Littérature scientifique sur le sujet « Impaired river »
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Articles de revues sur le sujet "Impaired river"
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Sajina, Aliyamintakath Muhammadali, Deepa Sudheesan, Srikanta Samanta, Samir Kumar Paul, Sanjay Bhowmick, Subir Kumar Nag, Vikas Kumar et Basanta Kumar Das. « Development and validation of a fish-based index of biotic integrity for assessing the ecological health of Indian Rivers Mahanadi and Kathajodi-Devi ». Aquatic Ecosystem Health & ; Management 25, no 2 (1 avril 2022) : 25–35. http://dx.doi.org/10.14321/aehm.025.02.25.
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Abstract India has a vast network of 14 major rivers and their tributaries, covering 83% of the drainage basin and accounting for 85% of the surface flow. Anthropogenic activities like damming, channel modification, water abstraction, sewage and effluent disposal, sand mining, unthoughtful exploitation of biotic resources, etc. are the major threats faced by the rivers in the country. Monitoring protocol of Indian rivers lacks an integrated approach based on judicious use of both abiotic and biotic components as well as a total lack of consideration for ecological health. Index of Biotic Integrity is a flexible multimetric index that can be modified and adapted to the various zoogeographic regions of the world. A fish-based multi-metric IBI was developed by modifying and incorporating metrics that are sensitive to the various ecological stressors faced by Indian rivers, fishes being excellent indicators of river health. The adapted IBI was validated and used to assess ecological health of two rivers—Mahanadi, and its distributary Kathajodi-Devi—flowing through central-eastern India. The study indicated that in River Mahanadi, around 25% of the freshwater river stretch was slightly impaired and the remaining 75% stretch was moderately impaired. In Kathajodi-Devi, most of the river stretches were in a moderately impaired condition, except at Italnga stretch where the river was severely impaired. The Index of Biotic Integrity scores estimated could reflect the ecological health of the rivers. The study shows that use of Index of Biotic Integrity is a useful and reliable approach to assess the health conditions of Indian aquatic resources warranting initiatives to be taken to implement and incorporate it into the country's water resource management.
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Kasahara, Tamao, Thibault Datry, Michael Mutz et Andrew J. Boulton. « Treating causes not symptoms : restoration of surface - groundwater interactions in rivers ». Marine and Freshwater Research 60, no 9 (2009) : 976. http://dx.doi.org/10.1071/mf09047.
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Many river restoration projects seek to address issues associated with impaired hydrological and ecological connectivity in longitudinal (e.g. effects of dams, weirs) or lateral (e.g. alienated floodplain) dimensions. Efforts to restore the vertical dimension of impaired stream–groundwater exchange are rare, hampered by limited understanding of the factors controlling this linkage in natural alluvial rivers. We propose a simplified two-axis model of the ‘primary drivers’ (sediment structure and vertical hydraulic gradient) of stream–groundwater exchange that acknowledges their interaction and provides a practical template to help researchers and river managers pose hypothesis-driven solutions to restoration of damaged or lost vertical connectivity. Many human activities impact on one or both of these drivers, and we review some of the tools available for treating the causes (rather than symptoms) in impacted stream reaches. For example, creating riffle-pool sequences along stream reaches will enhance vertical hydraulic gradient, whereas flushing flows can remove clogging layers and sustain sediment permeability. Our model is a first step to specifying mechanisms for recovery of lost vertical connectivity. Assessing results of river restoration using this approach at reach to catchment scales will provide scientific insights into the interplay of hydrology, fluvial geomorphology and river ecosystem function at appropriately broad scales.
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Hinds, L., et D. Goldney. « A Comparison of Plasma Testosterone and Progesterone Levels in The Thredbo and Duckmaloi River Platypuses Over a Twelve Month Cycle. » Australian Mammalogy 20, no 2 (1998) : 305. http://dx.doi.org/10.1071/am98311.
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A 1-2 ml blood sample was removed from the bill sinus of 208 captured platypuses from the Duckmaloi and Thredbo Rivers over the period January 1991-March 1993. Platypuses from the Duckmaloi were sampled monthly during 1992 and in February, August and December from the Thredbo River in the same year. The numbers and sex of platypuses sampled are recorded in the following Table. Samples were stored on ice and plasma separated from blood cells within 24 hours of sampling by centrifugation for I0 minutes and the supernatant stored at -20°C. The changes in plasma testosterone and progesterone for platypuses from both rivers were compared over a 12 month cycle. The levels of these two hormones were considerably less in the breeding season in the Thredbo River platypuses than in those from the Duckmaloi River. Peak plasma progesterone levels of the order of 90 ng/ml were measured in the Duckmaloi River females compared to levels of <5 ng/ml in Thredbo River females. Male plasma testosterone levels in animals from the Duckmaloi River peaked around 15 ng/ml, whereas Thredbo River males had levels of around 6 ng/mI. These data suggest that over the period of the two year study, platypus breeding potential in the Thredbo River was significantly impaired.
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Nayamatullah, M. M. M., S. Bin-Shafique et H. O. Sharif. « A study to estimate the fate and transport of bacteria in river water from birds nesting under a bridge ». Water Science and Technology 68, no 12 (24 octobre 2013) : 2568–75. http://dx.doi.org/10.2166/wst.2013.521.
