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1.
Abstract

The Water Evaluation and Planning Version 21 (WEAP21) Integrated Water Resource Management (IWRM) model seamlessly integrates water supplies generated through watershed-scale hydrologic processes with a water management model driven by water demands and environmental requirements and is governed by the natural watershed and physical network of reservoirs, canals, and diversions. This version (WEAP21) extends the previous WEAP model by introducing the concept of demand priorities and supply preferences, which are used in a linear programming heuristic to solve the water allocation problem as an alternative to multi-criteria weighting or rule-based logic approaches. WEAP21 introduces a transparent set of model objects and procedures that can be used to analyze a full range of issues faced by water planners through a scenario-based approach. These issues include climate variability and change, watershed condition, anticipated demands, ecosystem needs, the regulatory environment, operational objectives, and available infrastructure.  相似文献   

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Conclusions The developed theory of the hydrogeothermal origin of earthquakes should be considered sufficiently well-founded and having universal application both to technogenic and to ordinary earthquakes. It has great prospects for developing automatic earthquake warning and counteraction systems.Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 2, pp. 58–61, February, 1990.  相似文献   

4.
Environment and Climate Change Canada has monitored Niagara River water quality in support of the Great Lakes Water Quality Agreement since establishing a fixed site at Niagara-on-the-Lake in 1975. Using over 40 years of data from this site along with the Fort Erie location added in 1983, we examine the status and trends of concentrations and loadings of nutrients and major ions and assess evidence of sources between the two stations. Trends were observed for the majority of measured parameters and there is strong agreement between trends in concentrations and loadings which are generally higher at the downstream site; however, upstream/downstream differences indicate relatively little loading occurs along the length of the river itself. For total phosphorus (TP), inputs from Lake Erie via the Niagara River account for the majority of loading to Lake Ontario and, in some years, exceed the 7000 MTA Lake Ontario target. Between 2014 and 2018, we calculate the mean Niagara River TP loading to be 5275 MTA. We highlight the major changes in water quality constituents over time, including TP, and reveal increased seasonal consumption of TP and SiO2, reflecting potential increases in the biological productivity in Lake Erie. The long and rich Niagara River dataset, which comprises year round sampling (including rare winter data), provides detailed tracking of changing Great Lakes water quality and could be further utilized to assess the impacts of climate change, improve understanding of diatom and harmful algal bloom dynamics, and enhance knowledge of in-lake major ion and nutrient dynamics.  相似文献   

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K. G. Tejwani 《国际水》2013,38(4):150-154
ABSTRACT

A survey of Indian reservoirs has shown that they receive on an average about 200 percent more sediment than the design inflow. The causes are the usual, except that they are operating very intensely. In brief ‘misuse and mismanagement’ of the catchment area will describe the causes of higher rates of sedimentation.

Fortunately India is very much aware of this problem and a lot is being done by identifying the priority areas for treatment and implementation of programmes to reduce soil erosion and sediment generation.

While techniques and efficacy of various biological and structural control measures are well known, it is the policy and planning aspects which need greater attention at present. Some of them are:

—It is important that policy and planning should aim at developing the catchment area, reservoir and command area as a package.

—In the developing world sediment is the greatest pollutant and it must be recognised and treated as such.

A policy for effective water resource and hydropower development, watershed and command area development must take into account the short term and long term, direct and indirect, private and social benefits, and endeavour to involve the people and the employees in such a way that they feel committed to efficient and effective implementation.  相似文献   

7.
Abstract

This paper explores the major determinants of heavy reliance on groundwater and the extent to which conjunctive use of ground and surface water affects the production efficiency of Pakistan’s irrigators. The results show that the major drivers of groundwater use in Pakistan’s agriculture are the variability and uncertainty associated with surface water delivery and that any effort to address the groundwater–energy nexus challenge should first consider fixing the problems associated with surface water supplies. The findings also suggest that having access to groundwater does not directly translate into improvements in technical efficiency of production.  相似文献   

8.
Organochlorine pesticides (OCPs) and polycyclic aromiatic hydrocarbons (PAHs) were analyzed in surface sediment samples collected from Qinghai Lake, the largest lake in China, which is situated in the northeast Qinghai–Tibet plateau at an altitude of 3200 m. The concentrations of these pollutants ranged from 0.02 to 1.00 ng/g for hexachlorocyclohexanes (HCHs), from not detected to 0.86 ng/g for dichlorodiphenyltrichloroethanes (DDTs), from 0.26 to 1.73 ng/g for OCPs, and from 366 to 966 ng/g for PAHs. The predominance of α-HCH suggests that long-range atmospheric transport is an important source for HCHs. A low α- to γ-HCH ratio (3.87 on average) indicates the possible usage of lindane in the drainage basin. The high percentage of p,p′-DDE and p,p′-DDD and the low percentage of o,p′-DDT indicated significant degradation from previous inputs, and no recent inputs of dicofol derived DDT. Based on the analysis of the component ratios, PAHs were found to be primarily from the combustion of biomass and coal-based fossil fuels. Using the Canadian sediment guidelines, PAHs are of greater ecological concern than OCPs in Qinghai Lake.  相似文献   

