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1.
Heliyon ; 10(10): e31139, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38813230

RESUMO

Nepal is one of the pioneers of hydropower development among Asian countries. The plethora of fast-flowing rivers provides immense potential for hydropower generation. However, Nepal still lacks a clear blueprint for the overall development and management of this sector. This paper aims to review the evolution of hydropower development, future prospects and roadblocks to hydropower development. With the growing energy demands projected to reach as high as 41,264.82 Gigawatt hours (GWh) in 2030 and 115,294.4 GWh in 2040 under different scenarios, this paper highlights the huge prospects the sector holds. It also proposes a focus on storage-type hydropower plants and concepts of energy banking to address the incipient condition of seasonal energy mismatch in the country, which has developed a condition of energy shortage during the winter and energy surplus during the monsoon. Moreover, projected changes in hydro-climatic extremes under the climate change scenarios is likely to affect water availability and subsequently the energy production in the majority of hydropower projects. Thus, this review can serve as a guideline to help understand the current scenario and make rational decisions and policies for the future management of the hydropower sector of the country.

2.
Agric Water Manag ; 283: 108287, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37265577

RESUMO

Climate variability and insufficient irrigation are primary constraints to stable and higher agricultural productivity and food security in Nepal. Agriculture is the largest global freshwater user, and integration of surface- and ground-water use is frequently presented as an strategy for increasing efficiency as well as climate change adaptation. However, conjunctive management (CM) planning often ignores demand-side requirements and a broader set of sustainable development considerations, including ecosystem health and economics of different development strategies. While there is generic understanding of conjunctive use, detailed technical knowhow to realize the CM is lacking in Nepal. This article presents a holistic framework through literature reviews, stakeholders consultations and expert interviews for assessing CM and implementation prospects from a systems-level perspective. We demonstrate the framework through a case study in Western Nepal, where climatic variability and a lack of irrigation are key impediments to increased agricultural productivity and sustainable development. Results show that knowledge of water resources availability is good and that of water demand low in the Western Terai. Additional and coordinated investments are required to improve knowledge gaps as well as access to irrigation. There is therefore a need to assess water resources availability, water access, use and productivity, to fill the knowledge gaps in order to pave pathways for CM. This paper also discusses some strategies to translate prospects of conjunctive management into implementation.

3.
Environ Res ; 215(Pt 1): 114104, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36057332

RESUMO

Climate change alters the river flow regimes causing significant changes in the structure and function of an aquatic ecosystem, ultimately affecting river health. This study applied a customized framework consisting of 1-index, 4-components, 6-indicators, and 43-metrics, to assess river health for two seasons and future periods, in the Marshyangdi Watershed, Nepal. Hydrological, water quality, biological and physical conditions were assessed using simulated results from a hydrological model, physiochemical analysis of water samples, macroinvertebrates assemblages analysis, and physical habitat condition assessment, respectively. Climate change impact on river health was assessed based on projected climate (precipitation and temperature) based on regional climate models under representative concentration pathways (RCP) 4.5 and 8.5 scenarios until the mid-century. Results showed moderate river health condition in both the seasons and it's deterioration for future scenarios and periods. It reveals the need to formulate appropriate measures for the conservation of the river health.


Assuntos
Mudança Climática , Rios , Ecossistema , Hidrologia , Nepal , Rios/química
4.
Environ Res ; 212(Pt D): 113434, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35618008

RESUMO

An understanding of water sufficiency provides a basis for informed-planning, development and management of water resources. This study assessed spatio-temporal distribution in water sufficiency in the Extended East Rapti watershed in Nepal. The "Palika" (local government unit) is considered as a spatial-scale and seasons and future periods as temporal-scale. The water sufficiency was evaluated based on water sufficiency ratio (WSR) and water stress index (WSI). A hydrological model was developed to simulate water availability. An ensemble of multiple Regional Climate Models was used for assessing climate change impacts. Results showed water sufficiency by mid-century is projected to decrease; WSR by 40% and WSI by 61%. Despite projected decrease in water sufficiency, annually available water resources are projected as sufficient for the demands until the mid-century, however, seasonal variability and scarcity in future is projected in most Palikas. Such results are useful for water security planning in the Palikas.


Assuntos
Mudança Climática , Rios , Hidrologia , Nepal , Recursos Hídricos
5.
Environ Res ; 183: 109149, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32000001

