Outfall Of Power Plant Research Articles

Zooplankton community size-structure change and mesh size selection under the thermal stress caused by a power plant in a semi-enclosed bay

Zooplankton samples were collected using 505, 160 and 77 µm mesh nets around a power plant during four seasons in 2011. We measured total length of zooplankton and divided zooplankton into seven size classes in order to explore how zooplankton community size-structure might be altered by thermal discharge from power plant. The total length of zooplankton varied from 93.7 to 40 074.7 µm. The spatial distribution of mesozooplankton (200 −2 000 µm) populations were rarely affected by thermal discharge, while macro- (2 000 −10 000 µm) and megalo-zooplankton (>10 000 µm) had an obvious tendency to migrate away from the outfall of power plant. Thus, zooplankton community tended to become smaller and biodiversity reduced close to power plant. Moreover, we compared the zooplankton communities in three different mesh size nets. Species richness, abundance, evenness index and Shannon-Wiener diversity index of the 505 µm mesh size were significantly lower than those recorded from the 160 and 77 µm mesh size. Average zooplankton abundance was highest in the 77 µm mesh net ((27 690.0±1 633.7) ind./m3), followed by 160 µm mesh net ((9 531.1±1 079.5) ind./m3), and lowest in 505 µm mesh net ((494.4±104.7) ind./m3). The ANOSIM and SIMPER tests confirmed that these differences were mainly due to small zooplankton and early developmental stages of zooplankton. It is the first time to use the 77 µm mesh net to sample zooplankton in such an environment. The 77 µm mesh net had the overwhelming abundance of the copepod genus Oithona, as an order of magnitude greater than recorded for 160 µm mesh net and 100% loss through the 505 µm mesh net. These results indicate that the use of a small or even multiple sampling net is necessary to accurately quantify entire zooplankton community around coastal power plant.

Size, growth, and density data for shallow-water sea urchins from Mexico to the Aleutian Islands, Alaska, 1956-2016.

Size, growth, and density have been studied for North American Pacific coast sea urchins Strongylocentrotus purpuratus, S.droebachiensis, S.polyacanthus, Mesocentrotus (Strongylocentrotus) franciscanus, Lytechinus pictus, Centrostephanus coronatus, and Arbacia stellata by various workers at diverse sites and for varying lengths of time from 1956 to present. Numerous peer-reviewed publications have used some of these data but some data have appeared only in graduate theses or the gray literature. There also are data that have never appeared outside original data sheets. Motivation for studies has included fisheries management and environmental monitoring of sewer and power plant outfalls as well as changes associated with disease epidemics. Studies also have focused on kelp restoration, community effects of sea otters, basic sea urchin biology, and monitoring. The data sets presented here are a historical record of size, density, and growth for a common group of marine invertebrates in intertidal and nearshore environments that can be used to test hypotheses concerning future changes associated with fisheries practices, shifts of predator distributions, climate and ecosystem changes, and ocean acidification along the Pacific Coast of North America and islands of the north Pacific. No copyright restrictions apply. Please credit this paper when using the data.

The Hydraulic and Environment Effect of El-Ain-Al Sokhna Power Plant

The demand on electrical power in Egypt increase to supply industrial and public utility needs. In this manner new power plants are being constructed at different spots in Egypt in order to meet that demand. El-Ain-Al Sokhna super critical steam turbine (2*650 MW) has been operated in 2012. It is located 52Km south Suez city The Power Plant uses a direct once through cooling system using water taken from the Suez Gulf and discharged with higher temperature . The discharge of processed water which has higher temperature affects both physical and chemical properties of water. It changes its density, vapour pressure, viscosity, surface tension, gas solubility, diffusion, and chemical reactions which have influence on the local physical, chemical and ecological of marine environment. This paper studies the hydraulic and environment impact of the El-Ain-Al Sokhna power plant on the surrounding area under different wind conditions and tidal forces using numerical modeling. A hydrodynamic model for the study area has been developed using Delft3D. Data for site description, water levels, velocity measurements, wind data and water quality have been collected and used in model setup and calibration. Different scenarios have been simulated under different tidal and wind conditions .The effect of changing the intake location and the feasibility of adding a breakwater to minimize the entrance of thermal plume from the El-Ain-Al Sokhna power plant and Suez Gulf power plant outfalls have been studied .The temperature distribution results have been compared with the environmental regulations Dimension analysis of the factors affecting the temperature distribution and an equation for the intake temperature have been developed.

