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The Water Framework Directive (WFD) introduced the obligation to monitor hydromorphological elements of rivers, including hydrological regime, river continuity, and riverbed morphology. It is estimated that by the year 2015 all uniform water bodies in the EU will be ensured at least very good (class I) or good (class II) ecological status plus good ecological potential. European standards define requirements concerning slightly different quality indices as well as methods of their assessment in such studies. In Poland, hydrological valuation has been realized since the early 1990s using different research methods. Within the framework of appraisals applied at that time, the requirements of the WFD, adopted later, were not always considered. This paper presents results of an analysis conducted on the basis of the findings of all studies of the hydromorphological status of Polish rivers conducted and published in 1995-2008. From 2,202 km of watercourses, in which scoring was applied for selected quality elements, a total of 1,588 km, uniform in terms of methodology, were selected from 35 rivers. Statistical analysis determined the distribution of results for analyzed quality elements, constituting the foundation for a new method of hydromorphological monitoring of rivers, adapted to the requirements of the WFD. Moreover, our paper also presents a review of developed research methods for the hydrological valuation of watercourses, applied in Poland and Europe.
The article presents the results of the studies of lichens in streams and spring areas of the escarpment zone of Wzniesienia Łódzkie Heights in Central Poland. The boulders, stones and roots of Alnus glutinosa, situated in 3 inundated zones in the streams: submerged zone, fluvial mesic zone and fluvial xeric zone, were examined in the streams. The studies have shown 23 species connected with these streams. Six species of freshwater lichens: Verrucaria aquatilis, V. hydrela, Hydropunctaria rheitrophila, V. margacea, V. praetermissa and V. madida, occupied stones in 3 different zones. Verrucaria aquatilis and Hydropunctaria rheitrophila colonized also secondary substrates – the bark of alder roots incrusted with sand grains and silt.
In the result of geomechanical transformations associated with the activity of open cast brown coal mining, some changes in air-water relations may occur on arable land adjacent to these regions usually referred to as hvdrological alterations. However, they do not always need to result in soil degradation, i.e. in the deterioration of their production potentials. This will often depend on the distance of fields from the workings, value of the arable land (soil quality class), type of water management, etc. On the basis of long-term studies carried out in the area of operation of two brown coal mines - KWB "Konin" and "Adamów" - on arable land and grasslands of over 60 villages on the total area of 30 thousand hectares it was possible to develop evaluation criteria for the extent of soil degradation and work out principles for compensation payments for farmers. Three zones and appropriate sub-zones of soil susceptibility to drainage were determined and clear and simple criteria for the estimation of the extent of arable land and grassland degradation were worked out. Furthermore, the authors proposed simple and readable systems to calculate compensatory payments to be paid to farmers taking into account the state of soil degradation, value of agricultural land (price of 1 ha of land of appropriate class) and the area of damaged land. The degree of soil degradation, both of arable land and grasslands, ranged from 10 to 30%. In the case of grasslands, additionally, an appropriate sum of money was allocated to compensate for sward recultivation.
The aggregations of V. viviparus were observed in the littoral of Zegrzyński Reservoir (Central Poland), and in the outfalls of its tributaries. They were present over five years of studies (1990-1994), at the same sites. The densities of snails in the aggregations differed among the sites (from over 800 to 500 ind. m⁻² in the reservoir itself), and showed seasonal changes with maximum in summer, and minimum in spring and fall. Swarming of the snails was related to the environmental changes and biology of this species. Tendency to form bigger snail conglomerations in the mouth sections of the rivers results from continuous inflow of organic matter being food supply for these organisms.
Pulsatilla vernalis is a rare species in the Polish lowlands, strongly threatened by anthropogenic disturbance of its habitats. A grave decrease in its populations has been observed during the past 60-80 years (analogous populations in Eastern Austria and the Czech Republic are almost or completely extinct). An analysis of the genetic diversity of populations in the Polish lowlands was performed to estimate its level and distribution. The AFLP method was used for the study of seven populations. An analysis using five pairs of selective primers revealed 446 scorable fragments; 62.1% of them were polymorphic. The average gene diversity indices was 0.17 (the mean value for all the populations), ranging from 0.139 to 0.204. A weak relationship between diversity and population size was revealed. Most of the genetic diversity was contributed to by the within-population level (AMOVA) and only a weak geographical structure was shown by UPGMA clustering. Four populations formed population-specific clusters while three others (from one region) were intermixed. These preliminary results show a moderate genetic diversity of the studied populations, which was still rather high when compared with their size. This result, together with the low between-population differentiation in the region, suggests that these populations are the remnants of larger populations that, only a few decades ago, were much less isolated.
