Search results for "Environmental Monitoring"
showing 10 items of 609 documents
Air Quality Assessment by the Determination of Trace Elements in Lichens (Xanthoria calcicola) in an Industrial Area (Sicily, Italy)
2022
This study provides data on variation in the content of metals and metalloids measured in the lichens (Xanthoria calcicola Oxner) collected in the Syracusan petrochemical complex (Sicily, Italy) which is considered one of the largest in Europe. Concentrations of eighteen trace elements measured in the lichens that were collected from 49 different points were analyzed using an inductively coupled plasma (ICP-MS) device. The concentrations of the typical elements of industrial emissions (As, Cr, Ni, and V) highlight the environmental criticality that exists in the study area. The interpretation of the data in terms of multi-element statistical analysis (FA) and enrichment factor (EFs) proved …
Dangerous relationships : biases in freshwater bioassessment based on observed to expected ratios
2018
Copyright by the Ecological Society of America The ecological assessment of freshwaters is currently primarily based on biological communities and the reference condition approach (RCA). In the RCA, the communities in streams and lakes disturbed by humans are compared with communities in reference conditions with no or minimal anthropogenic influence. The currently favored rationale is using selected community metrics for which the expected values (E) for each site are typically estimated from environmental variables using a predictive model based on the reference data. The proportional differences between the observed values (O) and E are then derived, and the decision rules for status ass…
The impact of a disused mine on uranium transport in the River Fal, South West England.
2004
Unfiltered and filtered (0.45 and 0.2 microm) water samples and sediment samples (sieved to180 microm and 180-1000 microm) were collected along an approximately 15 km transect of the River Fal, Cornwall, UK, to examine the impact of the disused South Terras uranium mine on the uranium concentrations of the river water and underlying sediments. The uranium concentration of the water samples fluctuated along the river, with the 0.45 microm filtered water showing the largest, seven-fold, difference between minimum (0.19 microg L(-1)) and maximum (1.34 microg L(-1)) concentrations. The historical uranium mine and spoil heaps were not a significant source of uranium to the river water, as water …
Sorption of uranium(VI) onto ferric oxides in sulfate-rich acid waters.
2003
The mechanisms of the uranium(VI) sorption on schwertmannite and goethite in acid sulfate-rich solutions were studied by Extended X-ray Absorption Fine Structure (EXAFS) spectroscopy. The samples were prepared under N2 atmosphere and initial uranium(VI) concentrations of 1 x 10(-5) (pH 6.5) to 5 x 10(-5) M (pH 4.2). The ionic strength was adjusted using 0.01 M Na2SO4 or 0.01 M NaClO4, respectively. The EXAFS structural parameters for uranium(VI) sorbed on goethite in sulfate-rich, acid and near-neutral solutions indicate that uranium(VI) forms an inner-sphere, mononuclear, bidentate surface complex. This complex is characterized by a uranium-ferric-iron distance of approximately 3.45 A. Ura…
Autonomous hyperspectral UAS photogrammetry for environmental monitoring applications
2014
Abstract. The unmanned airborne system (UAS) remote sensing using lightweight multi- and hyperspectral imaging sensors offer new possibilities for the environmental monitoring applications. Based on the accurate measurements of the way in which the object reflect and emit energy, wide range of affecting variables can be monitored. Condition for reliable applications is reliable and accurate input data. In many applications, installation of geometric and radiometric reference targets in the object area is challenging, for instance, in forest or water areas. On the other hand, UASs are often operated in very poor conditions, under clouds or under variable cloud cover. Our objective is to deve…
Screening of halogenated aromatic compounds in some raw material lots for an aluminium recycling plant
2004
Four samples of scrap raw materials for an aluminium recycling plant were screened for the occurrence of persistent halogenated aromatic compounds. The samples contained waste from handling of electric and electronic plastics, filter dust from electronic crusher, cyclone dust from electronic crusher and light fluff from car shredder. In our screening analyses, brominated flame retardants were observed in all samples. Polybrominated diphenyl ethers (PBDE) were identified in all samples in amounts of 245–67450 ng/g. The major PBDE congeners found were decabromo- and pentabromodiphenyl ethers. 1,1-bis(2,4,6-tribromophenoxy)ethane, hexabromobenzene, ethyl-pentabromobenzene, tetrabromobisphenol-…
Multi-elemental EDXRF mapping of polluted soil from former horticultural land.
2004
The distribution of major and trace elements was systematically investigated by use of energy dispersive X-ray fluorescence spectrometry (EDXRF) on a former horticultural soil. The purpose of the study was to combine mapping of soil element concentration levels with multivariate statistics for characterisation of soil metal pollution in relation to previous and present land use. A 1-ha study site was chosen from a former horticulture where a previous preliminary survey indicated increased concentration levels of toxic elements. The soil was sampled from the top 20 cm of the soil surface in a 10×10-m grid-like pattern covering the 1-ha study area. In addition, three soil profiles were studie…
Long-term abundance dynamics of coastal zooplankton in the Gulf of Riga
1998
The dynamics of three most abundant mesozooplankton species in the coastal zone of the Gulf of Riga — Bosmina longispina, Synchaeta baltica, Keratella quadrata — is analyzed to detect the regulating environmental factors. The only significant downward trend of species abundance was found for S. baltica in autumn. Statistically significant correlation was estimated only between the summer salinity and the abundance of B. longispina. K. quadrata though showed a negative correlation with summer salinity. The abundance of S. baltica had only nonsignificant correlations with the environmental factors. The abundance of coastal mesozooplankton species is determined by the combination of hydrologic…
Optical Methods for River Monitoring: A Simulation-Based Approach to Explore Optimal Experimental Setup for LSPIV
2021
Recent advances in image-based methods for environmental monitoring are opening new frontiers for remote streamflow measurements in natural environments. Such techniques offer numerous advantages compared to traditional approaches. Despite the wide availability of cost-effective devices and software for image processing, these techniques are still rarely systematically implemented in practical applications, probably due to the lack of consistent operational protocols for both phases of images acquisition and processing. In this work, the optimal experimental setup for LSPIV based flow velocity measurements under different conditions is explored using the software PIVlab, investigating perfo…
Hazardous air pollutants and primary liver cancer in Texas.
2016
The incidence of hepatocellular carcinoma (HCC), the most common primary liver cancer, is increasing in the US and tripled during the past two decades. The reasons for such phenomenon remain poorly understood. Texas is among continental states with the highest incidence of liver cancer with an annual increment of 5.7%. Established risk factors for HCC include Hepatitis B and C (HBV, HCV) viral infection, alcohol, tobacco and suspected risk factors include obesity and diabetes. While distribution of these risk factors in the state of Texas is similar to the national data and homogeneous, the incidence of HCC in this state is exceptionally higher than the national average and appears to be di…