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To investigate the effect of input parameters, such as the number of bridge-dwelling birds, decay rate of the bacteria, flow at the river, water temperature, and settling velocity, a parametric study was conducted using a water quality model developed with QUAL2Kw. The reach of the bacterial-impaired section from the direct droppings of bridge-nesting birds at the Guadalupe River near Kerrville, Texas was estimated using the model. The concentration of Escherichia coli bacteria were measured upstream, below the bridge, and downstream of the river for one-and-a-half years. The decay rate of the indicator bacteria in the river water was estimated from the model using measured data, and was found to be 6.5/day. The study suggests that the number of bridge-dwelling birds, the decay rate, and flow at the river have the highest impact on the fate and transport of bacteria. The water temperature moderately affects the fate and transport of bacteria, whereas, the settling velocity of bacteria did not show any significant effect. Once the decay rates are estimated, the reach of the impaired section was predicted from the model using the average flow of the channel. Since the decay rate does not vary significantly in the ambient environment at this location, the length of the impaired section primarily depends on flow.
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Farag, Aïda M., Mark A. Stansbury, Harold L. Bergman, Christer Hogstrand et Elizabeth MacConnell. « The physiological impairment of free-ranging brown trout exposed to metals in the Clark Fork River, Montana ». Canadian Journal of Fisheries and Aquatic Sciences 52, no 9 (1 septembre 1995) : 2038–50. http://dx.doi.org/10.1139/f95-795.
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Tissue metal accumulation and physiological responses were measured in brown trout (Salmo trutta) collected from two sites on the Clark Fork River, Montana, and two reference sites to determine the health status of the resident fish population. Concentrations of metals in tissues, products of lipid peroxidation, and microscopic Cu inclusions were significantly higher in fish collected from the upper Clark Fork River site than in fish from reference sites. Metallothionein concentrations were higher in the livers of fish from the upper Clark Fork River than in those of fish from reference sites. The health of the fish population in the upper Clark Fork River is probably impaired because of previously reported elevated concentrations of metals including As, Cd, Cu, Pb, and Zn in the surface water and aquatic invertebrates in the upper Clark Fork River. The high concentrations of metals in the surface waters and sediments of the Clark Fork River are typical of rivers in the intermountain western United States where discharges from mining activities have occurred since the late 1800s. Thus, our findings can be used as a guide for researchers throughout the intermountain western United States who may investigate similar field conditions.
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Meng, Han, Yuanyuan Lin, Wenjun Zhong, Zheng Zhao, Liang Shen, Zhen Ling, Kaisong Zhao et Shan Xu. « Fish Biomonitoring and Ecological Assessment in the Dianchi Lake Basin Based on Environmental DNA ». Water 15, no 3 (18 janvier 2023) : 399. http://dx.doi.org/10.3390/w15030399.
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Fish are among the main target groups when conducting biomonitoring and ecological assessment of aquatic environments. Environmental DNA (eDNA) metabarcoding provides a unique opportunity to enhance biomonitoring throughput, precision, and standardization. However, few fish monitoring studies based on eDNA metabarcoding have been conducted at the basin scale. Taking Dianchi Lake and the three inflowing rivers (Panlong River, Baoxiang River, and Chai River) as research objects, this study monitored fish diversity via eDNA metabarcoding, and the Fish Index of Biological Integrity (F-IBI) was constructed and applied for the ecological assessment of the aquatic environment. Here, we detected 41 species belonging to 9 orders, 15 families, and 35 genera in the sampling areas, including 17 native fish species such as Hemiculter leucisculus, Cyprinus carpio, and Silurus soldatovi. Distinct diversity patterns were observed among Dianchi Lake and the three inflowing rivers. Particularly, the fish diversity of Panlong River was richer than that of Dianchi Lake, Baoxiang River, and Chai River. Water temperature (WT), chemical oxygen demand (COD), total nitrogen (TN), and total phosphorus (TP) significantly influenced the distribution of fish communities in most sampling sites of the Dianchi Lake basin (p < 0.05). Moreover, according to the F-IBI assessment system, 25% of the sampling sites were defined as ‘fine’ or above, and 75% were ‘impaired’ or below. This study provided insights into the ecological restoration and precise management of the aquatic environment of the Dianchi Lake basin.
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Vidal, Tânia, Joana I. Santos, Catarina R. Marques, Joana L. Pereira, Maria Teresa Claro, Ruth Pereira, Bruno B. Castro, Amadeu Soares et Fernando Gonçalves. « Resilience of the macroinvertebrate community of a small mountain river (Mau River, Portugal) subject to multiple stresses ». Marine and Freshwater Research 65, no 7 (2014) : 633. http://dx.doi.org/10.1071/mf13207.
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Freshwaters commonly face human pressure, which produces multiple stressor scenarios that may threaten their ecological status. Biotic community assessments are useful tools to monitor such changes, and the European Water Framework Directive (WFD) has brought this into the legislative framework. The present study focused on a small mountain river facing multiple stresses, with the purpose of (1) evaluating the sensitivity of the macroinvertebrate community to the stresses, (2) assessing whether the ecological status was impaired in different years and (3) comparing the WFD approach with more refined community analyses. The river was generally in a very good ecological state. Despite seasonal and inter-annual fluctuations, no evident stressor-related effects were detected. We hypothesise that the observed resilience was the result of (1) the current dormant state of the abandoned mining areas (the most relevant potential source of contamination) and (2) the naturalness and strong current of the river, which buffered the impacts of contamination. Such a pattern may be generally valid for small mountain rivers, making them therefore more resilient to stresses. Nevertheless, small changes in community structure in the lowest reach of the river – undetected by the WFD assessment scheme – suggest that some disturbance was present, signalling the need for intervention by managers.
