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We reconstructed summer (June–September) minimum temperature for eastern Nepal over the past 288 years (1733–2020 CE), using a total tree-ring width chronology of Himalayan Larch (Larix griffithiana (Lindl. and Gord.)) from Kanchanjunga Conservation Area (KCA). This study is the first minimum temperature reconstruction for the eastern Himalaya region of Nepal. We examined the response of the Larix ring-width chronology to different climate variables including precipitation, and minimum, maximum and mean temperatures. Of all climatic variables, minimum temperature has the strongest correlation with tree-ring chronology. This response revealed that the growth of the L. griffithiana is limited by temperature-induced physiological behaviors during summer season. The reconstruction shows fluctuating warm and cool periods during the entire period and captures warming during recent decades. This increasing warming trend appears to be unprecedented in the context of the past 288 years. We observed short (2.5 years) and multidecadal (35, 43, 71 and 100 years) cyclicity, which suggests possible atmospheric teleconnection with the broader circulation system of Atlantic Multidecadal Oscillation (AMO). This possible teleconnection is further revealed in spatial field correlation and also supported by temporal comparison of the reconstruction with instrumental- and proxy-based AMO records. [ABSTRACT FROM AUTHOR]

Urban forest ecosystems, the structure, and functions therein are subjected to anthropogenic disturbances. Native and sensitive species from those forests might be lost due to such disturbances. At the same time, supplemented anthropogenic resources might create opportunities for exotic and invasive species. Although invasive species are considered one of the major threats to the urban biodiversity and ecosystems, the research on invasion dynamics in the Himalayas has primarily focused on the impacts of invasion on forest structure and productivity. This study aims to understand the influence of forest structure and anthropogenic factors in invasion success that are poorly covered in the existing literature. We selected 11 urban forest patches for the study considering the presence-absence of selected invasive species and structural attributes. We used Principal Component Analysis (PCA) to reduce co-linearity in the covariates and generalized linear mixed effects model (GLMM) to identify the factors affecting invasion success. We found that forest structural attributes, namely, tree diameter, height and canopy cover, and anthropogenic disturbances regulate invasion success in urban forests. This implies that maintaining urban forest structural attributes, especially the stands with large-sized trees, is essential to control invasion in the context of urbanization. [ABSTRACT FROM AUTHOR]

Long term stability of an underground cavern is significant for construction engineers. For structures constructed in the geologically active regions of the Himalayas, continuous monitoring is required to ward off the sustained threats due to seismic activities and associated local geological hazards. Underground powerhouse of Tapovan Vishnugad Hydropower Power Project (TVHPP), Chamoli, Uttarakhand is one such powerhouse that encountered various types of rockmass failures both during and post construction. The project area is located about 2.0 km north of the Main Central Thrust (MCT) and the rockmass cavern has numerous joints, shear and seam zones and fractures. This pose threat to the long term stability of this underground powerhouse cavern. To analyse the rockmass stability of the powerhouse, real time microseismic monitoring system was installed in this underground cavern. Spatio-temporal variation of the recorded seismic events has been analysed for microseismic events distribution in terms of seismic energy, displacement, cumulative apparent volume and various other contours led to the identification of potentially hazardous zones in the underground rockmass structure. [ABSTRACT FROM AUTHOR]

Changes in the global temperature and precipitation regime have been significantly driving species responses, notably in sensitive areas such as the Himalayas. By conducting a study at two high altitude (3200–4100 m) valleys (Langtang and Tsum) situated in the central part of the Nepal Himalayas, we presented tree-ring width site chronologies for two Larix species (Larix griffithii and L. himalaica) for the first time. The longest chronology spans from 1771 to 2015 AD and showed a recent decline in the growth of Larix species in both sites, controlled mainly by drought. Tree growth showed a negative response to temperature and a positive response to precipitation, indicating that moisture stress is limiting the growth of the species. Based on the Larix ring width chronology statistics and climate response results, these species have good potential for past climate reconstruction such as temperature, rainfall or drought indices. Also, the study revealed that the Himalayan endemic Larix species investigated are promising for tree-ring based multi-aspect environmental change studies in the future. [ABSTRACT FROM AUTHOR]

Landslides are the most common hazards which modify the surface morphology of the orogenic belts. Structural conditions and nature of slope forming material play a vital role in the development of surface morphology. The paper highlights the influence of structure on slope morphology and consequent instability pattern in Sukhidang-Ladhiya section in Eastern Kumaun Himalaya. Rocks of lesser Himalayan sequences, Siwalik Group and veneer of Quaternary deposits occur in the area. The area is punctuated by many landslides of various dimensions affecting all the lithological units present; however, study is based on three major landslides occurring along the Main Boundary Thrust (MBT) and Himalayan Frontal Thrust (HFT) zone. Structural data shows that thrusts environment has manifested in crushing and shearing of rocks, which play an important role in landslide proneness along with the rainfall intensity. Evidences of active tectonics such as triangular facets (flatirons), tilting river terraces and active landslides zones have been noticed in the study area. Limited data on temporal details of landslide morphology (perimeter and area) from remote sensing and topographical sheets indicate that perimeters and area of active scars of landslides in the area are gradually expanding, probably associated with tectonic movements in proximal areas of thrusts. [ABSTRACT FROM AUTHOR]

Communities in and around protected areas are exposed to a higher level of human-wildlife interactions. The conservation practice with persistently adverse local livelihood outcomes can potentially aggravate such interactions leading to conflict. In our study, we examined how perceptions of HWC have formed in a protected area of the Trans-Himalayas whose conservation program collides with a centuries-long tradition of transhumance pastoralism. To examine determinants of depredation and how conflict perception has developed there, along with the socioeconomic and ecological interactions underlying those trends, we collected data using household surveys, key informant interviews, and focus group discussions. We employed Poisson-logit maximum-likelihood hurdle, binary logit, and multinomial ordered logit regressions in order to explore the determinants of annual livestock depredation, predator attacks on the shed, and household-level perceptions of HWC, respectively. Depredation and encounters with wildlife were the principal causes of perceived HWC, and depredation caused an average household-level loss of US $422.5, up to 23.28% of annual income in some households. Predators' attacks on high-quality sheds were relatively infrequent but more common in areas with perceived habitat degradation. Social customs, pastoral practices, and the present compensation mechanism were identified as being antithetical to conflict reduction and sustainable pastureland management. Further analysis revealed that a diversity of livelihoods, however, lowered conflict perception formation. The identified socio-ecological factors will continue to increase depredation, exacerbate perceived HWC, and degrade pastureland unless local conservation authorities take appropriate remedial measures. • Human wildlife conflict is serious and multifaceted. • Depredation causes serious impact on local livelihoods in conservation areas. • Shed attack by carnivores is related to predator diversity, perceived habitat loss, and herd size. • Economic loss by depredation and direct encounters with predators are key determinants of HWC perception. • Pastureland degradation, complex compensation mechanism, and socio-economic settings complicate the conservation efforts. [ABSTRACT FROM AUTHOR]

The Himalayan ecosystem has global significance for supporting unique and rich ecological and socio-cultural diversity as well as a range of ecosystem services important for the very survival of human beings. However, constant anthropogenic pressure, unsustainable developmental practices and climate change led to the transformation of irrational land-use practices that have seriously compromised the ecosystem productivity and livelihood of the mountain communities. Considering the above, integrated land use planning, effective land use policy and legislation is a key element to address unsustainable land-use practices in the Himalayan ecosystem. Realising the increasing trend of degradation of natural resources and associated livelihood challenges for rural communities, a comprehensive scientific framework was developed for improving the functionality of marginal degraded land. A total of twelve tree species used for a variety of purposes prioritised by local communities based on ecological, social and economic value were selected for plantation on marginal degraded land belonging to the village community. Significant improvement in survival rate, growth, and circumference of planted tree species was observed across the sites after ten years of the plantation. The plantation activities enhanced the net productivity of degraded landscape while increasing characteristics of soil leading to increment in water percolation, improve soil moisture and decreased runoff. Total biomass accumulated by tree species planted in three selected sites within the period significantly contributed to carbon sequestration thus reducing the adverse impact of changing climate. The provisioning services in the form of fuel, fodder, and grasses obtained from developed landscapes reduced the drudgery and workload of marginal communities. The study advocates interdisciplinary knowledge production, enrich social learning among stakeholders, improved understanding of current and future challenges associated with land-use practices and relevant policy implications for sustainable land management in the region. [Display omitted] • Growing bioenergy plantation on degraded land rejuvenates multiple ecosystems services. • We developed a wider framework for successful implementation of restoration programme. • Long term ecological and economic attributes of the developed models was assessed. • The tree crops planted on degraded land significantly enhanced the provision of ecosystem services. • The study advocates interdisciplinary knowledge production and relevant policy implications. [ABSTRACT FROM AUTHOR]