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1.
Chemosphere ; 240: 124879, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31568947

RESUMO

Heavy metals which pollute aquatic environments typically bond with bottom sediments and the analysis of the spatial distribution of metals allows to assess the geochemical purity of deposits and to identify the potential pollution sources. Research carried out on the Wigry Lake involved the collection of almost 500 samples of sediments, and the specification of the depth of their residence (0.2-71.4 m) as well as the level of concentration of three metals: Fe (80.3-32 857 mg kg-1), Mn (17.8-1698 mg kg-1) and Zn (3.14-632 mg kg-1). The geochemical and bathymetric data was interpolated using geostatistical methods and mapped with the consideration of 5 types of sediments: lacustrine chalk, carbonate gyttja, fluvial-lacustrine sediment, organic gyttja and clastic sediment. As a result, a significant increase in the concentration of metals was revealed in deeper zones, at a considerable distance from the lake shore, wherein the respective values of correlation coefficients were as follows: depth-Mn 0.77; depth-Fe 0.60; depth-Zn 0.58. A strong dependency between the concentration of analysed metals and the type of sediment, attributed to the granular and chemical composition of sediments, was also revealed. Correlations between individual metallic pairs (Fe-Mn 0.77; Fe-Zn 0.80; Mn-Zn 0.75) indicated that similar factors influence spatial distribution of metals in sediments. The implementation of 3 different geochemical backgrounds allowed to conclude that the Wigry Lake is slightly polluted with the analysed metals, and that the origin of Mn is mainly natural, while in the case of Fe and Zn anthropogenic influence can also be identified.


Assuntos
Monitoramento Ambiental/métodos , Sedimentos Geológicos/análise , Lagos/química , Metais Pesados/análise , Poluentes Químicos da Água/análise , Polônia
2.
Chemosphere ; 238: 124610, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31450112

RESUMO

Antifouling paint particles (APPs) are residues generated primarily during maintenance of vessels and marine structures, and usually occur in boat maintenance areas that are adjacent to aquatic environments, such as estuaries. APPs end up in sediment layers after their release into aquatic systems and represent a threat to benthic invertebrates, which have different habitat and feeding modes. Thus, the aim of the present study was to evaluate the toxicity of APPs-spiked sediment to the benthic microcrustaceans Monokalliapseudes schubarti (a tanaid) and Hyalella azteca (an amphipod), testing whole sediment and elutriate solutions under estuarine conditions. Whole sediment spiked with APPs was more toxic to these organisms than the elutriate solution. This toxicity was attributed to the high concentrations of Cu and Zn metals quantified in the APPs. During the whole sediment test, M. schubarti was more sensitive than H. azteca. M. schubarti is an infauna organism, and its interaction with sediments (e.g. by ingestion of sediment particles) makes it more susceptible to compounds released from APPs than H. azteca, which tends to interact with these compounds at the sediment-water interface. In addition, in tests with sediment elutriate and without sediment, M. schubarti was not affected, while elutriate with 1.50% APPs showed to be significantly toxic to H. azteca. Moreover, these results indicate that APPs act as continuous and localized sources of metals to benthic organisms, highlighting the importance of better APP management and disposal practices in boat maintenance areas to avoid local aquatic contamination.


Assuntos
Anfípodes/efeitos dos fármacos , Crustáceos/efeitos dos fármacos , Sedimentos Geológicos/análise , Pintura/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Incrustação Biológica/prevenção & controle
3.
Chemosphere ; 239: 124748, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31520971

RESUMO

A total of 100 samples were collected from the sediments of a typical copper mining area, south China. Leaching concentrations of selected heavy metals (Ni, Cd, Cu, Pb, Zn, Ba, As, and Hg) were measured to evaluate their distribution patterns and associated health risk. Leaching concentrations of Cu (3.58 ±â€¯1.49 mg/L), Pb (1.50 ±â€¯1.06 mg/L), and Zn (4.04 ±â€¯1.68 mg/L) were significantly higher than the other metals in the samples. By evaluating the spatial heterogeneity, it was found that leaching metal concentrations did not decrease with environmental gradients, mostly caused by diverse distribution in pollution sources. The hazard index and carcinogenic risk indices showed significant risks of human exposure. For public safety, priority governance should be given to the main pollutants (Cd, Cu, Pb, Zn, and As) in sediments. In future studies, the integrated data will be urgently required for local stakeholders to conduct environmental monitoring and remediation scenarios.


