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Showing 1 to 20 of 97 for “"mesocosms"”.
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Ecotoxicological Investigations in Effluent-Dominated Stream Mesocosms
… on effluent-dominated stream ecosystems. Stream mesocosms, fed municipal effluent from the City of Denton, TX, Pecan Creek Water Reclamation Plant (PCWRP), were treated with 0, 15 or 140 µg/L cadmium for a 10-day study in August 2000. Laboratory toxicity test and stream macroinvertebrate …
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Treatment performance assessments of different wetland mesocosms
Despite their global acceptance as a sustainable and cost-efficient technology for water pollution control including urban wastewater contaminated with hydrocarbons, treatment performance of vertical-flow constructed wetlands can be hampered by clogging of the substrate media pores of the wetland …
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Alkyl Polyglucoside Compound Influences Freshwater Plankton Community Structure in Floating Mesocosms
… to zooplankton and water quality. Floating mesocosms (440 L) were deployed in a blackwater pond in southeast Georgia, USA and dosed with 0, 0.01, 2.5, 5, or 10 mg L<sup>-1</sup> APG. Zooplankton community composition, phytoplankton abundance (as chlorophyll-a), and dissolved oxygen (DO) were …
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From single species to mesocosms: responses of freshwater copepods and their community to PCP
… derived laboratory microcosms and in situ mesocosms dosed with pentachlorophenol (PCP). Acute 48 h lethality tests used two copepod life stages (nauplii and adults). Tests were conducted at 22°C with laboratory cultured animals of all species and at varying temperatures with seasonally …
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Phytoremediation of Weathered Petroleum in Groundwater by Arroyo Willows in Nutrient Amended On-Site Mesocosms
… BY ARROYO WILLOWS IN NUTRIENT AMENDED ON-SITE MESOCOSMS SARAH BRAGG-FLAVAN A large-scale mesocosm study was conducted to determine if vegetation with willow trees enhances biodegradation and to evaluate the mechanisms of natural biodegradation of weathered petroleum compounds under field …
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Using Mesocosms to Model Optimal Levels of Body Size Variation in Larval Spotted Salamanders (Ambystoma maculatum)
… exhibited 38% lower survival than low density mesocosms, and metamorphs from high density populations were 11% smaller. Population size structures experienced shifts throughout the larval period, generally becoming less variable, though populations with higher initial levels of size variation …
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Phytoplankton community structure response to groundwater-borne nutrients in the Inland Bays, DE
… and NH4 + up to 55 µmol/L. As a result treatment mesocosms had NO 3- concentrations up to 55.5 µmol/L and NH 4+ up to 4.0 µmol/L, while control mesocosms received filtered seawater, and were thus relatively low in nutrients (24.2 µmol/L NO3- and ∼2 µmol/L NH4 +). In June the highest chlorophyll a …
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Ecosystem Functional Consequences of Top Predator Mortality Due to the Invasive Shrub, Lonicera maackii
… and availability of soluble nutrients. Of the 20 mesocosms that contained larval A. maculatum, only 11 produced metamorphs, and only one mesocosm with leaf litter from L. maackii produced metamorphs. All 10 mesocosms containing A. maculatum larvae and native leaf litter produced metamorphs. A …
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Evaluation of Digital PCR (dPCR) for the Quantification of Soil Nitrogen Turnover Bacteria in Wetland Mesocosms in Response to Season, Fertilization, and Plant Species Richness
Excess nutrients from nonpoint sources are an ongoing problem that is expected to worsen as population and fertilizer usage rise. Conventional centralized treatment systems are not well suited to address nonpoint source pollution. More distributed best management practices (BMPs) like constructed …
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Effects of Phorate on Ducklings, Macroinvertebrates, and Microtox in Northern Prairie Wetlands
… macroinvertebrates was studied in littoral mesocosms in South Dakota wetlands. In 1991 and 1992, four mesocosms were constructed in each of three wetlands. In each wetland, one mesocosm was a reference and phorate concentrations of 1.2, 2.4, and 4.8 kg/ha were applied to treatment mesocosms. …
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A problem driven approach to the miniaturizsation and automation of enzyme-based assays and an investigation of the dissipation of cyanazine and bromide in wetland mesocosms
… analysis of pond water drawn from wetland mesocosms treated with a herbicide and a volume tracer. The significance of this work is two-fold. First, inherent in a field study of this scope is the analytical challenges associated with sampling, sample handling and analysis specifically with …
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Influence of vegetation on sediment bacterial community structure, microbial enzyme activities and phosphorus retention in constructed freshwater wetlands
… was conducted using unvegetated or vegetated mesocosms with Juncus effusus, Carex lurida or Dichanthelium acuminatum var. acuminatum in monoculture or mixed culture. </p> <p>To study the influence of vegetation on the bacterial community structure and microbial enzyme activities, sediment …
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The effect of carbon addition, pH and Fe concentration of microbial sulfate reduction and the subsequent precipitation of Fe and Mn from acid mine drainage in wetland mesocosms
… precipitation of Fe and Mn was determined in mesocosms built to simulate a wetland. Mesocosms were constructed with plexiglass sheets and measured 6" x 6" x 24". Each mesocosm was filled with a 4-inch layer of limestone gravel beneath 17 inches of weathered pine bark mulch. A perforated PVC …
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Water Column Productivity, Calcite Precipitation, and Phosphorus Dynamics in Freshwater Marshes
… marshes and in twenty 1-m2 experimental mesocosms in central Ohio. Water, algae, and sediment samples were taken from July 1998 to May 1999 at sitesfrom the inflow to the outflow of the marshes. Diurnal dissolved oxygen data taken every half-hour from July 1996 through December 1998 at …
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Tree functional diversity affects litter decomposition and arthropod community composition in a tropical forest
… and different litter mixtures in experimental mesocosms in a 60-year-old secondary forest to assess changes in soil respiration and decomposition rates within a single experimental arena. Litter mixtures represented different combinations of tree functional groups. Arthropods >2.5 mm were …
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Phytoremediation of nitroglycerin in smokeless powders
… Double base smokeless powder was applied to soil mesocosms at rates of 0, 1.0, 5.0 and 10% (w/w). Nitroglycerin-contaminated mesocosms were seeded with oats (Avena sativa) or planted with live sedge plants (Carex vulpinoidea). In addition, composted biosolids were used as a soil treatment. …
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OCEAN ACIDIFICATION: UNDERSTANDING THE COASTAL CARBON PUMP IN A HIGH CO2 WORLD
… or bacterial communities in large, stationary mesocosms. Few studies have coupled both phytoplankton and bacterial processes and even fewer have investigated coastal communities, where pH and pCO2 can vary drastically. This study focused first on developing and evaluating a mesocosm and …
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Macroinvertebrate colonization and production in new experimental ponds
… was typical of shallow lentic environments, the mesocosms were not considered ready for use in chemical testing because of low densities of other macroinvertebrates. The mesocosms were somewhat variable in regard to community structure, however, no mesocosm was found to be a consistent outlier. …
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Indirect genetic effects of rhizobium symbiosis plasmid on legume-grass dynamics
… dynamics, we inoculated experimental mesocosms of mixed clover and grass with one of four treatments: rhizobia with high-quality pSym clade A, rhizobia with low-quality pSym clade C, rhizobia lacking the pSym, or no rhizobia (mock inoculation). We demonstrate that variation in the …
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