- Dettagli della rivista
- Pubblicato per la prima volta
- 17 Mar 2011
- Periodo di pubblicazione
- 4 volte all'anno
- Accesso libero
Assessment of DDT, HCH and PCB pollution of lake sediments in Poland
Pagine: 63 - 74
In the years 2010-2013, 528 samples of surface sediments were collected from lake depths in the area of Poland. The content of 7 PCB congeners, HCH isomers and p,p’-DDT, p,p’-DDE and p,p’-DDD was determined using the GC-ECD method. The studies showed the common occurrence of organochlorine compounds in lake sediments in Poland. The presence of HCHs, at a concentration above the determination limit, was detected in 83.71% of samples, that of DDTs in 98.86% of samples, and of PCBs in 98.86% of samples. The maximum HCH concentration was 60.7 ng g-1, that of DDTs 602.9 ng g-1, and of PCBs 50.7 ng g-1, while the averages were 6.3 ng g-1, 19.2 ng g-1 and 2.8 ng g-1, respectively. High levels of DDTs are found in sediments of those lakes upon which major towns are located, whereas the highest HCH concentrations are observed in sediments of the lakes upon which holiday centres and agrotourism facilities have developed. The ratio of concentrations of total DDT metabolites to p,p’-DDT was above 2 in almost all samples, and the value was most frequently from several to tens (average 28.3). Sediments of some lakes contain higher concentrations of γ-HCH and DDT metabolites than their PEC values, the content of γ-HCH was higher in 1.89% of the analysed samples, the content of p,p’-DDE in 3.78% of the samples, and the content of p,p’-DDD in 7.38% of the samples. Concentrations of p,p’-DDT and PCB in excess of the PEC value were not found in any of the samples tested.
- lake sediments
- Accesso libero
Factors affecting the distribution patterns of aquatic macrophytes
Pagine: 75 - 81
Aquatic macrophytes constitute important components of many freshwater ecosystems. The manifold role of aquatic macrophytes in freshwater habitats is closely linked to their distribution, which in turn depends on a myriad of factors. Foremost, among these are light, water temperature, water quality changes and nutrient enrichment, sediment composition and fluctuations in water levels. Light and temperature are of paramount importance in determining the distribution (with depth, season and latitude), thereby influencing productivity and species composition as well. Sediment compositions markedly affect the growth rates of macrophytes which in turn have a profound influence on the distribution of aquatic macrophytes. Water quality changes and nutrient enrichment can cause considerable variations in the species richness, composition, and density of aquatic vegetation. The reduction in water levels could bring drastic changes in the species composition and distribution of macrophytes. Factors associated with competition, herbivory, land use and land cover changes etc. also play an important role in shaping macrophyte distribution and community structure. In this review we examine both biotic and abiotic factors that influence the structural attributes like species composition, distribution, abundance and diversity of aquatic macrophytes.
- Abiotic and biotic factors
- aquatic macrophytes
- freshwater ecosystems
- species composition
- Accesso libero
Taxonomic features of fruits and seeds of Nymphaea and Nuphar taxa of the Southern Baltic region
Pagine: 83 - 91
Research was carried out on fruits and seeds of Nymphaea and Nuphar taxa collected from Poland, Latvia and Estonia. The aim of the research was to establish diagnostic features which could enable identification of the examined taxa on the basis of the fruit and seed structure and creating a key to identify them. The examined organs were observed through an optic microscope and scanning electron microscope (SEM). New diagnostic features were discovered: spotting of fresh pericarp, the range of the fruit shape coefficient, the colour of the rays in the fruit stigma disc, the thickness of the seed testa, ribs in the seeds, and occurrence of the “puzzle shaped” cells on the surface of the testa. The discovered features were used in the taxonomic characteristics.
- Accesso libero
Anthropogenic change in water bodies in the southern part of the Silesian Upland
Pagine: 93 - 100
The paper analyses the anthropogenic change in water bodies in the southern part of the Silesian Upland as exemplified by the town of Knurów. The assessment was based on topographic maps from the years 1827-1828, 1928-1936, 1960 and 1993, and on a 2011 orthophotomap. The cartographic materials used were processed as required for analysis purposes. Maps were calibrated in the Quantum GIS program on the basis of map corner coordinates and using the common points method. In Knurów, four main types of water bodies were distinguished with respect to their origins: reservoirs impounded by dams, flooded mineral workings, industrial water bodies and water bodies in subsidence basins and hollows. Historically, the first water bodies to appear were reservoirs impounded by dams, which dominated until the 1930s. They later fell into disuse and were completely dismantled. Water bodies in mineral workings formed in the early 20th century and were associated with the excavation of raw materials for producing bricks. The period of their greatest significance were the 1960s, when they constituted slightly more than 46% of water bodies in total and accounted for nearly 40% of overall surface area. At the end of the 19th and at the beginning of the 20th century, industrial reservoirs began to appear. Within the town of Knurów, those were sedimentation tanks that held mine water, washery effluent, backfill and cooling water, fire-fighting water pools and tanks, tanks at sewage treatment plants, industrial water tanks and others. Presently, these account for 41.4% (29) of the total number of water bodies and have a total surface area of 32.0 ha (25,2%). Within the study area, water bodies in subsidence basins and hollows only began to form in the second half of the 20th century. In 2011, such water bodies numbered 38 (54.3%) and occupied an area of 90.4 ha (71.2%).
- Silesian Upland
- water reservoirs
- Accesso libero
Oxidative response of wetland macrophytes in response to contaminants of abiotic components of East Kolkata wetland ecosystem
Pagine: 101 - 108
The tannery effluent and composite municipal sewage water drained to the East Kolkata wetland (EKW), a Ramsar Site (1208), is used for agriculture and pisciculture after natural stabilization. Such composite wastewater is characterized by exceedingly high total dissolved solids, total hardness, chloride and heavy metals concentrations. These water born pollutants generate reactive oxygen species which are potentially toxic to the biological system. These reactive oxygen species are normally detoxified by some enzymes, such as superoxide dismutase (SOD) and catalase (CAT). The present study was commenced to find out the SOD and CAT activities against the oxidative stress, if any, in four macrophytes namely, Eichhornia crassipes, Pistia stratiotes, Alternanthera sessilis and Sagittarria montevidensis of contaminated ponds (Site 1 and Site 2) of EKW and an uncontaminated site (Control site). During the course of sampling the physico-chemical factors were found significantly higher in the EKW ponds compared to the control site. In the EKW sites, higher rate of evaporation during summer months caused higher elemental concentration in the premonsoon than in other seasons. This led to high activity of both SOD and CAT enzymes. In contrast, heavy rain fall in monsoon lowers the elemental concentration - mainly due to dilution effect. Present experiment indicated that in a stressed ecosystem like EKW, the wetland plants overcome the stress by altering their stress enzyme activities, hence suggesting an evidence of adaptive mechanism to thrive in a stressful environment.
- East Kolkata Wetland Ecosystem
- tannery effluent
- oxidative stress
- superoxide dismutase