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1.
Water development in the Green River Basin of Wyoming is projected to increase salinity downstream in the Green River and Colorado River, and thereby increase salinity costs to users of water from these two rivers. Despite these water quality and economic impacts to downstream water users, Wyoming will probably be able to develop its currently unused but allocated water supplies of the Green River Basin. The Colorado River Compact and Upper Colorado River Basin Compact are binding, and protect Wyoming's share of the Colorado River System waters for future use. The argument that water may be used to greater profit downstream is not sufficient to reduce Wyoming's allocation. In addition, the no-injury rule under the appropriation doctrine of law does not appear to protect prior downstream appropriations from increasing salinity in this case.  相似文献   

2.
    
ABSTRACT: Long‐term freshwater transport is an important factor affecting estuarine aquatic ecosystems. In this study, a primitive equation, prognostic, three‐dimensional, hydrodynamic model was applied to Apalachicola Bay, Florida, for the summer and fall seasons of 1993. In response to the river freshwater discharge, tide, and wind forces, the model simulations were used to characterize the long‐term freshwater transport processes in the bay. Analysis of spatial distributions of seasonal average salinity and currents shows that the long‐term freshwater transport was strongly affected by the forcing functions of wind and density gradient in the bay. Average freshwater input was approximately the same in the summer and fall seasons of 1993. However, in the summer season, more freshwater moved to the east direction due to the predominant wind from the west, while in the fall season more freshwater moved to the west in response to the wind primarily from the east. The water column was strongly stratified near the river mouth, and it gradually changed to well mixing near the ocean boundaries. Vertical stratification in the bay changed due to wind‐induced mixing and mass transport. Due to the density gradient effect, surface residual currents carrying fresher water were in the direction from the river toward the Gulf, while the bottom residual currents with saltier water entered the bay from the Gulf of Mexico.  相似文献   

3.
The restoration of degraded systems is essential for maintaining the provision of valuable ecosystem services, including the maintenance of aesthetic values. However, restoration projects often fail to reach desired goals for a variety of ecologic, financial, and social reasons. Feasibility studies that evaluate whether a restoration effort should even be attempted can enhance restoration success by highlighting potential pitfalls and gaps in knowledge before the design phase of a restoration. Feasibility studies also can bring stakeholders together before a restoration project is designed to discuss potential disagreements. For these reasons, a feasibility study was conducted to evaluate the efficacy of restoring a tidal freshwater marsh in the Potomac River near Alexandria, Virginia. The study focused on science rather than engineering questions, and thus differed in approach from other feasibility studies that are mostly engineering driven. The authors report the framework they used to conduct a feasibility study to inform other potential restoration projects with similar goals. The seven steps of the framework encompass (1) initiation of a feasibility study, (2) compilation of existing data, (3) collection of current site information, (4) examination of case studies, (5) synthesis of information in a handbook, (6) meeting with selected stakeholders, and (7) evaluation of meeting outcomes. By conducting a feasibility study using the seven-step framework, the authors set the stage for conducting future compliance studies and enhancing the chance of a successful restoration.  相似文献   

4.
ABSTRACT: A study was performed to identify sources of solute loading to the Dirty Devil River and its major tributaries, in southeastern Utah. A primary goal was to determine the contribution of gypsum dissolution to total dissolved solids concentration, and its potential increase in the future if salinity control measures are instituted. Synoptic field data were collected during the low flow period in October 1983. Data were analyzed using the geochemistry models WATEQF and BALANCE to postulate mineral reactions leading to solute loading. Three known sources of solute loading, involving two different geochemical mechanisms, were clearly discernable. Two additional areas of possible gypsum dissolution were located.  相似文献   