Assuntos
Sedimentos Geológicos/análise , Metais Pesados/análise , Mineração , Poluentes do Solo/análise , Poluentes Químicos da Água/toxicidade , Carcinógenos/toxicidade , China , Cobre , Exposição Ambiental/efeitos adversos , Monitoramento Ambiental , Humanos , Metais Pesados/toxicidade , Modelos Teóricos , Saúde Pública , Medição de Risco , Poluentes do Solo/toxicidade , Poluentes Químicos da Água/análise
4.
Chemosphere ; 239: 124773, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31518919

RESUMO

Hyporheic zone (HZ) sediments in river systems are often contaminated with heavy metals as a legacy of natural processes and anthropogenic activities. The geochemical behaviors of heavy metals in the HZ sediments at the laboratory scale have been extensively studied. However, the watershed-scale distributions of heavy metals in the HZ sediments and the processes controlling their distributions have not been well studied. Here, we report a watershed-scale study of heavy metals (i.e., Cr, Ni, Cu, Zn, Cd, and Pb) distributions in the HZ of the Maozhou River watershed, a heavily polluted area within the Pearl River Delta, southern China. Statistical analysis revealed that the spatial distribution of studied heavy metal concentrations was highly correlated with that of the sediment-associated sulfide at the watershed-scale. Metal extraction analysis and double-spherical aberration-corrected scanning transmission electron microscope imaging (Cs-STEM) further confirmed the strong association of heavy metals with sulfur. These observations demonstrated that the formation of metals-sulfide precipitates was the key process controlling the watershed-scale distributions of heavy metals (especially for Cr, Ni and Zn) in the HZ sediments. Additionally, high permeability of the HZ sediments may prevent Ni, Zn, Cd and Pb accumulation in sediments. Specially, Cu distribution was mainly affected by organic-Cu complexation. In the estuary area, salinity input likely affected the distributions of Ni, Zn and Cd through cation exchange processes. The findings improved our understanding of the distributions of heavy metals and the processes controlling their distributions at the watershed-scale, and have implications for remediating and managing contaminated HZ sediments.


Assuntos
Sedimentos Geológicos/análise , Metais Pesados/análise , Poluentes Químicos da Água/análise , China , Monitoramento Ambiental/métodos , Estuários , Sedimentos Geológicos/química , Metais Pesados/química , Metais Pesados/isolamento & purificação , Microscopia Eletrônica de Transmissão e Varredura , Rios , Salinidade , Sulfetos/análise , Sulfetos/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação
5.
Chemosphere ; 239: 124767, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31518925

RESUMO

The present study analyzed the Peruvian scallop Argopecten purpuratus and its food sources for metal and fatty acid concentrations in order to determine spatial and temporal differences. Metals such as copper (Cu), manganese (Mn), and zinc (Zn) in gills and iron (Fe) and Zn in sediments were the most significant explaining factors for spatial differentiations (degree of contamination), while for fatty acids, it was C14:0, C15:0, C16:0 and C18:0 in A. purpuratus' muscle and in its food sources, which explained more temporal differences (El Niño-Southern Oscillation (ENSO) effect). Gills, digestive gland and intestine were the tissues where metal accumulation was the highest in A. purpuratus. Cd in digestive gland was always high, up to ∼250-fold higher than in other tissues, as previously reported in other bioindicator species for metal pollution. Fatty acids were good biomarkers when annual comparisons were performed, while metals when locations were compared. ENSO 2017 played an important role to disentangle A. purpuratus' biological conditions and food sources. A. purpuratus from Paracas locations mostly showed higher metal concentrations in gills and digestive glands, and lower fatty acid concentrations in muscle than those from Sechura and Illescas Reserved Zone.


