The Everglades Nutrient Removal Project test cells: STA optimization - status of the research at the north site

2001 ◽  
Vol 44 (11-12) ◽  
pp. 117-122 ◽  
Author(s):  
J. Majer Newman ◽  
T. Lynch
Keyword(s):  
Nutrient Removal ◽  
Organic Phosphorus ◽  
Inorganic Compounds ◽  
Monitoring Program ◽  
South Florida ◽  
Particulate Phosphorus ◽  
Phosphorus Concentration ◽  
The North ◽  
Test Cells ◽  
Oligotrophic Ecosystem

The Everglades is an oligotrophic ecosystem that is being adversely impacted by hydrologic changes and nutrient-rich runoff generated from urban and agricultural sources. The Stormwater Treatment Area (STA) Optimization Research and Monitoring program is mandated by the 1994 Everglades Forever Act and will assist the South Florida Water Management District in developing operational strategies that maximize performance of emergent macrophyte STAs. The primary objective of this research is to examine how hydrologic conditions may influence STA performance. The study was conducted in 0.2 ha, shallow, fully lined test cells located within the perimeter of the Everglades Nutrient Removal Project. Experiments were designed to examine the effect of increased and decreased hydraulic loading rate (HLR) on wetland performance and to determine, if possible, the HLR at which STA treatment fails to reduce outflow total phosphorus concentration to the interim target of 50 μg-P/L. To date, two HLR experiments have been completed at the north site. Preliminary data indicated at all HLRs tested that particulate phosphorus and dissolved organic phosphorus ratios remained virtually unchanged from inflow to outflow. The dissolved organic and particulate compounds within these test cells are extremely recalcitrant, and are not easily assimilated within the system. High HLRs may not result in detention times long enough to mineralize these forms into easily assimilated inorganic compounds, resulting in mean TP concentrations greater than 50 μg-P/L.

Characterisation of phosphorus in sediments from waste stabilization ponds

2000 ◽  
Vol 42 (10-11) ◽  
pp. 257-264 ◽  
Author(s):  
E. Gómez ◽  
J. Paing ◽  
C. Casellas ◽  
B. Picot
Keyword(s):  
Organic Phosphorus ◽  
Inorganic Phosphorus ◽  
Phosphorus Release ◽  
High Rate ◽  
Sediment Surface ◽  
Particulate Phosphorus ◽  
Phosphorus Concentration ◽  
Iron Hydroxides ◽  
Stabilization Ponds ◽  
Waste Stabilization

The waste stabilization pond (WSP) systems are useful for the treatment of wastewater. Despite a good knowledge of these systems, the dynamics of phosphorus elimination in these systems are not well known, especially concerning the forms of phosphorus in the sediment. Phosphorus dynamics were studied with data collected from the three stabilization ponds of the Mèze (France) system. A conceptual model based on theoretical considerations was developed, and applied to each pond. The percentage of observed variation described by these models ranged between 46.2% and 74.1%. The results showed that the principal variables affecting orthophosphate in WSP systems were phosphorus input and particulate phosphorus. When the model was applied to high rate algal pond (HRAP) data, the role of photosynthesis on pH increase and P precipitation was clear. Sediments sampled in the three facultative ponds were characterised with a fractionation scheme, currently used for sediments of natural aquatic ecosystems. Inorganic phosphorus accounted for 92-94% of total sediment phosphorus, with 57–59% bound to iron hydroxides and 33–37% bound to calcium. Surprisingly, organic phosphorus represented only between 6 and 8%. Polyphosphate was detected. Phosphorus concentration was greatest in the sediment from the third pond, where an aerobic layer at the sediment surface prevented phosphorus release.

scholarly journals Phosphorus dynamics in the water of tropical semiarid reservoirs in a prolonged drought period

