The aim of study was to evaluate the richness and distribution of the aquatic macrophytes in ponds. . Studies were carried out in July 2013 and July 2014 on the six largest and oldest ponds (functioning since the First World War) in the Łęczna-Włodawa Lake District – Sosnowica ponds. Studies have shown that despite the fishing use of ponds, they can provide valuable habitat for aquatic plants biodiversity. Distribution of plants in the ponds was typical mosaic. Phytolittoral often developed from one bank to another. Macrophyte beds occupied a significantly large percentage of the studied pond areas. Emergent macrophytes were dominant group of macrophytes in investigated ponds.

The results of the study of the macrophytes of the rivers Turia, Vyzhivka and Tsyr, the right-bank tributaries of the upper reaches of the Pripet River, are presented. The species composition of aquatic and coastal aquatic vascular plants was investigated during the vegetation seasons of 2018 and 2019 at 9 observation points located along the rivers from the source to the mouth. The most numerous species composition, 57 species, was found in the Turia River, 36 in the Vyzhivka River, and 28 species were identified in the Tsyr River. The macrophyte index for rivers (Pol.: makrofitowy indeks rzeczny – MIR) was determined from the results, and the ecological state of the rivers was assessed according to the methodology of the macrophyte assessment of rivers (Pol.: makrofitowa metoda oceny rzek – MMOR). The investigation showed that water quality in the Turia River on sites No. 1, 3 and 4 belongs to class III, satisfactory category. The surface water quality on site No. 2 of the Turia River belongs to class II, a good category. The water quality in the Vyzhivka River on all test sites belongs to class II, a good category, which testifies to favourable ecological conditions for the development of higher aquatic plants along the whole course. The water quality in the Tsyr River on test site No. 8 (Kamin-Kashyrskyi, upper course) corresponds to class II, good category. On test site No. 9 (middle course), the quality of surface waters of the Tsyr River worsens to the class III, satisfactory category.

The relationships between epiphytic fauna and habitat conditions were studied in three oxbow lakes of Wieprz River (eastern Poland). Fauna associated with macrophytes showed low species richness (range 8–11 taxa dependently on site and season) usually observed in lakes of high water trophy. Densities of fauna were high (mean 71–5250 ind. 100 g DW-1), typical for shallow lakes with well developed submerged vegetation. In the domination structure prevailed Gastropoda (relative abundance 23–100%) and Chironomidae (relative abundance 8–87%). Re-dundancy analysis showed the significance of four environmental variables – temperature, dis-solved oxygen, Ptot and P-PO4 as determinants of abundance of epiphytic fauna.

The role of two submerged macrophyte species (Ceratophyllum demersum and Potamogeton pectinatus) as biological factor affecting concentrations of P and chlorophyll a concentrations was tested under laboratory conditions. In general, after four weeks exposition, the significant reduction of TP, P-PO4 and chlorophyll a was observed in all experimental variants (aquaria with P. pectinatus, C. demersum and P. pecinatus + C. demersum), but the highest decrease of phosphorous compounds (TP, P-PO4) was noted in aquarium with C. demersum, whereas the highest decline of chlorophyll a concentration (biomass of phytoplankton) was observed in aquarium with C. demersum + P. pectinatus. Together with the reduction of chemical parameters the biomass of macrophytes as well mean length of plant shoots significantly increases. The highest growth of shoots and biomass showed C. demersum.

Due to the significant role of macrophytes in the functioning of lake ecosystems studies have been undertaken to examine whether mutual dependence is present within emergent, floating-leaved, and submerged aquatic macrophytes. The study included 5 small lakes from Polesie Lubelskie region. The research included: qualitative analysis of macrophytes (area occupied by macrophytes, composition, range of individual plant groups of occurrence), quantitative analysis of macrophytes (biomass of macrophytes inhabiting the lake), analysis of distribution as well as characteristics diversity of shoreline and surrounding land use. Because of differences in the environmental conditions, mostly light availability, usage of buffer zone, among the three macrophyte groups, changes in biomass were analyzed in this work suggests that complementarity not competition drive the community. This phenomenon seems to occur only in macrophyte lakes where all three groups are present and the surrounding buffer zones remain natural. In lakes where one of the three groups of macrophytes were missing, it is likely that the ecological roles are fulfilled by other plant groups, such as phytoplankton. The studied lakes represent both phytoplanton and macrophyte type of lakes.

Four small (surface area: 0.4-2.3 ha), but relatively deep (max. depth: 6.5-7.8 111) man made reservoirs, created between 1979 and 1988 on recultivatccl waste heap of former sulphur mine in Machów (N 50°31'35": E 21°37'51")_ were studied in summer and autumn 2003. In autumn one lake - Kacze was not mixed down to the bottom, which could point to its meromixis. The other lakes were found to be dimictic. In all the lakes high values of total hardness, conductivity, chlorides, sulphides and low amounts 01· total phosphorus and nitrogen were found. Both phytoplankton and hydrornacrophyte communities were poorly developed. Considerable amounts or green-yellow bacteria were also noted in plankton The water chemistry as well as quantity and quality of plant communities reflect the chemical composition of loam soils which constitute the waste heap.

