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1.
Prakash Basnyat Lawrence Teeter B. Graeme Lockaby Kathryn M. Flynn 《Environmental management》2000,26(2):153-161
In this study, water quality and basin characteristics data from different basins of the Fish River basin, Baldwin County,
Alabama, were used to develop a valuation model. This valuation model is based on the effectiveness of “contributing zones”
identified and delineated using methods described by Basnyat and others (Environmental Management]1999] 23(4):539–549). The “contributing zone” delineation model suggests that depending on soil permeability, soil moisture,
depth to water table, slope, and vegetation, buffer widths varying from 16 m to 104 m must be maintained to assimilate or
detain more than 90% of the nitrate passing through the buffers. The economic model suggests the value of retiring lands (to
create the buffers) varies from $0 to $3067 per ha, depending on the types of crops currently grown. The total value of retiring
all areas identified by the contributing zone model is $1,125,639 for the study area. This land value will then form the basis
for estimates of the costs of land management options for improving (or maintaining) water quality throughout the study area. 相似文献
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Floodplain forests are flood-dependent ecosystems. They rely on well-timed, periodic floods for the provision of regeneration sites and on tapered flood recession curves for the successful establishment of seedlings. These overbank flood events are described as regeneration flows. Once floodplain forest trees are established, in order to grow they also require adequate, although variable, river stage levels or maintenance flows throughout the year. Regeneration flows are often synonymous with flood flows and only occur periodically. There is a disparity between this need for varied interannual flows over the decadal time frame and the usual annual cycle of flow management currently used by most river management agencies. Maintenance flows are often closer to established minimum flows and much easier to provide by current operational practices.A number of environmental flow methodologies, developed in North America, Australia, and South Africa are described in this review. They include the needs of the floodplain environment in the management and allocation of river flows. In North America, these methodologies have been put into practice in a number of river basins specifically to restore floodplain forest ecosystems. In Australia and South Africa, a series of related holistic approaches have been developed that include the needs of floodplain ecosystems as well as in-channel ecosystems. In most European countries, restoration of floodplain forests takes place at a few localized restoration sites, more often as part of a flood-defense scheme and usually not coordinated with flow allocation decisions throughout the river basin. The potential to apply existing environmental flow methodologies to the management of European floodplain forests is discussed. 相似文献
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Water demand management, or making better use of the water we have — as opposed to augmenting supply — is increasingly proposed as a way of mitigating water-scarcity problems. Moving water away from agriculture to uses with higher economic value is one of the main measures widely seen as desirable. Sectoral "allocation stress" is seen as resulting from the disproportionate share, and inefficient use of water in the agricultural sector. This apparent misallocation is often attributed to the failure of government to allocate water rationally.
This paper revisits this commonly-accepted wisdom and examines the nature of urban water scarcity, showing the importance of economic and political factors, shaped by incentives to decision-makers, and sometimes compounded by climatic conditions. It shows that cities' growth is not generally constrained by competition with agriculture. In general, rather than using a narrow financial criterion, cities select options that go along the "path of least resistance," whereby economic, social and political costs are considered in conjunction. The question of allocation stress is thus reframed into an inquiry of how transfers effectively occur and can be made more effective. 相似文献
This paper revisits this commonly-accepted wisdom and examines the nature of urban water scarcity, showing the importance of economic and political factors, shaped by incentives to decision-makers, and sometimes compounded by climatic conditions. It shows that cities' growth is not generally constrained by competition with agriculture. In general, rather than using a narrow financial criterion, cities select options that go along the "path of least resistance," whereby economic, social and political costs are considered in conjunction. The question of allocation stress is thus reframed into an inquiry of how transfers effectively occur and can be made more effective. 相似文献
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Brian D. Smith A. K. M. Aminul Haque M. Shakhawat Hossain Anisuzzaman Khan 《Environmental management》1998,22(3):323-335
Platanista gangetica ) are threatened in Bangladesh from the effects of dams, large embankment schemes, dredging, fisheries bycatch, directed hunting,
and water pollution. Visual surveys of the section of the Jamuna River located between the divergence of the Old Brahmaputra
River and the confluence of the Padma River and the section of the Kushiyara River located between the Bangladesh–India border
and the confluence of the Korangi River recorded a sighting rate of 0.13 sightings/km (mean group size = 1.8 dolphins) and
0.08 sightings/km (mean group size = 3.8 dolphins), respectively. These sections of river were considered to be priority areas
for investigation because several water development projects have already been constructed and more are planned for the areas.