2018 ◽  
Vol 30 (0) ◽  
Author(s):  
Herika Cavalcante ◽  
Fabiana Araújo ◽  
Vanessa Becker
Keyword(s):  
Water Column ◽  
Organic Phosphorus ◽  
Soluble Reactive Phosphorus ◽  
Particulate Phosphorus ◽  
Semiarid Region ◽  
Drought Period ◽  
Chl A ◽  
Dissolved Phosphorus ◽  
Phosphorus Dynamics ◽  
Prolonged Drought

Abstract Aim To verify the vertical distribution of phosphorus in the water and to identify the predominant forms of P in the water column for understand the phosphorus dynamics in tropical semiarid reservoirs during a prolonged drought period. Methods Two reservoirs from the semiarid region of Rio Grande do Norte were analysed during the period from May 2015 to June 2016. Were analysed: Suspended solids (SS), chlorophyll a (Chl-a), dissolved oxygen (OD) and temperature. Vertical profiles were plotted for total phosphorus (PT), total dissolved phosphorus (PTD), particulate phosphorus (PP), dissolved organic phosphorus (POD) and soluble reactive phosphorus (FRS). Results The phosphorus values distributed in the water column were high for both reservoirs, presenting the highest values during the periods with lower depth. Gargalheiras presented greater predominance of PT and PP, while Cruzeta had the highest values of FRS. Chl-a and SS values were also consistent with phosphorus values: Chl-a was higher in Gargalheiras, while SS, mainly inorganic, were higher in Cruzeta. Gargalheiras presented anoxic conditions close to the sediment from May 2015 to December 2015, which may induce the release of phosphorus from the sediment to the water column. Values that are too high during the shallower months, especially in Cruzeta, may have been influenced by the release of P from sediment through wind resuspension. Conclusions The amounts and predominant types of phosphorus in the water column are of great importance to understand the phosphorus dynamics and will support restoration plans for the studied environments. In this study it was possible to verify that the reservoirs are susceptible to the release of P from the sediment due to the environmental conditions, mainly low depths, resuspension of the wind and anoxia in the hypolimnion.

scholarly journals Effects of waves and currents on the siltation problem of Damietta harbour, Nile Delta coast, Egypt

2007 ◽  
Vol 8 (2) ◽  
pp. 33 ◽  
Author(s):  
ABO BAKER.I. ABO ZED
Keyword(s):  
Sediment Transport ◽  
Nile Delta ◽  
Monitoring Program ◽  
Wave Direction ◽  
Littoral Drift ◽  
Wave Refraction ◽  
The North ◽  
Dynamic Factors ◽  
Navigation Channel ◽  
Nile Delta Coast

This study evaluates the effect of prevailing dynamic factors on the sedimentation process in Damietta Harbour along the Nile delta coast of Egypt. The monitoring program spanned the period between 1978 and 1999 and included measurements of waves, currents and bathymetric profiles. The evaluation was based on determination of erosion and accretion rates, current regime, sediment transport, wave characteristics and wave refraction. Results revealed that the predominant wave direction from N-NW sector (86 %) throughout the year is responsible for generation of a longshore eastward current. Less frequent waves from the N-NE sector generate an opposing longshore westward current. The refraction pattern for the prevailing wave direction indicates that the harbour and its navigation channel are located within a divergence of wave orthogonal and in an accretion sediment sink area. The annual net rate of littoral drift on the western side of the harbour is about 1.43 * 105 m3 (accretion), while the annual net rate of littoral drift on the eastern side is about 2.54 * 105 m3 (erosion). Currents fluctuate tremendously in speed and direction, especially during the winter months. Hence, sediment transport takes place in offshore, eastward, and onshore directions. Progressive vector diagrams show that the largest near bottom offshore, onshore and easterly net drift occurs during summer, spring and winter respectively. The onshore sediment transport generated during spring and summer plays an important role in the redistribution of eroded sediments during the winter. The overall study of dynamic factors indicated that the harbour site is characterized by eastern, western, offshore and onshore sediment movements. Therefore, the north-south orientation of the navigation channel, with its depth greater than the surrounding area, interrupts sediment drift from different directions and reduces the current speed. Consequently, the sediments sink within the navigation channel from different directions. The sources of sediments contributing to the siltation process of the harbour and its navigation channels are mainly derived from the Rosetta promontory, Burullus beaches, Damietta promontory and from offshore and the dumping area.

