Biological indices applied to benthic macroinvertebrates at reference conditions of mountain streams in two ecoregions (Poland, the Slovak Republic)

The study was carried out from 2007 to 2010 in two ecoregions: the Carpathians and the Central Highlands. The objectives of our survey were to test the existing biological index metric based on benthic macroinvertebrates at reference conditions in the high- and mid-altitude mountain streams of two ecoregions according to the requirements of the EU WFD and to determine which environmental factors influence the distribution of benthic macroinvertebrates. Our results revealed statistically significant differences in the values of the physical and chemical parameters of water as well as the mean values of metrics between the types of streams at the sampling sites. RDA analysis showed that the temperature of the water, pH, conductivity, the stream gradient, values of the HQA index, and altitude were the parameters most associated with the distribution of benthic macroinvertebrate taxa and the values of the metrics. The values of biological indices should be considered according to the stream typology including altitude and geology. At the reference conditions, the suggested border values of biological indices are very harsh. The values of the biological indices of most sampling sites did not correspond to the requirements of the high status in rivers. The streams at altitudes above 1,200 m a.s.l. should be treated as another river type and new reference values should be established

Development of comprehensive river typology based on macrophytes in the mountain-lowland gradient of different Central European ecoregions

The aim of the study was to identify the vegetation pattern in the different types of watercourses basing on survey in reference conditions in a wide geographical gradient, including mountain, upland and lowland rivers. We tested relationship between composition of macrophytes to environmental variables including: altitude, slope, catchment area, geology of valley, land use, hydromorphological sfeatures, water physical and chemical measurements. Analysis based on 109 pristine river sites located throughout major types of rivers in Central Europe. Qualitative and quantitative plant surveys were carried out between 2005 and 2013. Based on TWINSPAN classification and DCA analysis, six macrophyte types were distinguished. The lowland sites were divided into the following three types: humic rivers and two types of siliceous rivers depending on the catchment area, including medium-large and small rivers. The mountain and upland rivers were divided into three geological types: siliceous, calcareous and gravel. We found that the variation of macrophyte communities was determined by several habitat factors (mainly altitude, flow type, riverbed granulometry, conductivity and alkalinity), whereas the spatial factor was rather limited; further, the plant diversity was not reflected accurately by the European ecoregion approach

Macrophyte and macroinvertebrate patterns in unimpacted mountain rivers of two European ecoregions

The aim of the study was to compare the patterns of development of macrophytes and macroinvertebrates in different types of reference mountain rivers. The study is based on reference river sites surveyed throughout the mountains in Poland and Slovakia in two European ecoregions (9—Central Highlands, 10—The Carpathians). A wide range of environmental variables were estimated, including water chemistry, hydromorphology, geology, and the spatial factor. Based on the Jaccard index, macrophyte and macroinvertebrate variation was confirmed between four mountain and upland river types. It was found that the biological diversification is mainly influenced by geological and associated chemical factors. In the case of macroinvertebrates, additionally, the importance of the spatial factor was revealed (difference between ecoregions). Finally, the habitat preferences of various taxa were identified. It was found that extreme mountain conditions can sometimes distort bioindicative response, as was detected in the case of macroinvertebrates in the highest mountain sites. We concluded that consideration of two groups of organisms enables more comprehensive and reliable monitoring than assessment based on a single group, especially when standard bioindicative methods can be distorted by extreme local conditions

Wskaźniki jakości wody małego cieku leśnego odbierającego oczyszczone ścieki bytowe

