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871.
Gerzabek MH Barceló D Bellin A Rijnaarts HH Slob A Darmendrail D Fowler HJ Négrel P Frank E Grathwohl P Kuntz D Barth JA 《Journal of environmental management》2007,84(2):237-243
The integrated project "AquaTerra" with the full title "integrated modeling of the river-sediment-soil-groundwater system; advanced tools for the management of catchment areas and river basins in the context of global change" is among the first environmental projects within the sixth Framework Program of the European Union. Commencing in June 2004, it brought together a multidisciplinary team of 45 partner organizations from 12 EU countries, Romania, Switzerland, Serbia and Montenegro. AquaTerra is an ambitious project with the primary objective of laying the foundations for a better understanding of the behavior of environmental pollutants and their fluxes in the soil-sediment-water system with respect to climate and land use changes. The project performs research as well as modeling on river-sediment-soil-groundwater systems through quantification of deposition, sorption and turnover rates and the development of numerical models to reveal fluxes and trends in soil and sediment functioning. Scales ranging from the laboratory to river basins are addressed with the potential to provide improved river basin management, enhanced soil and groundwater monitoring as well as the early identification and forecasting of impacts on water quantity and quality. Study areas are the catchments of the Ebro, Meuse, Elbe and Danube Rivers and the Brévilles Spring. Here we outline the general structure of the project and the activities conducted within eleven existing sub-projects of AquaTerra. 相似文献
872.
Waste materials for activated carbon preparation and its use in aqueous-phase treatment: a review 总被引:6,自引:0,他引:6
Dias JM Alvim-Ferraz MC Almeida MF Rivera-Utrilla J Sánchez-Polo M 《Journal of environmental management》2007,85(4):833-846
Commercial activated carbon is a preferred adsorbent for the removal of micropollutants from the aqueous phase; however, its widespread use is restricted due to high associated costs. To decrease treatment costs, attempts have been made to find inexpensive alternative activated carbon (AC) precursors, such as waste materials. Some reviews report the use of waste materials for the preparation of AC; however, these studies are restricted to either type of wastes, preparation procedures, or specific aqueous-phase applications. The present work reviews and evaluates literature dedicated both to the preparation of AC by recycling different types of waste materials and also to its application in various aqueous-phase treatments. It is clear that conventional (from agriculture and wood industry) and non-conventional (from municipal and industrial activities) wastes can be used to prepare AC, that can be applied in various aqueous treatment processes, namely to remove organic pollutants, dyes, volatile organic compounds, and heavy metals. Moreover, high surface areas can be obtained using either physical or chemical activation; however, combined treatments might enhance the surface properties of the adsorbent, therefore increasing its adsorption capacity. It is evident from the revision made that AC prepared from both conventional and non-conventional wastes might effectively compete with the commercial ones. This happens mostly when the activation procedures are optimized considering both the raw material used to produce the carbons and the contaminants to be removed. 相似文献
873.
We sampled 240 wadeable streams across Wisconsin for different forms of phosphorus and nitrogen, and assemblages of macroinvertebrates
and fish to (1) examine how macroinvertebrate and fish measures correlated with the nutrients; (2) quantify relationships
between key biological measures and nutrient forms to identify potential threshold levels of nutrients to support nutrient
criteria development; and (3) evaluate the importance of nutrients in influencing biological assemblages relative to other
physicochemical factors at different spatial scales. Twenty-three of the 35 fish and 18 of the 26 macroinvertebrate measures
significantly correlated (P < 0.05) with at least one nutrient measure. Percentages of carnivorous, intolerant, and omnivorous fishes, index of biotic
integrity, and salmonid abundance were fish measures correlated with the most nutrient measures and had the highest correlation
coefficients. Percentages of Ephemeroptera–Plecoptera–Trichoptera individuals and taxa, Hilsenhoff biotic index, and mean
tolerance value were macroinvertebrate measures that most strongly correlated with the most nutrient measures. Selected biological
measures showed clear trends toward degradation as concentrations of phosphorus and nitrogen increased, and some measures
showed clear thresholds where biological measures changed drastically with small changes in nutrient concentrations. Our selected
environmental factors explained 54% of the variation in the fish assemblages. Of this explained variance, 46% was attributed
to catchment and instream habitat, 15% to nutrients, 3% to other water quality measures, and 36% to the interactions among
all the environmental variables. Selected environmental factors explained 53% of the variation in macroinvertebrate assemblages.
Of this explained variance, 42% was attributed to catchment and instream habitat, 22% to nutrients, 5% to other water quality
measures, and 32% to the interactions among all the environmental variables. 相似文献
874.
The Patagonian coast is considered a relatively pristine environment. However, studies conducted along coastal Patagonia have
showed hydrocarbon pollution mostly concentrated at ports that have fishing, oil loading, general merchant, and/or tourist
activities. A high value of total aliphatic hydrocarbons (TAH) was found at the Rawson fishing port (741 μg/g dw). In other
ports with and without petroleum-related activities, hydrocarbon values were approximately 100 μg/g dw. The highest values
for TAH and total aromatic hydrocarbons (TArH) were found in Faro Aristizábal, north of San Jorge gulf (1304 and 737 μg/g
dw, respectively). This is very likely the result of petroleum-related activities at the Comodoro Rivadavia, Caleta Cordova,
and Caleta Olivia ports located within this gulf. In other coastal areas away from potential anthropogenic sources, hydrocarbon
values were less than 2 and 3 μg/g dw for TAH and TArH, respectively. This review of published and unpublished information
suggests that ports are important oil pollution sources in the Patagonian coast. More detailed studies are needed to evaluate
the area affected by port activities, to understand the mechanisms of hydrocarbon distribution in surrounding environments,
and to assess bioaccumulation in marine organisms. Despite that some regulations exist to control oil pollution derived from
port and docked vessel activities, new and stricter management guidelines should be implemented. 相似文献
875.
