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The research was aimed at determining whether a pesticide tomb affects the ecological status of drainage ditches located in its vicinity as well as how it affects the diversity of the flora of the ditches and in which direction its effect on the surrounding environment is. In addition, the results of the study are a contribution to a comparative analysis of methods for macrophyte evaluation of watercourses used in Poland and to identify the possibilities of their application in investigations of artificial watercourses under the pressure of pesticides. Values of indices of the hydromorphological evaluation (HQA, HMS) were similar for all drainage ditches examined. This points to a negligible effect of the pesticide tomb on the hydromorphological characteristics of the analyzed watercourses. The pesticide tomb was found to affect the ecological status and floral diversity of the drainage ditches. The lowest values of macrophyte and diversity indices were recorded in the first and the second watercourse, whereas higher ones were in the third watercourse. Changes in the indices of ecological status and those of floral diversity observed in the watercourses examined show that the effect of the pesticide tomb on the surrounding ecosystem is consistent with topographic features and proceeds in a north-easterly direction. Both methods of the macrophyte evaluation of the ecological status of watercourses (MTR, MIR) yield different numeric values, yet their results are comparable in terms of the tendency of changes in the ecological status of the analyzed watercourses. In both methods, the highest rank was reported for the third watercourse. The MTR index diversifies the examined watercourses to a smaller extent than the MIR index. The MIR method is better under conditions of lowland Poland for the evaluation of the ecological status of artificial watercourses, as it enables stronger diversification of the ecological status of the watercourses examined due to a higher number of indicatory species.
Rivers and streams in cities are treated as urbanised watercourses because of their significant transformation. Their load, channeling and incorporation into the water-sewerage infrastructure are often so considerable that such watercourses can hardly be recognised as an intrinsic component of surface waters. Anthropopressure, as reflected in quantitative and qualitative degradation caused by flow regulation and economic development in the drainage basin area, makes evaluation of the impact of human activity on the aquatic environment somewhat difficult. Based on the recommendations of the Water Framework Directive, an attempt has been made to assess the ecological state of selected tributaries of the Prądnik-Białucha River within the Krakow Conurbation. Aquatic environment sampling of the Sudół Dominikański (Rozrywka) watercourse was performed (September 2005) in order to determine some physicochemical, chemical and biological parameters, paying particular attention to macrophytes. The parameters measured on site: pH, electrolytic conductivity and Eh of water and bottom sediments, and sozological observations, were subjected to analysis. In the laboratory, concentrations of heavy metals, both in water and in solid particles (sediments and suspended matter) and anions in water were determined. The environmental state of the Sudół Dominikański watercourse was compared with that in the area of the Prądnik-Białucha River valley, for which an assessment had been conducted in the previous year (September 2004).
The European Water Framework Directive (WFD) requires all inland and coastal waters to reach “good ecological status” by 2015. The good ecological status of shallow lakes can be characterised by clear water dominated by submerged vegetation. The ecological response of shallow lakes on nutrients largely depends on morphological and hydrological features, such as water depth, retention time, water level fl uctuations, bottom type, fetch etc. These features determine the “critical nutrient load” of a lake. When the actual nutrient load of a lake is higher than the critical nutrient load, the ecological quality of this lake will deteriorate, resulting in a turbid state dominated by algae. Climate change might lead to changes in both environmental factors and ecosystem response. This certainly will have an effect on the ecological status. As an illustration the results of a multidiscipline study of a shallow peaty lake (Loenderveen) are presented, including hydrology, geochemistry and ecology. Ground- and surface water fl ows, nutrient dynamics and ecosystem functioning have been studied culminating in an application of the ecological model of the lake (PCLake). Future scenarios were implemented through changing precipitation, evaporation and temperature. Climate change will lead to higher nutrient loads and lower critical nutrient loads. As a consequence lakes shift easier from clear water to a turbid state.
