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.

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.

Action reducing the outfl ow of nitrates from agricultural sources to waters on the nitrate vulnerable zones in the catchment of the SamicaStęszewska river. The aim of the performed investigations was to assess the scope and effectiveness of actions undertaken on the Nitrate Vulnerable Zone (NVZ) in a catchment area with waters sensitive to agricultural pollution. The investigations on the catchment of the Samica Stęszewska river were conducted in 2005-2007. They included, among others: the estimation of the quality of surface waters, directions and the intensity of agricultural activity, applied agricultural practices, plans and balances of fertilization. The investigations showed that arable lands predominate the examined catchment area of the Samica Stęszewska river and agricultural activity contributed signifi cantly to water pollution. Many farms lacked buildings and the devices for proper storage of manures. The majority of farms realize intensive agricultural production, many of them specialise in swine breeding. High fertilization is complied on farms often and high livestock density. It is the reason of introducing the large quantities of nutrients to agro-ecosystems and causes the nutrient surpluses in balance. Farmers were well-acquainted with principles of good agricultural practice and declared the will of realization of actions introduced on vulnerable zones aiming at reducing nitrates from agricultural sources. The majority of farmers complied with recommendations of the Code of Good Agricultural Practice. No farm exceeded the quantity of 170 kg N·ha -1 in manures recommended in the Nitrates Directive, yet the level of fertilization on the catchment area was high.

In several countries around the world, agricultural land area exceeds 70% (Uruguay 82.6%, Kazakhstan 80.4%, Turkmenistan 72.0%, Great Britain 71.7%, Ukraine 71.6% and others). This poses a serious risk of dissipating nitrates into the aquatic environment in agricultural catchments. The aim of this study was to assess the impact of land use on water quality parameters in an agricultural catchment area. It was decided to select for analysis the catchment of the Orla River (river length of 88 km, catchment area of 1,546 km2). The catchment area is predominantly agricultural in character and its entire area has been declared as an agricultural nitrate vulnerable zone (NVZ). A total of 27 survey sites were selected on the main watercourse and its tributaries. Analyses were conducted in the years 2010–2012 to determine physical and chemical parameters of water (pH reaction, conductivity, dissolved oxygen, total nitrogen, organic nitrogen, ammonia nitrogen, nitrates, total and reactive phosphorus) as well as six macrophyte metrics of ecological status assessment (MIR, IBMR, RMNI, MTR, TIM, RI). The average values of most physico-chemical parameters of water quality repeatedly exceeded limits of good ecological status, both in the Orla River and its tributaries. As many as 18 survey sites were classified as moderate ecological status, five sites as poor and only four as good ecological status. The results indicate the impact of land use in the catchment on water conductivity. Differences were observed in the concentrations of biotic components in the main watercourse and its tributaries, and in water quality in the southern part of the catchment in relation to the rest of the study area. This is probably connected with a greater share of forests and surface waters in that area.

No abstract

The aim of this study was to assess the efficiency of the innovative SED-BIO system in limiting the inflow of pollutants to Jelonek Lake. The analyses were conducted in the Gniezno Lake District in Greater Poland (the western part of Poland). Physical and chemical analyses were conducted in the years 2016–2019. The results demonstrate that the system is highly effective in the reduction of such nutrients as nitrogen (NO3−—63%; NH4+—14.9%) and phosphorus (PO43−—19.3%). Although the presence of cyanobacteria was confirmed practically throughout the whole monitoring period of the system (2016), the specimens found in most samples were not toxigenic genotypes with a potential to produce microcystins. Microcystins (3 µg·L−1) were detected only once, immediately after the SED-BIO system had been installed in the river and pond, which demonstrates that this natural toxin was eliminated from the additional pool of contaminants that might be transported to Jelonek Lake.

Council Directive 91/676/EEC of 12 December 1991 [1], which is implemented in Poland, obliges the Member States of the European Union to take measures to prevent dissipation of nitrogen in surface and ground waters. One of the obligatory tasks is the establishment of sensitive water and nitrate-vulnerable zones (NVZ) in agricultural catchments. In 2013, the European Commission (EC) brought a complaint against Poland to the European Court of Justice (Case C-356/13) [2], in which Poland was accused of failing to reduce emissions of agricultural pollutants. The EC pointed out abuse in the determination of sensitive water and nitrate vulnerable zones and their serious underestimation. In 2012-2016 these areas occupied 4.46% of Poland.

Material and methods Agricultural statistics. Information about the structure of animal species and their abundance, structure of land use and crops, crop yield and fertilizer use are obtained with the practitioners development, agricultural activists, scribes and statistical studies 2. Analyzes were made for years and collected the most complete and accurate data. Nitrogen balance sheet. The correctness of the nitrogen management is calculated based on the field surface balance 3. Some of the elements of balance structure were significant only at certain times. Later, due to changes in agricultural techniques, but also introduced legislative acts, their share decreased or completely lost its importance. Nitrogen balance formula is as follows: