Implications of tree species–environment relationships for the responsiveness of Himalayan krummholz treelines to climate change

Climate warming is expected to advance treelines to higher elevations. However, empirical studies in diverse mountain ranges give evidence of both advancing alpine treelines as well as rather insignificant responses. In this context, we aim at investigating the sensitivity and responsiveness of the near-natural treeline ecotone in Rolwaling Himal, Nepal, to climate warming. We analysed population densities of tree species along the treeline ecotone from closed forest stands via the krummholz belt to alpine dwarf shrub heaths (3700-4200 m) at 50 plots in 2013 and 2014. We quantified species - environment relationships, i.e. the change of environmental conditions (e.g., nutrient and thermal deficits, plant interactions) across the ecotone by means of redundancy analyses, variation partitioning and distance-based Moran's eigenvector maps. In particular, we focus on explaining the high competitiveness of Rhododendron campanulatum forming a dense krummholz belt and on the implications for the responsiveness of Himalayan krummholz treelines to climate change. Results indicate that treeline trees in the ecotone show species-specific responses to the influence of environmental parameters, and that juvenile and adult tree responses are modulated by environmental constraints in differing intensity. Moreover, the species - environment relationships suggest that the investigated krummholz belt will largely prevent the upward migration of other tree species and thus constrain the future response of Himalayan krummholz treelines to climate warming.     

Statistical response of randomly excited nonlinear radial oscillations in polytropes

The effect of internal noise on the response characteristics of nonlinear radial pulsation in polytropic model has been investigated using the equivalent linearization technique. The model of the noise is taken to be δ-correlated with zero mean. Both non-stationary and stationary response characteristics have been computed for various nonlinearity parameters in different polytropes. This work is supported by UGC, New Delhi.     

Tracking IMF Fluctuations Nearby Sun Using Wavelet Analysis: Parker Solar Probe First Encounter Data

Geomagnetism and Aeronomy - The Parker Solar Probe (PSP) satellite was launched by NASA in 2018 to study the Sun’s environment from a closer distance than any spacecraft has ever reached...     

Identification of Groundwater Potential Zones using Remote Sensing and GIS of K-J Watershed,India

Groundwater potential zone mapping has become easier with the inputs from Remote Sensing (RS) & Geographical Information System (GIS) techniques. Various thematic maps like geology, geomorphology, drainage density, slope, landuse/landcover etc can be easily generated through RS & GIS. The present study is aimed at generating groundwater potential map of Koshalya-Jhajhara (K-J) watershed by using integrated approach of RS & GIS. Various thematic layers have been generated and assigned weightages and ranks. These layers have been integrated in GIS software for generating Groundwater Potential Zone (GPZ) map of K-J watershed. The area falls into five categories of groundwater potential zones i.e. very good, good, moderate, poor and very Poor depending on the likelihood of availability of ground water. On the basis of this study it is found that only 5.83 km² and 4.91 km² area is under very good and good category of groundwater availability respectively. An area of 24.48 km² is found under moderate category whereas dominant portion of K-J watershed i.e. 61.83 km² and 37.87 km² area falls under poor and very poor category of availability of groundwater respectively.     

Assessing coastal landscape vulnerability using geospatial techniques along Vizianagaram–Srikakulam coast of Andhra Pradesh,India