Comparison of phosphorus removal characteristics between various biological nutrient removal processes

1997 ◽  
Vol 36 (12) ◽  
pp. 61-68 ◽  
Author(s):  
Eun Lee Sang ◽  
Soo Kim Kwang ◽  
Hwan Ahn Jae ◽  
Whoe Kim Chang
Keyword(s):  
Adverse Effect ◽  
Nutrient Removal ◽  
Phosphorus Removal ◽  
Phosphorus Release ◽  
Biological Nutrient Removal ◽  
Phosphorus Concentration ◽  
Bench Scale ◽  
Removal Processes

Bench scale experiments were carried out with four biological nutrient removal(BNR) units, A/O, A2/O, Phostrip and P/L units, to investigate the behavior of phosphorus in the system and to compare the characteristics of phosphorus removal in four experimental BNR units. The influent COD/T-P ratio was varied from 22 to 64 by changing COD concentration while maintaining phosphorus concentration constant. In general sidestream BNR units such as Phostrip and P/L units outperformed mainstream BNR units such as A/O and A2/O units in terms of phosphorus removal. While phosphorus release and uptake in A/O and A2/O units became less significant at low influent COD/T-P, the phosphorus release in A2/O unit was further influenced by nitrate in return sludge and thus A2/O unit required even higher influent COD/T-P ratio for luxury uptake of phosphorus. The luxury uptake of phosphorus in Phostrip and P/L units were not affected by influent COD/T-P ratio and the adverse effect of nitrate in return sludge on anaerobic phosphorus release in P/L process was not significant due to the sludge blanket in P-stripper.

scholarly journals Spatial and Seasonal Distribution and Transportation of Different Forms of Phosphorus in the Middle Reaches of the Yarlung Zangbo River

Water ◽  
2018 ◽  
Vol 10 (12) ◽  
pp. 1858 ◽  
Author(s):  
Xiaolong Cheng ◽  
Yanan Huang ◽  
Xunchi Pu ◽  
Ruidong An ◽  
Wendian Huang ◽  
...  
Keyword(s):  
Surface Sediments ◽  
Organic Phosphorus ◽  
Nutrient Status ◽  
Inorganic Phosphorus ◽  
Research Area ◽  
Phosphorus Concentration ◽  
Wet Season ◽  
Overlying Water ◽  
Total Phosphorus Concentration ◽  
Yarlung Zangbo River

The Yarlung Zangbo River basin ecosystem is fragile. The distribution and transportation of phosphorus is of great significance for aquatic environmental protection and ecological security. The sequential extraction method and molybdenum antimony anti-spectrophotometry were used to measure the concentrations of different forms of phosphorus in the surface sediments from 15 sampling sites along the middle reaches of the Yarlung Zangbo River and its tributaries. The results show that the total phosphorus concentration in the surface sediments is 194.0~540.7 mg/kg, which is mainly composed of inorganic phosphorus. The concentrations of various phosphorus forms ranked as calcium-bound phosphorus (355.6 ± 86.0 mg/kg) > soluble phosphorus (15.9 ± 10.0 mg/kg) > iron-bound phosphorus (12.4 ± 12.3 mg/kg) > organic phosphorus (9.6 ± 6.1 mg/kg) > occluded phosphorus (9.2 ± 3.8 mg/kg) > aluminum-bound phosphorus (5.4 ± 2.3 mg/kg). On the whole, phosphorus concentration is greater in wet season than dry season. Regarding the spatial distribution characteristics, there are great disparities in the different forms of phosphorus in the middle reaches of the Yarlung Zangbo River. Comprehensive analysis shows that phosphorus of this area is mainly self-generated, and concentration of bioavailable phosphorus is small, demonstrating there will not be a large release. We also drew a “specific triangle” of the different forms of phosphorus concentrations in the research area and defined the “α” angle to determine the nutrient status of the overlying water quickly and effectively. Finally, phosphorus flux of the mainstream was estimated. This research may provide information on the phosphorus of Plateau Rivers.

