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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.
Extensive disintegration of spruce forests in the Beskidy Mts. in South Poland generates a need to regenerate sizeable areas as well as to rebuild forest stands which have defended themselves against breakdown. In practice, the magnitude of relevant management tasks does not allow for keeping up with the progressive destruction of forest, especially at higher altitudes, where natural regeneration does not occur as much as necessary. In addition, the species composition is limited to spruce, sometimes accompanied by beech and fir, whereas other species have a negligible share. What may be helpful in solving this problem is the method of regeneration of such areas and of establishment of under-canopy cultures, consisting of patchwork, multi-stage regeneration task performance, starting from the areas with the best chance of reforestation success and using the existing self-sown trees. Such areas undoubtedly include habitats with better water balance, i.e. humid habitats (in the case of larger areas, distinguished in the forest management plan as humid forest site types). The aim of the present study was to propose management of watercourses and headwater areas in the region of the Skrzyczne massif where the selected catchments are situated on the southern (the Malinowski Stream) and the northern (the Roztoka Czyrna stream) slopes of this massif. The research was carried out in August 2012 and included juxtaposition of available hydrological maps with actual field conditions along with identification of springs and streams and the course of their beds in order to update the existing data. The updating of the forest numerical maps in the existing databases of the State Forests IT System (SILP) included verification of the course of streams and determination of their nature (penament or periodic) with a division into the existing ones and the added ones. The data was recorded against the background of the division of the forest surface, contour lines, major roads, climate and plant floors and forest habitat types. The total length of streams was ascertained. The catchment areas and areas along their beds were determined by adopting variable distances from the beds, depending on climate and plant zones and the slope gradient. The adopted distances were: 5 m in the upper forest zone, 10 m in the middle forest zone, 20 m in the lower forest zone on both sides of the bed and in the headwater area within the radius of 10 m from a source. Specific sylvicultural procedures in headwater areas and in the neighbourhood of watercourses were described in each climatic and vegetation zones.
The knowledge of the genetic variability and structure of Salmo trutta population is needed for effective protection of the species and rational management of the resources. A number of marker systems have been introduced to evaluate the genetic variability of trout populations. Among them, the most often used are the RAPD and SSR markers. Both marker systems are classified as type II markers (O’BRIEN 1991, LERCETEAU-KÖHLER and WEISS 2006). In this study, the genetic variability of the Salmo trutta m. fario and Salmo trutta m. trutta populations from the Rega river, and the three watercourses Sitna, Słopica and Bagnica of the Drawa river catchment area, were analysed. One stream, the Chojnówka (located outside the catchments of the above streams), was used as an extra study area. Based on two marker systems, different results were obtained. In the case of RAPD analysis, all loci were polymorphic in all populations. The use of these marker systems permitted the construction of UPGMA similarity trees. The trees revealed a division of the analysed populations into two groups: one group from the Słopica river and the other group from the remaining watercourses. In the second similarity group, two subgroups can be distinguished: one comprising the population of the sea trout from the Rega river and that of the brown trout from the Sitna river (60.7%), and the other consisting of the parr trout populations from the Chojnówka, Bagnica and Sitna (50.3–79.4%). Between the analysed populations, 100% polymorphism was found. The results indicate a high genetic variability of the studied populations. In the case of SSR analysis, 9 microsatellite loci isolated from five trout populations were described. The number of alleles at these loci ranged from 1 to 5 with an average of 2.8 alleles per locus. The expected heterozygosity ranged from 0.07 to 0.66, with an average of 0.35. The results indicate high genetic variation of the populations studied.
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