Assuntos
Monitoramento Ambiental/métodos , Sedimentos Geológicos/análise , Pectinidae/química , Poluentes Químicos da Água/análise , Animais , Aquicultura , Cobre/análise , Cobre/farmacocinética , Biomarcadores Ambientais , Ácidos Graxos/análise , Brânquias/química , Ferro/análise , Ferro/farmacocinética , Manganês/análise , Manganês/farmacocinética , Músculos/química , Pectinidae/metabolismo , Peru , Frutos do Mar/análise , Análise Espaço-Temporal , Distribuição Tecidual , Zinco/análise , Zinco/farmacocinética
6.
Chemosphere ; 239: 124720, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31499313

RESUMO

Cathodic protection by galvanic anodes (GACP) is often used to protect immerged metallic structures in harbor environments, especially GACP employing aluminum-based anodes. To follow a previous study that was performed in a laboratory on Al-anode, two monitoring periods were performed in parallel, one in an in situ environment (in the Port of Calais) for 42 months and the other in a laboratory for 18 months, to evaluate the transfer of metals constituting the Al-anode towards the sedimentary compartment. During each monitoring, two conditions of agitation of water (weak and strong) were compared, and different factors of sediment quality were used to assess the enrichment and potential toxic effects of these released metals. The results showed that the dissolution of Al-anode-induced a greater Zn enrichment of sediment than an Al enrichment. This is in contrast with the abundance of these elements present in the composition of the anode and suggested a potential toxic effect for marine organisms with regards to the discovered Zn level, especially in confined areas.


Assuntos
Alumínio , Eletrodos/efeitos adversos , Monitoramento Ambiental/métodos , Sedimentos Geológicos/análise , Organismos Aquáticos , Sedimentos Geológicos/química , Metais Pesados/análise , Poluentes Químicos da Água/análise , Zinco/análise , Zinco/toxicidade
7.
Chemosphere ; 239: 124729, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31526992

RESUMO

To our knowledge, this is the first study in Portugal for the analysis of both antibiotics and psychiatric drugs in river waters from Douro and Leça rivers and its sediments. Samples were extracted using solid phase extraction and QuEChERS procedures and the analysis was performed using liquid chromatography with tandem mass spectrometry. Higher number of pharmaceuticals and higher concentrations were found in the Leça river for the two matrices under study. The highest detection frequency for the twenty-seven pharmaceuticals was observed for fluoxetine with 83.3% in both matrices. None of the studied antibiotics were detected in water collected in the Douro river however six antibiotics (azithromycin, ciprofloxacin, clarithromycin, moxifloxacin, ofloxacin, and trimethoprim) were found in the Leça river. Further, the analysis of sediments exhibits the occurrence of sulfamethoxypyridazine in the Douro river and azithromycin in the Leça river. The highest concentration was observed in Leça river for azithromycin in the river water (2,819 ng/L) and sediments (43.2 ng/g). Carbamazepine, citalopram, fluoxetine, sertraline, trazodone, and venlafaxine were the psychiatric drugs detected in river waters and sediments with more diazepam as water river contamination. Concentrations ranged from

Assuntos
Antibacterianos/análise , Antidepressivos/análise , Sedimentos Geológicos/análise , Poluentes Químicos da Água/análise , Cromatografia Líquida , Monitoramento Ambiental/métodos , Limite de Detecção , Portugal , Rios/química , Extração em Fase Sólida , Espectrometria de Massas em Tandem
8.
Chemosphere ; 240: 124965, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31726610

RESUMO

To investigate the effects of spatial expansion between native invasive species (Phragmites australis) and commom native species (Cyperus malaccensis) on variations of micro-elements (Pb, Cr, Cu, Zn, Ni, Cd and As) in decomposing litters in the Min River estuary, in situ filed decomposition experiment was conducted in P. australis (PA) community (before expansion, BE), C. malaccensis (CM) community (before expansion, BE) and P. australis-C. malaccensis (PA'-CM') community (during expansion, DE) from February 2016 to February 2017 by space-for- time substitution method. Results showed that the decomposition of C. malaccensis were faster than those of P. australis whether at BE stage or at DE stage. The decomposition rate of PA' increased by 24.40% compared to PA whereas the value of CM' decreased by 15.67% compared with CM. The concentrations of Pb, Cu, Zn, Ni, Cd and As in decomposing litters of P. australis (PA and PA') and C. malaccensis (CM and CM') generally showed increasing tendency and the values in the former were significantly lower than those in the latter (p < 0.05). The physicochemical sorption onto recalcitrant organic fractions and the substrate quality (C/N and M/C ratios) of decomposing litters were two important factors affecting the differences in As/metals variations between species. The levels of Cr in decaying litters increased initially and decreased afterward, and the values in P. australis were significantly higher than those in C. malaccensis (p < 0.05). Whether at BE stage or at DE stage, stocks of As/metals in decomposing litters of P. australis (PA and PA') were generally higher than those of C. malaccensis (CM and CM'). The lower stocks of As/metals in CM or CM' might be more dependent on its lower mass remaining. Compared with PA at BE stage, the accumulation of As/metals in decomposing litters of PA' at DE stage decreased greatly, which might be ascribed to the lower precipitation of metal sulfides in PA'. Stocks of Zn, Ni, Cd and Cr in CM' and stocks of Cr in PA' generally evidenced the export of metals from decomposing litter to environment, indicating that the potential exposure risk of Zn, Ni, Cd and Cr might be increased as CM was invading by PA. This study found that the spatial expansion between P. australis and C. malaccensis not only altered the stocks of As/metals in decomposing litters but also increased the exposure risk of Zn, Ni, Cd and Cr in ecotone. In future, as the ecological functions of ecotone was precisely evaluated during the expansion of the two plants in the Min River estuary, the alterations of litter decomposition rates and the exposure risks of Zn, Ni and Cd caused by CM' should be emphasized.


