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1.
Chemosphere ; 313: 137281, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36410497

RESUMO

Discrepancies in rainfall chemistry in Bellsund were found to be influenced by the orographic barrier and related to the variability in the inflow of air masses as well as to the distance of sampling sites from the sea and thus the extent of sea spray impact. This study covers measurements of rainfall (P) and air temperature (T), physicochemical parameters (pH, specific electrolytic conductivity (SEC), major ions (Cl-, NO3-, SO42-) and elements (Na, Ca, Mg,K), as well as trace elements (i.a. As, Cd, Cr, Fe, Co, Pb, Ni, Zn) and dissolved organic carbon (DOC) in 22 rainfall samples collected in August on the Calypsostranda marine terrace and in the forefield of a land-terminating glacier (NW Wedel Jarlsberg Land). The comparison of chemical parameters in the samples revealed major discrepancies, including statistically significant higher rainwater pH and SEC, and the levels of Ag, As, Bi, Ca, Co, Fe, Li, Mn, Mo, Ni, Pb, Sb, and V, deposited near the seashore (Calypsostranda) than in the glacier forefield. Cluster analysis (CA) showed that elements deposited in lower concentrations at the glacier forefield site came from predominately anthropogenic sources. Conversely, CA results of metals and metalloids deposited on the Calypsostranda marine terrace indicate both natural and anthropogenic sources. A correlation matrix and principal component analysis (PCA) permitted identifying two primary factors affecting rainfall chemistry at each of the study sites. In Calypsostranda, these were the inflow of relatively unpolluted cold air (F1 = 35.1%) and sea spray (F2 = 27.6%), while in the glacier forefield the factors were an orographic barrier (F1 = 37.3%) and the inflow of polluted warm air (F2 = 25.2%).


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Oligoelementos , Svalbard , Chumbo/análise , Poluição do Ar/análise , Lítio/análise , Monitoramento Ambiental/métodos , Oligoelementos/análise , Poluentes Atmosféricos/análise
2.
Sci Total Environ ; 829: 154588, 2022 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-35306070

RESUMO

Despite growing access to precipitation time series records at a high temporal scale, in hydrology, and particularly urban hydrology, engineers still design and model drainage systems using scenarios of rainfall temporal distributions predefined by means of model hyetographs. This creates the need for the availability of credible statistical methods for the development and verification of already locally applied model hyetographs. The methodology development for identification of similar rainfall models is also important from the point of view of systems controlling stormwater runoff structure in real time, particularly those based on artificial intelligence. This paper presents a complete methodology of division of storm rainfalls sets into rainfalls clusters with similar temporal distributions, allowing for the final identification of local model hyetographs clusters. The methodology is based on cluster analysis, including the hierarchical agglomeration method and k-means clustering. The innovativeness of the postulated methodology involves: the objectivization of clusters determination number based on the analysis of total within sum of squares (wss) and the Calinski and Harabasz Index (CHIndex), verification of the internal coherence and external isolation of clusters based on the bootmean parameter, and the designated clusters profiling. The methodology is demonstrated at a scale of a large urban precipitation field of Kraków city on a total set of 1806 storm rainfalls from 25 rain gauges. The obtained results confirm the usefulness and repeatability of the developed methodology regarding storm rainfall clusters division, and identification of model hyetographs in particular clusters, at a scale of an entire city. The applied methodology can be successfully transferred on a global scale and applied in large urban agglomerations around the world.


Assuntos
Inteligência Artificial , Movimentos da Água , Cidades , Análise por Conglomerados , Hidrologia , Chuva
3.
Chemosphere ; 275: 130046, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33676272

RESUMO

Lake ecosystems are strongly coupled to features of their surrounding landscapes such as geomorphology, lithology, vegetation and hydrological characteristics. In the 2010-2018 summer seasons, we investigated an Arctic flow-through lake system Revvatnet, located in the vicinity of the coastal zone of Hornsund fjord in Svalbard, characterising its hydrological properties and the chemical composition of its waters. The lake system comprises of a small upper lake and a large lower one, the latter cone-shaped, with -29.1 m maximum depth. With near-neutral pH (full range 6.5-8.4) and low EC (7-147 µS cm-1), the lake has rather similar characteristics to many Arctic lakes. Metal and metalloid concentrations were either similar across the lake system or increased downstream (except Zn, which has important ore-bearing veins in the upper part of the catchment), which is consistent with the likely slow dissolution of suspended particles within the lakes. The ∑PAHs concentrations ranged from

Assuntos
Lagos , Poluentes Químicos da Água , Regiões Árticas , Ecossistema , Monitoramento Ambiental , Svalbard , Poluentes Químicos da Água/análise
5.
Sci Total Environ ; 653: 1571-1584, 2019 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-30545665

