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1.
Background, aim, and scope Water quality impairment by nutrient enrichment from agricultural activities has been a concern worldwide. Phytoremediation
technology using aquatic plants in constructed wetlands and stormwater detention ponds is increasingly applied to remediate
eutrophic waters. The objectives of this study were to evaluate the effectiveness and potential of water lettuce ( Pistia stratiotes L.) in removing nutrients including nitrogen (N) and phosphorus (P) from stormwater in the constructed water detention systems
before it is discharged into the St. Lucie Estuary, an important surface water system in Florida, using phytoremediation technologies. 相似文献
2.
Background, aim and scope Water quality impairment by heavy metal contamination is on the rise worldwide. Phytoremediation technology has been increasingly
applied to remediate wastewater and stormwater polluted by heavy metals. 相似文献
3.
Introduction Environmental heterogeneous methods were used for analysing data sets of trophic state with 11 parameters measured at 12 different
sites at Chaohu Lake for the period 2004 to 2006. The aim of this research was to determine spatial/temporal variations in
water quality, to assess trophic state and to identify pollution sources. Protective measures and schemes were proposed to
improve water quality in the lake. 相似文献
4.
Background, aim and scope This paper presents a preliminary study of the water profile with reference to microbiological parameters, required by Directive
2006/07/EC (European Community 2006) concerning the management of bathing water quality, in the coastal belt of the Province of Venice (Italy, Northern Adriatic
Sea). A historical database has been implemented with monitoring data for the period 2000–2006 (data on rivers, bathing and
marine coastal waters and on the characterization of Wastewater Treatment Plant (WWTP) discharges) from the institutional
activity of Veneto Regional Environmental Prevention and Protection Agency (ARPAV). An integrated areal analysis for the microbiological
investigation of homogeneous stretches along the coast of the Province of Venice was performed for a preliminary characterization
of the bathing water profile considering water quality status and existing pressure sources. 相似文献
5.
Background, aim, and scope The need for global and integrated approaches to water resources management, both from the quantitative and the qualitative
point of view, has long been recognized. Water quality management is a major issue for sustainable development and a mandatory
task with respect to the implementation of the European Water Framework Directive as well as the Swiss legislation. However,
data modelling to develop relational databases and subsequent geographic information system (GIS)-based water management instruments
are a rather recent and not that widespread trend. The publication of overall guidelines for data modelling along with the
EU Water Framework Directive is an important milestone in this area. Improving overall water quality requires better and more
easily accessible data, but also the possibility to link data to simulation models. Models are to be used to derive indicators
that will in turn support decision-making processes. For this whole chain to become effective at a river basin scale, all
its components have to become part of the current daily practice of the local water administration. Any system, tool, or instrument
that is not designed to meet, first of all, the fundamental needs of its primary end-users has almost no chance to be successful
in the longer term. 相似文献
6.
Introduction In order to evaluate water quality of a canal system, the spatial pattern of protozoan communities in response to physicochemical
variables was studied in the Hangzhou section of the Grand Canal, northern China during a 1-year cycle (February 2008–January
2009). 相似文献
7.
Bioretention, also known as rain garden, allows stormwater to soak into the ground through a soil-based medium, leading to removal of particulate and dissolved pollutants and reduced peak flows. Although soil organic matter (SOM) is efficient at sorbing many pollutants, amending the bioretention medium with highly effective adsorbents has been proposed to optimize pollutant removal and extend bioretention lifetime. The aim of this research was to investigate whether soil amended with activated carbon produced from sewage sludge increases the efficiency to remove hydrophobic organic compounds frequently detected in stormwater, compared to non-amended soil. Three lab-scale columns (520 cm3) were packed with soil (bulk density 1.22 g/cm3); activated carbon (0.5% w/w) was added to two of the columns. During 28 days, synthetic stormwater—ultrapure water spiked with seven hydrophobic organic pollutants and dissolved organic matter in the form of humic acids—was passed through the column beds using upward flow (45 mm/h). Pollutant concentrations in effluent water (collected every 12 h) and polluted soils, as well as desorbed amounts of pollutants from soils were determined using GC-MS. Compared to SOM, the activated carbon exhibited a significantly higher adsorption capacity for tested pollutants. The amended soil was most efficient for removing moderately hydrophobic compounds (log K
ow 4.0–4.4): as little as 0.5% (w/w), carbon addition may extend bioretention medium lifetime by approximately 10–20 years before saturation of these pollutants occurs. The column tests also indicated that released SOM sorb onto activated carbon, which may lead to early saturation of sorption sites on the carbon surface. The desorption test revealed that the pollutants are generally strongly sorbed to the soil particles, indicating low bioavailability and limited biodegradation. 相似文献
8.