Assuntos
Arsênico/análise , Cyperus/química , Monitoramento Ambiental/métodos , Estuários , Espécies Introduzidas , Metais Pesados/análise , Poaceae/química , China , Sedimentos Geológicos/análise , Sedimentos Geológicos/química , Rios/química , Poluentes Químicos da Água/análise
9.
Environ Monit Assess ; 191(12): 757, 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31741091

RESUMO

Landuse change significantly alters the hydrologic characteristics of the land surface within a watershed. In the present study, the impact of landuse change (2006-2016) on runoff and sediment yield has been assessed in Patiala-Ki-Rao watershed (5140 ha) located in Shivalik foot-hills, using remote sensing, geographical information system (GIS), and Water Erosion Prediction Project (WEPP) watershed model. The watershed has seven major landuse classes, namely agriculture, built-up, fallow land, forest, grass land, streams, and water bodies. The landuse change analysis indicated that the area under all the landuses decreased except built-up that increased by 372.27 ha (112.04%). Forest is the most affected landuse among all watershed landuses that shrinked by 194.90 ha followed by agriculture (64.57 ha), grass land (50.81 ha), streams (30.42 ha), fallow land (21.86 ha), and water bodies (9.72 ha). Runoff and sediment yield for the landuse of the years 2006 and 2016 were simulated by the WEPP model using two climate scenarios (2006 and 2016). The simulated runoff, sediment yield, and sediment delivery ratio increased by 18.62%, 48.04%, and 32.23% under Climate-2006 and 26.78%, 30.23%, and 16.09% under Climate-2016 due to change in landuse during a period of 10 years. This clearly indicates that landuse change in 10 years has greatly influenced the hydrology of the watershed and requires urgent land allocation policy in place for sustainable development in the area.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos/análise , Rios/química , Movimentos da Água , Agricultura , Clima , Hidrologia , Índia , Modelos Teóricos , Poaceae , Água
10.
Environ Monit Assess ; 191(11): 664, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31650234

RESUMO

Excessive delivery of fine sediment has been implicated as the main water quality stressor in the Tsitsa River catchment. This study evaluates the responses of the taxa Ephemeroptera, Plecoptera and Trichoptera (EPT) to suspended sediment and grain size distribution in eight selected study sites in the Tsitsa River catchment. The sampling of macroinvertebrates took place seasonally from August 2016 to April 2017 and EPT identified to either genus or species level. To avoid site redundancy, the sites were clustered into four groups, with groups 1 and 2 being more impacted when compared to groups 3 and 4. The results of the sediment grain size analysis revealed that sediment grain size distribution ranged from 0.121 to 5.61 µm; percent clay and percent silt were the most dominant sediment fractions across all groups. Among the EPT metrics examined, Shannon index, Simpson's index, evenness, Ephemeroptera abundance, EPT abundance and Trichoptera abundance were sensitive, differentiating between sediment groups 3 and 4 (less impacted groups) from 1 and 2 (highly impacted groups). Site groups 3 and 4 supported more EPT species, in terms of the number of individuals and diversity. Species such as Caenis sp., Pseudocloeon glaucum, Oligoneuropsis lawrencei and Baetis sp. were considered sediment-tolerant, displaying strong positive association with influenced groups. Taxa such as Hydropsyche sp., Pseudocloeon sp., Cheumatopsyche sp. and Afronurus sp. were considered sediment-sensitive. Overall, the present study revealed that genera/species within the order EPT were differentially sensitive to fine sediment stress and grain sizes, proving to be useful bioindicators.