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Pradilla, Gonzalo, Georg Lamberty et Johannes Hamhaber. « Hydromorphological and socio-cultural assessment of urban rivers to promote nature-based solutions in Jarabacoa, Dominican Republic ». Ambio 50, no 8 (1 juin 2021) : 1414–30. http://dx.doi.org/10.1007/s13280-021-01565-3.
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AbstractIn Latin America and the Caribbean, river restoration projects are increasing, but many lack strategic planning and monitoring. We tested the applicability of a rapid visual social–ecological stream assessment method for restoration planning, complemented by a citizen survey on perceptions and uses of blue and green infrastructure. We applied the method at three urban streams in Jarabacoa (Dominican Republic) to identify and prioritize preferred areas for nature-based solutions. The method provides spatially explicit information for strategic river restoration planning, and its efficiency makes it suitable for use in data-poor contexts. It identifies well-preserved, moderately altered, and critically impaired areas regarding their hydromorphological and socio-cultural conditions, as well as demands on green and blue infrastructure. The transferability of the method can be improved by defining reference states for assessing the hydromorphology of tropical rivers, refining socio-cultural parameters to better address river services and widespread urban challenges, and balancing trade-offs between ecological and social restoration goals.
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Garcier, R. J. « Rivers we can't bring ourselves to clean – historical insights into the pollution of the Moselle River (France), 1850–2000 ». Hydrology and Earth System Sciences Discussions 4, no 3 (15 juin 2007) : 1697–727. http://dx.doi.org/10.5194/hessd-4-1697-2007.
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Abstract. As products of both natural and social systems, rivers are highly complex historical objects. We show in this paper that historical analysis works on two different levels: one level, which we call "structural", shows the materiality of the riverine environment as the spatial-temporal product of natural factors and human impacts (bed and course alterations, pollution, etc.). On a second level – "semiotic" – we show that river systems are also social constructs and the subjects of ancient and diverse management practices. The quality of a river will be a function of the dialectical interaction between both levels. Historical analysis can uncover the inherited constraints that bear upon current management practices. To help substantiate this analytical framework, we analyse the case of the Moselle river in eastern France by using archival sources and statistical data. Severely impaired by industrial discharges from iron, coal and salt industries between the 1875s and the early 1980s, the waters of the Moselle became the subject of a social consensus between stakeholders that prevented the implementation of efficient pollution management policies until the 1990s. The example urges caution on the pervasiveness of participatory approaches to river management: social consensus does not necessarily benefit the environment.
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Garcier, R. J. « Rivers we can't bring ourselves to clean – historical insights into the pollution of the Moselle River (France), 1850–2000 ». Hydrology and Earth System Sciences 11, no 6 (6 novembre 2007) : 1731–45. http://dx.doi.org/10.5194/hess-11-1731-2007.
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Abstract. As products of both natural and social systems, rivers are highly complex historical objects. We show in this paper that historical analysis works on two different levels: one level, which we call "structural", shows the materiality of the riverine environment as the spatial-temporal product of natural factors and human impacts (bed and course alterations, pollution, etc.). On a second level –"semiotic" – we show that river systems are also social constructs and the subjects of ancient and diverse management practices. The quality of a river will be a function of the dialectical interaction between both levels. Historical analysis can uncover the inherited constraints that bear upon current management practices. To help substantiate this analytical framework, we analyse the case of the Moselle river in eastern France by using archival sources and statistical data. Severely impaired by industrial discharges from iron, coal and salt industries between the 1875s and the early 1980s, the waters of the Moselle became the subject of a social consensus between stakeholders that prevented the implementation of efficient pollution management policies until the 1990s. The example urges caution on the pervasiveness of participatory approaches to river management: social consensus does not necessarily benefit the environment.
Thèses sur le sujet "Impaired river"
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Carothers, Taya L. « Justice and the River : Community Connections to an Impaired Urban River in Salt Lake City ». DigitalCommons@USU, 2018. https://digitalcommons.usu.edu/etd/7381.
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Local communities have the right to participate in decision-making about environmental resources near where they live. Local governments have tried to gather feedback from communities to help improve the decisions they make, but have not always done a good job getting feedback from minority or urban communities. This dissertation provides one step toward obtaining this kind of public input in a majority minority community surrounding the Jordan River in Salt Lake City. Children and adults participated in this research. I present findings from two surveys, from work with children, and from adult interviews to understand how this community relates to their local river, what they like and do not like about it, and what they would like to see improved.
This research revealed that communities have both positive and negative views of the river, but overall see it as an important community resource that is highly valued. Communities would like to participate more in river decision-making and have suggestions for how they would like to see that happen. The results in this dissertation can help bridge the gap between local city government officials and this minority community to help improve the river environmental quality and connections to the community.
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CABRINI, RICCARDO. « Multilevel structure-function relationship in impaired stream ecosystems . From theory to management applications ». Doctoral thesis, Università degli Studi di Milano-Bicocca, 2013. http://hdl.handle.net/10281/42256.
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Increasing urbanization across the world has led to increased research on ecology in urban settings in the last decade. Urban ecological studies have investigated both impacts of urban development on native ecosystems and the dynamics of urban environments themselves as ecosystems. In both areas of research, streams of urban areas have an important part to play because their position in the landscape makes these ecosystems particularly vulnerable to impacts associated with landcover change.