Raymond Philippe Paul Sylvianne Perron André Bellehumeur Christian Larocque Émilie Charest Hugues 《Food and environmental virology》2022,14(1):40-58
Food and Environmental Virology - Human noroviruses are among the main causes of acute gastroenteritis worldwide. Frozen raspberries have been linked to several norovirus food-related outbreaks.... 相似文献
876.
Geology has been highlighted by a number of authors as a key factor in high indoor radon levels. In the light of this, this study examines the application of seasonal correction factors to indoor radon concentrations in the UK. This practice is based on an extensive database gathered by the National Radiological Protection Board over the years (small-scale surveys began in 1976 and continued with a larger scale survey in 1988) and reflects well known seasonal variations observed in indoor radon levels. However, due to the complexity of underlying geology (the UK arguably has the world's most complex solid and surficial geology over the shortest distances) and considerable variations in permeability of underlying materials it is clear that there are a significant number of occurrences where the application of a seasonal correction factor may give rise to over-estimated or under-estimated radon levels. Therefore, the practice of applying a seasonal correction should be one that is undertaken with caution, or not at all. This work is based on case studies taken from the Northamptonshire region and comparisons made to other permeable geologies in the UK. 相似文献
877.
Nicolas Lamouroux Hervé Pella Ton H. Snelder Eric Sauquet Jérome Lejot Ude Shankar 《Journal of the American Water Resources Association》2014,50(1):1-13
Spatially comprehensive estimates of the physical characteristics of river segments over large areas are required in many large‐scale analyses of river systems and for the management of multiple basins. Remote sensing and modeling are often used to estimate river characteristics over large areas, but the uncertainties associated with these estimates and their dependence on the physical characteristics of the segments and their catchments are seldom quantified. Using test data with varying degrees of independence, we derived analytical models of the uncertainty associated with estimates of upstream catchment area (CA), segment slope, and mean annual discharge for all river segments of a digital representation of the hydrographic network of France. Although there were strong relationships between our test data and estimates at the scale of France, there were also large relative local uncertainties, which varied with the physical characteristics of the segments and their catchments. Discharge and CA were relatively uncertain where discharge was low and catchments were small. Discharge uncertainty also increased in catchments with large rainfall events and low minimum temperature. The uncertainty of segment slope was strongly related to segment length. Our uncertainty models were consistent across large regions of France, suggesting some degree of generality. Their analytical formulation should facilitate their use in large‐scale ecological studies and simulation models. 相似文献
878.
879.
Different water Acts (e.g., the European Water Framework Directive) and stakeholders involved in aquatic affairs have promoted integrated river basin management over recent decades. However, few studies have provided feedback on these policies. The aim of the current article is to fill this gap by exploring how local newspapers reflect the implementation of a broad public participation within a catchment of France known for its innovation with regard to this domain. The media coverage of a water management strategy in the Drôme watershed from 1981 to 2008 was investigated using a content analysis and a geographic information system. We sought to determine what public participation and decentralized decision-making can be in practice. The results showed that this policy was integrated because of its social perspective, the high number of involved stakeholders, the willingness to handle water issues, and the local scale suitable for participation. We emphasized the prominence of the watershed scale guaranteed by the local water authority. This area was also characterized by compromise, arrangements, and power dynamics on a fine scale. We examined the most politically engaged writings regarding water management, which topics of each group emphasized, and how the groups agreed and disagreed on issues based on their values and context. The temporal pattern of participation implementation was progressive but worked by fits and starts. 相似文献
880.
Melanie D. Harrison Andrew J. Miller Peter M. Groffman Paul M. Mayer Sujay S. Kaushal 《Journal of the American Water Resources Association》2014,50(6):1365-1382
Although wetlands are known to be sinks for nitrogen (N) and phosphorus (P), their function in urban watersheds remains unclear. We analyzed water and nitrate (NO3?) and phosphate (PO43?) dynamics during precipitation events in two oxbow wetlands that were created during geomorphic stream restoration in Baltimore County, Maryland that varied in the nature and extent of connectivity to the adjacent stream. Oxbow 1 (Ox1) received 1.6‐4.2% and Oxbow 2 (Ox2) received 4.2‐7.4% of cumulative streamflow during storm events from subsurface seepage (Ox1) and surface flow (Ox2). The retention time of incoming stormwater ranged from 0.2 to 6.7 days in Ox1 and 1.8 to 4.3 days in Ox2. Retention rates in the wetlands ranged from 0.25 to 2.74 g N/m2/day in Ox1 and 0.29 to 1.94 g N/m2/day in Ox2. Percent retention of the NO3?‐N load that entered the wetlands during the storm events ranged from 64 to 87% and 23 to 26%, in Ox1 and Ox2, respectively. During all four storm events, Ox1 and Ox2 were a small net source of dissolved PO43? to the adjacent stream (i.e., more P exited than entered the wetland), releasing P at a rate of 0.23‐20.83 mg P/m2/day and 3.43‐24.84 mg P/m2/day, respectively. N and P removal efficiency of the oxbows were regulated by hydrologic connectivity, hydraulic loading, and retention time. Incidental oxbow wetlands have potential to receive urban stream and storm flow and to be significant N sinks, but they may be sources of P in urban watersheds. 相似文献