Search results for "feature"
showing 10 items of 4091 documents
Receiving water body quality assessment: an integrated mathematical approach applied to an Italian case study
2011
This study presents a basin-scale approach to the analysis of receiving water body quality considering both point and non-point pollution sources. In particular, this paper describes an extensive data gathering campaign carried out in the Nocella catchment, which is an agricultural and semi-urbanised basin located in Sicily, Italy. Two sewer systems, two wastewater treatment plants and a river reach were monitored during both dry and wet weather periods. A mathematical model of the entire integrated system was also created. Specifically, a detailed modelling approach was developed by employing three well known models: Storm Water Management Model, GPS-X and Soil and Water Assessment Tool. T…
Bioavailability and assessment of heavy metal pollution in sediment cores off the Mejerda River Delta (Gulf of Tunis): How useful is a multiproxy app…
2016
International audience; Three core samples were taken from zones offshore from the Mejerda River Delta (Tunisia) and analyzed formajor and trace elements to assess their relationships with organic matter, monosulfides and carbonates, aswell as for pollution and bioavailability. Chemical speciation,ΣSEM/AVS, the enrichment factor (EF) and thegeo-accumulation index (I-geo) were used. Iron, cadmium, lead and zinc – the most frequently mined metalsin the Mejerda catchment – were found as contaminants in the offshore areas. Estimations of trace elementaccumulation using the EF and the I-geo index show that lead, and to a lesser extent zinc, are the most pollutingmetals off the Mejerda outlet. Ac…
Assessing drugs of abuse distribution in Turia River based on geographic information system and liquid chromatography mass spectrometry
2017
Drugs of abuse are continuously discharged into wastewaters as part of their elimination process. Pollution at very low concentrations appears to be broad in environmental compartments near populated areas. A total of 42 drugs of abuse and metabolites were analysed in surface water samples collected in 2012 and 2013 by solid phase extraction and liquid chromatography coupled to mass spectrometry. Analytical results of target compounds were georeferenced and integrated into a geographical information systems (GIS). Ecotoxicological risk of drugs of abuse detected in the Turia River was evaluated in this study by calculating risk quotient (RQ). In 2012, 6 compounds were detected in a total of…
Occurrence, distribution and behavior of emerging persistent organic pollutants (POPs) in a Mediterranean wetland protected area.
2018
The analysis of perfluoroalkyl substances (PFASs) and organophosphate flame retardants (PFRs) in the different environmental compartments of a characteristic coastal wetland, the Albufera Natural Park (Valencia, Spain), is required for understanding the transport, accumulation and fate of these pollutants in an area under high anthropogenic pressure. Samples included 13 wastewater treatment plant influents, 13 effluents, 12 surface water, 19 sediment samples and 10 fish individuals from the Albufera Natural Park and the surrounding area. Tris(2-chloroisopropyl) phosphate (TCIPP) and perfluorooctane sulfonate (PFOS) were at the highest concentrations in water, 330.2 ng L−1 and 47.8 ng L−1, r…
Heavy metals in urban soils: a case study from the city of Palermo (Sicily), Italy.
2002
Concentrations of V, Mn, Cd, Zn, Ni, Cr, Co, Cu, Pb, Hg and Sb were measured on 70 topsoil samples collected from green areas and parks in the city of Palermo (Sicily) in order to: (1) assess the distribution of these heavy metals in the urban environment; (2) discriminate natural and anthropic contributions; and (3) identify possible sources of pollution. Mineralogy, physico-chemical parameters, and major element contents of the topsoils were determined to highlight the influence of 'natural' features on the heavy metal concentrations and their distribution. Medians of Pb, Zn, Cu and Hg concentrations of the investigated urban soils are 202, 138, 63 and 0.68 mgkg(-1), respectively. These v…
Blackfly Larvae (Simulium spp.) Can Intensify Methylmercury Biomagnification in Boreal Food Webs
2020
AbstractGlobal pollution of mercury (Hg) threatens ecosystem and human health. We measured total Hg (THg) and monomethylmercury (MMHg) concentrations in filter-feeding blackfly (Simulium spp.) larvae in the inflows and the outflows of six boreal lakes with no Hg point source pollution. THg in the larvae ranged from 0.03 to 0.31 mg kg−1 dw and MMHg between 0.02 and 0.25 mg kg−1 dw. The proportion of MMHg in the larvae was 74 ± 0.16% and ranged from 43 to 98% of THg, the highest proportions being comparable to those typically found in aquatic predatory insects and fish. We compared the larvae MMHg concentrations to river water quality, catchment land-use, and to size-adjusted lake pike THg da…
Transcriptomic, biochemical and individual markers in transplanted Daphnia magna to characterize impacts in the field
2015
Daphnia magna individuals were transplanted across 12 sites from three Spanish river basins (Llobregat, Ebro, Jucar) showing different sources of pollution. Gene transcription, feeding and biochemical responses in the field were assessed and compared with those obtained in re-constituted water treatments spiked with organic eluates obtained from water samples collected at the same locations and sampling periods. Up to 166 trace contaminants were detected in water and classified by their mode of action into 45 groups that included metals, pharmaceuticals, pesticides, illicit drugs, and other industrial compounds. Physicochemical water parameters differentiated the three river basins with Llo…
Pollution of Flooded Arable Soils with Heavy Metals and Polycyclic Aromatic Hydrocarbons (PAHs)
2014
Soils that are exposed to floodwaters because of shallow groundwater and periodical wetlands are, to a large extent, exposed to contamination by organic and inorganic compounds. These are mainly compounds that have drifted along with the inflow of heavily laden floodwater and are produced within the soil profile by the anaerobic transformation of organic matter. Heavy metals and polycyclic aromatic hydrocarbon (PAH) compounds are absorbed by the soil of the floodwaters, and moving in the soil profile, they pose a threat to groundwater. What is more, after a flood, they may be absorbed by the crops. This paper focuses on the effects of Odra River (Poland) floods, heavy metals, and PAHs on so…
Short-term low-severity spring grassland fire impacts on soil extractable elements and soil ratios in Lithuania
2017
Abstract Spring grassland fires are common in boreal areas as a consequence of slash and burn agriculture used to remove dry grass to increase soil nutrient properties and crop production. However, few works have investigated fire impacts on these grassland ecosystems, especially in the immediate period after the fire. The objective of this work was to study the short-term impacts of a spring grassland fire in Lithuania. Four days after the fire we established a 400 m2 sampling grid within the burned area and in an adjacent unburned area with the same topographical, hydrological and pedological characteristics. We collected topsoil samples immediately after the fire (0 months), 2, 5, 7 and …
Total mercury and methyl-mercury contents and accumulation in polar microbial mats.
2014
Although polar regions are considered isolated and pristine areas, the organisms that inhabit these zones are exposed to global pollution. Heavy metals, such as mercury, are global pollutants and can reach almost any location on Earth. Mercury may come from natural, volcanic or geological sources, or result from anthropogenic sources, in particular industrial or mining activities. In this study, we have investigated one of the most prominent biological non-marine communities in both polar regions, microbial mats, in terms of their Hg and methyl-mercury (MeHg) concentrations and accumulation capacities. The main hypotheses posed argued on the importance of different factors, and to test them…