|
Endotoxin associated with ambient PM (particulate matter) has been linked to adverse respiratory symptoms, but there have been few studies of ambient endotoxin and its association with co-pollutants and inflammation
. Our aim was to measure endotoxin associated with ambient PM10 (particulate matter with aerodynamic diameter<10µm) in summer 2016 at four locations in Chitwan, Nepal, and investigate its association with meteorology, co-pollutants, and inflammatory activity. PM10 concentrations were recorded and filter paper samples were collected using E-samplers; PM1, PM2.5, black carbon (BC), methane (CH4), and carbon monoxide (CO) were also measured. The Limulus amebocyte lysate (LAL) assay was used for endotoxin quantification and the nuclear factor kappa B (NF?B) activation assay to assess inflammatory activity. The mean concentration of PM10 at the different locations ranged from 136 to 189µg/m3, and of endotoxin from 0.29 to 0.53EU/m3. Pollutant presence was positively correlated with endotoxin. Apart from relative humidity, meteorological variations had no significant impact on endotoxin concentration. NF-?B activity was negatively correlated with endotoxin concentration. To the best of our knowledge, this study provides the first measurements of ambient endotoxin associated with PM10 in Nepal. Endotoxin and co-pollutants were positively associated indicating a similar source. Endotoxin was negatively correlated with inflammatory activity as a result of a time-limited forest fire event during the sampling period. Studies of co-pollutants suggested that the higher levels of endotoxin related to biomass burning were accompanied by increased levels of anti-inflammatory agents, which suppressed the endotoxin inflammatory effect
Read More
|
|
The Indian subcontinent has suffered some of the greatest earthquakes in the world
. The earthquakes of the late nineteenth and early twentieth centuries triggered a number of early advances in science and engineering related to earthquakes that are discussed here. These include the development of early codes and earthquake-resistant housing after the 1935 Quetta earthquake in Baluchistan, and strengthening techniques implemented after the 1941 Andaman Islands earthquake, discovered by the author in remote islands of India. Activities in the late 1950s to institutionalize earthquake engineering in the country are also discussed. Despite these early developments towards seismic safety, moderate earthquakes in India continue to cause thousands of deaths, indicating the poor seismic resilience of the built environment. The Bhuj earthquake of 2001 highlighted a striking disregard for structural design principles and quality of construction. This earthquake was the first instance of an earthquake causing collapses of modern multi-storey buildings in India, and it triggered unprecedented awareness amongst professionals, academics and the general public. The earthquake led to the further development of the National Information Centre of Earthquake Engineering and the establishment of a comprehensive 4-year National Programme on Earthquake Engineering Education that was carried out by the seven Indian Institutes of Technology and the Indian Institute of Science. Earthquake engineering is a highly context-specific discipline and there are many engineering problems where appropriate solutions need to be found locally. Confined masonry construction is one such building typology that the author has been championing for the subcontinent. Development of the student hostels and staff and faculty housing on the new 400-acre campus of the Indian Institute of Technology Gandhinagar has provided an opportunity to adopt this construction typology on a large scale, and is addressed in the monograph. The vulnerability of the building stock in India is also evident from the occasional news reports of collapses of buildings under construction or during rains (without any earthquake shaking). Given India’s aspirations to be counted as one of the world’s prosperous countries, there is a great urgency to address the safety of our built environment. There is a need: to create a more professional environment for safe construction, including a system for code enforcement and building inspection; for competence-based licensing of civil and structural engineers; for training and education of all stakeholders in the construction chain; to build a research and development culture for seismic safety; to encourage champions of seismic safety; to effectively use windows of opportunity provided by damaging earthquakes; to focus on new construction as opposed to retrofitting existing buildings; and to frame the problem in the broader context of overall building safety rather than the specific context of earthquakes. Sustained long-term efforts are required to address this multi-faceted complex problem of great importance to the future development of India. While the context of this paper is India, many of the observations may be valid and useful for other earthquake-prone countries
Read More
|
|
Summary Glaciers are crucial in many countries where meltwater from glaciers is an important source of water for drinking water supply, irrigation, hydropower generation and the ecological system
. Glaciers are also important indicators of climate change. They have been significantly altered due to the global warming and have subsequently affected the regional hydrological regime. However, few models are able to parameterise the dynamics of the glacier system and consequent runoff processes in glacier fed basins with desirable performance measures. To narrow this gap, we have developed an integrated approach by coupling a hydrological model (HBV) and a glacier retreat model ( Δ h -parameterisation) and tested this approach in three basins with different glacier coverage and subject to different climate and hydrologic regimes. Results show that the coupled model is able to give satisfactory estimations of runoff and glacier mass balance in the Nigardsbreen basin where the measured data are available to verify the results. In addition, the model can provide maps of snowpack distribution and estimate runoff components from glaciers
Read More
|
|
The hydrology of Himalayan basins is not well understood due to the complexities in the climate and geography, and the scarcity of data
