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Abstract

This work brings an evaluation of the quality of littoral zone of Algerian in two neighbouring port coasts, namely, Honaine and Beni Saf, chosen as significant discharge sites. This was followed by a comparison of the state of these coasts with those of the Mediterranean coastal areas. The study was conducted in all seasons in the year 2011−2012 by measuring the hydrological physicochemical parameters (pH, temperature, turbidity and salinity) and using sea lettuce Ulva lactuca as significant ‘biomarker of the quantity of metal contaminants (Cd, Pb, Cu and Zn)’. Harvesting of Ulva and the seawater samples were performed in each season in three stations, characterised by discharges of waste and industrial water and saline discharges from the recent installation of desalination in Honaine. The metal concentrations in seawater showed significant variations between stations and the harvest season, resulting in the appearance of pollution of Cd, Pb, Cu and Zn. Also this result was manifested in Ulva in the station S1 (Beni Saf) and S2 (Honaine-beach) with the exception of copper. These results have exceeded tolerable international standards.

Abstract

The toxicological study conducted revealed high concentrations of hydrocarbons and highly toxic heavy metals in the liver and subcutaneous fat of the Caspian seal. The increased toxicant level in the fat, as compared to the liver, pointed to the disorder of organism purification processes, leading to chronic polytoxicosis and disorders of the histological structure of the internals. The studies of the morphofunctional state of the stomach of the Caspian pinnipeds revealed the following disorders: hemorrhages, edemata and necrosis of the mucous membrane, and replacement of glandular tissue with the connective tissue. The study of the small intestine of the seals identified the symptoms of catarrhal desquamatory enteritis. Epithelium dystrophy and desquamation were noted, in particular at the tops of the villi. Different types of colitis (acute, ulcerative, chronic) were found in the large intestine of the seals. Dystrophic and necrotic changes of hepatocytes were identified in the liver tissue, which pointed to the liver cell failure. The nature and extent of pathological changes in the internals and tissues of the studied animals point to the functional depression of the digestive system.

Abstract

This paper concentrates information on the flash flood produced during 02-04.06.2016 in the Trotuş River basin. Maximum flows have been analyzed by reference to the thresholds corresponding to the Defense Levels. In order to show in a suggestive way the amplitude of the event, the characteristics of the flood were highlighted as well as a series of morphometric and hydrological data on the maximum flow of the Trotuș River. The hydrometric stations in the basin area, to which reference was made, were: Lunca de Sus, Goioasa, Tg. Ocna, Onești and Vrânceni. The flow series were represented graphically to be able to easily observe the evolution of the flood over time. The analysis showed that the flood produced on the Trotuș River had a great magnitude causing significant damages.

Abstract

The paper analyzed the annual number of days with precipitation from 4 weather stations located in Maramureş County, during 1961-2016. The frequency of these days, their spatial and temporal variability, the decennial distribution of the number of days with precipitation, the trend and the assurance degree of the annual number of days with precipitation were also studied. The result was that in Maramureș County, between 157 and 194 days with precipitation occur on average per year. The mean annual number of days with precipitation increases from west to east, as the altitude of landforms increases, but also from south to north, as latitude increases. The analysis of the rainy and dry yearly intervals reveals the appearance of several extreme years towards the end of the analyzed period, in the last decade and a half (2000-2016). The linear trend of the annual number of days with precipitation is slightly increasing at the lowest station Baia Mare and decreasing at the other stations. The wettest decades were the 5th (2001-2010) and the 1st (1961-1970), and the driest decades were the 6th (2011-2016) and the 3rd (1981-1990). On the territory of Maramureş County, the values corresponding to the characteristic assurances (1, 2, 5, 10, 20, 25, 50, 80 and 100%) of the annual number of days with precipitation increase from west to east and from south to north. Once every 100 years, between 225 and 273 days with precipitation can occur in Maramureș.

Abstract

The identification of areas with flood potential risk is important concerning the rational management of emergencies in case of floods. The most significant floods in the history of Romania occurred in the catchment basin of Siret (Uz River being an indirect tributary) and Prut. The analysis focused on the identification of flood potential risk index. The study involves the analysis of natural and anthropogenic physical and geographic factors: lithology, land declivity, soil texture, profile curvature and land use. The weighting of each analyzed factor for the contribution to floods was obtained using the AHP extension of the ArcGIS software. This methodology was applied for the lower Uz river basin, situated downstream from Lake Poiana Uzului. The catchment basin of Uz was affected by major floods in the summer of 2005, while the Uz River recorded a maximum historic discharge of 132 m3/s, at the precipitation station of Darmanesti, situated upstream from the Poiana Uzului reservoir. The consequences of the historic high water were serious. Extended surfaces within the major riverbed were flooded, numerous houses were partially damaged and some destroyed. The study highlights that the highest values of flooding index range between 3.96 and 4.71 and that they affect 14% of the entire surface of the studied area.