RESUMO

Groundwater resources of Kathmandu Valley in Nepal are under immense pressure from multiple stresses, including climate change. Due to over-extraction, groundwater resources are depleting, leading to social, environmental and economic problems. Climate change might add additional pressure by altering groundwater recharge rates and availability of groundwater. Mapping groundwater resilience to climate change can aid in understanding the dynamics of groundwater systems, facilitating the development of strategies for sustainable groundwater management. Therefore, this study aims to analyse the impact of climate change on groundwater resources and mapping the groundwater resiliency of Kathmandu Valley under different climate change scenarios. The future climate projected using the climate data of RCM's namely ACCESS-CSIRO-CCAM, CNRM-CM5-CSIRO-CCAM and MPI-ESM-LR-CSIRO-CCAM for three future periods: near future (2010-2039), mid future (2040-2069) and far future (2070-2099) under RCP 4.5 and RCP 8.5 scenarios were bias corrected and fed into the Soil and Water Assessment Tool (SWAT), a hydrological model, to estimate future groundwater recharge. The results showed a decrease in groundwater recharge in future ranging from 3.3 to 50.7 mm/yr under RCP 4.5 and 19-102.1 mm/yr under RCP 8.5 scenario. The GMS-MODFLOW model was employed to estimate the future groundwater level of Kathmandu Valley. The model revealed that the groundwater level is expected to decrease in future. Based on the results, a groundwater resiliency map of Kathmandu Valley was developed. The results suggest that groundwater in the northern and southern area of the valley are highly resilient to climate change compared to the central area. The results will be very useful in the formulation and implementation of adaptation strategies to offset the negative impacts of climate change on the groundwater resources of Kathmandu Valley.


Assuntos
Mudança Climática , Água Subterrânea , Monitoramento Ambiental , Hidrologia , Nepal
6.
Sci Total Environ ; 650(Pt 1): 365-383, 2019 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-30199682

RESUMO

Chamelia (catchment area = 1603 km2), a tributary of Mahakali, is a snow-fed watershed in Western Nepal. The watershed has 14 hydropower projects at various stages of development. This study simulated the current and future hydrological system of Chamelia using the Soil and Water Assessment Tool (SWAT). The model was calibrated for 2001-2007; validated for 2008-2013; and then applied to assess streamflow response to projected future climate scenarios. Multi-site calibration ensures that the model is capable of reproducing hydrological heterogeneity within the watershed. Current water balance above the Q120 hydrological station in the forms of precipitation, actual evapotranspiration (AET), and net water yield are 2469 mm, 381 mm and 1946 mm, respectively. Outputs of five Regional Climate Models (RCMs) under two representative concentration pathways (RCPs) for three future periods were considered for assessing climate change impacts. An ensemble of bias-corrected RCM projections showed that maximum temperature under RCP4.5 (RCP8.5) scenario for near-, mid-, and far-futures is projected to increase from the baseline by 0.9 °C (1.1 °C), 1.4 °C (2.1 °C), and 1.6 °C (3.4 °C), respectively. Minimum temperature for the same scenarios and future periods are projected to increase by 0.9 °C (1.2 °C), 1.6 °C (2.5 °C), and 2.0 °C (3.9 °C), respectively. Average annual precipitation under RCP4.5 (RCP8.5) scenario for near-, mid-, and far-futures are projected to increase by 10% (11%), 10% (15%), and 13% (15%), respectively. Based on the five RCMs considered, there is a high consensus for increase in temperature but higher uncertainty with respect to precipitations. Under these projected changes, average annual streamflow was simulated to increase gradually from the near to far future under both RCPs; for instance, by 8.2% in near-, 12.2% in mid-, and 15.0% in far-future under RCP4.5 scenarios. The results are useful for planning water infrastructure projects, in Chamelia and throughout the Mahakali basin, to ensure long-term sustainability under climate change.

7.
Sci Total Environ ; 612: 853-875, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-28886538

RESUMO

Impacts of climate change on water resources, especially groundwater, can no longer be hidden. These impacts are further exacerbated under the integrated influence of climate variability, climate change and anthropogenic activities. The degree of impact varies according to geographical location and other factors leading systems and regions towards different levels of vulnerability. In the recent past, several attempts have been made in various regions across the globe to quantify the impacts and consequences of climate and non-climate factors in terms of vulnerability to groundwater resources. Firstly, this paper provides a structured review of the available literature, aiming to critically analyse and highlight the limitations and knowledge gaps involved in vulnerability (of groundwater to climate change) assessment methodologies. The effects of indicator choice and the importance of including composite indicators are then emphasised. A new integrated approach for the assessment of groundwater vulnerability to climate change is proposed to successfully address those limitations. This review concludes that the choice of indicator has a significant role in defining the reliability of computed results. The effect of an individual indicator is also apparent but the consideration of a combination (variety) of indicators may give more realistic results. Therefore, in future, depending upon the local conditions and scale of the study, indicators from various groups should be chosen. Furthermore, there are various assumptions involved in previous methodologies, which limit their scope by introducing uncertainty in the calculated results. These limitations can be overcome by implementing the proposed approach.

