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The influence of 3-methylcholanthrene to zebra mussel (Dreissena polymorpha) larvae was studied. The artificial spawning of zebra mussels was used for obtaining larvae. Two different concentrations of 3-methylcholanthrene were used. The chromosome analysis showed a significant increase in chromosome aberrations (CA) at the higher concentration of the compound. The resistance of zebra mussel larvae to the lower concentration of 3-methylcholanthrene indicated that zebra mussel larvae are probably not sensitive enough for the study of genotoxicity of the compounds from the PAH group.
Kudypy Forest District lies in the Province of Warmia and Mazury, in the vicinity of Olsztyn, the capital city of the province. The surface area of this District is almost 18 thousand ha. Kudypy Forest District belongs to the Forest Promotional Complex called the Olsztyn Forests, which covers the areas of two forest districts: Kudypy and Olsztyn. Kudypy Forest District is composed of 13 forestries and the Forest Arboretum of Warmia and Mazury, which is the main educational fascility. Arboretumis also the main attraction for visitors. Kudypy Forest District has created three educational trailsalong key features. There are also jogging and nordic-walking trails set up in Kudypy Forest District.The outdoor classrooms are situated in four forestries. The most popular type of educational activities accomplished by Kudypy Forest District in 2012–2015 were field lessons and guided trips.The engagement of Kudypy Forest District’s employees in forest education generates beneficial outcomes. The interest among children and their participation in various forms of recreationand forest education has risen over the past years in connection with increasing of the number of the Forest Distirict’s employees involved in the organization of such recreational and educational activities. The participation of adult persons has remained on a stable and relatively high level
Bream, Abramis brama (L.), eggs fertilized with genetically inactivated sperm (UV irradiation dose of 1920 J m-2) were exposed to thermal cold shock to produce meiotic gynogenotes. The shock was applied at one-minute intervals from 1 to 10 min after egg insemination. The temperature of the shock was 2.0 ± 0.1°C, and its duration was 45 min. The water temperature prior to the shock was 20.0°C. Eggs fertilized with genetically inactivated sperm (putative haploids) exhibited retarded and abnormal development. The yield of gynogenesis was relatively low, except for the group to which the shock was applied 1 min after fertilization (about 30% in comparison with the controls). Ninety fish from the control and gynogenetic groups were reared for ten months. The survival of the gynogenetic bream was twofold lower than that of the controls. The gynogenotes were highly variable in size and exhibited some morphological abnormalities. The sex ratios in the control groups were close to 1:1, whereas all the gynogenotes were female.
Angling is one of the most popular forms of recreation in Poland. The aim of the present work was an evaluation of angling potential of chosen lakes in the Olsztyńskie Lake District. Multidimensional comparative analysis was applied in this study. The study included 19 lakes. In the final assessment lakes Tejstymy, Tumiańskie and Dadaj achieved the highest potential for angling with values of synthetic measure over 0.5. The lowest values were achieved by lakes Rzeckie, Rasząg and Kraksy Małe (under 0.2). The best rated lakes were characterized by high values of synthetic measures in both studied groups of features. It was reassumed, that the lakes with low synthetic measure of the group of natural determinants were not worth to be invested. The lakes with not fully utilized natural potential and the lakes with unutilized natural potential (especially worth to beinvested) were indicated
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