Malondialdehyde concentrations in the intestine and gills of Vardar chub (Squalius vardarensis Karaman) as indicator of lipid peroxidation

Environmental Science and Pollution Research - A lipid peroxidation product, malondialdehyde (MDA), was studied in Vardar chub (Squalius vardarensis Karaman) as an indicator of oxidative stress,...     

A comparative chemometric study for water quality expertise of the Athenian water reservoirs

The aim of the present study is to compare the application of unsupervised and supervised pattern recognition techniques for the quality assessment and classification of the reservoirs used as the source for the domestic and industrial water supply of the city of Athens, Greece. A new optimization strategy for sampling, monitoring, and water management is proposed. During the period of October 2006 to April 2007, 89 samples were collected from the three water reservoirs (Iliki, Mornos, and Marathon), and 13 parameters (metals and metalloids) were analytically determined. Generally, all the elements were found to fluctuate at very low levels, especially for Mornos that comprises the main water reservoir of Athens. Iliki and Marathon showed relatively elevated values, compared to Mornos, but below the legislative limits. Multivariate unsupervised statistical techniques, such as factor analysis/principal components analysis, and cluster analysis and supervised ones, like discriminant analysis and classification trees, were applied to the data set, and their classification abilities were compared. All the chemometric techniques successfully revealed the critical variables and described the similarities and dissimilarities among the sampling points, emphasizing the individual characteristics in every sample and revealing the sources of elements in the region. New data from posterior samplings (November and December 2007) were used for the validation of the supervised techniques. Finally, water management strategies were proposed concerning the sampling points and representative parameters.     

Chlorinated solvents in a petrochemical wastewater treatment plant: an assessment of their removal using self-organising maps

The self-organising map approach was used to assess the efficiency of chlorinated solvent removal from petrochemical wastewater in a refinery wastewater treatment plant. Chlorinated solvents and inorganic anions (11 variables) were determined in 72 wastewater samples, collected from three different purification streams. The classification of variables identified technical solvents, brine from oil desalting and runoff sulphates as pollution sources in the refinery, affecting the quality of wastewater treatment plant influent. The classification of samples revealed the formation of five clusters: the first three clusters contained samples collected from the drainage water, process water and oiled rainwater treatment streams. The fourth cluster consisted mainly of samples collected after biological treatment, and the fifth one of samples collected after an unusual event. SOM analysis showed that the biological treatment step significantly reduced concentrations of chlorinated solvents in wastewater.     

Environmetrics to evaluate marine environment quality

The environmetric data analysis of analytical datasets from sediment and benthic organisms samples collected from different sampling sites along the coast of Black Sea near to City of Varna, Bulgaria has given some important indications about the bioindication properties of both type of samples. Various multivariate statistical methods like cluster analysis, principal components analysis, source apportioning modeling and partial least square (PLS) modeling were used in order to classify and interpret the parameters describing the chemical content of the coastal sediments (major components, heavy metals and total organic carbon) and benthic organisms (heavy metals). It has been shown that seriously polluted coastal zones are indicated in the same way by all benthic species, although some specificity could be detected for moderate polluted regions' e.g. polychaeta accumulated preferably Co, Cr, Cu, and Pb; crustacea - As, Cd, and Ni; mollusca - Zn. The identified latent factors responsible for the dataset structure are clearly indicated and apportioned with respect to their contribution to the total mass or total concentration of the species in the samples. The linear regression and PLS models indicated that a reliable forecast about the relation between naturally occurring chemical components and polluting species accumulated in the benthic organisms is possible.     

The Ratio between Chronographic and Geographic Variation in the Morphofunctional Features of Bank Vole (Clethrionomys glareolus Shreb.) in the South of Its Range

Russian Journal of Ecology - A simultaneous analysis of the chronographic variation of the mandible of bank vole (Clethrionomys glareolus Shreb.) in three longitudinally distant populations that...     

Evolutionary ecological analysis of coupled geographic variation of two sympatric rodent species in the Southern Urals

Geometric morphometrics has been used to reveal coupled geographic variation in the mandible shape in two sympatric rodent species, the pygmy wood mouse (Sylvaemus uralensis Pall.) and bank vole (Myodes glareolus Pall.), in the Southern Urals. It has been shown that syntopic samples synchronously collected from the local communities of these species usually display similar, parallel, and unidirectional morphological changes as demonstrated by comparison of species pairs from different localities. The degree of concordance in geographic variation of the species makes it possible to estimate their coevolutionary potential within local communities: the wider the range of ecological conditions under which parallel variation of sympatric species is observed, the higher is their coevolutionary potential.     

Multidimensional modeling of aerosol monitoring data

The present study deals with the application of N-way factor analysis for modeling and interpretation of a three-dimensional environmental data set acquired from monitoring of particulate matter (PM) collected at four different sampling locations in Lower Austria region (Central Europe). In the study the Tucker3 algorithm for N-way modeling was used. It was statistically validated that the Tucker3 model offered having the dimensionality [222] is appropriate for correct interpretation of the relationships between chemical parameters, sampling locations and sampling period. The Tucker3 model allowed to distinguish three major sources of pollution in the region of interest conditionally named “soil dust”, “combustion” and “street dust” latent factors as responsible for chemical profile of PM and to identify seasonal variability. Additionally, some specificity of the sampling locations was also pointed out.     

Coupled Chronographic Variation of Morphofunctional Traits in Cenopopulations of Two Sympatric Rodent Species

Russian Journal of Ecology - Methods of geometric morphometrics have been used to assess chronographic variation of morphofunctional traits in the same cenopopulations of the bank vole...     

Chernov’s compensation principle and the effect of rodent community completeness on the variability of bank vole (<Emphasis Type="Italic">Clethrionomys glareolus</Emphasis>) population in the Middle Urals

Using methods of geometric morphometrics, significant differences have been revealed in manifestations of variability and morphological disparity in allochronous samples from the population of model species, the bank vole (Clethrionomys glareolus Schreb. 1780), in the Middle Urals at different levels of rodent community (taxocene) completeness in different years. Two states of the taxocene—oligospecific (two species) and polyspecific (five species)—and the level of relative abundance of bank voles (high or low) have been taken into account. Comparative analysis of variation in the size and shape of the mandible in same-aged (late-summer) young of the year has shown that significant morphogenetic differences exist between the animals sampled from the rodent taxocene at its different states (oligospecific and polyspecific) and, to a lesser extent, at high and low levels of abundance. The level of variation and the parameter of intragroup morphological disparity (MNND) in the mandible shape reach a maximum when the community has a reduced composition and decrease to a minimum when its composition is complete (i.e., in the oligo- and polyspecific taxocene). A parallelism is observed in the manifestation of morphofunctional changes of the mandible in male and female voles under conditions when the taxocene has high abundance and oligospecific composition or low abundance but polyspecific composition. Different morphogenetic responses of the population to oligo- and polyspecific composition of the community are considered as a compensatory increase of morphological disparity in the dominant species (the bank vole) under conditions of incomplete composition of the taxocene and low population density, in accordance with Chernov’s ecological compensation principle.