5.
The study was prepared in 1966 for the Bureau of Sport Fisheries and Wildlife, Department of the Interior, for presentation to the United States Army Corps of Engineers which had under study several routes for rediversion of the discharge from the Santee-Cooper Hydro Electric Plant, Steam Plant and Lock. Each rediversion was designed to by-pass the Charleston Harbor and this study and report was concerned with one of those routes–Rediversion Route “B.” The channel was to be designed for a maximum fresh-water flow of 27,500 cfs and a mean flow of 15,500 cfs. The objectives of the study and report were to make an estimate of: (1) the geographical extent of salt marsh waters of which the salinity will be measurably reduced, and (2) the probable accumulation of fresh-water borne sediments in those same waters. Special consultants were Dr. F. H. Kellogg, Memphis State University, and Mr. K. L. Drennan, Gulf Coast Research Laboratory, Mississippi.  相似文献   

6.
ABSTRACT: The Mancos Shale area of the Upper Colorado River basin produces large quantities of solutes. In order to develop an understanding of the mechanism of salt production and to determine the source of salinity, a study of the soluble mineral content (SMC) of Mancos Shale and associated alluvium was undertaken. SMC is highly variable in alluvium and associated surficial Mancos Shale. However, lithomorphological units can be identified in terms of their SMC. Results from this study demonstrate that crusts are leached in deep alluvial fills and they contain somewhat less soluble minerals than underlying Mancos Shale on hillslopes. The crusts are saline, sometimes efflorescent, in shale bedrock channels or where channels abutt against the shale. SMC increases in alluvium with decrease in depth of alluvial fill, does not vary significantly with depth in deep of alluvial fills, and increases with depth in shallow ones.  相似文献   

7.
ABSTRACT: The salinity of the lower South Platte River in Colorado is characterized by plotting the average annual flow, total dissolved solids, and salt mass flow against distance along the stream. The plots show that salts are being leached from the irrigated lands above Greeley and are being deposited on the irrigated lands below Greeley. The salt deposition on the lower lands will result in their salination. The plots show also that fall and winter stream flows carry most of the salt loads. These fall and winter flows are stored in off stream reservoirs for use during the irrigation season. Therefore these salts are transferred to the lower irrigated lands where they accumulate. The salt balance for these lands can be improved by permitting the fall and winter flows to leave the basin, or by providing adequate land drainage coupled with supplemental irrigation water.  相似文献   

8.
根据新兴城市东营市严重缺乏淡水资源的现实状况和本区内地下淡水资源是由浅层地下淡水、深层地下淡水和淡水透镜体组成的现状,在深入研究本区地下淡水的补给和动态变化的基础上,提出了从补给、开采和利用等各个层次上采取开源节流、循环利用、科学规划等方式,实现本区地下淡水资源的可持续利用.  相似文献   

9.
ABSTRACT: Sequential water reuse by various users, i.e., municipal, industrial, agricultural, is common practice in all river systems. In the arid and semiarid western United States where streams are not large and water demands are high relative to the virgin water supply, the practice causes a reduction in stream flow and an increase in stream salinity. This paper outlines a quick and easy application of the materials balance principle to approximate the effects of increasing the level of sequential reuse on residual stream flow and salinity.  相似文献   

10.
ABSTRACT: This study emphasized a field investigation of salt release to overland flow from Mancos shale lands of the Price River Basin, Utah. Although a high degree of natural variation existed in the data, which precluded the separation of factors affecting diffuse salt loading that occurs during overland flow, a simplistic nonpoint source loading function developed on empirical concepts was fit to the data. This function was then used to calculate the average annual salt yield to the Price River by overland flow. It was found that even under severe conditions, the salt yields from Mancos shale lands due to overland flow is relatively minor, accounting for less than 1.5 percent of the average annual salt mass transported from the basin by the Price River.  相似文献   

11.
经济发展与耕地变化的关系--以江苏省为例   总被引:5,自引:0,他引:5  
一直以来,对于经济发展与耕地变化间的关系问题,许多学者都认为两者是负相关的关系.辨证地分析了经济发展与耕地变化之间的关系,并结合对江苏省的实证研究,对这一问题有了更深的认识:即经济发展对耕地变化不仅有负面作用,还在一定程度上存在着正向作用.从总体来看,经济发展所消耗的耕地数量将先上升后下降,呈现明显的倒"U"型曲线状.  相似文献   

12.
    
