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Showing 1 to 20 of 74 for “"Periphyton"”.
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Periphyton production in an Appalachian mountain trout stream
Temporal production patterns for periphyton have been poorly quantified in small woodland streams. In this study periphyton production on natural substrates was measured in a second order, western Virginia trout stream and two of its tributaries. Measurements were taken about three times monthly …
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Periphyton-nutrient dynamics in a gradient-dominated freshwater marsh ecosystem.
… from, the structure and function of the periphyton community were investigated. Field surveys, field experiments, and a laboratory experiments were conducted over a three year period in the Lake Waco Wetlands, a created wetland system near Waco, Texas. Results of these studies indicated …
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Nutrient Limitation of Upper Great Lakes Periphyton across Large Spatial and Environmental Gradients
Periphyton plays an important role in the food webs of large lakes, but their over-proliferation can be a major water quality concern in many systems. Managing periphyton blooms requires an understanding of what nutrients limit algal growth and how nutrient limitation interacts with other …
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Context-dependent controls of periphyton across the littoral-benthic habitat of deep, clear lakes
… radiation (PAR) measurements. We observed that periphyton nutrient limitation and inhibition vary with depth and habitat. Differences were primarily driven by the concentration of dissolved inorganic nitrogen (DIN) and the availability of PAR. Less DIN and more PAR favored N limitation and P …
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Interactions between titanium dioxide nanoparticle exposure and grazing organisms on periphyton biomass and community composition.
… dioxide nanoparticles (TiO₂NPs) were toxic to periphyton under environmentally realistic conditions and in the absence/presence of fish or snail grazing. In the riffle section of the streams, the high concentration treatment of TiO₂NPs (5 mg L⁻¹) significantly decreased periphyton biomass and …
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Assessing the use of periphyton as bioindicators of water quality, for use in Namibian inshore waters
Submitted in partial fulfilment for the degree of Master of Science (Environmental Science)
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The effects of nutrients and hydrology on periphyton and phytoplankton in Fraser River tributaries, British Columbia
… and taxonomic composition. July epilithic periphyton chlorophyll a was weakly correlated with TN, while October periphyton was significantly related to DP and conductivity. The phytoplankton biomass in July was best predicted by TP (r2 = 0.70, p ≤ 0.001, n = 19), while October …
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Characterization of the autotrophic component in periphyton upon <i>Typha angustifolia</i> detritus in a freshwater wetland
<p>The autotrophic component of periphyton on <em>Typha angustifolia</em> detritus was characterized in a freshwater wetland during a single growing season. 58 genera of algae and cyanobacteria, representing six divisions, were observed throughout the study period. Although the combined …
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The relationship between periphyton, flow and nutrients in foothill rivers of the south-western Cape, South Africa
… thesis examines spatial and temporal patterns in periphyton community composition and biomass and the environmental factors responsible for shaping these communities in south-western Cape rivers. The study focused on two prennial foothill rivers in the south-western Cape: the Berg River, which is …
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Heavy metal concentrations, primary productivity, chlorophyll-a levels, and the autotrophic indices of stream periphyton subjected to wood preservation waste
… June through September, 1981, in which the periphyton from ten locations in Culpeper, Virginia, were analyzed for arsenic, chromium, and copper, both upstream and downstream from the source of contamination. The periphyton primary productivity, chlorophyll-a content, and autotrophic index …
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A Method Comparison and Stressor-Response Experimental Study of Nitrogen and Phosphorus Impacts to Periphyton in Ozark Streams
… nutrient criteria. However, multiple methods of periphyton data collection are currently used, and little is known about the comparability of resulting datasets. Literature also suggests other factors besides nutrients (i.e. variable grazing, light, and flow) can confound algal-nutrient …
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Water Quality and the Primary Producers in the Upper James River, Missouri
Monthly water quality, periphyton biomass, and species composition were determined at three stations in the upper James River, Missouri, was determined from May to November 1980. Periphyton cell numbers (cells x 10⁵ cm⁻²) gradually increased during the study, and ranged from 3.43 to 32.9 x 10⁵ …
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Effects of copper on benthic communities in artificial microcosms
… investigated were colonization and growth of periphyton communities in artificial streams, community composition and nutritional content of periphyton in these streams, leaf conditioning and nutritional content in laboratory microcosms, and nutritional suitability of these leaves to a …
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Oxygen, pH, and labile organic carbon as possible mechanisms for algal stimulation of bacterial and fungal production in periphyton
<p>Algal photosynthesis can stimulate production of associated microbial heterotrophs; however,the mechanisms for this stimulation remain unknown. I incubated submerged Typha domingensis leaf litter in greenhouse mesocosms under low- and high-nutrient regimes and conducted microbial production …
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Effects of road salt on photosynthetic and enzyme activity of stream biofilms
… little information exists about its influence on periphyton. I measured extracelluar enzyme activity and photosynthetic activity of natural winter stream periphyton communities under various short-term laboratory salt exposures. The results of this study suggest that short-term exposure to …
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Effects of artificial light at night on benthic primary producers in freshwaters
… of benthic primary producers in freshwaters, the periphyton. The presented work is based on manipulative field studies performed in two contrasting freshwater systems whose periphyton communities are characterized by different species. The first study was performed in a stream-side flume system on …
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Water quality and biotic community response to an urban – rural land-use gradient in the Lake Simcoe watershed
… here explored the links between land-use, periphyton nutrient content and biomass, and invertebrate response in lotic surface waters in the LSW. To infer the contribution of cosmetic fertilizer use in the LSW, a community survey was conducted to assess lawn care and fertilizer choices by …
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The Role of Autochothnous Production in the Formation of Dissolved and Particulate Organics in Laboratory Streams
… light intensity, gross primary production, and periphyton standing crop decreased, the percentage of DOC produced increased. FPOC concentrations were approximately 1/3 to 1/9th DOC concentrations. The production of DOC and FPOC by the laboratory periphyton communities exposes the communities to …
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