations were recognised in the uppermost megafan sediments. Facies associations suggest deposition from high-energy sandy streams in the proximal area and deposition from mixed load, sinuous streams and flanking marsh or lake in the distal part of the lobes. Paleocurrent data are consistent with a southwestward spreading paleochannel pattern recognised within the studied part of the megafan. Multiple lobes typify megafans ocurring in different parts of the globe. The existence of the mutiple accretionary lobes in Tista megafan, its radial drainage pattern, its concave-upward longitudinal and convex-upward transverse profile shape make it morphologically comparable with other high-gradient alluvial fans observed in nature and those produced in the laboratory. These morphological features denote the similarities between the small, high-gradient alluvial fans and large, low-gradient megafans, and that in turn may be indicative of the commoness in certain controlling factors between these two depositional systems. [Copyright &y& Elsevier]

Abstract: This paper presents the detailed rainfall characteristics of 3 key areas located in the eastern monsoon India: the margin of Darjeeling Himalaya, the margin of Bhutanese Himalaya and the Cherrapunji region at the southern slope of Meghalaya Upland. All these areas are sensitive to changes but differ in annual rainfall totals (2000–4000 mm, 4000–6000 m and 6000–23,000 mm respectively) and in the frequency of extreme rainfalls. Therefore the response of geomorphic processes is different, also due to various human impact. In the Darjeeling Himalaya the thresholds may be passed 2–3 times in one century and the system may return to the former equilibrium. At the margin of western Bhutanese Himalaya in 1990s, the clustering of three events caused an acceleration in the transformation and formation of a new trend of evolution, especially in the piedmont zone. In the Cherrapunji of Meghalaya region in the natural conditions the effects of dozens of extreme rainfalls every year were checked by the dense vegetation cover. After deforestation and extensive land use the fertile soil was removed and either the exposed bedrock or armoured debris top layer protect the surface against degradation and facilitate only rapid overland flow. A new “sterile” system has been formed. [Copyright &y& Elsevier]