Winter Habitat Preferences for Florida Manatees and Vulnerability to Cold

To survive cold winter periods most, if not all, Florida manatees rely on warm-water refuges in the southern two-thirds of the Florida peninsula. Most refuges are either warm-water discharges from power plant and natural springs, or passive thermal basins that temporarily trap relatively warm water for a week or more. Strong fidelity to one or more refuges has created four relatively discrete Florida manatee subpopulations. Using statewide winter counts of manatees from 1999 to 2011, we provide the first attempt to quantify the proportion of animals using the three principal refuge types (power plants, springs, and passive thermal basins) statewide and for each subpopulation. Statewide across all years, 48.5% of all manatees were counted at power plant outfalls, 17.5% at natural springs, and 34.9 % at passive thermal basins or sites with no known warm-water features. Atlantic Coast and Southwest Florida subpopulations comprised 82.2% of all manatees counted (45.6% and 36.6%, respectively) with each subpopulation relying principally on power plants (66.6% and 47.4%, respectively). The upper St. Johns River and Northwest Florida subpopulations comprised 17.8% of all manatees counted with almost all animals relying entirely on springs (99.2% and 88.6% of those subpopulations, respectively). A record high count of 5,076 manatees in January 2010 revealed minimum sizes for the four subpopulations of: 230 manatees in the upper St. Johns River; 2,548 on the Atlantic Coast; 645 in Northwest Florida; and 1,774 in Southwest Florida. Based on a comparison of carcass recovery locations for 713 manatees killed by cold stress between 1999 and 2011 and the distribution of known refuges, it appears that springs offer manatees the best protection against cold stress. Long-term survival of Florida manatees will require improved efforts to enhance and protect manatee access to and use of warm-water springs as power plant outfalls are shut down.

Use of Human‐Altered Habitats by Bull Sharks in a Florida Nursery Area

AbstractBull Sharks Carcharhinus leucas in the Indian River Lagoon, Florida, have been documented to frequently occur in human‐altered habitats, including dredged creeks and channels, boat marinas, and power plant outfalls. The purpose of this study was to examine the short‐term movements of age‐0 and juvenile Bull Sharks to quantify the extent to which those movements occur in altered habitats. A total of 16 short‐term active acoustic tracks (2–26 h) were carried out with 9 individuals, and a 10th individual was fitted with a long‐term coded transmitter for passive monitoring by fixed listening stations. Movement and activity space statistics indicated high levels of area reuse over the span of tracking (hours to days). All but one shark usedaltered habitat at some point during tracking, such that 51% of all tracking positions occurred in some type of altered habitat. Of the sharks that used altered habitat, the mean (±1 SD) percent of positions within altered habitat was 66 (±40)%. Furthermore, tracks for 3 individuals indicated selection for altered habitats. The single passively monitored Bull Shark was detected in power plant outfalls almost daily over a 5‐month period, providing the first indication of longer‐term fidelity to thermal effluents. Use of one dredged creek was influenced by local salinity, the tracked sharks dispersing from the altered habitat when salinity declined. The affinity of young Bull Sharks to altered habitats in this system could help explain their reported accumulation of a variety of harmful contaminants, which could negatively affect their health and survival.Received July 27, 2012; accepted November 28, 2012

Tidal Cycle Effects on the Occurrence of the Florida Manatee (Trichechus manatus latirostris) at the Port Everglades Power Plant