RESUMO

The Arctic hosts a set of unique ecosystems, characterised by extreme environmental conditions and undergoing a rapid change resulting from the average temperature rising. We present a study on an aquatic ecosystem of the Revelva catchment (Spitsbergen), based on samples collected from the lake, river and their tributaries, in the summer of 2016. The landscape variety of the study site and the seasonal change in the hydrological regime modify the availability of nutrients. In general, the upper part of the catchment consists of the mountain rocky slopes which are especially abundant in iron minerals, sulphides and phosphorus minerals. The lower part of the catchment is covered by plants - lichens, saxifrages and bryophytes, which are a different source of nutrients. In the analysed water samples, the maximum concentrations of nutrients such as iron, boron and phosphorus were 0.28 µg L-1, 4.52 µg L-1 and 1.91 µg L-1, respectively, in June, while in September, Fe and B reached the concentrations of 1.32 µg L-1 and 2.71 µg L-1, respectively. The concentration of P in September was below the detection limit of 1.00 µg L-1, which may be explained by the necessity of bacteria to consume it immediately on current needs. We noted also an increase in TOC concentration between the June and September samples, which could originate both from the biomass accumulation in the catchment and the permafrost melting contributing to the hydrological regime of the river. The bacterial community developed in this environment consisted mainly of Proteobacteria, Actinobacteria, Bacteroidetes and Firmicutes phylum, while the presence of Acidobacteria was less pronounced than in other tundra-related environments. The described catchment shows that despite the relatively small amount of bioavailable nutrients, the Revelva system is biodiverse and one of the most significant biogeochemical changes occurs there in response to seasonally switching water sources.


Assuntos
Amônia/análise , Bactérias/metabolismo , Microbiota/fisiologia , Nitratos/análise , Fosfatos/análise , Rios/microbiologia , Bactérias/classificação , Carbono/análise , Nutrientes/análise , Dinâmica Populacional , Estações do Ano , Svalbard , Tundra
6.
Ecol Evol ; 8(15): 7733-7739, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30151185

RESUMO

Environmental pollution, for example with metals, can significantly affect the ecosystem balance leading to severe changes. Biologically active pigments are relevant for the appearance and condition of birds. Melanin and carotenoid particles are the most frequently deposited pigments in avian integument. They are responsible for the majority of colors of bird plumage. The phenotypic expression can be affected by metal contamination. It can be manifested as color bleaching or differences in the size of plumage badges. In this study, we performed a comprehensive review of related studies in order to estimate the underlying population effect of this potential dependency. The study is based on the review of the literature regarding several avian species. It was designed to identify an area where the effect of the exposure is still poorly known. The analysis was specifically conducted to investigate the correlation between trace element concentration and eumelanin deposition. Moreover, we searched for factors that could affect spectral properties of feathers with carotenoid-based pigmentation. As a result, we found carotenoid-based pigmentation to be of a good use in terms of visual condition assessment. Changes in melanin-based pattern should be analyzed separately for eu- and pheomelanin as well as for a range of essential and toxic elements. Comprehensive studies on the subject are still scarce. Therefore, the issue requires further investigation.

7.
J Anal Methods Chem ; 2017: 7157953, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29348966

RESUMO

A simple and accurate ion chromatography (IC) method with pulsed amperometric detection (PAD) was proposed for the determination of cyanide ion in urine, sweat, and saliva samples. The sample pretreatment relies on alkaline digestion and application of Dionex OnGuard II H cartridge. Under the optimized conditions, the method showed good linearity in the range of 1-100 µg/L for urine, 5-100 µg/L for saliva, and 3-100 µg/L for sweat samples with determination coefficients (R) > 0.992. Low detection limits (LODs) in the range of 1.8 µg/L, 5.1 µg/L, and 5.8 µg/L for urine, saliva, and sweat samples, respectively, and good repeatability (CV < 3%, n = 3) were obtained. The proposed method has been successfully applied to the analysis of human biological samples.

