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The publication deals with changes in major physical and chemical parameters of water in the Slup dam reservoir, that took place within 1984 - 2000/2001. The reservoir is situated on River Nysa Szalona. Water of the Nysa Szalona, its tributaries, and the Slup were examined at monthly intervals within February 2000 - August 2001. The Nysa Szalona water supplied to the Słup was found to be twice as nutrient-rich at present as it was in the 1980s. The reservoir water contains higher ammonium concentrations. Mean values of trophic state indices in 2000/2001 were lower than those recorded in 1984/1985.
W 2011 roku przeprowadzono badania zawartości metali ciężkich oraz związków biogennych w wybranych siedliskach płazów w Ostrowie Wielkopolskim. Wartości kadmu i ołowiu we wszystkich badanych zbiornikach przekroczyły maksymalne dopuszczalne stężenie dla substancji priorytetowych z grupy wskaźników charakteryzujących występowanie substancji szczególnie szkodliwych dla środowiska wodnego określonych w Rozporządzeniu Ministra Środowiska z dnia 9 listopada 2011 roku. Stężenia związków biogennych nie przekroczyły wartości letalnych dla płazów. Badane siedliska wymagają natychmiastowych zabiegów ochronnych, gdyż występujące zagrożenia mogą doprowadzić do wyginięcia lokalnych populacji płazów
The study covered the aquatic environment of two small rivers in Western Pomerania, Poland, such as the Czerwona and the Grabowa. Its purpose was to determine aluminium bioaccumulation in the aquatic environment by testing water, bottom sediments and aquatic plants. Samples were taken in the summers of 2008-2011. pH, electrolytic conductivity and aluminium concentration were determined in water samples, while the sediment and plant samples were submitted to analyses of the aluminium content. The water pH oscillated between 6.04 and 8.95, while the electrolytic conductivity ranged from 440 to 1598 μS cm-1. The aluminium concentration in the river water was up to 0.138 mg Al dm-3 in the Czerwona and up to 0.425 mg Al dm-3 in the Grabowa. The maximum aluminium content in the bottom sediments was 47.01 mg Al kg-1 in the Czerwona River and 26.15 mg Al kg-1 in the Grabowa River. The maximum aluminium content in the aquatic plants sampled from the Czerwona was 91.63 mg Al kg-1, and from the Grabowa – 1,077 mg Al kg-1. The bioconcentration factor (BCF) of aluminium for the Czerwona River ranged from 5.06 to 24,052, and for the Grabowa River – from 1.10 to 70,132. The concentration factor (CF) of aluminium in the bottom sediments oscillated between 66.72 and 23,492 in the Czerwona River and between 14.81 and 2,763 in the Grabowa. The aluminium content in the two rivers was relatively low in the water, sediments and aquatic plants, which is typical of environments without strong anthropopressure. The values fell within the limits set by environmental water quality standards. The low aluminium accumulation degrees in the biotic and abiotic components indicate that the environments of the two rivers have a low load of aluminium compounds.
Extrauterine pregnancy has been diagnosed in many species to date, but nevertheless it is a rare disorder. This disorder can occur as a tubal pregnancy or an abdominal pregnancy and can also develop as a primary or secondary form. In contrast to women, where the localization of an extrauterine pregnancy in the oviduct is most frequent, in farm animals the secondary, abdominal form, is predominant. This paper describes the relations between the types of ectopic pregnancy and species, propitious factors, consequences for females and for the embryo or fetuses developing out of the uterus.
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The research involved Słup Dam Reservoir, which is used as a source of drinking water and for flood prevention. The research material was made up of aquatic plants and water collected in the littoral zone of the reservoir, in which copper, nickel, cadmium, lead and zinc contents were determined. Ceratophyllum demersum L. turned out to be the best accumulator of nickel, cadmium and zinc, Potamogeton crispus L. – copper, and Phragmites communis Trin – zinc. The presence of plants in the backwater area of the dam reservoir definitely improves water quality, not only thanks to their metal accumulation properties but because of their ability to act as a filter of substances carried in the water.