The constructed wetland integrated with microbial fuel cell (CW-MFC) has gained attention in wastewater treatment and electricity generation owing to its electricity generation and xenobiotic removal efficiencies. This study aims to use the CW-MFC with different macrophytes for domestic wastewater treatment and simultaneously electricity generation without chemical addition. The various macrophytes such as Crinum asiaticum, Canna indica, Hanguana malayana, Philodendron erubescens, and Dieffenbachia seguine were used as a cathodic biocatalyst. The electrochemical properties such as half-cell potential and power density were determined. For wastewater treatment, the chemical oxygen demand (COD) and other chemical compositions were measured. The results of electrochemical properties showed that the maximal half-cell potential was achieved from the macrophyte D. seguine. While the maximal power output of 5.42±0.17 mW/m2 (7.75±0.24 mW/m3) was gained from the CW-MFC with D. seguine cathode. Moreover, this CW-MFC was able to remove COD, ammonia, nitrate, nitrite, and phosphate of 94.00±0.05%, 64.31±0.20%, 50.02±0.10%, 48.00±0.30%, and 42.05±0.10% respectively. This study gained new knowledge about using CW-MFC planted with the macrophyte D. seguine for domestic wastewater treatment and generation of electrical power as a by-product without xenobiotic discharge.

The study included mesotrophic Lake Piaseczno, located in the Łęczna-Włodawa Lake District. The aim of the study was to evaluate changes of water vegetation of a mesotrophic lake subjected to strong recreational pressure. Specifically we sought to better understand which natu-ral landscapes and anthropogenic developments stimulate or impede macrophyte development and spread. The study was conducted in July in 1997, 2007 and 2017 in three transects: the peat-bog (northern part of the lake), the recreational area (southeast part) and the agricultural area (east). The phytolittoral zone was analyzed from the shoreline to the maximum range of macrophytes occurrence. The study included all groups of macrophytes. Macrophytes in the mesotrophic Lake Piaseczno are still subjected to successive changes. Clearly increased diversity among emergent macrophytes, while a group of submerged macrophytes decreased. The largest changes among analyzed groups of macrophytes occurred in recreational and agricultural transects. Macrophytes have increased the range of occurrence, which may be due to hydrological changes associated with raising the overall water level, thus with increasing the area of the littoral. Impoverishment of diversity among elodeids shows the processes associated with the increase in Lake trophy.

The aim of this study was to analyze the influence of water movement on both qualita-tive and quantitative occurrence of macrophytes in lakes. We studied four lakes differentiated in respect of water supply (two flow and two inflow).The investigation included: determination of the buffer zones of lakes, analysis of land use forms and layout of the buffer zone, floristic charac-teristic of lakes littoral, characteristic of phytolittoral types, analysis of physical and chemical parameters of lakes. The buffer zone of the flow lakes was dominated by farmland, but there was no land meadow. In the inflow lakes co-dominated fields and forests in the buffer zone. The in-flow lakes characterized by greater species diversity, density and biomass of emergent macro-phytes. In all investigated lakes, in the zone of water supply, analyzed features of macrophytes, and selected chemical parameters of water, reached the highest value.

According to the general classification of shallow eutrophic lakes, two alternative types are distinguished: phytoplankton-dominated and macrophyte-dominated lakes. The latter type is rare and currently endangered by human activity. In order to determine the effect of reduced inflow of surface water by an earth dyke on the lake trophic state, certain biological and physico-chemical parameters were evaluated. This work focuses on two lakes of similar morphometric characteristics situated in the agricultural landscape. The effect of the earth dyke on the trophic state was positively verified. The lake situated in the catchment basin, in which the inflow of surface water was reduced, was defined as meso-eutrophic, with a small amount of phytoplankton and high water transparency. The reference lake was highly eutrophic, with low water transparency and a large amount of phytoplankton. The water body surrounded by the earth dyke was macrophytes dominated (65% of the lake area), whereas the reference lake was a phytoplankton-macrophyte type (42% of the lake area). The trophic evaluation of a lake can be underestimated because of a significant amount of biogenic compounds accumulated in plant tissues. Thus, the values of Carlson’s indices in macrophyte-dominated lakes may not account for the total amount of nutrients in the water body.

The results of a research into the scale and consequences of the degradation of aquatic ecosystems in Ukrainian Polesie have been detected in article, and the areas of increased anthropogenic pressure have been identified which greatly affect the condition and number of aquatic macrophytes. The biodiversity of sites with different anthropogenic load was evaluated using the biodiversity criteria. In the research, the structural and functional features of macrophytic species diversity within Teteriv River ecological corridor as a typical river landscape of Ukrainian Polesie were determined and described, the floristic composition was determined. Within the ecological zones, the number of species and their projective coverage in areas with different anthropogenic pressures within Teteriv River ecological corridor were determined. The basic criteria for the implementation of deferred biomonitoring based on the analysis of the dynamics of the spe-cies composition of the phytocoenoses of Teteriv River ecological corridor on the indicators of ecological stability and plasticity using the species-specific criteria, are: Margalef species richness index, Sørensen–Dice index, Shannon diversity index, Simpson’s index, and Pielou’s evenness index. Based on the results, correlation dependencies have been constructed, which will allow to obtain data on the stability of the development of aquatic ecosystems according to the data of species surveys. Interconnections between biodiversity indicators and indicators of surface water quality within the Ukrainian Polesie were found; they are the fundamental component of a long-term monitoring of the stability in the development of aquatic phytocenoses.