Struga Kwilecka ma zlewnię całkowitą o powierzchni 48 km2 z dominacją terenów rolniczych i przepływa przez kilka jezior, w tym przez Jezioro Kwileckie. Analizowany odcinek odwadnia obszary zalesione. Badania zmian jakości wody Strugi Kwileckiej poniżej zrzutu oczyszczonych ścieków bytowych prowadzono w latach 2008––2011. Oczyszczalnia w Kwilczu posiada drugi stopień oczyszczania ścieków, które odprowadza poprzez staw sedymentacyjno-fakultatywny. Staw okresowo wpływa na podwyższenie stężeń fosforu w ściekach dopływających do badanego cieku. Pogorszenie jakości wody zaobserwowano szczególnie na stanowisku zlokalizowanym 100 m poniżej zrzutu. Na stanowiskach usytuowanych 350 i 700 metrów poniżej kolektora sytuacja poprawiała się pomimo niewielkich przepływów wody. Korzystne zmiany dotyczyły przede wszystkim wskaźników troficznych, takich jak fosforany rozpuszczone, fosfor ogólny, azot azotanowy, jak również przewodność elektrolityczna. Z uwagi na duże zacienienie koryta w cieku stwierdzono ubogi skład gatunkowy roślin wodnych (głównie trzcina pospolita) i minimalne powierzchnie pokryte przez inne taksony, w tym mszaki

Long-Term Changes in and Conservation Guidelines for Water Caltrop (<i>Trapa natans</i> L.) in Two Reservoirs in Poland

Climate change, worsening freshwater quality, and anthropogenic factors have caused water caltrop to lose approximately 80% of its habitat in Poland since the early 1980s. The presence of this plant species has substantially changed since the end of the 19th century. Our aim in this study was to examine the habitat and conservation status of Trapa natans in the Szumirad reservoir and Nowokuźnicki pond reserve in Poland and to indicate sources of potential hazards for the analyzed population. To achieve this aim, we spatially analyzed the changes in the total reservoir area, dynamics of species population, physico-chemical parameters of water, and climatic data. For the Szumirad reservoir, we observed substantial changes in water caltrop quantity and condition. For the Nowokuźnicki pond reserve, we found a serious threat to the Trapa habitat posed by the developing Nupharo–Nymphaeetum albae association, which is a strong competitor of nymphaeids. The obtained results indicated that surface waters localized in protected areas might play an important role in maintaining the population of water caltrop. On the basis of our analyses of selected populations, we emphasize that present protection procedures should be supplemented with the active protection of the species

Temporal and spatial variations of trophic status of a small lowland river

The research area was situated in Kujawskie Lakeland (central Poland), where agricultural landscape, arable lands, and improved grasslands prevail. River water samples for physico-chemical analyses were collected in the years 1999, 2006, and 2010, together with macrophyte data. All studied sites were localised in the rural landscape with insignificant impact of shading on the structure of aquatic taxa. The analysis of temporal changes in the taxonomic composition of macrophytes was performed with linear indirect PCA ordination. Evaluation of the trophic status of the Noteć River was performed using different macrophyte metrics and the chemical index of trophy. There were not significant temporal shifts of the trophic level of studied sites evaluated both using macrophyte metrics and hydrochemical index, but particular physico-chemical parameters like total phosphorus, soluble reactive phosphates, conductivity, and pH reaction showed statistically significant temporal changes. Significant difference of trophic states between sites localised below lakes and the others was observed for all years

Influence of selected environmental factors on macroinvertebrates in mountain streams

The objectives of our survey were: to analyze the structure of macroinvetebrate communities in mountain streams in national parks and Biosphere Reserves (Poland, the Slovak Republic), to determine the environmental factors that influence the structure of macroinvertebrate communities and to assess the stream habitats including the bank and channel features, any modifications, land use and channel vegetation. Our results showed that in addition to the conductivity, the altitude, stream gradient and the values of the HQA index that reflected more natural features in the channel and river corridor were most important. The River Habitat Survey (RHS) method reflects not only the morphology but also the relationships between habitat features and the structure of macroinvertebrate communities and it provides a more holistic approach to assessing the health condition of stream ecosystems. Headwater streams support unique macroinvertebrate taxa that are found nowhere else in a catchment and may also constitute refuges for in-stream biota. Some of the least water pollution-tolerant macroinvertebrate taxa were recorded