During the surveys we examined the remains of dolphins caught accidentally in plastic gillnets and observed fishermen catching
the fish species Clupisoma garua using dolphin oil and body parts as a fish attractor. Additional studies are needed to assess the status of dolphins and
effects of water development and fisheries bycatch. Feasibility studies should be conducted on designating dolphin/fish sanctuaries
and creating artificial habitat or enhancing existing habitat in eddy countercurrent scour pools to mitigate deleterious impacts.
The environmental requirements of river dolphins reflect the needs of productive and biotically diverse tropical rivers. 相似文献
6.
A Water Quality Index Applied to an International Shared River Basin: The Case of the Douro River 总被引:2,自引:0,他引:2
A Water Quality Index (WQI) is a numeric expression used to evaluate the quality of a given water body and to be easily understood
by managers. In this study, a modified nine-parameter Scottish WQI was used to assess the monthly water quality of the Douro
River during a 10-year period (1992–2001), scaled from zero (lowest) to 100% (highest). The 98,000 km2 of the Douro River international watershed is the largest in the Iberian Peninsula, split between upstream Spain (80%) and
downstream Portugal (20%). Three locations were surveyed: at the Portuguese–Spanish border, 350 km from the river mouth; 180
km from the mouth, where the river becomes exclusively Portuguese; and 21 km from the mouth. The water received by Portugal
from Spain showed the poorest quality (WQI 47.3 ± 0.7%); quality increased steadily downstream, up to 61.7 ± 0.7%. In general,
the water quality at all three sites was medium to poor. Seasonally, water quality decreased from winter to summer, but no
statistical relationship between quality and discharge rate could be established. Depending on the location, different parameters
were responsible for the episodic decline of quality: high conductivity and low oxygen content in the uppermost reservoir,
and fecal coliform contamination downstream. This study shows the need to enforce the existing international bilateral agreements
and to implement the European Water Quality Directive in order to improve the water quantity and quality received by the downstream
country of a shared watershed, especially because two million inhabitants use the water from the last river location as their
only source of drinking water. 相似文献
7.
Noor ul Hassan Zardari Ian Cordery Ashish Sharma 《Journal of the American Water Resources Association》2010,46(2):412-428
Zardari, Noor ul Hassan, Ian Cordery, and Ashish Sharma, 2010. An Objective Multiattribute Analysis Approach for Allocation of Scarce Irrigation Water Resources. Journal of the American Water Resources Association (JAWRA) 46(2):412-428. DOI: 10.1111/j.1752-1688.2009.00410.x Abstract: In this study, end user (farmer) and decision maker (water allocator) opinions were surveyed and a conjoint analysis (CA) based method was applied to the quantitative and qualitative data to assess the utility associated with each attribute that plays a role in forming the final thinking of the water users. The application of CA for estimating the utility for each attribute level is a novel approach, which helps provide a formal, objective basis for assigning relative scales for each attribute interval within a multiattribute decision-making model. The utilities (part-worths) obtained from the CA have a cardinal scale and were found to be comparable within and across the attributes. A farmers’ survey on five water allocation attributes was completed from 62 farmers and their opinions on the relative importance of attributes were elicited for a subarea of the Indus River Basin. The CA method was then applied to the survey data and the utilities for each attribute level were determined. This allowed, for instance, decisions to be made, which take account of the perceived value of the water and of the availability of local labor to work on the farm. Finally, these interval scales were used within the specification of the ELECTRE multiattribute decision-making method to provide a complete and objective ranking of nine irrigation districts so that the best decisions on water allocation could be made. 相似文献
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Andrew J. Leidner M. Edward Rister Ronald D. Lacewell Allen W. Sturdivant 《Journal of the American Water Resources Association》2011,47(3):597-610
Leidner, Andrew J., M. Edward Rister, Ronald D. Lacewell, and Allen W. Sturdivant, 2011. The Water Market for the Middle and Lower Portions of the Texas Rio Grande Basin. Journal of the American Water Resources Association (JAWRA) 47(3):597‐610. DOI: 10.1111/j.1752‐1688.2011.00527.x Abstract: Regional water management on the United States’ side of the middle and lower portions of the Rio Grande basin of Texas has been aided by a functioning water market since the early 1970s. The water market operates over a region that stretches from the Amistad Reservoir to the Rio Grande’s terminus into the Gulf of Mexico. This article provides an overview of the organizations, institutions, policies, and geographic particulars of the region’s water‐management system and its water market. In recent years, this region has experienced high population growth, periodic droughts, and a reallocation of water resources from the area’s agricultural sector to the municipal sector. Demand growth for potable water and a relatively fixed supply of raw water are reflected in increasing prices for domestic, municipal, and industrial water rights. Rising prices in the presence of scarcity and the transfer of water from lower‐value to higher‐value uses indicate that the market is operating as suggested by economic theory. Reasons for the market’s functionality are presented and discussed. Finally, suggestions are presented which might mitigate potential complications to market operations from aquifer depletion and aid the management of instream river flows. 相似文献