Evaluation of phosphorus retention in a South Florida treatment wetland

2001 ◽  
Vol 44 (11-12) ◽  
pp. 109-115 ◽  
Author(s):  
M.K. Nungesser ◽  
M.J. Chimney
Keyword(s):  
Removal Efficiency ◽  
Nutrient Removal ◽  
Aquatic Vegetation ◽  
South Florida ◽  
Superior Performance ◽  
Stormwater Treatment ◽  
Treatment Wetland ◽  
Operational Conditions ◽  
Macrophyte Community ◽  
Floating Macrophyte

The Everglades Construction Project of the South Florida Water Management District (District) will employ large constructed wetlands known as Stormwater Treatment Areas (STAs) to reduce phosphorus concentrations in runoff entering the Everglades. The District built and operated a prototype STA, the 1,545 ha Everglades Nutrient Removal Project (ENRP), to determine the efficacy of subtropical wetlands for improving regional water quality with a focus on reducing total phosphorus (TP). In five years of operation, the ENRP has consistently exceeded its performance goals of TP outflow concentrations <50 μg P/L and a 75% TP load reduction. Since August 1994, the ENRP has retained 70.3 metric tons of TP that otherwise would have entered the Everglades. When corrected for surface area and inflow TP load, TP removal efficiency was highest in the inflow buffer cell and decreased generally in a downstream fashion through the wetland. High TP removal efficiency in treatment cell 4 was attributed to superior performance of its submerged aquatic vegetation community relative to the emergent and floating macrophyte community in the other cells. Controlled experiments in the District's STA Optimization Research Program will help clarify what effect vegetation and operational conditions may have on nutrient removal in the STAs.

scholarly journals Estimating efficiency of survey and commercial trawl gears from comparisons of catch-ratios

2017 ◽  
Vol 74 (5) ◽  
pp. 1448-1457 ◽  
Author(s):  
Nicola D. Walker ◽  
David L. Maxwell ◽  
Will J. F. Le Quesne ◽  
Simon Jennings
Keyword(s):  
Monitoring Program ◽  
Data File ◽  
Species Group ◽  
Additive Models ◽  
Reference Points ◽  
Target Species ◽  
Commercial Catch ◽  
The North ◽  
Gear Efficiency ◽  
Species Groups

Abstract Assumptions about gear efficiency and catchability influence estimates of abundance, mortality, reference points and catch potential. Despite the need to better quantify fishing effects on some target species and on many non-target species taken as bycatch, there are few gear efficiency estimates for some of the most widely deployed towed fishing gears in the northeast Atlantic. Here, we develop a method that applies generalised additive models to catch-at-length data from trawl surveys and a commercial catch and discard monitoring program in the North Sea to estimate catch-ratios. We then rescale these catch-ratios and fit relationships to estimate gear efficiency. When catches of individuals by species were too low to enable species-specific estimates, gear efficiency was estimated for species-groups. Gear efficiency (and associated uncertainty) at length was ultimately estimated for 75 species, seven species-groups and for up to six types of trawl gear per species or species-group. Results are illustrated for dab (Limanda limanda), grey gurnard (Eutrigula gurnardus) and thornback ray (Raja clavata), two common non-target species and a depleted elasmobranch. All estimates of gear efficiency and uncertainty, by length, species, species-group and gear, are made available in a supplementary data file.