Urban stream ecosystems are affected by multiple stressors and their effects are synthetized in the “urban stream syndrome” theorized in Walsh et al. 2005. Consistent symptoms of the urban stream include flashier hydrograph, elevated concentrations of nutrients and contaminants, altered channel morphology and stability and reduced biodiversity, with increased tolerant species. These ecological effects are often accompanied by other symptoms not observed in all urban areas, such as reduced baseflow and increased suspended solids.
In impaired freshwater ecosystems, it is known that ecological integrity can be subdivided into two components, structural and functional integrity. Structural indicators of ecosystem health may be defined as the qualitative and quantitative composition of biological communities. Fish and macroinvertebrate assemblages have been the main focus for assessing structural integrity, although a variety of alternative targets such as benthic algal communities, protozoans, and macrophytes have also been used.
Macroinvertebrate assemblages play a central ecological role in many stream ecosystems and are among the most ubiquitous and diverse organisms in fresh waters. Macroinvertebrates are easily recognizable and classifiable and some taxa are representative of every different habitat and condition (sensibility or tollerance to pollution and environmental changes) and so it is easy to aggregate results of macrobenthos analyses into synthetic indeces (such as STAR_ICMi). Function indicators instead, that have a much shorter history, are complementary to structural indicators and refer to the autoecology of biological communities and ecological attributes within the ecosystem in which they are located.
In Water Framework Directive, develops by European Union to advance more comprehensive water legislation, the river basins with above mentioned characteristics are defined heavily modified water bodies (HMWBs).
HMWBs have unique water quality characteristics that, in most cases, are comparatively different from normal stream conditions upstream of the discharge or at regional reference sites. Reference sites are commonly used in bioassessment studies to identify undisturbed or pristine conditions and hence management targets. The increase of urban development often results in the absence of reference sites in HMWBs and this leads in difficulties to define a target condition for restoring urban stream sites.
The WFD requires that all waters achieve good ecological status and only slightly deviate from natural reference conditions, which has become the main objective of most restoration projects in Europe. The ecological status is quantified in many European member states using multi-metric indices, and good ecological status corresponds to a specific score value. However, there is little information on the limiting effects of large-scale pressures on the biological metrics.
As suggested by numerous research works, the scale to approach river investigations can be considered from the microhabitat level to basin scale. A river may be analysed across a variety of levels, which can be ordered into a hierarchy, with different degree of sensitivity and recovery time.
Impacts of human activity are becoming increasingly unacceptable to a global community that focuses on environmental sustainability. Therefore, whole catchment approach management have been developed to preserve stream ecosystems or restore damaged ecosystems, and mitigate against further damage.
The individuation of which factors set limits to biological community development and their respective values is of great interest for river managers and river restoration campaigns. In urban streams is usually hard to assess causal relationships among specific stressors and responses of biological communities using the most common statistical tools. Using macroinvertebrate assemblages as biological indicators in micro- and mesohabitat level works, applied statistics may be viewed as an elaboration of the linear regression model and associated estimation methods of least square.
In whole basin analyses, data variability is high and classic statistical approach may even become uninformative. Moreover, the effects of many stressors (local and global) may influence simultaneously the response of biological community leading to a decrease of statistical model fit.
In this perspective, alternative statistical approaches are necessary. In 1978 Koenker and Bassett theorized the quantile regression in econometric sciences, a robust alternatives to the least squares estimator for the linear model. Other authors introduced this kind of regression in ecology declaring that quantile regression allows the various stressors to be considered as “constraints” to the distribution of biological communities, without compromising the model causal relationship.
Aim of this work is to assess the overall pressure of human activities in river basins of Lombardy piedmont and floodplain area and to relate changes in the biological communities as a result of habitat loss and changes in both hydromorphological and physico-chemical properties. In this area, many rivers have a “channelized” nature with straight section, clear of river bank tree and uniform bed morphology. Flow regulation and modification have also been widespread. The quantity and timing of water availability have been altered for irrigation and industrial purposes, through the construction of dams and reservoir for water supply. Changes in water quality are also common, in particular in lowland areas where urbanization and agriculture are more strong.
For these reasons, the work is focusing on different scale (microhabitat, site, river reach and basin levels) to have a better resolution and understanding of existing dynamics among structural and functional indicators and pressures in impaired environments. These areas undergo different stresses (habitat loss, changes in physico-chemical properties and changes in flow) that affect the integrity of the ecosystems. Assessing the condition of ecosystems is a prerequisite to reduce the induced anthropogenic pressure. Decision-making in river restoration programs can also be helped by multilevel kind of information.
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BENVENUTO, FEDERICA. « Integrated study of chemical, hydrological and biological aspects of impaired rivers to support restoration strategies ». Doctoral thesis, Università degli Studi di Milano-Bicocca, 2009. http://hdl.handle.net/10281/7504.
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The human presence and activities affect the environmental quality of water bodies in different ways. Pressures concern various aspects of the overall environmental quality and their effects are cumulative and synergic.
That’s why an integrated approach is needed to understand and assess the importance of each kind of stressors and to define restoration strategies.
The research work carried out in the last three years and shown in this thesis concerns impaired river ecosystems and includes, in particular:
1) Integrated study of chemical, hydrological and biological aspects of impaired rivers, especially those affected by multiple alterations in urban environments and, thus, wastewater treatment plant effluent dominated. A case study (Lura stream) is presented.
2) Development of analytical methods for determining organic micropollutants (PAHs, triazines and their main transformation products) in a wide range of surface and wastewater samples (coming from different environments in Italy and Spain) and, consequently, for evaluating the contamination from wastewater treatment plant discharges.