8.
Sci Total Environ ; 575: 779-790, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27693144

RESUMO

This study aimed at evaluating three index-overlay methods of vulnerability assessment (i.e., DRASTIC, GOD, and SI) for estimating risk to pollution of shallow groundwater aquifer in the Kathmandu Valley, Nepal. The Groundwater Risk Assessment Model (GRAM) model was used to compute the risk to groundwater pollution. Results showed that DRASTIC and SI methods are comparable for vulnerability assessment as both methods delineate around 80% of the groundwater basin area under high vulnerable zone. From the perspective of risk to pollution results, DRASTIC and GOD methods are comparable. Nevertheless, all the three methods estimate that at least 60% of the groundwater basin is under moderate risk to NO3-N pollution, which goes up to 75% if DRASTIC or GOD-based vulnerabilities are considered as exposure pathways. Finally, based on strength and significance of correlation between the estimated risk and observed NO3-N concentrations, it was found that SI method is a better-suited one to assess the vulnerability and risk to groundwater pollution in the study area. Findings from this study are useful to design strategies and actions aimed to prevent nitrate pollution in groundwater of Kathmandu Valley in Nepal.

10.
Sci Total Environ ; 556: 23-35, 2016 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-26971207

RESUMO

Groundwater vulnerability and risk assessment is a useful tool for groundwater pollution prevention and control. In this study, GIS based DRASTIC model have been used to assess intrinsic aquifer vulnerability to pollution whereas Groundwater Risk Assessment Model (GRAM) was used to assess the risk to groundwater pollution in the groundwater basin of Kathmandu Valley. Seven hydrogeological factors were used in DRASTIC model to produce DRASTIC Index (DI) map which represent intrinsic groundwater vulnerability to pollution of the area. The seven hydrogeological factors used were depth to water, net recharge, aquifer media, soil media, topography, impact of vadose zone, and hydraulic conductivity of aquifer. GIS based GRAM was used to produce likelihood of release of hazards, likelihood of detection of hazards, consequence of hazards and residual risk of groundwater contamination in terms of nitrate in the groundwater basin. It was found that more than 50% of the groundwater basin area in the valley is susceptible to groundwater pollution and these areas are mostly in Northern groundwater district Low and very low vulnerable areas account for only 13% and are located in Central and Southern groundwater districts. However after taking into account the barriers to groundwater pollution and likelihood of hazards release and detection, it was observed that most areas i.e. about 87% of the groundwater basin are at moderate residual risk to groundwater pollution. The resultant groundwater vulnerability and risk map provides a basis for policy makers and planner's ability to use information effectively for decision making at protecting the groundwater from pollutants.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Água Subterrânea/química , Poluição da Água/estatística & dados numéricos , Abastecimento de Água/estatística & dados numéricos , Agricultura/estatística & dados numéricos , Monitoramento Ambiental , Sistemas de Informação Geográfica , Humanos , Nepal , Medição de Risco
11.
OMICS ; 19(6): 329-31, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26415138

RESUMO

Proteomics is at the epicenter of post-genomics biotechnologies that are currently driving the next generation system science. Moreover, proteomics is a truly global science. The 6(th) Annual Meeting of Proteomics Society, India (PSI) and International Conference on "Proteomics from Discovery to Function" held from December 7-9, 2014, was a transformative endeavor for global proteomics, bringing together the luminaries in the field of proteomics for the very first time in India. This meeting report presents the lessons learned and the highlights of this international scientific conference that was comprised of nine thematic sessions, pre- and post-conference workshops, and an opportunity to cultivate enduring collaborations for proteomics science to benefit both India and global society. The conference had an unforgettable impression on the participants: for the first time, India hosted past and present President and Council members from the Human Proteome Organization (HUPO), along with eminent scientists and young scholars from India and abroad in the field of proteomics at such a large scale, a major highlight of this international event. In all, the PSI 2014 was a milestone conference that has firmly poised the Indian life sciences community as a leading contributor to post-genomics life sciences, thus cultivating crucial trans-generational capacity and inspiration by recognizing the emerging scholars and omics systems scientists who can think and conduct science from cell to society.


Assuntos
Proteômica , Genômica , Índia , Proteoma/genética
12.
Environ Manage ; 48(5): 1044-59, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21915763

RESUMO

To assess the vulnerability of water resources in the Bagmati River Basin in Nepal, this paper adopts an indicator-based approach wherein vulnerability is expressed as a function of water stress and adaptive capacity. Water stress encompasses indicators of water resources variation, scarcity, and exploitation and water pollution, whereas adaptive capacity covers indicators of natural, physical, human resource, and economic capacities. Based on the evaluation of eleven indicators, which were aggregated into eight vulnerability parameters, an increasingly stressful situation and lack of adaptive capacity became evident. Considerable spatial variation in indicator values suggests differential policy options. While the northern parts need attention to reduce pollution loading and conserve vegetation cover, the southern parts need improvements in physical capacity, i.e. water infrastructures. The comprehensive and easily interpretable findings of the study are expected to help decision makers reach sound solutions to reduce freshwater resources vulnerability in the Bagmati River Basin, Nepal. With its inherent flexibility, the approach has demonstrated its potential for application in different times and areas for monitoring and comparison purposes.


Assuntos
Conservação dos Recursos Naturais , Monitoramento Ambiental , Água Doce/análise , Rios , Poluentes da Água/análise , Abastecimento de Água/análise , Animais , Humanos , Nepal , Medição de Risco/métodos , Abastecimento de Água/normas
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