The Clinch River is located in northeastern Tennessee (TN) and southwestern Virginia (VA) of the United States, and contains a diverse mussel assemblage of 46 extant species, including 20 species listed as federally endangered. To facilitate quantitative monitoring of the fauna, quadrat data were collected from 2004 to 2009 at 18 sites in the river, including 12 sites in TN and 6 sites in VA. Thirty‐eight mussel species were collected alive in total from quadrat samples taken annually at sites in the TN section of the river. Over the five‐year study period, mussel density averaged 25.5 m?2 at all sites sampled in TN. In contrast, mussel density averaged only 3.1 m?2 at sites sampled in VA. The best historical site in VA was Pendleton Island in Scott County, where mussel density was estimated as high as 25 m?2 in 1979, comparable to current densities recorded in TN. Mussel densities are now <1 m?2, indicating a collapse of the fauna. A severe reduction in mussel abundance has occurred in a 68‐km section of the river from St. Paul, VA, downstream to approximately Clinchport, VA (river kilometers 411.5‐343.3). While the environmental factors responsible for the faunal decline are largely unknown, they must have been severe and sustained to reduce such large populations to their current low levels. Long‐term water and habitat quality monitoring is needed to determine whether environmental degradation is still occurring in the river.  相似文献   

13.
    
ABSTRACT: The penetration of sunlight into the water column plays a critical role in the aquatic ecosystem. This study investigates light attenuation through the water column of the Danshuei River estuary and explores the models for quantifying it. The measurement of photosynthetically active radiation (PAR) indicates that the conventional exponential attenuation of light with depth is a very good model. A light attenuation coefficient may be derived from the PAR measurements at each location. The simpler measurements of Secchi depth (SD) provide an approximate estimate of the attenuation coefficients through an inverse linear relationship. The results also reveal that the amount and kinds of materials, which are either dissolved or suspended in the water, control light attenuation through the water column. However, the linear regression with such a model results in very poor correlation, and a relatively large constant term for the Danshuei River estuary. The regression with salinity yields a good correlation, indicating that the fraction of sea water might be a good parameter for estimating light attenuation coefficient for practical application in the Danshuei River estuary.  相似文献   

14.
ABSTRACT The Colorado River Basin faces the dilemma of an increasing demand for water while presently struggling with salinity concentrations approaching critical levels for some water uses. Based upon projected development salinity concentrations are predicted to exceed 1200 mg/1 at Imperial Dam by the year 2010. Annual losses to the basin economy associated with increased salinity will exceed $50 million by the year 2010. Although methods of controlling salt discharges are relatively unrefined, certain conclusions, based upon Bayesian statistical methods, can be reached. Five basic alternatives for coping with the problem are presented and evaluated in this paper: (1) do nothing; (2) adopt arbitrary salinity standards; (3) limit development; (4) control salt discharges at a cost equal to the cost of doing nothing, or (5) minimize total costs to the basin. Total costs associated with any given alternative, or the given salinity resulting, are the sum of salinity detriments (cost to users for water of increased salinity plus economic multiplier effects) plus the cost of constructing salt discharge control works. These impacts upon basin economy and Colorado River water quality for each alternative are presented and related to questions of equity which will play a role in arriving at any long-term solution to the Basin's problem.  相似文献   

15.
    
