Barbara Nagengast

The Influence of the Spatial Structure of Hydromacrophytes and Differentiating Habitat on the Structure of Rotifer and Cladoceran Communities

Research on the similarity of zooplankton in various stands of water vegetation, including rushes (Typha angustifolia), nymphaeids (Nymphaea alba) and submerged macrophytes (Charahispida, C. tomentosa, Myriophyllumverticillatum and Utricularia vulgaris) was carried out on the shallow Wielkowiejskie lake (Poland). The analysis of the similarity of the Rotifera community revealed the strongest relationship between the Myriophyllum and Chara tomentosa beds, with C. hispida attaching them. A second pair of habitats was represented by Typha and Nymphaea stands. Cladocerans revealed the greatest similarity between both zones of Chara. Additionally, two more pairs of habitats were distinguished – Typha and Nymphaea and also Utricularia and Myriophyllum. In most cases, the Shannon-Weaver values were high among macrophyte stations. Forward stepwise regression revealed that the length of Nymphaea stems was a single negative predictor determining the Cladocera densities. The water lily stand possessed the richest pelagic community of zooplankton and had the highest cladoceran diversity index. In accordance with CCA-ordination, out of the environmental variables, the macrophyte stem length and the concentration of Ptot were the strongest predictors in determining the distribution of particular species of the zooplankton community. Mainly pelagic species displayed preferences towards physical parameters of habitat, which is manifested in their greater affinity to a denser spatial structure of macrophyte substratum. The similarity of zooplankton communities in Wielkowiejskie lake was based on the characteristic architecture of particular macrophyte species, where the plant length was the strongest predictor. Moreover, the character of the zooplankton communities was also influenced by the concentrations of chlorophyll ‘a’ and the chemical variables, with the strongest impact of Ptot, of periphyton received from a particular macrophyte habitat and from water filling the spaces between plant stems.

The role of aquatic macrophytes in microhabitatual transformation of physical-chemical features of small water bodies

The paper presents the results of an examination of the phycical-chemical parameters of water together with an analysis of the chlorophyll a concentration of 12 small water bodies situated within urban and suburban areas of the city of Poznan (mid-west Poland)—typical mid-forest, strongly anthropogenically modified in the urban landscape, strongly antropogenically modified in an agricultural area and clay-pits. There were zones of open water (Unvegetated Zone) as well as zones of rush and aquatic vegetation (Vegetated Zone) distinguished in the examined ponds. The influence of the rush vegetation, nymphaeids and elodeids on the abiotic parameters of an aquatic environment was examined. Water samples were taken during the summer of 2004 from 12 stations within the open water and 24 within macrophytes. The plant matter was randomly collected in triplicate from the central part of the vegetated stand. The influence of macrophytes on the abiotic features of water was estimated using the parameter of the plant length (cm l−1) and the plant biomass (g l−1). In the studied ponds 12 aquatic macrophyte communities were distinguished. A salient feature of submerged macrophytes was a great density of plant stems along with considerebly low biomass, however, the rush vegetation (Phragmitetum communis, Typhetum latifoliae) when compared to nymphaeids (Polygonetum natantis, Potametum natantis) and elodeids (Potametum lucentis) was characterised by lower stem densities and higher biomass. The water bodies were alkaline and of pronounced hardness. In most of them high trophy conditions were found with especially high concentrations of phosphorus (96 μg l−1 on average). There was significant differentiation in the water chemistry (mainly in respect to mineral compounds) between the Vegetated and Unvegetated Zones as well as between particular aquatic macrophyte communities.