3) Evaluation of the organic micropollutant removal efficiencies of wastewater treatment plants and comparison of the concentrations measured in effluent samples to the environmental quality objectives fixed for surface waters, as most of the receptor flow is made by the discharged effluent itself.
4) Study of the performance of a demonstration scale constructed wetland in removing inorganic and organic contamination from wastewater treatment plant effluents, as a possible strategy for impaired river restoration.
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McClurg, Sarah Elizabeth. « Stream ecosystem response to mitigative limestone treatment in acid impaired, central Appalachian streams ». Morgantown, W. Va. : [West Virginia University Libraries], 2004. https://etd.wvu.edu/etd/controller.jsp?moduleName=documentdata&jsp%5FetdId=3667.
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Thesis (M.S.)--West Virginia University, 2004.Title from document title page. Document formatted into pages; contains ix, 104 p. : ill., maps. Includes abstract. Includes bibliographical references (p. 41-49).
Livres sur le sujet "Impaired river"
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Pierce, Ron. A hierarchical strategy for prioritizing the restoration of 83 impaired tributaries of the Big Blackfoot River. Missoula, Mont : Montana Fish, Wildlife, and Parks, 2002.
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MapTech, Inc (Blacksburg Va ). Fecal bacteria and general standard total maximum daily load development for impaired streams in the Middle River and Upper South River watersheds, Augusta County, VA. Richmond, Va.] : Dept. of Environmental Quality, 2004.
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Memphis Oral School for the Deaf et Innovo Publishing (Firm), dir. Rivers' walk. 2010.
Trouver le texte intégralChapitres de livres sur le sujet "Impaired river"
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Marcé, Rafael, Jordi Honey-Rosés, Andreu Manzano, Lucas Moragas, Bernardette Catllar et Sergi Sabater. « The Llobregat River Basin : A Paradigm of Impaired Rivers Under Climate Change Threats ». Dans The Handbook of Environmental Chemistry, 1–26. Berlin, Heidelberg : Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/698_2012_152.
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« Strategies for Restoring River Ecosystems : Sources of Variability and Uncertainty in Natural and Managed Systems ». Dans Strategies for Restoring River Ecosystems : Sources of Variability and Uncertainty in Natural and Managed Systems, sous la direction de F. R. HAUER, C. N. DAHM, G. A. LAMBERTI et J. A. STANFORD. American Fisheries Society, 2003. http://dx.doi.org/10.47886/9781888569469.ch4.
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<em>Abstract</em>.—River ecosystem integrity is evaluated within a variety of landscape scales. We examine influences of variations in natural processes and human actions on river ecosystems and propose a concept for restoring impaired systems. The ecological structure and function of rivers vary across a hierarchy of landscape scales with different spatial and temporal dimensions. The major linkages within river systems include exchange of water and materials along longitudinal connections from streams to rivers, lateral connections between river and floodplain systems, and vertical surface and subsurface (hyporheic) water exchanges. Strong longitudinal linkages dominate confined river reaches while unconfined floodplain reaches show strong affinities for lateral and vertical exchange. A landscape concept, “the shifting habitat mosaic” (SHM), provides a framework for understanding how these interactions create and maintain the physical and ecological diversity of habitats, biotic communities, and ecosystem integrity. While each river system has unique physical and ecological characteristics, many human actions and ecological effects can be expressed within the SHM concept. For example, societal needs for power generation, transportation, water management, and land uses (e.g., urban and agricultural) often alter natural processes of hydrologic regimes and material transport and deposition. These factors affect interactions between the river channel and the surrounding river–riparian corridor. Restoration strategies can apply the SHM concept by focusing on restoring normative variations to processes (e.g., hydrologic regimes) that contribute to ecosystem integrity. Management practices (e.g., dam hydrologic regimes, flood control facilities, levees, land uses) can be modified to restore natural physical and ecological processes (e.g., thermal regimes, water exchange, and animal migrations).
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Otis, Jessica J. « Other Support Services ». Dans Aniridia and WAGR Syndrome. Oxford University Press, 2010. http://dx.doi.org/10.1093/oso/9780195389302.003.0017.
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Besides the support of Aniridia Foundation International, there are several other services for the blind and visually impaired. Parent Training and Information Centers and Community Parent Resource Centers can help parents with children who are blind or visually impaired. These centers are located all over the United States, and they help families of children and young adults with disabilities (from birth to age 22). Also, they help families obtain appropriate education and services for their children with disabilities, train and inform parents and professionals on a variety of topics, resolve problems between families and schools, and connect children with disabilities to community resources that address their needs. For more information on a center located in your state, please visit http://www.ilru.org/html/publications/directory/index.html. All websites mentioned in this chapter will be listed at the end of this chapter along with several other websites for other services and organizations that may assist you. The Lighthouse International has been helping visually impaired people since 1905. It strives to help visually impaired individuals live better lives and to be in independent. It is also dedicated to preventing disabilities. To accomplish this it has research studies, prevention efforts, advocacy initiatives, education programs, and vision rehabilitation services. For more information, please visit the Lighthouse International website at www.lighthouse.org. The Lions International began to dedicate services to the visually impaired in 1925 when Helen Keller challenged the Lions Club to be “knights of the blind in the crusade against darkness.” Today Lions is successful in helping those who are blind and visually impaired. A very important program Lions has is called SightFirst. This program was started in 1989 to help prevent blindness. Just a few of the services are helping to construct or expand eye hospitals and clinics, contributing to cataract surgeries, and providing sight-saving medication. This program is also striving to eliminate preventable childhood blindness, and to control river blindness and trachoma. For more information, please visit the Lions International website at www.lionsclubs.org.
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M. Tarekegn, Mekonnen, et Getaneh L. Weldekidan. « Concentration Levels of Heavy Metals and Selected Ions in the Irrigation Water : The Case of Little Akaki River, Addis Ababa, Ethiopia ». Dans Environmental Impact and Remediation of Heavy Metals [Working Title]. IntechOpen, 2022. http://dx.doi.org/10.5772/intechopen.103677.
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Irrigable water resources have been challenged by the contamination of heavy metals and unwanted ions that impair plant growth and human health. It impaired the quality of edible fruit & vegetables. The objective of this study was to determine the concentration of heavy metals (Pb, Cd, Cr, and Cu) and selected ions (chloride, Na, Mg, Ca), and to evaluate its suitability for irrigation use. Water samples were collected from three various locations (the upstream, middle stream, and downstream) of the river. Temperature (T), EC, pH, and total dissolved solids (TDS) were tested onsite using handheld multiparameter testing equipment, while the heavy metals (Pb, Cd, Cr, and Cu) and selected ions (Chloride, Na, Mg, and Ca) of the water sample were analyzed using (ICP-OES). ANOVA test was conducted to examine the concentration variations of heavy metals and selected ions between the sampling locations along the river. The concentrations of (Pb and Cd) were found (2.5–3.9), (0.03–0.4) mg/L respectively, and (Cr and Cu) were below the detectible limit of the (ICP-OES) equipment. Cadmium (Cd) was found to be higher than the permissible limit of FAO (0.01mg/L) for irrigation water. There was no significant variation of heavy metals and selected ions between the sampling locations.
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Ridgway, J., K. Cave, A. DeMaria, J. O’Meara et J. H. Hartig. « Cost-and ecosystem-effective restoration of impaired beneficial uses in the Rouge River Ar of Concern, Michigan ». Dans Ecosystem-Based Management of Laurentian Great Lakes Areas of Concern, 211–34. Michigan State University Press, 2021. http://dx.doi.org/10.14321/j.ctv1z7kkd4.13.
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Levy, Sharon. « The Fight This Time ». Dans The Marsh Builders. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780190246402.003.0018.
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Forty- five years after the passage of the Clean Water Act (CWA), water pollution remains a profound problem. More than forty- seven thousand US waters are impaired. At the rate these lakes, rivers, and estuaries are being cleaned up, it will take more than five hundred years to make them all safe for swimming and fishing. Oliver Houck, a professor of law at Tulane University who has focused on environmental protection since the 1970s, sums up the situation: “We have not had clean water in America,” he writes, “in the lifetime of anyone living.” The major source of pollution in the waters of the US, as in other developed countries, is now runoff from farm fields and city streets. These nonpoint sources remain difficult to control. More than 75 percent of the rivers and lakes that fail to meet water quality standards are tainted by nonpoint sources. In terms of nutrient pollution, agricultural runoff is by far the dominant source, triggering harmful algal blooms from Chesapeake Bay to Puget Sound. The CWA of 1972 addressed point sources of pollution in a decisive and radical way. Section 402 of the CWA applies effluent standards based on the best available treatment technology to city sewage and industrial wastewaters, and puts regulatory power in the hands of the federal Environmental Protection Agency (EPA). Regulation under this scheme has brought dramatic improvement in water quality. Before the CWA was enacted, major urban river systems throughout the country had such low levels of dissolved oxygen that fish kills became routine, and urban beaches were often closed due to fecal contamination. By the late 1990s, dissolved oxygen levels had improved in about 70 percent of river reaches and watersheds studied by the EPA, and fish had returned to many waters. Beach closures decreased. Problems remain, especially in cities like Chicago and Baltimore, where heavy rains can overwhelm treatment systems, releasing raw sewage downstream. Still, in terms of curbing point source pollution, the CWA has made a critical difference. The rise of pollution from unregulated nonpoint sources has eaten away at these water quality gains. The Mississippi River basin, whose waters flow into the northern Gulf of Mexico, may be the most dramatic example. In August 2017, the Gulf’s dead zone grew to an unprecedented 8,776 square miles, about the size of New Jersey.
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« Fishery Resources, Environment, and Conservation in the Mississippi and Yangtze (Changjiang) River Basins ». Dans Fishery Resources, Environment, and Conservation in the Mississippi and Yangtze (Changjiang) River Basins, sous la direction de Yushun Chen, Mike Daniels, Michele Reba, Jennifer Bouldin, Chris Henry, Pearl Daniel, Sagar Shrestha et al. American Fisheries Society, 2016. http://dx.doi.org/10.47886/9781934874448.ch14.