Background, aim, and scope Alqueva Reservoir is the biggest artificial freshwater reservoir in Europe and is an important water supply for human and
agricultural consumption in the Alentejo region (Portugal). Pollution can impair environmental and human health status, and
to assure water quality and ecological balance, it is crucial to frequently monitor water supplies. In this study, we used
an ecotoxicological test battery to identify the potential toxicity of water from this reservoir. 相似文献
9.
Purpose The aim of this paper was to develop a new recreational water quality index (RWQI) as a tool to ensure the health of swimmers and to take practical decisions. Methods RWQI was elaborated with epidemiological data, and we carried out an exhaustive study of the different guidelines for recreational waters proposed by different organisations around the world. Different parameters were chosen, considering, as a priority, the swimmer??s contact and the possibility of ingestion of water during the recreational activity. Furthermore, rating curves were established for pH, chemical oxygen demand, nitrate, phosphate, detergents, enterococci, total coliforms, faecal coliforms and Escherichia coli. Results and conclusions The index was applied to the data set on water quality of the Potrero de los Funes River (San Luis, Argentina), generated during 2 years (2009?C2010). Following the RWQI values classification, most of the Potrero de los Funes water samples fell in the good quality range during the study period. 相似文献
10.
Background, aim, and scope The occurrence and fate of pharmaceuticals in the aquatic environment is recognized as one of the emerging issues in environmental
chemistry and as a matter of public concern. Existing data tend to focus on the concentrations of pharmaceuticals in the aqueous
phase, with limited studies on their concentrations in particulate phase such as sediments. Furthermore, current water quality
monitoring does not differentiate between soluble and colloidal phases in water samples, hindering our understanding of the
bioavailability and bioaccumulation of pharmaceuticals in aquatic organisms. In this study, an investigation was conducted
into the concentrations and phase association (soluble, colloidal, suspended particulate matter or SPM) of selected pharmaceuticals
(propranolol, sulfamethoxazole, meberverine, thioridazine, carbamazepine, tamoxifen, indomethacine, diclofenac, and meclofenamic
acid) in river water, effluents from sewage treatment works (STW), and groundwater in the UK. 相似文献
11.
Purposes and aims Economically efficient methods for removing arsenic from the drinking water supply are urgently needed in many parts of the
world. Iron oxides are known to have a strong affinity for arsenic in water. However, they are commonly present in the forms
of fine powder or floc, which limits their utility in water treatment. In this study, a novel granular adsorbent, iron-oxide-coated
diatomite (IOCD), was developed and examined for its adsorption of arsenic from water. 相似文献
12.
Purpose Nonpoint sources (NPS) pollution has been an important cause for water quality impairment worldwide. To take the temporal
variations of both NPS pollution and in-stream attenuation into consideration, an inverse modeling approach and the load duration
curve (LDC) method were combined for variable nutrient total maximum daily load (TMDL) development. 相似文献
13.
Purpose To protect the environmental quality of soil, groundwater, and surface water near the landfill site, it is necessary to make
an accurate assessment of the heavy metal mobility. This study aims to present the bio-immobilization behavior of heavy metals
in landfill and provide some reference suggestion for the manipulation of heavy metal pollution control after closure. 相似文献
14.
Purpose A conceptual model to assess water quality in river basins was developed here. The model was based on ecological risk assessment
principles, and incorporated a novel ranking and scoring system, based on self-organizing maps, to account for the likely
ecological hazards posed by the presence of chemical substances in freshwater. This approach was used to study the chemical
pollution in the Ebro River basin (Spain), whose currently applied environmental indices must be revised in terms of scientific
accuracy. 相似文献
15.
Aim of the study Helophytes like rush and reed are increasingly used for phytoremediation of contaminated water. This study characterises the
response of rush and reed plants to chemical stressors such as chlorobenzene, benzene and methyl- tert-butyl ether. The extractable wax layer of the cuticle was chosen for detailed investigations due to its multiple, particularly,
protective functions for plants and its easy availability for analysis. 相似文献
16.
Background, aim, and scope High-quality waters are steadily retreating worldwide. Discharge of industrial effluent in the environment again declines
soil/water quality to a great extent. On the other hand, effluent reuse in agriculture could be a means to conserve natural
resources by providing assured water supply for growing crops. But industrial effluents are highly variable in nature, containing
a variety of substances, and all are not favorable for farming. Appraisal and developing modes of effluent reuse is therefore
a prerequisite to enable its proper use in agriculture. Effluents of various industries were assessed and approaches for their
use in farming were developed for a particular region in this study. As per availability of effluents, the same could be implemented
in other water-scarce areas. 相似文献
17.