8.
Microbes Environ ; 31(4): 401-409, 2016 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-27725345

RESUMO

Two thirds of Svalbard archipelago islands in the High Arctic are permanently covered with glacial ice and snow. Polar bacterial communities in the southern part of Svalbard were characterized using an amplicon sequencing approach. A total of 52,928 pyrosequencing reads were analyzed in order to reveal bacterial community structures in stream and lake surface water samples from the Fuglebekken and Revvatnet basins of southern Svalbard. Depending on the samples examined, bacterial communities at a higher taxonomic level mainly consisted either of Bacteroidetes, Betaproteobacteria, and Microgenomates (OP11) or Planctomycetes, Betaproteobacteria, and Bacteroidetes members, whereas a population of Microgenomates was prominent in 2 samples. At the lower taxonomic level, bacterial communities mostly comprised Microgenomates, Comamonadaceae, Flavobacteriaceae, Legionellales, SM2F11, Parcubacteria (OD1), and TM7 members at different proportions in each sample. The abundance of OTUs shared in common among samples was greater than 70%, with the exception of samples in which the proliferation of Planctomycetaceae, Phycisphaeraceae, and Candidatus Methylacidiphilum spp. lowered their relative abundance. A multi-variable analysis indicated that As, Pb, and Sb were the main environmental factors influencing bacterial profiles. We concluded that the bacterial communities in the polar aquatic ecosystems examined mainly consisted of freshwater and marine microorganisms involved in detritus mineralization, with a high proportion of zooplankton-associated taxa also being identified.


Assuntos
Bactérias/classificação , Bactérias/genética , Biota , Água Doce/microbiologia , Regiões Árticas , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Svalbard
9.
J Anal Methods Chem ; 2014: 769708, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24527257

RESUMO

Due to the specific structure of surfactants molecules they are applied in different areas of human activity (industry, household). After using and discharging from wastewater treatment plants as effluent stream, surface active agents (SAAs) are emitted to various elements of the environment (atmosphere, waters, and solid phases), where they can undergo numerous physic-chemical processes (e.g., sorption, degradation) and freely migrate. Additionally, SAAs present in the environment can be accumulated in living organisms (bioaccumulation), what can have a negative effect on biotic elements of ecosystems (e.g., toxicity, disturbance of endocrine equilibrium). They also cause increaseing solubility of organic pollutants in aqueous phase, their migration, and accumulation in different environmental compartments. Moreover, surfactants found in aerosols can affect formation and development of clouds, which is associated with cooling effect in the atmosphere and climate changes. The environmental fate of SAAs is still unknown and recognition of this problem will contribute to protection of living organisms as well as preservation of quality and balance of various ecosystems. This work contains basic information about surfactants and overview of pollution of different ecosystems caused by them (their classification and properties, areas of use, their presence, and behavior in the environment).

10.
Sci Total Environ ; 476-477: 477-84, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24496021

RESUMO

Risk assessment of industrial areas heavily polluted due to anthropogenic actions is of increasing concern worldwide. So is the case of Polish Silesia region where mostly heavy industry like smelters, mining, chemical industries as well as heat and electricity production facilities are being located. Such situation raises numerous questions about environmental state of local water bodies with special attention paid to the Klodnica Catchment which is receiving waste waters from numerous industrial plants. The efforts have been undertaken to describe the situation (spatial and temporal distribution of pollution) in the area of interest with the help of self-organizing maps - modern non-parametric data mining method - yet still rarely applied in environmental studies where numerous input parameters have to be considered. As a result of studies clear distinction into 3 pollution groups could be obtained as well as the seasonal variation of pollution could be distinguished.


Assuntos
Monitoramento Ambiental , Rios/química , Poluentes Químicos da Água/análise , Indústria Química , Sistemas de Informação Geográfica , Mapeamento Geográfico , Metalurgia , Mineração , Centrais Elétricas , Medição de Risco , Poluição Química da Água/estatística & dados numéricos , Qualidade da Água
11.
Sensors (Basel) ; 11(9): 8910-29, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22164112

RESUMO

The Fuglebekken basin is situated in the southern part of the island of Spitsbergen (Norwegian Arctic), on the Hornsund fjord (Wedel Jarlsberg Land). Surface water was collected from 24 tributaries (B1-B24) and from the main stream water in the Fuglebekken basin (25) between 10 July 2009 and 30 July 2009. The present investigation reveals the results of the analysis of these samples for their PAH and PCB content. Twelve of 16 PAHs and seven PCBs were determined in the surface waters from 24 tributaries and the main stream. Total PAH and PCB concentrations in the surface waters ranged from 4 to 600 ng/L and from 2 to 400 ng/L respectively. The highest concentrations of an individual PCB (138-308 ng/L and 123 ng/L) were found in samples from tributaries B9 and B5. The presence in the basin (thousands of kilometres distant from industrial centres) of PAHs and PCBs is testimony to the fact that these compounds are transported over vast distances with air masses and deposited in regions devoid of any human pressure.


Assuntos
Bifenilos Policlorados/análise , Compostos Policíclicos/análise , Poluentes Químicos da Água/análise , Regiões Árticas , Noruega
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