Assuntos
Monitoramento Ambiental/métodos , Ephemeroptera/fisiologia , Sedimentos Geológicos/análise , Insetos/fisiologia , Qualidade da Água , Animais , Ecossistema , Rios/química , África do Sul
11.
Environ Monit Assess ; 191(11): 676, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31654216

RESUMO

In steep dry-tropical islands, rural and urban development can lead to accelerated soil erosion and the delivery of land-based materials into marine ecosystems. The objective of this paper was to compare stream water composition, clay minerology, and sediment yield between a partially urbanized (Coral Bay) and an undisturbed (Lameshur) coastal watersheds in St. John, US Virgin Islands (USVI). The saturation index of streamflow water samples was calculated using "The Geochemist's Workbench" software and most likely precipitated minerals from observed storm events was then compared with X-ray diffraction on soil clay mineralogy. The spatial distribution on both annual mean (2010) erosion rates and storm event-wise (Hurricane Otto) sediment yield among the two study watersheds were modeled using the revised and modified universal soil loss equations (RUSLE; MUSLE), respectively. Cations concentration in stream flow water samples and sediment yield were higher for the partially urbanized (Coral Bay) compared to the undisturbed (Lameshur) watershed. Our findings suggest that rural/urban development may increase stream water cations concentration and inputs of sediment to downstream ecosystems. Future studies evaluating the effect of management practices such as pavement or other stabilization of dirt roads and their impact on stream water quality and quantity and sediment yield are crucial for the proper sediment management in the study watersheds and potentially in other rural-urbanizing tropical watersheds.


Assuntos
Monitoramento Ambiental/métodos , Sedimentos Geológicos/análise , Solo/química , Reforma Urbana/estatística & dados numéricos , Urbanização , Animais , Antozoários , Ecossistema , Ilhas Virgens Americanas
12.
Environ Monit Assess ; 191(11): 655, 2019 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-31630261

RESUMO

Mining activities are important for the country's economy, but they cause serious threats to the environment. The geology of SW Turkey comprises Southern (Çine) Submassif of Menderes Metamorphic Massif and the Lycian Nappes. These geological units are unconformably overlain by lignite-bearing Miocene deposits, Upper Miocene-Pliocene conglomerates and Quaternary alluvial deposits. The aim of this study is to determine the geospatial change of mining activities in the Mugla-Aydin provinces, SW Turkey. For this purpose, Landsat-5 TM, Landsat-7 ETM, Landsat-8 OLI and Google Earth satellite image data for 1984, 1994, 2004, 2014 and 2018 have been used for change detection analysis. In 1984, only a Miocene lignite quarry was excavated. Then, in 1994, operations for the excavation of feldspar-quartz and marble quarries were started, and from 2004 to 2014, mining activities significantly accelerated. An aerial image of 2018 shows that an area of about 3800 ha has been exploited by mining at 149 quarries. Considering access roads to quarries, plants and dam reservoirs, the human impact extends over 3800 ha. The study area is home to several archaeological sites and endemic biota. Thus, there is an urgent need for the relocation and protection of archaeological heritages and endemic biota by creating special zones. Additionally, the rich geomorphologic features in the study area that require millions of years to form are at risk of totally disappearing.


Assuntos
Conservação dos Recursos Naturais/métodos , Monitoramento Ambiental/métodos , Sedimentos Geológicos/análise , Mineração , Imagens de Satélites , Carbonato de Cálcio/análise , Carvão Mineral/análise , Atividades Humanas , Turquia
13.
Mar Pollut Bull ; 145: 138-147, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31590769

RESUMO

To investigate the effects of the water-sediment regulation on the spatial variations of metals in the surface sediments of the Yellow River Estuary (YRE), sampling sites were set in 2015 (51 sites in June and 33 in October). The content of Cu, Pb, Cd, Cr, Zn, Ni and Mn was determined using inductively coupled plasma spectrometry and of Hg and As atomic fluorescence spectrometry. The results showed that the concentrations of metals in the sediments of YRE were lower after the regulation, while that of most metals increased in the tidal areas of the current estuary with fine particles. Environmental pollution and ecological risk of metals were mainly from Hg and Cd. Metals carried with the silt of the river should be focused. The findings were expected to update the current status of metal pollution of YRE and be helpful for the delicacy management of the regime and silt-laden rivers.