Vizianagaram–Srikakulam coastal shoreline consisting of beaches, mangrove swamps, tidal channel and mudflats is one of the vulnerable coasts in Andhra Pradesh, India. Five site-specific parameters, namely rate of geomorphology, coastal elevation, coastal slope, shoreline change and mean significant wave height, were chosen for constructing coastal vulnerability index and assessing coastal landscape vulnerability. The findings revealed a shift of 2.5 km in shoreline towards the land surface because of constant erosion and that of 1.82 km towards the sea due to accretion during 1997–2017. The rate of high erosion was found in zones IV and V, and high accretion was found in zones II and III. Coastal vulnerability index analysis revealed constant erosion along shoreline and sea level rise in the study area. Most of the coast in zone V has recorded very high vulnerability due to erosion, high slope, significant wave height and sea level rise. Erosion and accretion, significant wave height, sea level rise and slope are attributed to high vulnerability in zones III and IV. Zone II recorded moderate vulnerability. Relatively lower slope, mean sea wave height and sea level rise have made this zone moderately vulnerable. Very low vulnerability was found in zone I, and low vulnerability was recorded in zone II. Accretion, low slope and low sea level rise were found to be causative factors of lower vulnerability. Thus, zones III, IV and V should be accorded higher priorities for coastal management. The findings can be helpful in coastal land planning and management and preparing emergency plans of the coastal ecosystems.     

Expansion of a glacial lake,Tsho Chubda,Chamkhar Chu Basin,Hindukush Himalaya,Bhutan

Natural Hazards - A wide range of methods for detection of glacial lakes and their expansions using multi-temporal remote sensing images have been employed in the past. This paper presents a...     

Policy making for renewable energy in India: lessons from wind and solar power sectors

It is clear that developing countries will have to be part of the global mitigation effort to avoid ‘dangerous climate change’, and, indeed, many of them are already undertaking significant actions on multiple fronts to help address this problem, even if they have not yet taken on legally binding commitment under the United Nations Framework Convention on Climate Change (UNFCCC). Since the deployment of GHG-mitigating technologies is already a significant part of this effort and likely to be even more so in the future, drawing lessons from existing programmes can help accelerate and enhance the effectiveness of this deployment process. Accordingly, this article aims to examine the deployment of wind and solar power in India, paying specific attention to the role of public policy in incentivizing and facilitating this deployment, how these policies have evolved over time, what has shaped this evolution, and what the learning has been over this period. Through this analysis, the intention is to draw out key lessons from India's experience with deployment policies and programmes in these two sectors and highlight the issues that will need to be given particular consideration in the design of future domestic policies and international cooperation programmes to enhance the move towards climate-compatible development in India. Many of these lessons should also be relevant for other developing countries that are attempting to balance their climate and developmental priorities through the deployment of renewable energy technologies.     

Mitigation of earthquake-induced damage of breakwater by geogrid-reinforced foundation

A strong earthquake often precedes a tsunami, and a breakwater may settle during the earthquake. Such seismic subsidence of the breakwater may reduce its ability to block the tsunami, and the tsunami may easily enter coastal areas by overflowing it. This study deals with the instability of a breakwater due to an earthquake. In addition, to protect a breakwater from damage caused by an earthquake, a new concept of using geogrid for reinforcing the foundation of a breakwater is introduced. To determine the behavior of unreinforced foundation and to evaluate the effectiveness of the proposed reinforced foundation under different earthquake loadings, a series of shaking table tests were performed. It was observed that the earthquake generated excess pore water pressures and deformations of foundation ground were main reasons of failure of the breakwater. The reinforced foundation was found effective to reduce the earthquake-induced damage of the breakwater, and finally it makes the breakwater resilient against earthquake-induced forces. Numerical simulations were also performed to elucidate the mechanism of reinforcement–breakwater–soil–water system under different earthquake loadings.     

地热：被遗忘的重要清洁能源

如果我们能够将美国地下约3km深度的地热全部提取出来,将会满足美国未来3万年的能量需求（根据目前的使用量）。将所有的能源取尽是不可能的,这涉及到技术和经济层面的问题,但是只要提取这些地热资源的5％就能够生产出满足2．6亿美国人需要的用电量。美国国家能源部可再生能源实验室（NREL,     

Mathematical modelling of Visakhapatnam Port utilizing the porous and non-porous breakwaters with finite depth green function

Ocean Dynamics - A mathematical model based on the three-dimensional (3-D) boundary element method (BEM), including porous and non-porous breakwaters, is developed to determine the wave trapping...