This study focused on the phytoplankton and environment relationships as well as on the ecological and trophic conditions of lakes inhabited by coregonid fish. Studies were carried out in deep and stratified vendace-type lakes called Lake Pluszne and Lake Łańskie (the Olsztyn Lake District, north-eastern Poland) in 2007-2008. Ecological and trophic conditions were determined on the basis of the phytoplankton multi-metric PMPL and Trophic State Index. Both lakes were characterized by a similar thermal and mictic regime, with the occurrence of hypolimnetic oxygen deficits. They were classified as hydrocarbonate-calcium type and medium-sized eutrophicated water bodies. According to the integrated trophy assessment, proposed in this research, the final Trophic State Index TSIAV indicated meso-eutrophy of both lakes, although the phytoplankton-based PMPL indicated that the ecological potential in Lake Łańskie was good and less than good - due to large cyanobacteria biomasses - in Lake Pluszne. The actual loads of phosphorus and nitrogen significantly exceeded permissible levels, especially in Lake Łańskie (5-fold at the most of the P content), at similar morphometric and sedimentation conditions in both lakes. However, more intensive water-exchange rate and more favorable conditions for phosphorus runoff in Lake Łańskie could limit the phytoplankton growth, especially cyanobacteria. Summing up, better oxygen conditions and less abundant phytoplankton suggested that Lake Łańskie had more suitable conditions for coregonids during the surveyed period than Lake Pluszne, where the vendace biomass has recently decreased drastically.
One year qualitative and quantitative study of communities of three major taxonomic groups has been carried out at test panles placed in the upper infarlittoral zone of coastal area of Vela Luka Bay, Croatia. A list of 44 taxa was recorded. Chaetomorpha sp., Ulva sp., Fosliella farinosa, Sphacelaria cirrosa, Polysiphonia scopulorum were the most frequent dominant taxa. Among 27 algal taxa with noticeable presence only three were classified as ESG (Ecological State Groups) I. Low diversity and species richness together with massive presence of the green algae (as Ulva sp.) and negligible presence of ESG I taxa, may lead to erroneous conclusion that Vela Luka Bay is eutrophicated area. Low values of biomass and R/P (Rhodophyceae by Phaeophyceae ratio) Index together with dominance of Phaeophyta also support conclusion that there is no negative impact of nutrient enrichment on macrophyta fouling community in Vela Luka Bay.
This paper outlines the Phytoplankton Multimetric for Polish Lakes (PMPL) – an ecological status assessment method which can be used to implement the European Water Framework Directive (EC, 2000). The PMPL includes abundance parameters of phytoplankton: the metrics: “chlorophyll a”, “total biomass” while the taxonomic composition is partly evaluated by the metric “biomass of cyanobacteria”. All of these three single metrics as well as the final PMPL index values are the same scale and range from 0 to 5. The PMPL can be transformed to a normalized Ecological Quality Ratio (EQR) range from 0 (the worst status) to 1 (the best status). The PMPL method differentiates “stratified” and “unstratified” lake types as well as subdivisions into lakes characterized by a high (>2) or low (<2) lake volume-to-catchment area ratio (VQ). The metrics used and the PMPL index respond to eutrophication pressure expressed by total phosphorus and total nitrogen concentration, the significance of the relationships depends on the tested parameter and the abiotic type of lake. From among the single metrics, the metric “chlorophyll a” was usually found to reveal the strongest significant correlation to both total phosphorus and total nitrogen (Spearman`s coefficient varied from –0.41 to –0.75 and from –0.34 to –0.56, respectively). The weakest correlation with nutrients was noted for metric “biomass of cyanobacteria” (R=–0.13 to –0.62). The PMPL correlated best with TP and TN in unstratified lakes (R=–0.49 to –0.70). The testing of the PMPL index shows a statistically important distinction between Good/Moderate ecological status and confirmed designated boundaries of High/Good and Good/Moderate states.
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