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Stuart Orr Jamie Pittock Ashok Chapagain David Dumaresq 《Global Environmental Change》2012,22(4):925-932
Proposed dam construction in the Lower Mekong Basin will considerably reduce fish catch and place heightened demands on the resources necessary to replace lost protein and calories. Additional land and water required to replace lost fish protein with livestock products are modelled using land and water footprint methods. Two main scenarios cover projections of these increased demands and enable the specific impact from the main stem dam proposals to be considered in the context of basin-wide hydropower development. Scenario 1 models 11 main stem dams and estimates a 4–7% increase overall in water use for food production, with much higher estimations for countries entirely within the Basin: Cambodia (29–64%) and Laos (12–24%). Land increases run to a 13–27% increase. In scenario 2, covering another 77 dams planned in the Basin by 2030 and reservoir fisheries, projections are much higher: 6–17% for water, and 19–63% for land. These are first estimates of impacts of dam development on fisheries and will be strongly mediated by cultural and economic factors. The results suggest that basic food security is potentially at a high risk of disruption and therefore basin stakeholders should be fully engaged in strategies to offset these impacts. 相似文献
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Evaluation of groundwater environment of Kathmandu Valley 总被引：1，自引：1，他引：0
Vishnu Prasad Pandey Saroj Kumar Chapagain Futaba Kazama 《Environmental Earth Sciences》2010,60(6):1329-1342
Kathmandu Valley aquifer in central Nepal is continuously under stress since the commencement of mechanized extraction of
groundwater resources in early 1970s. Many wells have been drilled in shallow and deep aquifers of the valley; and numerous
studies have been made in last four decades to understand the aquifers. However, up-to-date information on well inventory,
water extraction, water quality and overall situation of groundwater environment are not yet known in the absence of institutional
responsibility in groundwater management. This study attempts to evaluate current state of the groundwater environment considering
natural and social system together; to better understand origin of stresses, their state, expected impact and responses made/needed
to restore healthy groundwater environment. The analysis reveals increasing population density (3,150–4,680 persons/km2), urbanization (increase in urban population from 0.61 to 1.29 million) and increasing number of hotels due to tourism (23–62
hotels) during a decade are acting as driving forces to exceed groundwater extraction over recharge (extraction = 21.56 and
recharge = 9.6 million-cubic meter-a-year), decrease in groundwater levels (13–33 m during 1980–2000 and 1.38–7.5 m during
2000–2008), decline in well yield (4.97–36.17 l/s during mid-1980s to 1998) and deterioration in water quality. In the absence
of immediate management intervention with institutional responsibility for groundwater development, regulation and knowledgebase
management (i.e. to facilitate collection, integration and dissemination of knowledge); situation of groundwater environment
are expected to deteriorate further. Groundwater modeling approach may help to suggest appropriate management intervention
under current and expected future conditions. 相似文献
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Tracking IMF Fluctuations Nearby Sun Using Wavelet Analysis: Parker Solar Probe First Encounter Data
Gautam S. P. Silwal A. Bashyal A. Chaudhary K. Khanal M. Ale B. Adhikari B. Poudel P. Karki M. Chapagain N. P. 《Geomagnetism and Aeronomy》2022,62(1-2):138-150
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... 相似文献
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Binod Adhikari Nirakar Sapkota Prashrit Baruwal Narayan P. Chapagain Carlos Roberto Braga 《Solar physics》2017,292(10):149
Geomagnetic disturbances are the results of interplanetary causes such as high-speed streamers (HSSs), interplanetary coronal mass ejections (ICMEs), corotating interaction regions (CIRs), and magnetic clouds. During different forms of geomagnetic disturbances, we observed changes in the count rate at neutron monitors that are kept at various locations. We studied the count rates measured by neutron monitors at four stations at various latitudes during different categories of geomagnetic events and compared them. We analysed five events: a geomagnetically quiet event, a non-storm high-intensity long-duration continuous AE activity (HILDCAA) event, a storm-preceded HILDCAA event, a geomagnetic substorm event, and a geomagnetic moderate storm event. We based our analysis on geomagnetic indices, solar wind parameters, and interplanetary magnetic field (IMF) parameters. We found that the strength of the modulation was least during the quiet event and highest during the storm-preceded HILDCAA. By analysing the cause of these geomagnetic disturbances, we related each decrease in the neutron monitor data with the corresponding solar cause. For the ICME-driven storm, we observed a decrease in neutron monitor data ranging from 6% to 12% in all stations. On the other hand, we observed a decrease ranging from 2% to 5% for the HSS-driven storm. For the non-storm HILDCAA, we observed a decrease in neutron monitor data of about 1% to 1.5%. For the quiet event, the neutron monitor data fluctuated such that there was no overall decrease in all stations. 相似文献
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Recent climate change has brought changes to the water regime that has affected the traditional agro-pastoral production systems
and livelihoods in the Upper Kaligandaki Basin of the Nepal Himalayas. Based on fieldwork and available meteorological and
hydrological data, this paper examines the changing water regime and various adaptation strategies that local farmers have adopted
in this cold arid region. Increasing temperature and decreasing rainfall and snowfall have resulted in a negative water balance.
In this scenario, farmers have implemented six major adaptive strategies in the trans-Himalayan Upper Mustang Valley. 相似文献
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