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<em>Abstract</em>.—Agriculture has been identified as a potential leading source of nutrients (nitrogen and phosphorus) and sediment enrichment of water bodies within the Mississippi River basin (MRB) and contributes to impaired water quality and biological resources in the MRB and the northern Gulf of Mexico (GOM). This study reviewed agriculture, impacts on water quality and biological resources, and a brief introduction of watershed conservation programs in the MRB. Agriculture has increased nutrients and sediment loads to the Mississippi River and the northern GOM since the 1950s. Fish and macroinvertebrate communities have shifted, and low oxygen and high-turbidity-tolerant groups became dominant. In addition to existing conservation practices such as the Conservation Reserve Program through the 1985 farm bill and other related programs (e.g., the Wetlands Reserve Program), a recent basin-wide conservation initiative—the Mississippi River Basin Healthy Watersheds Initiative (MRBI)—was launched by U.S. Department of Agriculture Natural Resources Conservation Service in 2010. The MRBI provides financial incentives (more than US$222 million) to producers and landowners in 640 watersheds of 13 states to implement voluntary conservation practices that improve water quality, restore wetlands, enhance wildlife habitat, and sustain agricultural profitability. Edge-of-field and watershed monitoring have been initiated through the MRBI and related agricultural conservation programs such as Section 319 of the U.S. Environmental Protection Agency Clean Water Act and new initiatives such as the Discovery Farms program in Arkansas, Wisconsin, Minnesota, and North Dakota, Pioneer Farm in Wisconsin, the Louisiana Master Farmer Program in Louisiana, and others in the MRB states. These efforts will greatly improve downstream watershed ecosystem health by avoiding, controlling, and trapping nutrient and sediment runoff from agricultural fields to the Mississippi River and GOM. Although there continues to be problems with nutrient transport, sedimentation, and depleted groundwater supplies, agriculture will likely have less influence on the future ecological health condition of the Mississippi River and GOM. Future restoration programs need to focus more on state or regional coordination by classifying restoration projects and standardizing the geographic scale and evaluation methods across the whole MRB.
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Loomisa, John, Paula Kentb, Liz Strangec, Kurt Fauschc et Alan Covichc. « Measuring the total economic value of restoring ecosystem services in an impaired river basin : results from a contingent valuation survey ». Dans Economics of Water Resources, 77–91. Routledge, 2018. http://dx.doi.org/10.4324/9781351159289-6.
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« Early Life Stage Mortality Syndrome in Fishes of the Great Lakes and Baltic Sea ». Dans Early Life Stage Mortality Syndrome in Fishes of the Great Lakes and Baltic Sea, sous la direction de Gun Åkerman et Lennart Balk. American Fisheries Society, 1998. http://dx.doi.org/10.47886/9781888569087.ch6.
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<em>Abstract</em>.—The reproductive success of cod <em>Gadus morhua </em>from the Baltic Sea and the Barents Sea was compared. The offspring of 17 family pairs from the Baltic Sea and 12 family pairs from the Barents Sea were investigated during the embryonic and larval development stages. Frequencies of mortality over time and frequencies of different disorders at hatch were analyzed. The results indicated that the reproductive success of cod from the Baltic Sea was seriously impaired. The Baltic cod showed high mortality before hatch. In newly hatched larvae, different kinds of disorders were seen, such as vertebrae deformity, disrupted yolk sac or subcutaneous edema in the yolk sac, and precipitate in the yolk. To compare mortality and early developmental abnormalities in Baltic cod and Baltic salmon <em>Salmo salar</em>, the offspring of 20 salmon family pairs, caught in the River Dalälven in Sweden, were investigated analogically. The results showed that the majority of the salmon offspring experienced a thiamine deficiency-dependent mortality at different stages of larval development and that five family pairs experienced high mortality before hatch. In salmon, different kinds of disorders were also seen at hatch, such as vertebrae deformity, blood disorders, subcutaneous edema in the yolk sac, and precipitate in the yolk. The disorders at hatch were not correlated to later thiamine deficiency-dependent mortality. Aliquots of newly fertilized salmon eggs were injected with thiamine by the nanoinjection method. This treatment had only a minor effect on the frequency of disorders at hatch, but it protected the salmon larvae almost completely from later thiamine deficiency-dependent mortality. This indicates that factors other than thiamine deficiency are involved in the developmental disorders. In both salmon and cod from the Baltic Sea, the mortality and disorders among the offspring were mainly correlated to the female, and in both species some females produced offspring that experienced high mortality before hatch. Both salmon and cod also showed disorders that might have similar biochemical mechanisms, because the formation of precipitates and edema in the yolk sac occurs in both species.
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« Balancing Fisheries Management and Water Uses for Impounded River Systems ». Dans Balancing Fisheries Management and Water Uses for Impounded River Systems, sous la direction de John J. Ney et John P. Ney. American Fisheries Society, 2008. http://dx.doi.org/10.47886/9781934874066.ch36.
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<em>Abstract</em>.—The number of advisories issued to limit consumption of contaminated freshwater fishes has grown exponentially in the United States in the past decade. More than 80% of extant fish consumption advisories (FCAs) are for mercury and polychlorinated biphenyls, both of which can impair fetal and early childhood development; women of child-bearing age and children constitute the most sensitive consumer group, and the most restrictive advisories target them. Most FCAs are issued by state health departments, with fisheries management agencies in supplementary roles. We conducted a literature review and interviewed public health and fisheries management personnel in six states to evaluate the interstate consistency of FCAs, methods and content of risk communication, and the effectiveness of these efforts in generating public awareness and influencing angler behavior. Fish consumption limits are largely based on risk assessment inputs from the U.S. Environmental Protection Agency and U.S. Food and Drug Administration; the former are more conservative. States may employ risk management to balance socioeconomic costs versus health benefits in setting consumption limits. Among states in our sample, contaminant concentrations that triggered issuance of FCAs varied by an order of magnitude, and the consumption limits were frequently complex. Consumption advisories are communicated to the public by Web site, press release, brochures, signage, and personal contact; anglers are also informed in their fishing regulations. Despite these efforts, awareness of FCAs by the general public are as low as 20–40%, even for the targeted women’s group. The awareness level among licensed anglers as reported in several surveys exceeded 50%, but compliance with the advised consumption limits was often much lower. Conversely, the fraction of risk-averse anglers who have ceased fishing entirely is unknown. Poor awareness and acceptance of FCAs may be due to the perception that health risks from fish consumption are low, as well as from the volume and complexity of the FCAs themselves. States should consider revision of their FCAs for consistency and simplicity and to communicate the probabilities of adverse health effects as a result of fish consumption relative to other foods and common behaviors. Fisheries management agencies can assume more active roles by communicating relative risks to anglers and by adopting strategies to reduce the availability of contaminated sport fish for harvest and consumption.
