Iga Lewin

Drivers of macrophyte development in rivers in an agricultural area: indicative species reactions

The ecological drivers of macrophyte development in a lowland agricultural area were tested based on a 2008 survey on the Wkra River catchment. Our survey was carried out in the rivers of an agricultural area with relatively high concentrations of both nitrates and phosphates in the water. By using the Polish macrophyte method, we were able to calculate several botanical metrics. Canonical ordination analyses used to relate biological data to environmental variables such as physical and chemical parameters of water, surface water velocity or river width, were carried out using CANOCO for Windows. Redundancy analysis (RDA) showed that pH and alkalinity were the parameters best correlated with the distribution of macrophytes and values of macrophyte indices. The recorded values of the Macrophyte Index for River in the Wkra River and its tributaries reflected their good and moderate ecological status (the Water Framework Directive scale). Despite the fact that nutrient concentrations in the water were relatively high and that most of the sites represented eutrophic conditions, the results of this survey showed that non-nutrient parameters may play an important role in explaining aquatic plant occurrence in rivers that have been subjected to eutrophication.

THE GASTROPOD COMMUNITIES IN THE LOWLAND RIVERS OF AGRICULTURAL AREAS - THEIR BIODIVERSITY AND BIOINDICATIVE VALUE IN THE CIECHANOWSKA UPLAND, CENTRAL POLAND

Lowland river degradation of agricultural areas is a problem not only in Poland but also in Europe and worldwide. The objectives of the present study were to determine the biodiversity of the gastropod communities in lowland rivers under the impact of agriculture, the relationship between gastropod communities and environmental factors, and to estimate the usefulness of the gastropod communities as an indicator of water quality. Four rivers that flow through an agricultural area were investigated. A high value of chlorophyll a, a low value of total dissolved oxygen and a high concentration of phosphates or total phosphorus and organic matters are present in the rivers. Gastropod communities in the rivers of the Ciechanowska Upland are influenced by bottom sediments, the physical and chemical parameters of water, and the abundance of macrophytes, which are typical of eutrophic water. In the rivers of the Ciechanowska Upland, gastropods can be biological indicators of dissolved oxygen in water – Viviparus viviparus (Linnaeus, 1758) and Lymnaea peregra (O. F. Müller, 1774) can be indicators of anthropopressure. The values of diversity indices varied from site to site, but did not decrease along the river.

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 features, 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.

Occurrence of the Invasive Species Potamopyrgus antipodarum (Prosobranchia: Hydrobiidae) in Mining Subsidence Reservoirs in Poland in Relation to Environmental Factors

ABSTRACT The New Zealand mud snail, Potemopyrgus entipoderum (Gray, 1843), is recognized as a successful invader of aquatic environments in Australia, Europe, Japan, North America and western Asia. To date, a long-term survey on the occurrence of P. entipoderum (including its initial dispersal, establishment and integration) both in mining subsidence reservoirs and an adjacent river in Poland has not been carried out. The objectives of this survey were to analyze the environmental factors that influence the occurrence of P. entipoderum in relation to mollusc communities in mining subsidence reservoirs affected by coal mine output in terms of initial dispersal and the establishment of self-sustaining populations in the new habitat, to analyze annual variations in the densities and shell height of P. entipoderum in relation to the different types of substratum, and to determine the number of embryos in the brood pouch per female at the integration stage (phase). During the years 1993–2008, seven mining subsidence reservoirs that have different water sources and a part of the Mleczna River were investigated. From 1997 to the present, P. entipoderum has been eudominant in mollusc communities both in coal mining subsidence reservoirs, which receive water from the mine dewatering system and in the river. Based on a redundancy analysis (RDA), the conductivity of water and the concentration of nitrates were the parameters most associated with the distribution of mollusc species, including P. entipoderum. The relation between the species and these environmental variables was statistically significant. These results do not suggest that the integration of P. entipoderum has negatively influenced the occurrence of other mollusc species either in the mining subsidence reservoirs or in the Mleczna River, probably due to smaller densities compared with a survey of the western United States, where P. entipoderum has a strong influence on aquatic ecosystems and restricts the occurrence of native macroinvertebrates. Potemopyrgus entipoderum has established itself in these mining subsidence reservoirs and is integrated into the local biota without any major negative effects (e.g., extirpations) on the communities being invaded.