Zooplankton community structure within various macrophyte stands of a small water body in relation to seasonal changes in water level

Zooplankton community structure within various macrophyte stands of a small water body in relation to seasonal changes in water level Different morphological features of particular water bodies, physical and chemical factors of their waters and sediments will have an impact on the development of specific aquatic vegetation types, which in turn will affect the creation of specific communities of plankton organisms. Therefore the aim of this study was to analyse the quantity and quality changes of macrophyte structure in relation to the lowering of the water level. Furthermore, the relationship between zooplankton community densities and environmental parameters was studied. Another aspect of the study was to investigate the similarity of the zooplankton communities of particular sampling stations in the three examined seasons. The study was carried out on Dąbrówka water body, a shallow and macrophyte-dominated pond, situated 10 km west of Poznań, Wielkopolska region, western Poland. The examination was conducted in the three seasons: spring, summer and autumn. The results revealed that during one vegetative period, including three seasons — spring, summer and autumn, three different layouts of aquatic vegetation were obtained, which reflected a significant transformation in the macrophyte cover. Along with the lowering of the water level the structural changes, especially in the case of submerged vegetation were recorded, which in each season was represented by different dominating species. Only three significant correlations between zooplankton densities and environmental factors observed. Negative relationship concerned total nitrogen and two positive related to biometric parameters of the macrophyte habitat (plant biomass plant stem volume). The plant biomass was a predictor of cladoceran abundance and plant stem volume referred to rotifers, which may reflect the complexity of the aquatic plant habitat, indirectly relating to the effectiveness of the macrophyte stand as anti-predator refuge. The analysis of the similarity of the zooplankton communities of particular sampling stations in the three examined seasons did not reveal any clear relationship, either in relation to a particular season or a sampling station. The participation of eutrophic species was highest in the spring and lowest during the autumn season. The open water zone possessed the highest participation of these species compared to the macrophyte zones.

Can popular systems of trophic classification be used for small water bodies

Can popular systems of trophic classification be used for small water bodies? The aim of the study was to evaluate the trophic conditions of the waters of twelve small ponds based on the analysis of their physical and chemical parameters according to Carlsons Trophic State Index and OECD. Great differentiation in the trophic status of ponds located in different varieties of landscape was observed and ranged from mesotrophic to weak eutrophic conditions in mid-forest ponds and clay-pits, eutrophic conditions in pastoral ponds, and hypertrophic conditions in urban water bodies. Throughout the analysis, a number of limitations in the classification methods of trophic conditions in the examined water bodies were noted. The specific problems were the shallow depth of ponds, which often corresponded with the depth of the Secchi disc transparency, or the complete overgrowing of the pond water column by macrophytes.

The epiphytic communities of various ecological types of aquatic vegetation of five pastoral ponds

Five small water bodies located within the agricultural region of Wielkopolska (west Poland) underwent investigation. Periphyton samples were collected from various macrophyte habitats representing rush vegetation (in five water bodies), submerged aquatic plants (in three) and nymphaeids (in one): Palędzie — Ceratophyllum demersum, Potamogeton crispus, Typha latifolia; Batorowo — Phragmites australis; Piotrowo — Potamogeton natans, Ceratophyllum submersum, Typha latifolia; Tarnowo Podgórne — Typha latifolia; Dąbrówka — Zannichellia palustris, Potamogeton pectinatus, Phragmites australis.The main goal of the study was to determine the composition and abundance of the periphytic communities inhabiting various types of rush and water vegetation of five water bodies located within a mid-field landscape area.Diatoms such as Achnanthidium minutissimum, Amphora ovalis, Cocconeis placentula orNavicula cincta revealed significantly higher densities in the zone of elodeids, while green algae prevailed among nymphaeids. As a result of this study it was found that the epiphytic algae were characterised by much lower diversity in respect to a specific water body, though much greater diversity was observed in its relation to the type of substratum. Two types of habitats were distinguished — the first of simple build (helophytes and nympheids) and the second containing the complicated architecture of plant stems (elodeids).

