Periphyton was cultured and its phytoplankton communities were identified based on morphological features. This included 24 genera belonging to the 6 classes. Highest number of genera was found in Bacillariophyceae followed by Cyanophyceae and Chlorophyceae. Whereas a single genus was documented from class Euglenophyceae, Ulvophyceae and Xanthophyceae. Hence, the study is quite handy for the id...

Growing concern over the ecological consequence of phosphorus (P) enrichment in freshwater wetlands has elicited considerable debate over the concentration of water column P associated with eutrophication. In the oligotrophic Everglades, the displacement of native communities by enriched ones is widespread and has occurred at sites experiencing only minimal elevations in P input. To help define...

The effects of multiple experimental floods in the same year on the ecology of a river (River Spöl) below a large reservoir were investigated. In the flood year (2000), three floods of different magnitude (10 m/s on 15 June, 25 m/s on 5 July, and 10 m/s on 10 August) were implemented, each lasting 7–8 h. Regulated baseflow discharge was maintained at less than 2.5 m/s. Samples of macroinvertebr...

In Neotropical streams, benthic sediment affects community structure and may impose energetic costs for some species yet to be a resource for others. This study tested the hypothesis that removal of benthic sediment through ingestion by Rana palmipes (Ranidae), a detritivorous tadpole, facilitated the growth of Ancistrus triradiatus (Loricariidae), an algivorous armored catfish. We hypothesized...

The influence of eutrophication of fluvial ecosystems (caused by increased phosphorus concentrations) on periphyton Cu sensitivity is explored from a multi-scale perspective, going from the field to the laboratory. The study design included three tiers: a field study including the characterization of land use and the ecological state of the corresponding river sections in the Fluvià River water...

The ingestion and digestion of two co-existing ephemeropteran larvae, Meridialaris diguillina (Leptophlebiidae) and Baetis sp (Baetidae) were examined and their mouthpart morphologies were compared. M. diguillina bears conspicuous brushinglike maxillae and Baetis sp has toothed, scope-like lacinia-galeae and mandibles. Larvae were fed on periphyton and faeces were collected for examination. The...

[1] Increasingly available high-resolution topographic data from remote sensing motivates the search for topographic features that predict abiotic controls on the distribution and performance of biota. We investigated the extent to which periphyton distribution and stream ecosystem metabolism in a steep upland river drainage network could be predicted from physical conditions that varied with l...

Longitudinal gradients in streamwater nutrient concentrations in Walker Branch are generated as a result of instream nutrient uptake and spatially confined groundwater inputs during the period from November to May. The response of the stream periphyton community to these longitudinal nutrient reductions was determined by measuring periphyton biomass, productivity, species composition, and phosp...

Mercury methylation and demethylation rates were measured in periphyton biofilms growing on submerged plants from a shallow fluvial lake located along the St. Lawrence River (Quebec, Canada). Incubations were performed in situ within macrophytes beds using low-level spikes of (199)HgO and Me(200)Hg stable isotopes as tracers. To determine which microbial guilds are playing a role in these proce...

The experiment was conducted in two cement made cisterns for a four-week period. Important physico-chemical water quality parameters and harvesting time in periphyton production were studied. During the study period, four groups of phytoplankton and two groups of zooplankton were observed. Among phytoplankton, Chlorophyceae was the most dominant having 62% Chlorella followed by Bacillariophycea...