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Showing 1 to 13 of 13 for “"benthic algae"”.
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THE SEASONAL AND SPATIAL DISTRIBUTION OF THE MARINE BENTHIC ALGAE OF TUNISIA
<p>A detailed study of the marine flora of Tunisia was conducted by assessing the seasonal variation of seaweed populations along a 35 m transect at one site (La Marsa), as well as by qualitatively describing the species composition throughout the country, and comparing the floristic affinities of …
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Grazer control on benthic algae in the Berg River, Western Cape, South Africa
Benthic environments in streams are areas of high biological activity where primary producers and consumers interact with each other and the environment. Various factors such as light, nutrient availability and temperature affect algal biomass accumulation however disturbance factors and grazing …
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Concentrations of Selected Metals in Benthic Algae From the Headwaters Region of Crane Creek, Stone County, Missouri
Samples of benthic algae from two tributaries at the headquarters of Crane Creek in northwest Stone County, Missouri were collected and tested for the presence and concentration of chromium, copper, lead, nickel, and zinc by flame atomic absorption spectrophotometry. Mean metal levels in algae from …
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Ecological and Trophic Distribution of Pesticides in Lack Poinsett, South Dakota
… were water, bottom sediment, zooplankton, benthic algae, crayfish, aquatic insects and fish. Concentrations of aldrin, DDD, DDE, DDT, dieldrin, endrin, heptachlor, heptachlor epoxide, lindane, methoxychlor, and toxaphene were determined by gas chromatography and thin-layer chromatography. …
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Impacts of non-native rainbow trout on stream food webs in the Cape Floristic Region, South Africa integrating evidence from surveys and experiments
… Region, South Africa. Fish populations, benthic invertebrate assemblages, benthic algae and particulate organic matter were surveyed in each of 24 minimally-disturbed headwater streams in the upper Breede River catchment, and relevant environmental variables in each stream measured, over …
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Ecological characteristics of stream reaches with and without low-tech process-based restoration in a wildfire-affected watershed
… differences in sediment size, water temperature, benthic algae, fine and particulate organic matter, large wood, riparian vegetation, macroinvertebrate communities, and brook trout density and size structure. The relict beaver site had more shallow, lentic habitat, finer substrate, increased …
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Effect of Macrograzers (Campostoma spp. and Faxonius spp.) on Periphyton in Ozark Streams with Considerations Given to Macrograzer Biomass, Phosphorus, and Season: Mensurative and Manipulative Studies
<p>Nutrient and benthic algal biomass relationships can guide numeric nutrient criteria development in lotic systems. However, herbivorous macrograzers may confound this relationship by reducing the slope of the positive relationship between nutrients and periphyton biomass in streams. I conducted …
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Trace metals in upper Susquehanna River ecosystem: environmental distribution, urban impacts, and interaction with sediment materials
… municipal wastewaters and sewage sludge, algae and fish] were collected and analyzed for the following Trace Metals (TMs), as appropriate: Pb, Cd, Co, Ni, Cr, Cu, Zn, and total and inorganic Hg. The median and range of TMs found in RW samples help establish baseline values for the …
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Ecology of chemical defenses of algae against the herbivorous snail, Littorina littorea, in the New England rocky intertidal community
… by two perennial plant types, brown fucoid algae (Ascophyllum nodosum and several species of Fucus) in the mid zones and the red alga Chondrus crispus in the low zones. These algae are not grazed by the predominant herbivorous snail, Littorina littorea. Here I report the first direct …
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Lake Benthic Algal Production and Extracellular Material
… its importance to the lake as a whole. Benthic extracellular material, shown to be important for food web dynamics and stabilization of the surrounding ecosystem in the marine intertidal, is even less frequently studied in lakes. I examined the environmental and community level drivers …
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Food webs in the lower Waikato River and the role of hydrogeomorphic complexity
… autochthonous carbon, especially in the form of benthic algae and phytoplankton, to food webs in a variety of large rivers along with a range of secondary carbon sources that can assume importance depending on temporal and spatial variation in hydrogeomorphic conditions. The geographic spread of …
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Organic Matter Processes of Constructed Streams and Associated Riparian Areas in the Coalfields of Southwest Virginia
… oxidized nitrogen concentrations, depressed benthic macroinvertebrate richness, and lower levels of canopy cover. Functionally, litterfall input and total leaf breakdown means for constructed streams were approximately 25% and 60% of reference means, respectively. Leaf breakdown in …