9.
Teachers have an opportunity to create awareness of the importance of the Great Lakes by incorporating lake examples of major science/social concepts into their curricula. A survey of 300 middle school science teachers in watershed counties of Great Lakes states and Ontario revealed topics that were highest priority and that teachers wanted to know more about: water quality, environmental responsibility, water uses and conservation, and toxic chemicals. Topics of lowest priority were those dealing with shipping, water diversion, human history, careers and hobbies, and aesthetics (art, music, and literature of the lakes). Reasons for not including low priority topics were primarily based on their not being a part of the assigned curriculum for the responding science teachers. Responses regarding topic priorities and knowledge did not differ significantly by state/province, gender, grade level taught, early vs. late response, or whether the teachers had participated in a Great Lakes education workshop, with the primary exception that teachers who had been in a workshop generally rated exotic species as more important and were teaching more about it. Teachers claim to get most of their Great Lakes information from workshops and classes, with newspapers as the primary mass media source. They prefer to receive instructional materials in the form of classroom-ready activities and units, and when they seek additional education they prefer one-day or summer workshops for college credit. Providers of Great Lakes education resources should consider teacher preferences in designing materials and experiences, and consider infusion as a means of introducing non-science topics into science classes.  相似文献   

10.
《小水电新闻》2004,21(76):25-30
4 HYDROPOWER DEVELOPMENT 4.1 History of hydropower 4.1.1 Beginning of the development of hydropower In Japan, 1860 to 1890 was thc period of rapid development of the modem State and the establishment of centralized authority. After constructing the framework for the modem State, the Government pursued a policy of economic modernization.New industries were stimulated by establishing Government-managed  相似文献   

11.
1. Barriers & Mitigation to Commercialization of Small Hydel Power Plants In Pakistan 1.1 Institutional Barriers In Pakistan, research, development and implementation of small & micro hydel power on commercial scale has been hampered by a lack of cordination, institutional support, poor definition of mandates and responsibilities of the organizations. Until May, 2003, there was not a single central agency with the overall responsibility for policy, planning, targets, co-ordination and strategic management of this sector, although there were a number of disparate bodies set up with limited objectives and little coordination amongst different stakeholder.  相似文献   

12.
Studies that evaluate the linkages between watershed improvement through Best Management Practices (BMPs) and downstream outcomes are few. Water quality of coastal waters is often impacted by soil and nutrient loss from watersheds in agriculture. Mitigation of these impacts is of concern in the Great Lakes, the Finger Lakes Region of New York State, and generally in water bodies of North America. In this issue, we report on hypothesis-based research at the watershed level evaluating the impact of BMPs on mitigation of nonpoint sources of nutrient and soil loss to streams and the nearshore zone of a lake. Specifically, we hypothesize not only reductions in nutrient and soil losses from watersheds but also a resultant decrease in metaphyton (filamentous algae), coliform bacteria, and macrophyte populations in the nearshore at stream mouths draining sub-watersheds where BMPs were introduced. Small experimental sub-watersheds, predominantly in agriculture (> 70%), were selected to ensure that effects on downstream systems would not be confounded by other land use practices often observed in large watershed approaches. In this introductory paper, we provide background information on Conesus Lake, its watershed, and the Conesus Lake watershed project, a large multi-disciplinary study evaluating agricultural management practices. The series of papers in this volume consider the effect of BMPs designed to control nonpoint sources on water chemistry, metaphyton, macrophytes, and microbial populations in the coastal zone of a lake. Ultimately, this volume expands the basic understanding of the ability of BMPs to control nonpoint source pollution while contributing toward the goal of improving water quality of downstream systems including streams, embayments, and the nearshore of large lakes.  相似文献   

13.
Sarah Wade 《国际水》2018,43(8):1026-1039
ABSTRACT

Both social and environmental justice overlap with water (in)security, but neither fully captures the nuances. This review extends a water justice framework by critiquing and further developing an existing environmental justice framework. Testing a reformulated understanding of water security through a case study reveals added insights derived from inclusion of scale and power dynamics.  相似文献   

14.
ABSTRACT

The major hydroclimatic cause of the 1993 Upper Mississippi River Basin flood was the persistence of heavy rains over a period of several months. As a result, precipitation totals for April-September 1993 were unprecedented, exceeding by a large margin any previous six-month precipitation total since 1895. Using standard hydrometeorological methods, the frequency of occurrence of these precipitation totals is expected to be less than once every 200 years. The core of the heavy rain area was located in Iowa and Missouri near the main stems of the Mississippi and Missouri Rivers. Thus, runof from many of the heavy rain events was deposited directly into these main stems. The persistence of the heavy rains maintained high soil moisture levels throughout the summer period. Thus, the heavy rains during the summer were accompanied by very high runoff rates. Also, the frequent rains were accompanied by many cloudy days. Primarily for this reason (and to a lesser extent because of lower temperatures), potential evapotranspiration was considerably below the long-term average. This was a contributing factor to maintaining the high soil moisture levels and high runoff.  相似文献   