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/ This study evaluates the institutional capacity and performance of the Taipei Water Management Commission. The commission, which manages the Taipei Water Special Area-one of 95 such areas in Taiwan and the only one managed by a supervisory agency-has established a record of water conservation that suggests its utility as a model for managing other protected water resources areas in Taiwan. However, its present institutional structure limits its ability deliver on its mandate. The study identifies a number of problems related to the commission's current institutional structure that need to be addressed if the commission is to serve as a viable model for managing other protected water resource areas in Taiwan.KEY WORDS: Water resources management; Commissions; Institutional capacity; Taiwan 相似文献
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An Interval-Parameter Waste-Load-Allocation Model for River Water Quality Management Under Uncertainty 总被引:1,自引:0,他引:1
A simulation-based interval quadratic waste load allocation (IQWLA) model was developed for supporting river water quality
management. A multi-segment simulation model was developed to generate water-quality transformation matrices and vectors under
steady-state river flow conditions. The established matrices and vectors were then used to establish the water-quality constraints
that were included in a water quality management model. Uncertainties associated with water quality parameters, cost functions,
and environmental guidelines were described as intervals. The cost functions of wastewater treatment units were expressed
in quadratic forms. A water-quality planning problem in the Changsha section of Xiangjiang River in China was used as a study
case to demonstrate applicability of the proposed method. The study results demonstrated that IQWLA model could effectively
communicate the interval-format uncertainties into optimization process, and generate inexact solutions that contain a spectrum
of potential wastewater treatment options. Decision alternatives can be generated by adjusting different combinations of the
decision variables within their solution intervals. The results are valuable for supporting local decision makers in generating
cost-effective water quality management strategies. 相似文献
13.
Ereney Hadjigeorgalis 《Journal of the American Water Resources Association》2008,44(3):594-605
Abstract: Managing drought in agriculture has taken on growing importance as population growth and environmental concerns place increasing pressures on agricultural water use. One alternative for agricultural water resource management in areas of recurrent drought is allocation through market mechanisms. While past research has aimed to explain why farmers are reluctant to participate in already established water markets, this research seeks to identify the appropriate market mechanism given farmers’ preexisting attitudes toward water markets. Statistical analysis of survey data from 166 farmer interviews in the Rio Grande Basin indicate that farmers are significantly more likely to participate in short‐term water mechanisms, such as spot water markets and water banks than in permanent transfer mechanisms, particularly those that fully separate water rights from land. In sharp contrast to expectations, the choice of market mechanism did not differ significantly between farmers based on their a priori intention to buy, sell or both buy and sell in these markets. Choice of market mechanism also did not differ among farmer types although small, lifestyle or hobby farmers clearly preferred spot water markets to other types of short‐term mechanisms. Evaluating these attitudes a priori may help to design more suitable water market mechanisms for the basin. 相似文献
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A milestone in the field of European water protection policy is the European Union’s Water Framework Directive (WFD), which came into force in December 2000 and which integrates the management of European waters in many ways. In this study, we start by focusing on management issues connected to the implementation of the WFD and pose a question: “what type of models would be the most suitable for use in the context of the WFD?” With this question in mind, we aim to establish a set of operational and functional selection criteria for (computer) models whose application is intended to support decision-making related to a particular water management issue. These so-called “benchmark criteria” should help water managers and other model users in choosing appropriate models, e.g., for the WFD implementation purposes. We first describe models and their use in general and then propose an approach for setting the benchmark criteria for models, basing it on the concept of uncertainty management, while keeping firmly in mind the important role of citizens and citizen organizations in water management. The suggested benchmark criteria are in the form of 14 questions through which each model can be evaluated. Finally, the process for testing and refining the benchmark criteria is highlighted. 相似文献
17.
