Monocultures of functional equivalent species often negatively affect nutrient cycling and overall biodiversity of aquatic ecosystems. The importance of water and sediment nutrients for the occurrence of monocultures was analysed using field data from drainage ditches. Ranges of nutrients were identified that best explained the occurrence of monocultures of Elodea nuttallii (Planch.) St. John (...

Removal of dissolved organic carbon (DOC) from water resulting from adsorption and microbial uptake was examined to determine the importance of biotic and abiotic pathways. Physical-chemical adsorption to components of the stream sediment or water and biotic assimilation associated with the microbial population was determined in recirculating chambers utilizing leachate from alder (Alnus rubru)...

A riparian buffer (also known as riparian vegetative filter strips, or buffer strips) is an area of vegetated land surrounding a waterbody, potentially capable of filtering non-point source pollution in runoff from adjacent lands. Main pollutants studied include sediment, nitrogen, phosphorus, bacteria, and pesticides. Although the literature suggests a general consensus about a riparian buffer...

Although stimulation of dissimilatory metal reduction to promote the reductive precipitation of uranium has been shown to successfully remove uranium from some aquifer sediments, the organisms in the family Geobacteraceae that have been found to be associated with metal reduction in previous studies are not known to grow at the high salinities found in some uranium-contaminated groundwaters. St...

Dams are known to impact river channels and ecosystems, both during their lifetime and in their decommissioning. In this study, we applied a before-after-control-impact design associated with two small dam removals to investigate abiotic and biotic recovery trajectories from both the elimination of the press disturbance associated with the presence of dams and the introduction of a pulse distur...

Engineered flood bypasses, or simplified conveyance floodplains, are natural laboratories in which to observe floodplain development and therefore present an opportunity to assess delivery to and sedimentation within a specific class of floodplain. The effects of floods in the Sacramento River basin were investigated by analyzing hydrograph characteristics, estimating event-based sediment disch...

Changes to land use affect streams through nutrient enrichment, increased inputs of sediment and, where riparian vegetation has been removed, raised water temperature. We manipulated all three stressors in experimental streamside channels for 30 days and determined the individual and pair-wise combined effects on benthic invertebrate and algal communities and on leaf decay, a measure of ecosyst...

in this research the operation of fixed activated sludge system for treatment of wastewater containing heavy metal compounds, by use of fas pilot ,a plaxy glass tank with three section; these section are downward-flow aerated reactor, upward-flow aerated reactor and gravity sediment unit, length and width and height of each part was respectively 15.7cm, 31.5cm , 51.5 cm and feeding with the syn...

Abstract Observations and modeling are used to assess potential impacts of sediment releases due dam removals on the Hudson River estuary. Watershed loads calculated based sediment-discharge rating curves for gauges covering 80% watershed area. The annual average load estuary is 1.2 Mt, which about 0.6 Mt comes from side tributaries. Sediment yield varies inversely with area, regional trends th...