The actinomycetes in water samples and bottom sediments of lowland, eutrophic lake as well as in soil (farmland, sandy) of the lake basin were studied. Chitin-degrading actinomycetes were isolated (with a plate technique) from each habitat; subsequently, their chitinolytic activity (with the fluorometric method) was determined in relation to temperature (10–50°C) and the physical type of chitinous substance (colloidal chitin, chitin powder, and shrimp shells). This study demonstrated that actinomycetes were the most abundant in soil samples (average of 18 × 10³ CFU g⁻¹ in farmland soil, 9 × 10³ CFU g⁻¹ in sandy soil), and the least abundant in water samples (average of 2.7 × 10¹ CFU mL⁻¹ in lake water at neutral pH, 0.6 × 10¹ CFU mL⁻¹ in lake water with alkaline pH). The highest percentage of chitinolytic actinomycetes was observed in soil (average of 80% in sandy soil and 85% in farmland soil). Chitinolytic actinomycetes also made up a large fraction of total actinomycetes in water samples (average of 73%). In silt and sandy sediments, percentages of chitinolytic actinomycetes equaled 23 and 15%, respectively. Actinomycetes collected in soil were characterized by the highest activity (average of 14 nmol MUF mg⁻¹ of protein h⁻¹ in farmland soil, 8.5 nmol MUF mg⁻¹ protein h⁻¹ in sandy soil). The lowest activity was observed among benthic actinomycetes (average of 5.4 nmol MUF mg⁻¹ of protein h⁻¹ in silt, 0.65 nmol MUF mg⁻¹ protein h⁻¹ in sandy sediments). The impact of temperature and the type of chitinous substrate on the activity of chitinases produced by actinomycetes demonstrated that their activity peaked at 40°C and in the presence of colloidal chitin. Observed differences in actinomycetales number and activity in the lake and the soil may be explained by higher accumulation of chitin substances in the soil. This polymer allows microorganisms to continually synthesize chitinolytic enzymes and take active part in that compound decomposition.
The paper presents soil conditions of Pulsatilla vernalis in the Polish lowland. There were determined species preferences in relation to physical and chemical properties, grain size composition and the type of soil. It has been found that P. vernalis prefers very poor sandy, acid, dry and permeable soils, with small water capacity. The range of habitat parameters at the lowland sites differs, however, from the conditions at the mountain sites. Due to specific habitats of the species, new ecological indicator values were proposed for the lowland sites of P. vernalis. The results of soil analysis presented in this paper, as well as other data related to biology of the species, should be accounted for in the active protection plan, including the processes of reintroduction and introduction of the species.
Data on seasonal dynamics of bat activity in central Europe are scarce, mostly restricted to either summer period or autumn swarming. Few studies provide extensive interspecific comparisons of temporal activity patterns. Through broadband ultrasound detection, temporal variation of flight activity was studied in seven insectivorous bat species in N Poland for the first time. Seasonal activity pattern ofMyotis daubentonii (Kuhl, 1817) was clearly bimodal with the higher peak of activity in April and the second, smaller peak in August–September. The first peak is possibly associated with post-hibernal restoration of fat reserves, while the second one might result either from pre-hibernal fat accumulation, increase in energy demands of males during spermatogenesis or from dispersal of newly weaned juveniles. The highest flight activity ofNyctalus, Eptesicus andPipistrellus bats was noted in summer months, reflecting mainly an increase in energy demands between pregnancy and lactation. However, a distinct, second peak in activity ofN. noctula appeared at the end of September, probably matching the late migration wave of individuals from E Europe. The cluster analysis of species’ activity patterns reflected division on different hunting tactics, but not migratory behaviour.
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