Our study was conducted in the area of the Parseta and Radew rivers in 2012 and 2013. Samples were taken of water and bottom sediments. In terms of their physico-chemical composition, the tested waters can be characterized as slightly polluted. In terms of zinc and copper concentrations, the waters belong to purity class I, but the contents of cadmium, lead, and nickel exceed the Proposed Environmental Quality Standards for Priority Substances. As far as copper, nickel, zinc, and cadmium are concerned, the studied sediments were not polluted, and the geo-chemical index values were within class I. The relevant accumulation rates for metals in sediments can be ordered as follows: Cd
We used brown bullheads (Ictalurus nebulosus) from Milicz Ponds in our study. The authors examined the impacts of age, body length, body weight, and the condition of the fish on concentrations of metals (Cd, Pb, Ni, Cu, and Zn) in their muscle tissue (n=62). The metal contents in muscle tissue increased in the order from Cd < Ni < Pb < Cu < Zn and amounted to 0.0177, 0.0754, 0.1121, 0.1979, 4.7358 mg/kg of wet weight respectively. Also, the bioconcentration factors (BCF) were calculated based on the metal contents in muscle tissue, water and bottom sediment. The obtained results allow us to conclude that the metal concentrations in muscle tissue decrease with age (for Pb and Zn, the correlation is highly statistically significant, with the p value ≤0.01). A relationship between body length and weight and Zn content (p≤0.01) was confirmed, as well as between the condition of the fish (expressed by Fulton’s condition factor) and Cd and Cu concentrations (p≤0.05).
Nanotechnology offers manufacturing and use of structures in which at least one dimension is expressed in nanometers. An increasing number of everyday products contain some ingredients in molecules size. One of them – Ag-nanoparticles (nanosilver) – is commonly used due to its biocidal properties. There is a serious risk of nanoparticles being released into the environment, especially to the soil or surface water. Because of low selectivity of silver-nanoparticles in water it is not an environmentally-friendly product (destroying aquatic microflora and fauna). The aim of this study was to determine the effect of Ag-nanoparticles on the growth and survivability of three water plants: Oedogonium sp., Versicularia dubyana, and Lagarosyphon madagascariensis. Plants were treated with silver nanoparticle solutions of concentrations ranging from 0.0 to 10.0 mg·dm⁻³ Ag (NANO SILVER product by NANOCO Corp.). Light conditions were controlled through 16-hour light cycle using a 15W Tungsram lamp. The whole experiment was carried out over 10 days. Changes in plant morphology and growth in various Ag-nanoparticle concentrations were observed. Ag-nanoparticles showed biocidal activity for Oedogonium sp. after 24 hours of incubation in solutions with a concentration of 1.0-10.0 mg·dm⁻³ Ag. Plants were dark, destroyed, and sank to the bottom. In samples with higher plants, nano silver caused blackening and some plant deaths at concentrations of 5.0 and 10.0 mg·dm⁻³ Ag, or inhibited their growth in lower concentrations. Selective activity of nano silver may be useful for eliminating unwanted plants. However, its uncontrolled release into the environment may be harmful to aquatic organisms and devastating for entire ecosystems.
Tests performed in 2013 and 2014 revealed the occurrence of three tick species parasitizing pet cats and dogs in the Wrocław Agglomeration. In total, 1,455 tick specimens were removed from 931 hosts (760 dogs and 171 cats) in 18 veterinary clinics. The dominant tick species was Ixodes ricinus (n=1272; 87.4%), followed by I. hexagonus (n=137; 9.4%) and Dermacentor reticulatus (n=46; 3.2%). Females were the most often collected development stage among I. ricinus and D. reticulatus, and nymphs among I. hexagonus. Additionally, D. reticulatus ticks (n=337) were then collected from vegetation in the Wrocław area to detect Babesia canis; however, none was found positive. Only 9.0% of dog blood samples sent to VETLAB were positive for Babesia spp. Negative results for B. canis from ticks may result from the short period of the occurrence of D. reticulatus in the Wrocław area and therefore the vectorpathogen cycle may not have been fully established at the time of the study. Nevertheless, D. reticulatus is expanding its range, and the size of its population in the Wrocław Agglomeration is increasing. The presence of the pathogenic Babesia spp. combined with the occurrence of its main vector¸ D. reticulatus, suggests that the epizootiological situation in the area can change and may pose a new veterinary problem in the future.
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