Assuntos
Arsênico/análise , Sedimentos Geológicos/análise , Metais Pesados/análise , Poluentes Químicos da Água/análise , Áreas Alagadas , China , Monitoramento Ambiental/métodos , Política Ambiental , Estuários , Sedimentos Geológicos/química , Rios/química
14.
Mar Pollut Bull ; 145: 208-213, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31590777

RESUMO

Mangroves connect terrestrial and marine ecosystems and are sensitive to environmental change, and the sediments within faithfully record long-term changes in the aquatic environment and supplement the generally short monitoring archives. Here we present a sediment-core record of TN, TP, TOC, and C/N ratios from the Futian mangrove wetland, Shenzhen Bay (South China), and compare with our remote sensing-derived land use change and the nearby seawater monitoring records. Our reconstructed record extends the history of tropic state change back to the Year 1958, supplementing the monitoring activity initiated in 1987. More importantly, the results reveal two distinct periods. The pre-1983 period (Year 1958-1982) is characterized by increased nutrient due to agricultural activities, while the post-1983 period (Year 1983-2014) is marked by reduced TP but relatively stable TN values, during which the simultaneous increase in construction lands and C/N ratios suggests enhanced soil erosion due to the rapid urbanization of Shenzhen City.


Assuntos
Carbono/análise , Sedimentos Geológicos/análise , Nitrogênio/análise , Fósforo/análise , Agricultura , Baías , China , Cidades , Ecossistema , Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Solo , Urbanização , Áreas Alagadas
15.
Mar Pollut Bull ; 145: 224-238, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31590780

RESUMO

Adverse impacts of drilling discharges on marine benthic environments have been observed since the advent of offshore drilling operations for exploration and production of oil and gas. This study utilizes a marine sediment model based on a system of equations that has been developed earlier to assess environmental impacts of drilling waste discharges. Bioturbation, bio-degradation and natural burial processes are included in the model. The model is based on the diagenetic equations, providing vertical concentration profiles of dissolved oxygen, naturally deposited substances and discharged substances in the marine sediment as a basis for marine risk assessment. The governing equations are solved by a random walk particle-tracking method for each constituent evaluated explicitly in time. The developed model is enhanced with a kernel smoothing method to obtain smooth concentration profiles. Simulation results reveal that the method demonstrates stable behavior for different model parameters, providing a promising alternative to finite difference approaches.


Assuntos
Sedimentos Geológicos/química , Modelos Teóricos , Indústria de Petróleo e Gás , Meio Ambiente , Sedimentos Geológicos/análise , Distribuição Aleatória , Medição de Risco/métodos
16.
Mar Pollut Bull ; 145: 248-253, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31590783

RESUMO

In a Daya Bay 120-year dated sediment core(1892-2010), analyses were conducted of grain-size, water content, TOC, TIC, TC, loss on ignition, TN, BSi and TP, to reconstruct the anthropogenic activity history. The entire core was divided into four periods. Multi-parametric measurements, their ratios and interrelations are seen to clearly reflect the development of agriculture, aquaculture, industry and social economy surrounding Daya Bay. The trends of TOC, TOM and BSi after 1990 may be due to mass input of nutritious matter from aquaculture and industry, whereas the trends of BSi, TOC and TOM between 1960 and 1990 were owing to aquaculture and agriculture. Two peaks of BSi, TOC and TOM in 1994 and 2002 imply that the mass input of cooling water from nuclear power plants may be a significant contributor to ecological environment changes. Finally, some proposals were put forward for the healthy and sustainable development of Daya Bay.


Assuntos
Carbono/análise , Sedimentos Geológicos/análise , Sedimentos Geológicos/química , Aquicultura , Baías , China , Meio Ambiente , Monitoramento Ambiental , Nitrogênio/análise , Centrais Nucleares , Dióxido de Silício/análise
17.
Mar Pollut Bull ; 145: 5-13, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31590817

RESUMO

The objective of the present study was to test whether the Atlantic ghost crab Ocypode quadrata is a reliable biomonitor of microplastic (MP) pollution of beach sediments. To test the hypothesis (H1) that the sediment is the main source of MP ingestion, the proportion of MP types (hard plastic, microfibers, pellet, soft plastic, and extruded polystyrene foam) in the gut content was compared with that on the strandline. The types of MPs in the gut content and sediment had similar proportions; black (~49%) and blue (~45%) microfibers were responsible for this similarity (55%), hence confirming H1. However, the second hypothesis (H2) that prevalence of MP in the gut content is related to its density on beach with distinct urbanization degree was not accepted. These results indicate that high trophic plasticity of the ghost crab and, consequently, multiple-sources of contamination may interfere with its use as a biomonitor of MP pollution.