The Importance of the Mining Subsidence Reservoirs Located Along the Trans-Regional Highway in the Conservation of the Biodiversity of Freshwater Molluscs in Industrial Areas (Upper Silesia, Poland).

The objectives of the survey were to analyse the structure of the mollusc communities in the mining subsidence reservoirs that were created as a result of land subsidence over exploited hard coal seams and to determine the most predictive environmental factors that influence the distribution of mollusc species. The reservoirs are located in urbanised and industrialised areas along the Trans-Regional Highway, which has a high volume of vehicular traffic. They all have the same sources of supply but differ in the physical and chemical parameters of the water. In total, 15 mollusc species were recorded including four bivalve species. Among them Anodonta cygnea is classified as Endangered according to the Polish Red Data Book of Animals and also as Near Threatened according to the European Red List of Non-marine Molluscs. Eleven of the 15 mollusc species are included on the European Red List of Non-marine Molluscs as Least Concern. Conductivity, pH and the concentration of calcium were the parameters most associated with the distribution of mollusc species. Canonical correspondence analysis showed that Potamopyrgus antipodarum, Radix balthica, Physella acuta, Gyraulus crista and Pisidium casertanum were associated with higher conductivity and lower pH values. A. cygnea, Anodonta anatina and Ferrissia fragilis were negatively influenced by these parameters of the water. The results of this survey showed that the mining subsidence reservoirs located in urbanised and industrialised areas provide refuges for rare and legally protected species and that they play an essential role in the dispersal of alien species as well.

Rare, threatened and alien species in the gastropod communities in the clay pit ponds in relation to the environmental factors (The Ciechanowska Upland, Central Poland)

The objectives of the present survey were to formulate a zoocenological analysis of the gastropod communities in clay pit ponds, as well as to determine the relationships between the gastropods and their environments, and to evaluate the water habitats in terms of their ecological-conservation value. The physical and chemical parameters of water, gastropod species and macrophytes occurring in the ponds indicate mesotrophic conditions. Principal Component Analysis (PCA) reveals a correlation between gastropod density and nitrates, a correlation between gastropod density and alkalinity, and additionally shows a correlation between gastropod density and chlorides. The pond surface area, nitrates, chlorides concentrate, alkalinity, and substratum have all affected these gastropod communities. The occurrence of the first permanent population of Ferrissia clessiniana (Jickeli, 1882) was recorded in Poland. Valvata naticina Menke 1845 has become a critically rare species (CR) due to the pollution of water environments. Five other species, e.g. Anisus vorticulus (Troschel, 1834) and Planorbis carinatus O.F. Müller, 1774 are recorded on the Polish Red List of Species. The clay pit ponds of the Ciechanowska Upland, because of their distinctive environmental features, provide a refuge where a number of rare, threatened and alien gastropod species live.

The influence of the landscape structure within buffer zones, catchment land use and instream environmental variables on mollusc communities in a medium-sized lowland river

The world’s freshwater molluscan fauna is facing unprecedented threats from habitat loss and degradation. Declines in native populations are mostly attributed to the human impact, which results in reduced water quality. The objectives of our survey were to analyse the structure of the mollusc communities in a medium-sized lowland river and to determine the most important environmental variables at different spatial scales, including landscape structure, catchment land use and instream environmental factors that influence their structure. Our survey showed that a medium-sized river, that flows through areas included in the European Ecological Natura 2000 Network Programme of protected sites, provides diverse instream habitats and niches that support 47 mollusc species including Unio crassus, a bivalve of Community interest, whose conservation requires the designation of a special conservation area under the Habitats Directive Natura 2000. This survey showed that mollusc communities are impacted by several environmental variables that act together at multiple scales. The landscape structure within buffer zones, catchment land use and instream environmental variables were all important and influenced the structure of mollusc communities. Therefore, they should all be taken into consideration in the future restoration of the river, future management projects and programmes for the conservation of biodiversity in running waters. The results of this study may be directly applicable for the rehabilitation of river ecosystems and are recommended to stakeholders in their future decision concerning landscape planning, monitoring species and their habitats, conservation plans and management in accordance with the requirements of sustainable development.

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.

Influence of selected environmental factors on macroinvertebrates in mountain streams

Abstract 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.