. The objective of this study is to quantitatively assess the contribution of various components of runoff in the Himalayan basins. To achieve this goal, the Hydrologiska Byråns Vattenbalansavdelning (HBV) model was used to simulate the runoff and its components on two Himalayan basins, the Beas River basin, India and the Wang Chhu basin, Bhutan. Four components of runoff from glacier melting, snow melting on glacier, snow melting outside glacier, and rainfall were identified by the HBV model. The simulation results show that the HBV model can give a fair estimation of the runoff of these two catchments and the effects of glacier and snow are largely dependent on the catchment characteristics and the glaciated area. For the Wang Chhu basin, the largest contributor to runoff is rainfall, whereas melting of snow and glacier is dominant in the Beas River basin. This research will not only contribute to the improved understanding of the impacts of climate change on the hydrological response in the Himalaya area, but will also provide guidanc
Read More
|
|
|
|
Advocacy Strategies and Approaches: A Training of Trainers Manual on Advocacy Strategies for Community-based Organisations in the Hindu Kush-Himalayas, and its companion Resource Manual, were developed for potential trainers of community-based organisations (CBOs) in the HKH region
. The manuals are intended to provide useful guides for conducting regional and local-level training on advocacy applicable to a variety of mountain development issues and themes. The Resource Manual provides trainers with more in-depth material on subjects discussed in the training manual. The manuals attempt to provide clarity on the concept of advocacy and to help equip CBOs and their networks with tools, strategies, and techniques that will help them assist mountain people to advocate for appropriate strategies to address their social, economic, gender, and other issues, and to articulate their needs and perspectives to governments, policy makers, and development organisations. The manuals are also likely to appeal to development practitioners and others interested in promoting people-centred, sustainable mountain development
Read More
|
|
A conceptual snowmelt model, which accounts for both the snowmelt and rainfall runoff was developed and applied for daily streamflow simulation for the Satluj River basin located in the western Himalayan region
. The model, designed primarily for mountainous basins, conceptualizes the basin as a number of elevation zones depending upon the topographic relief. The basic inputs to the model are temperature, precipitation and snow-covered area. The snowmelt is computed using the degree-day approach and rain induced melting was also considered. The model was calibrated using a data set of three years (1985/86–1987/88) and model parameters were optimized. Using these optimized parameters, simulations of daily streamflow were made for a period of six years (1988/89–1990/91 and 1996/97– 1998/99). The model performed well for both calibration and simulation periods. The model was also used to estimate the contribution from the snowmelt and rainfall to the seasonal and annual flows
Read More
|
|
Assessment of soil erosion, sediment transport and deposition of sediment in the reservoirs, irrigation and hydropower systems are considered essential for the land and water management
. The magnitude of sediment transported by rivers has become a serious concern for the water resources planning. In the present study, an assessment of sediment yield has been made for the Satluj River, which flows through the western Himalayan region. Two approaches have been used for the assessment of sediment yield (i) relationship between suspended sediment load and discharge and (ii) empirical relationship. The first approach was used for Satluj Basin up to Suni (52 983 km2), Kasol (53 768 km2) and also for the intermediate basin between Kasol and Suni (785 km2). The sediment-discharge relationship was developed using daily data for a period of three years (1991–1993) for different basins and was applied for each basin for the years 1994 and 1996 for estimation of sediment yield. The second approach, which gives annual sediment yield, has been used for a small intermediate basin only because of data availability constraints. For estimation of the sediment yield using the empirical relationship, various geographical parameters such as land use, topographical etc. were generated using Geographic Information System (GIS) technique. The annual sediment yield for the intermediate basin was estimated for three years and compared with observed values. The trend of difference between computed and observed sediment yield suggested an effect of physical features of mountainous basins. The available empirical relationship was, therefore, revised by incorporating a basin parameter in the equation. This basin parameter represented an integrated effect of slope and spatial distribution of rainfall in the mountainous basin. Using the revised empirical relationship, the sediment yield was estimated for two independent years and a good correlation was found between computed and observed sediment yield
Read More
|
|
Abstract Streamflow in the Himalayan rivers is generated from rainfall, snow and ice
. The distribution of runoff produced from these sources is such that the streamflow may be observed in these rivers throughout the year, i.e. they are perennial in nature. Snow and glacier melt runoff contributes substantially to the annual flows of these rivers and its estimation is required for the planning, development and management of the water resources of this region. The average contribution of snow and glacier melt runoff in the annual flows of the Satluj River at Bhakra Dam has been determined. Keeping in view the availability of data for the study basin, a water balance approach was used and a water budget period of 10 years (October 1986-September 1996) was considered for the analysis. The rainfall input to the study basin over the water budget period was computed from isohyets using rainfall data of 10 stations located at different elevations in the basin. The total volume of flow for the same period was comp..
Read More
|
|
|