BIOLOGICAL MONITORING OF THE FORTIES OILFIELD (NORTH SEA)

1983 ◽  
Vol 1983 (1) ◽  
pp. 405-414 ◽  
Author(s):  
J. P. Hartley ◽  
J. Ferbrache
Keyword(s):  
North Sea ◽  
Biological Effects ◽  
Monitoring Program ◽  
Benthic Fauna ◽  
Sediment Type ◽  
The North ◽  
Naturally Occurring ◽  
The North Sea ◽  
Similar Survey ◽  
Benthic Sediments

ABSTRACT The Forties Oilfield (the largest in the U.K. sector of the North Sea) has been in production since September 1975. In June 1975, a quantitative survey of the benthic sediments and fauna over the area was made at the start of an environmental monitoring program for the field. The results of a repeat survey carried out after three years of production have been reported by Hartley.13 This paper presents data from a third similar survey in June 1981 and compares the findings with those of the earlier surveys. The benthic fauna of the Forties Field is rich and diverse and qualitatively corresponded well in 1981 to previous descriptions. Naturally occurring gradients in both the sediment type and fauna are a feature of this area. Changes in the densities of certain species were noted at some sites in 1981, including increases in certain opportunistic forms. Although no areas of biological effect could be delineated around the four production platforms, the industrial activity in the field may be implicated in the changes found at several stations. The hydrocarbon content of the sediments was low and, with one possible exception, did not appear related to the biological changes noted. The results to date suggest that offshore oilfields in deep water, developed using water-based drill fluids, present relatively few biological problems in the short term. Since no major biological effects have been found after six years of drilling and production, a reduced program of monitoring is recommended to maintain biological surveillance during the life of the field.

Compensatory Restoration of Mangrove Habitat Following the Tampa Bay Oil Spill

2001 ◽  
Vol 2001 (1) ◽  
pp. 761-767 ◽  
Author(s):  
Gary S. Mauseth ◽  
Jane S. Urquhart-Donnelly ◽  
Roy R. Lewis
Keyword(s):  
Mangrove Forest ◽  
Monitoring Program ◽  
Tampa Bay ◽  
Fuel Oil ◽  
Assessment Process ◽  
Performance Criteria ◽  
Disposal Site ◽  
The North ◽  
Dredge Spoil ◽  
Compensatory Restoration

ABSTRACT In 1993, an incident involving three vessels near the entrance to Tampa Bay, near St. Petersburg, Florida, resulted in a discharge approximately 300,000 gallons of No. 6. fuel oil into the waters off Egmont Key. The oil contacted the shores from Egmont Key to locations approximately 14 miles to the north. Oil also entered Boca Ciega Bay through John's Pass and impacted four small islands that supported mature overwash mangrove forest. A cooperative damage assessment process was developed between the Responsible Parties (RPs) and the trustees for the natural resources: the state of Florida, the National Oceanic and Atmospheric Administration (NOAA), and the U.S. Fish and Wildlife Service (USFWS). Through the cooperative process, several alternatives for primary and compensatory restoration were developed. In considering alternatives to compensate for impacts to epibenthic communities, fish and bird habitats, wetlands, and mangrove communities, the trustees and the RPs considered purchase of shoreline habitat and restoration of mangrove forest at several sites. The RP developed a proposal to purchase and deed into public ownership in perpetuity, a 10.67-acre parcel of land on the west bank of Cross Bayou in Boca Ciega Bay that had been used as a disposal site for dredge spoil in the past. This site consisted of approximately 5.0 acres of uplands, 4.4 acres of mangrove forest, and 1.4 acres of nonmangrove intertidal and subtidal habitat. The objective of the project was to establish a typical Tampa Bay mangrove forest and a roadside buffer free of exotic plant species. The secondary goals were to establish a typical Tampa Bay salt marsh dominated by smooth cordgrass (Spartina spp.) as a successional precursor to mangrove recruitment by seeds and seedlings. Tidal exchange through the site was reestablished to improve water quality and increase export of mangrove detritus and import of high-quality tidal waters. The project was designed and constructed by the RPs with the approval and supervision of the trustees. The project was completed and title transferred to Pinellas County, Florida in summer 1999. A monitoring program was developed and performance criteria established by trustee representatives and the RPs. The monitoring program currently is being conducted and has met performance criteria to date. This project demonstrates the positive result of trustees and the RPs working together to provide compensation to the environment.

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