Abstract

Present study is dedicated to assessment and analysis of flood runoff and its spatial distribution in the limits of the Republic of Moldova. SCS-CN model and GIS were used as main methods and techniques for runoff assessment. Main components which were considered for flood runoff estimation are soils (soil texture and moisture condition), land cover and rainfall (for 1% probability). The results showed the region that is the most affected by flood runoff is northern part of the republic with flood runoff >100 mm, the lowest flood runoff values being estimated for the southern part of the country with <50 mm. Soil moisture conditions have a important impact on flood runoff amount, increasing its averages with 30 to 60% in case of wet condition and decreasing it with 35-65% in case of dry soil. It was also observed that flood runoff distribution is highly influenced by land cover, the average values being twice as high in urban area than under natural vegetation.

Abstract

As the production of single use plastic packaging materials is increasing rapidly, the resultant generation of waste material is quickly becoming one of the world’s major environmental issues. These plastic materials are highly stable, with excellent material properties which can allow them to be used beyond their intended single use. To effectively utilize these recovered plastic materials, an understanding of their mechanical properties is required. The aim of this study was to assess the mechanical properties of recovered plastic bottles to prove the feasibility of utilisation for additional uses in non-shredding based recycling systems with lower energy requirements. This system would conserve the physical integrity of the bottles, using them as a raw material for new direct reuse and repurposing applications. Tensile tests were conducted on samples cut from polyethylene terephthalate (PET) bottles considering different sets of variables: cutting method, orientation of the samples and degradation method. The results clearly demonstrate the superior strength characteristics, and minimal effect of degradation, showing the potential for a whole new field of applications where these recovered materials could be used. However, successful adoption of this new concept relies on structural changes to the operations of recycling and manufacturing companies as well as legislators, regulators and the general public.

Abstract

This paper examines changes in alpine vegetation over 50 years in the Western Tatras part of the Western Carpathians Mountains in Slovakia. We focus on the following most widespread vegetation types: subalpine to subnival grasslands (alliance Juncion trifidi Krajina 1933), snowbed vegetation (alliance Festucion picturatae Krajina 1933) and dwarf-shrub vegetation (alliances Loiseleurio-Vaccinion Br.-Bl. in Br.-Bl. et Jenny 1926 and Vaccinion myrtilli Krajina 1933). The historical 1971–1977 sampling dataset was re-sampled in 2016–2017 and our research is based on a comparison of 40 pairs of these relevés. Herein, we studied (i) changes in species frequencies; (ii) changes in phytodiversity and site conditions using estimates of Ellenberg’s eco-indices and (iii) comparison of historical and current relevés over time using the nonmetric multidimensional scaling gradient analysis (NMDS) ordination method. The frequency curves reveal differences; especially in the most frequent species at 37.5−80%, which reach higher values in the current data. The higher 7.5−25% value of medium-frequent species in the historical relevés indicates progressive homogenisation of the examined vegetation. In addition, the Shannon-Wiener index of individual vegetation types revealed no significant differences in diversity or average number of species. The historical relevés included 75 species while 74 were confirmed in the current data. Statistically significant differences were determined in light factor for all three vegetation groups. This was due to the retreat of some light-demanding species. While NMDS indicated changes in Festucion and Vaccinion relevés over time, the Juncion group relevés did not follow this trend, thus confirming their high stability. The observed changes between current and historical data are attributed to changes in climate and altered land use with the cessation of grazing.

Abstract

This study analyses the changes in woodland cover from the mid-18th century to the turn of the 21st century in a distinctive region of the Czech Republic – the Karviná district. This region has been substantially affected by the process of industrialisation during the 19th and 20th centuries, which transformed a formerly agricultural landscape into a landscape heavily impacted by underground coal mining and related landscape processes. The occurrence of woodland cover in the Karviná district was determined from historical military maps (second half of the 18th century, first half of the 19th century, second half of the 19th century, first half of the 20th century) and from a colour orthophoto (2017) verified with reference to a contemporary map. The article interprets the occurrence of woodland cover depicted in the abovementioned sources and presents an interpretative key. The vectorisation of the woodland cover and the analysis of temporal–spatial changes in woodland cover were conducted using ArcGIS 10 software.

Abstract

The work shows historical pollution aspects of the soil on a range of approximately 2000 m2 located in the east of Botosani city at the loading platform/discharge heavy fuel oil in the enclosure thermal power company S.C. Modern Calor found S.A. This study was based on a series of works based on projects of soil and groundwater investigation in the area of the heating company S.C. Modern Audit Office found S.A. Soil contamination is the result of pollution over time, which is due primarily to faulty-urilor occurring during operation of the pipes or the sewage system in the territory of society of heating, to the lines of transport heavy fuel oil.At present, industrial pollution control, requirements imposed by Community acquis on environment, shall be carried out on the basis of directive (IPPC Directive, Directive LCP) and other techniques of the medium (BAT-s corresponding BREF, in the industrial sector). By these tools are prevents and controls in full pollution, thereby reducing industrial pollution.