Macrophyte biometric features as an indicator of the trophic status of small water bodies

Abstract The aim of the study was to determine whether biometric features of plants collected from single-species phytocoenoses developing in ponds can be used to describe habitat conditions of these water bodies. The biometric measurements were carried out in 148 field small water bodies at a total of 198 sites. The length of plants, their dry biomass, and volume of plant shoots were analyzed, converted to 1000 dm3 of water. The biometric measurements showed very large differences in individual parameters of different macrophyte species. The biggest differences were found in the length of elodeids and helophytes (from 1 cm to > 900 cm), regardless of trophic conditions. Although the Polish flora is dominated by plants having a wide ecological range, there are species whose parameters correspond to specific habitat fertility. The highest biometric parameters were found for Ceratophyllum submersum, Sparganium erectum, Typha latifolia and Schoenoplectus lacustris in ponds characterized by increased trophic conditions. In contrast, Myriophyllum spp. alone showed a negative correlation with trophic state indices. The trophic effect on the studied parameters becomes more apparent for species with optima in fertile water bodies. The parameters of Ceratophyllum submersum can be considered as the trophic state index (TSI).

Relationship between plankton assemblages and habitat characteristics of stands of Typha angustifolia and Chara hispida in Lake Wielkowiejskie

Relationship between plankton assemblages and habitat characteristics of stands of Typha angustifolia and Chara hispida in Lake Wielkowiejskie The results of investigations performed in Lake Wielkowiejskie showed the influence of macrophyte architecture, understood as plant density, on the structure of plankton communities as well as the habitat preferences of particular species in both seasonal and spatial aspects.

The impact of biometric parameters of a hydromacrophyte habitat on the structure of zooplankton communities in various types of small water bodies

The impact of biometric parameters of a hydromacrophyte habitat on the structure of zooplankton communities in various types of small water bodies Hydromacrophyte habitats, which can differ in a multiplicity of biometric parameters, are among the most important factors affecting zooplankton community structure. The main goal of this work was to determine the impact of plant habitat parameters expressed by density, biomass, and plant volume along with chemical features on the composition and dynamics of rotifer and crustacean communities. A number of small water bodies of different origin (12) located in different catchment areas of the Wielkopolska region were analyzed. It was found that helophytes and nymphaeids had the highest biomass and the lowest stem density, while elodeids were of the lowest biomass and the greatest stem density. Similarity analysis confirmed this distribution of biometric parameters among particular ecological groups of macrophytes. The greatest numbers of zooplankton were noted among vegetated zones, which supports the idea of zooplankton using macrophytes as anti-predator refuge. Based on the study of a total of 23 plant stands, it was found that macrophyte biomass and the density of the plant habitat were the strongest predictors of three biometric parameters of zooplankton abundance.

Translocation of Nuphar lutea (L.) Sibth. & Sm. from the A2 road near Nowy Tomyśl (Poland) into alternative sites

Translocation of Nuphar lutea (L.) Sibth. & Sm. from the A2 road near Nowy Tomyśl (Poland) into alternative sites A translocation of Nuphar lutea (L.) Sibth. & Sm. was made from its primary location in Prądówka, situated in the path of the construction site of the A2 motorway, into replacement biotopes. All rhizomes were taken out of the water and used to prepare cuttings. These were divided into three approximately homogeneous groups. Each group was introduced into different replacement water bodies with environmental conditions that resembled those of the biotope in the Prądówka site. Two of the water bodies were fish ponds. A third was a so called ‘ecological water body’ (settling pond, settling basin) that collected fall effluents delivered from the surface of motorway. The results of the examination of the physical-chemical features of water and bottom sediments from the Prądówka peat pit, two fish ponds and four settling basins are presented in the article. Biological and autecological features of the species Nuphar lutea, which are significant from the aspect of the growth of the seedlings within the alternative sites, have been discussed. A year after translocation it was observed that in the case of fish ponds, 83% and 75% of the introduced plants survived, while in the settling basin only 50%. A conservation project was undertaken by the investor in order to compensate for the negative effects of the A2 motorway within the area of the European Ecological Natura 2000 Network.