Background, aim, and scopeThe need for global and integrated approaches to water resources management, both from the quantitative and the qualitative point of view, has long been recognized. Water quality management is a major issue for sustainable development and a mandatory task with respect to the implementation of the European Water Framework Directive as well as the Swiss legislation. However, data modelling to develop relational databases and subsequent geographic information system (GIS)-based water management instruments are a rather recent and not that widespread trend. The publication of overall guidelines for data modelling along with the EU Water Framework Directive is an important milestone in this area. Improving overall water quality requires better and more easily accessible data, but also the possibility to link data to simulation models. Models are to be used to derive indicators that will in turn support decision-making processes. For this whole chain to become effective at a river basin scale, all its components have to become part of the current daily practice of the local water administration. Any system, tool, or instrument that is not designed to meet, first of all, the fundamental needs of its primary end-users has almost no chance to be successful in the longer term.Materials and methodsAlthough based on a pre-existing water resources management system developed in Switzerland, the methodological approach applied to develop a GIS-based water quality management system adapted to the Romanian context followed a set of well-defined steps: the first and very important step is the assessment of needs (on the basis of a careful analysis of the various activities and missions of the water administration and other relevant stakeholders in water management related issues). On that basis, a conceptual data model (CDM) can be developed, to be later on turned into a physical database. Finally, the specifically requested additional functionalities (i.e. functionalities not provided by classical commercial GIS software), also identified during the assessment of needs, are developed. This methodology was applied, on an experimental basin, in the Ialomita River basin.ResultsThe results obtained from this action-research project consist of a set of tangible elements, among which (1) a conceptual data model adapted to the Romanian specificities regarding water resources management (needs, data availability, etc.), (2) a related spatial relational database (objects and attributes in tables, links, etc.), that can be used to store the data collected, among others, by the water administration, and later on exploited with geographical information systems, (3) a toolbar (in the ESRI environment) offering the requested data processing and visualizing functionalities. Lessons learned from this whole process can be considered as additional, although less tangible, results.DiscussionThe applied methodology is fairly classical and did not come up with revolutionary results. Actually, the interesting aspects of this work are, on the one hand, and obviously, the fact that it produced tools matching the needs of the local (if not national) water administration (i.e. with a good chance of being effectively used in the day-to-day practice), and, on the other hand, the adaptations and adjustments that were needed both at the staff level and in technical terms.ConclusionsThis research showed that a GIS-based water management system needs to be backed by some basic data management tools that form the necessary support upon which a GIS can be deployed. The main lesson gained is that technology transfer has to pay much attention to the differences in existing situations and backgrounds in general, and therefore must be able to show much flexibility. The fact that the original objectives could be adapted to meet the real needs of the local end-users is considered as a major aspect in achieving a successful adaptation and development of water resources management tools. Time needed to setup things in real life was probably the most underestimated aspect in this technology transfer process.Recommendations and perspectivesThe whole material produced (conceptual data model, database and GIS tools) was disseminated among all river basin authorities in Romania on the behalf of the national water administration (ANAR). The fact that further developments, for example, to address water quantity issues more precisely, as envisaged by ANAR, can be seen as an indication that this project succeeded in providing an appropriate input to improve water quality in Romania on the long term. 相似文献
18.
Background Environmental agencies have to take measures to either reduce discharges and emissions of nitrate or to remediate nitrate-polluted
water bodies where the nitrate concentrations exceed threshold values. Isotope data can support the identification of nitrate
pollution sources and natural attenuation processes of nitrate. 相似文献
19.
Introduction From December 2008 to November 2009, an investigation of water quality was performed in the 70-km long downstream from Gezhouba Dam in Yangtze River. Methods Twelve sites in all were chosen. Nine parameters of water quality including the total phosphorus, the total nitrogen, chlorophyll a (Chl.a), nitrite, nitrate, ammonia, water temperature, DO, and pH were monitored almost monthly. The multivariate statistical technique (cluster analysis) and the nonparametric method (Kruskal?CWallis Test and Spearman??s rank correlation) were applied to evaluate the spatiotemporal variations of water quality data sets. Results and discussion According to the Chinese environmental quality standards for surface water (GB3838-2002), the water quality in the river section investigated can attain to the III water standards except total nitrogen. Further analysis indicated that there were no significant spatial differences in these parameters of water quality, but the sampling date had a significant effect. The temporal variation of water quality can be related to the discharge of Gezhouba Dam and moreover be affected by the reservoir regulation. During the discharge, the discharge increased the concentration of total phosphorus and then decreased the N:P ratio, which helps to the occurrence of algae blooms. The high consternation of phosphorus and the low N:P ratio show that the water body can be in the process of eutrophication during the discharge of Gezhouba Dam. In fact, Chl.a had begun to rise in the same period. 相似文献
20.
Introduction Water contamination is a notable environmental problem of the Niger Delta, Nigeria. The present work is an improved attempt
at a scientific discourse of water-quality issues in the Niger Delta of Nigeria with respect to heavy metal levels in surface
water in view of the hitherto dearth of scientific data. 相似文献
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