Ecology and culture comprise interacting components of landscapes. Understanding the integrative nature of the landscape is essential to establish methods for sustainable management. This research takes as a unifying theme the idea that ecological and cultural issues can be incorporated through management. As a first step in developing integrative management strategies, information must be collected that compares and contrasts ecological and cultural issues to identify their areas of intersection. Specifically how can local cultural knowledge enable water resource management that reflects cultural and ecological values? This research examines Native American cultural knowledge for setting water resource management priorities in the Wind River Indian Reservation in central Wyoming. A cross-cultural approach is adopted to assess the relationship between indigenous cultural knowledge and Euro-American perspectives through a comparative examination of the Wind River Water Code and Wyoming Water Law. This research indicates that cultural perspectives provide a rich arena in which to examine management issues. Understanding and identifying cultural practices may be an important first step in collaborative resource management between different cultural groups to prevent conflict and lengthy resolution in court. 相似文献
18.
ERIC N. POWELL JOHN M. KLINCK EILEEN E. HOFMANN MARGARET A. McMANUS 《Environmental management》2003,31(1):0100-0121
A hydrodynamic–oyster population model was developed to assess the effect of changes in freshwater inflow on oyster populations
in Galveston Bay, Texas, USA. The population model includes the effects of environmental conditions, predators, and the oyster
parasite, Perkinsus marinus, on oyster populations. The hydrodynamic model includes the effects of wind stress, river runoff, tides, and oceanic exchange
on the circulation of the bay. Simulations were run for low, mean, and high freshwater inflow conditions under the present
(1993) hydrology and predicted hydrologies for 2024 and 2049 that include both changes in total freshwater inflow and diversions
of freshwater from one primary drainage basin to another.
Freshwater diversion to supply the Houston metropolitan area is predicted to negatively impact oyster production in Galveston
Bay. Fecundity and larval survivorship both decline. Mortality from Perkinsus marinus increases, but to a lesser extent. A larger negative impact in 2049 relative to 2024 originates from the larger drop in fecundity
under that hydrology. Changes in recruitment and mortality, resulting in lowered oyster abundance, occur because the bay volume
available for mixing freshwater input from the San Jacinto and Buffalo Bayou drainage basins that drain metropolitan Houston
is small in comparison to the volume of Trinity Bay that presently receives the bulk of the bay's freshwater inflow. A smaller
volume for mixing results in salinities that decline more rapidly and to a greater extent under conditions of high freshwater
discharge.
Thus, the decline in oyster abundance results from a disequilibrium between geography and salinity brought about by freshwater
diversion. Although the bay hydrology shifts, available hard substrate does not. The simulations stress the fact that it is
not just the well-appreciated reduction in freshwater inflow that can result in decreased oyster production. Changing the
location of freshwater inflow can also significantly impact the bay environment, even if the total amount of freshwater inflow
does not change. 相似文献
19.
Residential Water Consumption,Motivation for Conserving Water and the Continuing Tragedy of the Commons 总被引:1,自引:0,他引:1
Corral-Verdugo V Frías-Armenta M Pérez-Urias F Orduña-Cabrera V Espinoza-Gallego N 《Environmental management》2002,30(4):527-535
This paper explores the effect of the perception of externalities (PE) on residential water consumption. Externalities occur
when individuals make decisions that harm others, without concern for the impact or feeling a need to compensate for the harm.
The aim of this study was to investigate whether PE affects people's motivation to conserve water, and, consequently, the
practice of residential water consumption. Two hundred eighty Mexican citizens responded to a questionnaire investigating
how they perceived that other individuals in their community wasted water. Respondents were also asked about their motives
to conserve water, and direct observations of individual water consumption were recorded. Results were processed within a
structural equations model, which revealed that motives to conserve water significantly inhibit water consumption. Since the
perception of externalities also inhibits conservation motives, the resulting effect of PE on water consumption is positive.
This result means that the more people perceive that others waste water, the less their conservation motives, and, therefore,
the more their own water consumption. 相似文献