Assuntos
Braquiúros/crescimento & desenvolvimento , Sedimentos Geológicos/análise , Poluentes da Água/análise , Animais , Praias , Braquiúros/efeitos dos fármacos , Braquiúros/metabolismo , Monitoramento Ambiental/métodos , Plásticos/análise , Plásticos/farmacologia , Urbanização , Poluentes da Água/farmacologia
18.
Mar Pollut Bull ; 145: 526-535, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31590820

RESUMO

Sediments are important hosts for metals and such should be incorporated in aquatic environment monitoring programs. In the present study, the concentrations of metals, multiple geochemical indices and guidelines along with multivariate statistical analysis were applied to identify the accumulation, sources and pollution levels of metals in the surface sediment. The mean metal concentrations in the sediments were ranked as follows: Fe > Cr > Ni > V > Zn > Cu > Pb > Cd. Based on the geo-accumulation index and multiple pollution indices the overall pattern of environmental quality status of the khouran Straits were uncontaminated to slightly polluted. Pearson correlation matrix combined with multivariate principal component analysis and cluster analysis suggest that Cd and Pb originated from anthropogenic sources, whereas Fe, Cu, Zn, Ni, V and Cr mostly originated both from natural processes and human activities with predominant anthropogenic influence in the investigated ecosystem.


Assuntos
Sedimentos Geológicos/análise , Metais/análise , Poluentes Químicos da Água/análise , Ecossistema , Monitoramento Ambiental , Sedimentos Geológicos/química , Oceano Índico , Análise Multivariada , Medição de Risco
19.
Mar Pollut Bull ; 145: 555-563, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31590823

RESUMO

The Nerbioi-Ibaizabal estuary (Bilbao, Basque Country) suffered an important input of contaminants, including metals and metalloids, between 1875 and 1975. We collected sediments in the tidal part of the river in January 2018 and measured the concentrations of 27 elements in them. At that time, two important construction works were taking place in the area: the extension of the commercial port and the opening of long semi-closed channel. Comparing the current metallic hotspots with the geographical distribution of elements in previous years (2009, 2010 and 2014) showed us that these works seem to have significantly influenced the distribution of toxic elements in the estuary, even if the critical point of the second one is still to arrive with the inundation of the connection to the mainland. Long term pollution monitoring reveals as a powerful tool to check the effects of ongoing engineering works in estuarine environments.


Assuntos
Sedimentos Geológicos/análise , Metaloides/análise , Metais/análise , Poluentes Químicos da Água/análise , Engenharia , Monitoramento Ambiental , Estuários , Limite de Detecção , Rios , Espanha
20.
Mar Pollut Bull ; 145: 569-582, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31590826

RESUMO

Microplastics (<5 mm) are ubiquitous in the marine environment, occurring in both sediments and surface waters worldwide. However, few studies have documented the presence of microplastics and tire wear particles in coastal rivers. A survey of microplastics and low-density tire wear particles (≥63 µm) in the sediment and surface water of the three major tributaries within the Charleston Harbor estuary was conducted. Intertidal sediment, subtidal sediment, and sea surface microlayer concentrations ranged from 0 to 652 microplastics/m2, 3-4,375 microplastics/kg wet weight, and 3-36 microplastics/L, respectively. Blue fibers and tire wear particles were the two most abundant microplastic types observed, constituting 26.2% and 17.1%, respectively, of total microplastics. Tire wear particles were primarily identified by morphology, and ATR-FTIR analysis was conducted for a small subset (n = 5) of larger particles (≥500 µm). The present study provides the first microplastic field assessment of low-density tire wear particles in estuarine tributaries.


Assuntos
/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Estuários , Sedimentos Geológicos/análise , Rios , South Carolina , Espectroscopia de Infravermelho com Transformada de Fourier , Instalações de Transporte , Poluentes Químicos da Água/química
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