Actes de conférences sur le sujet "Impaired river"
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Tota-Maharaj, Kiran. « Evaluating the Performance of Low-Energy Feed Forward Osmosis System for Desalination using Impaired and Saline Water Sources ». Dans Environmental Engineering. VGTU Technika, 2017. http://dx.doi.org/10.3846/enviro.2017.091.
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Forward Osmosis (FO) is a natural process of treating water or wastewater due to the difference in osmotic pres-sures. FO is a membrane separation technology, applicable to food processing, industrial wastewater treatment and seawater or brackish water desalination. The phenomena of FO processes occur whereby water molecules are driven across a semi-permeable membrane by an osmotic pressure gradient that is generated from a higher concentrate draw solution. FO processes can recover potable water resources from wastewater streams through the flow of pure water from a lower concentrated feed solution towards higher concentrated draw solutions leaving behind pollutants, impurities, and salts in the semi-permeable membrane. This paper assesses the design, build and testing of a laboratory scaled Feed Forward Osmosis (FFO) system for treating river water collected from the River Medway, Kent, England. The FO process was a highly effective form of river water treatment and able to treat the River Water with high rejection rates of solutes (>90%). Experimental results showed that the FFO system can achieve a better performance when the molarity of the draw solution is higher. The average solute rejection rate of the FO membrane for both inorganic and organic compounds was 94.83 %. Moreover, the operation of the forward osmosis membrane illustrated that it has a lower fouling propensity and higher solute rejection capabilities. The pilot scaled FFO system has the ability for greater salt rejection and lower electronic conductivity levels which resulted from the successful desalination of river water. A sodium chloride (NaCl) or saltwater draw solution performed positively in inducing higher os-motic pressures with a substantial effect of lower energy requirements for the system. Lower energy consumptions of the FFO system allow similar water treatment possibilities with energy savings potential. The FFO system showed to be an environ-mentally viable and economically feasible river water treatment technology.
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Gene Yagow et Robert N. Brent. « North River : Case Study of a Category 4 TMDL - "Impaired, but TMDL not needed" ». Dans 2006 Portland, Oregon, July 9-12, 2006. St. Joseph, MI : American Society of Agricultural and Biological Engineers, 2006. http://dx.doi.org/10.13031/2013.21021.
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Baldissera, Adriana Diniz. « Evolução urbana e recursos hídricos : uma leitura do papel dos cursos d’água no desenvolvimento de Chapecó-SC ». Dans Seminario Internacional de Investigación en Urbanismo. Barcelona : Instituto de Arte Americano. Universidad de Buenos Aires, 2013. http://dx.doi.org/10.5821/siiu.5884.
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Chapecó caracteriza-se como pólo agroindustrial do sul do Brasil e centro econômico, político e cultural do oeste do Estado de Santa Catarina. Com extensão de 624,30 Km² e população de 183.561 habitantes, situa-se em sítio geográfico marcado pela abundancia de recursos hídricos: localiza-se sobre a área de abrangência do Aquífero Guarani, na margem direita do Rio Uruguai. A área urbana do município distribui-se por duas microbacias, que apresentam diferentes graus de comprometimento hídrico. A disponibilidade de água, em quantidade e qualidade, tem sido uma condicionante ao desenvolvimento urbano nos diferentes ciclos econômicos, caracterizando uma relação de exploração, na maioria das vezes, de destruição de seus recursos naturais. Este trabalho evidencia a relação histórica do município de Chapecó com seus cursos d’água, sua contribuição na construção do espaço municipal e possibilidades de qualificação desta relação no presente, especialmente na Microbacia do Lajeado São José, que ainda apresenta muitas características naturais. Chapecó is characterized as agribusiness hub of southern Brazil; economic, political and cultural center of western region of Santa Catarina, composed by 624.30 km² and 183,561 inhabitants, located in a geographical area marked by abundance of water resources, the city is situated on the coverage area of “Guarani Aquifer”, on the right margin of “Uruguay River”. The urban area is spread over two watersheds, which have varying degrees of impaired water. Water availability in quantity and quality has been a constraint to urban development in different economic cycles, featuring an exploitative relationship, most often, the destruction of its natural resources. This work shows the historical relationship of the city with its watercourses, the contribution in the construction of municipal space and possibilities of qualification in this respect, especially in Basin “Lajeado São Jose”, which yet has many natural features.
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Smith, Kent Leland, Laura J. Crossey, Chris McGibbon et Jon K. Golla. « USING STABLE ISOTOPES AND CONTINUOUS SENSORS TO TRACK GEOTHERMAL SALINITY CONTRIBUTIONS THAT IMPAIR SURFACE AND GROUNDWATER QUALITY, JEMEZ RIVER, NM ». Dans Joint 70th Annual Rocky Mountain GSA Section / 114th Annual Cordilleran GSA Section Meeting - 2018. Geological Society of America, 2018. http://dx.doi.org/10.1130/abs/2018rm-314271.
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