15.
Bivariate gamma distributions have been used successfully on modeling hydrological processes. In this work, supposing that X and Y follow the Crovelli’s bivariate gamma model, we deduce the exact distributions of the functions U?=?X?+?Y, P?=?XY and Q?=?X/(X?+?Y), as well as their respective moments. Those functions are important hidrological variables. A MAPLE code to compute the quantiles is provided. An application of the results is provided to rainfall data from Passo Fundo.  相似文献   

16.
Changes in precipitation exerts a huge impact on human beings and it is of vital importance to study the regular pattern of meteorological and hydrological factors. In order to explore the changing patterns of precipitation in Sichuan province in west China during 1961–2008, several precipitation related indices were analysed by the Mann–Kendall test. For monthly precipitation, significant increasing trends are mainly found during January, March and June, while significant decreasing trends mostly are observed during July, September and October. Most of extreme precipitation indices are decreasing. Especially the annual total precipitation in wet days and maximum number of consecutive wet days show significant negative trends. Furthermore, the spatial and temporal variation of dryness/wetness has been assessed by Standardized Precipitation Index (SPI) and principal component analysis (PCA) on 24-month time scales. The results demonstrated noticeable spatial patterns with several sub-regions characterized by different trends: a remarkable dry tendency prevails in central and east Sichuan, while the other areas are dominated by a wet tendency.  相似文献   

17.
This article provides a review of trade-offs and synergies of bioenergy within the water–energy–food security nexus, with emphasis on developing countries. It explores the links of bioenergy with food security, poverty reduction, environmental sustainability, health, and gender equity. It concludes that applying the nexus perspective to analyses of bioenergy widens the scope for achieving multiple-win outcomes along the above aspects.  相似文献   

18.
In the western US–Mexico border region, both countries’ authorities look to desalination as a means to meet increased demands for dwindling supplies. In addition to several existing or planned desalination plants, plans exist to develop projects along Mexico’s coasts to convert seawater into freshwater primarily for conveyance and consumption in the United States. Even though desalination systems have the potential to increase water supply in the region, there are associated consequences, costs and constraints. To understand the impacts of such binational desalination systems, this paper assesses, through a water-security framework, the case of a proposed desalination plant on the Upper Gulf of California. The analysis suggests that for binational desalination systems, there are several key areas of impact against which the benefits of increased water supply must be weighed.  相似文献   

19.
We assessed the reproductive potential of various genetic strains of hatchery lake trout (Salvelinus namaycush) in southern and eastern Lake Ontario from indices of fecundity and indices of male abundance. Indices were constructed from catches of mature lake trout in gill nets during September 1980 to 1994 after correcting for mortality from sea lampreys (Petromyzon marinus) which occurred between September sampling and late fall spawning. Strain and age were assigned to individual lake trout based on clipped fins and maxillary bones or coded wire tags. Fecundity-length relationships for fish of the same age, determined from mature females collected in 1977 to 1981 and 1994, were not different (P > 0.05) among genetic strains. For all strains combined, fecundity-length relationships in 1977 to 1981 were not different among fish of various ages but in 1994, age-5 and -6 fish had fewer eggs (P < 0.003) than age-7 fish, and age-7 fish had fewer eggs (P < 0.003) than fish of age 8, 9, or 10. Annual indices of fecundity varied 19 fold and indices of mature males varied 11 fold; both indices were low in the early 1980s, increased sharply in the mid 1980s, and peaked in 1993. The strain which dominated fecundity and mature male indices shifted during the study from Seneca Lake strain to Lake Superior strain and then back to Seneca Lake strain. However, changes in either reproductive potential or genotypes do not appear responsible for the abrupt appearance of naturally-produced yearling lake trout throughout southern and eastern Lake Ontario in 1994–1995, the first widespread occurrence of juveniles produced by hatchery lake trout in Lake Ontario.  相似文献   

20.
A survey of young adults was conducted at several 3rd level agricultural institutions across Ireland over a 6-month period. The results from the agri-student survey were compared and contrasted with those of an identical survey of private well owners. Students (n?=?246) scored significantly lower than well owners (n?=?245) in two developed metrics, namely “groundwater source awareness” and “groundwater contamination awareness” (p?n?=?476). Clusters comprised four predictors: presence of an elderly householder (predictor importance = 0.91), residence within the household during well design (predictor importance = 0.55), presence of an infant or young child (≤5 years) in the household (predictor importance = 0.48) previous instance of gastrointestinal illness or symptoms within the household (predictor importance = 0.31) The results of this research may be used to inform future risk management, communication and knowledge transfer policies, which are currently required to ensure the safeguarding of private groundwater supplies both in Ireland and further afield.  相似文献   

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