As concerns about urban stormwater runoff become more acute and decentralized management gains popularity, there is a need to better understand public attitudes about stormwater management. We surveyed residents in Appalachia to assess knowledge about stormwater runoff, concerns about impacts, efforts to abate runoff on private property, and attitudes towards who should manage and pay for management. The survey also employed a split sample technique to assess how detailed, science-based information documenting negative impacts influences public concern and attitudes toward stormwater management. The results show the majority of respondents know what stormwater runoff is, but they know less about what its impacts are. About a third of respondents have implemented stormwater abatement measures on their property. There is no consensus on who should manage or pay for stormwater management. Providing more detailed science-based information had no influence on respondents’ general concern about stormwater runoff or their attitudes about its management.  相似文献   

16.
ABSTRACT: Federal planners, in proposing the massive main stem Missouri River water developments in Montana and North Dakota, promised economic and social benefits to the local residents. Five main stem dams, Fort Peck, Garrison, Oahe, Big Bend and Fort Randall, were evaluated for community and rural development effectiveness. Thirty-seven development factors were examined and improvements noted. Only small differences were noted between areas with water developments and the control area. Further analysis revealed that water development benefits moved downstream and to existing urban areas. The Missouri River's rural areas and small communities were not developed significantly by the water projects. Several problems associated with water development policy were illustrated by the study. Cultural differences between planners and the population impacted were ignored. Second, the allocation of social costs was not considered and related to this, serious geographic maldistribution of benefits and costs resulted. The differences between pre-development promises and development performance was dramatic. While the large dams remain as landmarks to engineering prowess, the projects need to be evaluated for their success in meeting humanistic development objectives. Major redevelopment may be warranted by such an ex-post evaluation.  相似文献   

17.
芒果称为“热带果王”,百色右江河谷芒果资源丰富。文章分析了右江河谷的生态环境、开发利用芒果的有利条件、效益评价、发展前景预测,以及开发利用的措施。  相似文献   

18.
    
ABSTRACT: Southeastern Montana's Tongue River basin is experienceing rapid development of its extensive coal deposits which is significantly impacting the basin's hydrologic systems. Energy development projects may require more water than is available and threatens to dewater the river, degrade water quality, and endanger aquatic econosystems. The Montana Water Use Act promised to end the uncertainty which has existed in Montana water law. However, serious difficulties have been encountered in implementing the law and Tongue River water rights remain in a state of uncertainty. The Tongue River's water was allocated in 1978 but the division of the river's water is meaningless due to Indian lawsuits and lack of an agreement between Montana and Wyoming concerning the Yellowstone River Compact. Thus water which is hydrologically available may not be legally available.  相似文献   

19.
    
The principles and basic activities of environmentally sound management of freshwater resources and a cost effectiveness methodology, including the criteria of sound management needed to implement it, are outlined. This management is regarded as a means of integrating environmental concerns with the management of the water resources and it assists the implementation of sometimes conflicting objectives of socioeconomic and ecological development. It promotes sustainable development in river basins.  相似文献   

20.
Kenney, Terry A. and Susan G. Buto, 2012. Evaluation of the Temporal Transferability of a Model Describing Dissolved Solids in Streams of the Upper Colorado River Basin. Journal of the American Water Resources Association (JAWRA) 48(5): 1041‐1053. DOI: 10.1111/j.1752‐1688.2012.00667.x Abstract: The application of a nonlinear least‐squares regression model describing the sources and transport of dissolved solids in streams of the Upper Colorado River Basin, and that was calibrated using data from water year 1991, was evaluated for use in predicting annual dissolved‐solids loads for the years 1974 through 1998. Simulations for each water year were run using annual climate data. To evaluate how well the model captures the observed annual variability across the basin, differences in predicted annual dissolved‐solids loads for each simulated year and 1991 were compared with differences in monitored annual loads. The temporal trend of the differences between predicted annual loads for the simulated years and the load for 1991 generally followed the trend of the monitored loads. The model appears to underpredict the largest annual loads and overpredict some of the smaller annual loads. An underprediction bias for wetter years was evident in the residuals as was an overprediction bias, to a lesser degree, for drier years. A regression analysis on the residuals suggests that the underprediction bias is associated with precipitation differences from 1991 and with previously defined downward trends in dissolved‐solids concentrations in the basin. In general, given the representative climatic conditions, the model adequately performs throughout the period examined. However, the model is most transferable to years with climatic conditions similar to 1991.  相似文献   

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