The seasonal distribution of the Florida manatee (Trichechus manatus latirostris) is influenced predominantly by feeding locations in the summer and proximity to warm-water refuges during colder months. Due to their limited ability to tolerate cold water, when water temperatures drop below 20°C manatees congregate around natural and artificial warm-water refuges, such as warm-water springs or power plant outfalls. Distribution may further be influenced by the tidal cycle through its impact on manatee movement and foraging. Although the importance of tide on manatee distribution and habitat selection has been acknowledged, it has yet to be studied quantitatively in respect to the manatee population in southeast Florida. The purpose of this study was to examine the effect of the tidal cycle on manatee occurrence at the Florida Power & Light (FPL) Port Everglades Power Plant. Walking surveys were conducted in Port Everglades during manatee season, November 15 – March 31, between 2004 and 2008. During the surveys, the number of manatees in four established locations was noted and the animals categorized based on size as either calf, juvenile, or adult. Water temperature data were also collected at four permanent sample locations. Because many surveys yielded zero manatees observed, data were analyzed using the zero-inflated negative binomial model. Although the manatees at the Port Everglades Power Plant must forage away from the warm-water refuge, my findings show no correlation between tidal state and total manatee occurrence at the FPL Port Everglades Power Plant. The results do, however, suggest that the probability of observing a cow/calf pair is greater during high tide when compared to low and mid-tides (P < 0.05). Total manatee occurrence and the presence of cow/calf pairs were both significantly correlated with water temperature (P < 0.05).

Seasonal Distribution and Habitat Associations of Bull Sharks in the Indian River Lagoon, Florida: A 30‐Year Synthesis

AbstractMany coastal shark species use shallow estuarine regions as nursery habitat, but there are considerable gaps in our understanding of the seasonal distribution and habitat use patterns of sharks within these systems. We compiled all available sampling data from the Indian River Lagoon (IRL) along Florida's central Atlantic coast to examine the distribution of bull sharks Carcharhinus leucas. The data synthesized in this study spanned the 30‐year period 1975–2005 and included information on the seasonal distribution, size structure, and habitat associations of 449 bull sharks. For comparison, data from an additional 106 bull sharks captured in shelf waters adjacent to the IRL were also examined. The IRL is dominated by young‐of‐the‐year (age‐0) and juvenile bull sharks, which were most abundant during spring, summer, and autumn. Shark captures were most often associated with shallow freshwater creeks, power plant outfalls, ocean inlets, and seagrass habitats with temperatures greater than 20°C, salinities of 10–30‰, and dissolved oxygen concentrations between 4 and 7 mg/L. Juvenile bull sharks were found in waters with higher mean salinities than were age‐0 sharks. Although the IRL is one of the most important bull shark nursery areas on the U.S. Atlantic coast, catch‐per‐unit‐effort data indicate that bull shark abundance decreases with increasing latitude within and north of the IRL, suggesting that the IRL is the northern limit of functional nursery habitat for this species in the northwest Atlantic Ocean.

Application of cellulolytic activity of asiatic clams (Corbicula SP.) to in‐stream monitoring of power plant effluents

AbstractRigorous testing schemes in field‐located artificial streams and in‐stream monitoring provided evidence for use of Corbicula cellulolytic activity as a highly sensitive and efficient approach to effluent assessment. Cellulolytic (exo‐ and endocellulase) activity of the Asiatic clam, Corbicula sp., determined in 30‐d, field‐located artificial stream exposures at the New River, Virginia to single components of power plant effluents (copper [Cu] and zinc [Zn] separately) was compared with cellulolytic responses in caged clams from within an impacted area of the Clinch River, Virginia below power plant effluents. Cellulolytic responses were then compared to conventional biomonitoring responses (Hester‐Dendy macroinvertebrate community structure), water quality monitoring in the Clinch River, and laboratory artificial stream bioassays. Clam enzyme activity was significantly reduced in 10 to 20 d (α = 0.05) at 16 and 87 μg Cu and Zn/L, respectively, in field‐located artificial streams. Cellulolytic activity of clams caged at stations within power plant outfalls (metal concentrations of 47–78 μg Zn/L and 80–345 μg Cu/L) was significantly reduced to levels as low as 9 to 52% of upstream activity levels. Reduction in cellulolytic activity in Corbicula was more sensitive after 14 d of in‐stream monitoring than reduction in diversity of macroinvertebrate assemblages after 28 d. Bioassay exposures as long as 30 d were needed to provide toxicity data comparable to enzyme impairment seen as early as 10 d.