The use of artificial oxygenation to reduce nutrient availability in the Canning River, Western Australia

2001 ◽  
Vol 43 (9) ◽  
pp. 133-144 ◽  
Author(s):  
B. Greenop ◽  
K. Lovatt ◽  
M. Robb
Keyword(s):  
Dissolved Oxygen ◽  
Water Column ◽  
Western Australia ◽  
Algal Blooms ◽  
Positive Impact ◽  
Monitoring Program ◽  
Nutrient Concentrations ◽  
Nitrogen And Phosphorus ◽  
The Impact ◽  
Oxygen Concentrations

Artificial oxygenation has been used for two summer periods to improve the water quality of the Canning River in Perth, Western Australia. The project is part of the Swan Canning Cleanup Program, which aims to reduce the frequency and severity of nuisance and toxic algal blooms in the Swan-Canning estuary. The trials have proved that oxygenation has increased the dissolved oxygen concentrations in the water column, particularly in the bottom waters where dissolved oxygen concentrations are frequently below a critical level of three milligrams per litre. Oxygenation has had a positive impact on nutrient concentrations in the water column and nitrogen cycling processes. Reductions in nutrient concentrations were highlighted by drops in ammonium and total phosphorus concentrations of 97% and 64% following the recommencement of oxygenation after a plant shutdown. Results of a microbiological study combined with the data analysis indicate that the number of nitrifying microbes have increased due to oxygenation. However, comparisons between oxygenated and control areas were inconclusive about the ability of the oxygenation plant to reduce total nitrogen and phosphorus levels. This could be explained by factors such as spatial variability, water flow during the trials and measurement limitations in the monitoring program. Future work will concentrate on assessing the impact of the oxygenation plant on nutrient concentrations.

scholarly journals Occurrence of Ceratium furcoides (Levander) Langhans 1925 bloom at the Billings Reservoir, São Paulo State, Brazil

2010 ◽  
Vol 70 (3 suppl) ◽  
pp. 825-829 ◽  
Author(s):  
T Matsumura-Tundisi ◽  
JG Tundisi ◽  
AP Luzia ◽  
RM Degani
Keyword(s):  
Water Treatment ◽  
Dissolved Oxygen ◽  
Water Column ◽  
Dominant Species ◽  
Nutrient Concentrations ◽  
Phosphorus Concentration ◽  
Fish Kill ◽  
Nitrogen And Phosphorus ◽  
Paulo State ◽  
Cold Fronts

An unusual bloom of Ceratium furcoides is reported for a station of the Taquacetuba compartment of the Billings Reservoir. The appearance of this bloom is attributed to the mixing and turbulence of the water column that removed Ceratium cysts from the surface of the sediment and promoted conditions for the growth of this species in the region of mixing. Cold fronts approaching the Billings Reservoir are probably the cause of the mixing and bloom. Also turbulence induced by wind increased phosphorus concentration in the water column. Ceratium furcoides was the dominant species at station 1 where the nutrient concentrations of nitrogen and phosphorus were high. Ceratium spp. blooms may be a problem for water treatment and massive mortality can affect the dissolved oxygen of the water producing fish kill.

scholarly journals A Review of Nontraditional Biomanipulation

2008 ◽  
Vol 8 ◽  
pp. 1184-1196 ◽  
Author(s):  
Xia Zhang ◽  
Ping Xie ◽  
Xiaoping Huang
Keyword(s):  
Algal Blooms ◽  
Algal Species ◽  
Planktivorous Fish ◽  
Bighead Carp ◽  
Cyanobacterial Blooms ◽  
Management Tool ◽  
Nutrient Concentrations ◽  
Effective Management ◽  
Nuisance Algae ◽  
The Impact

The aim of this review is to identify problems, find general patterns, and extract recommendations for successful management using nontraditional biomanipulation to improve water quality. There are many obstacles that prevent traditional biomanipulation from achieving expectations: expending largely to remove planktivorous fish, reduction of external and internal phosphorus, and macrophyte re-establishment. Grazing pressure from large zooplankton is decoupled in hypereutrophic waters where cyanobacterial blooms flourish. The original idea of biomanipulation (increased zooplankton grazing rate as a tool for controlling nuisance algae) is not the only means of controlling nuisance algae via biotic manipulations. Stocking phytoplanktivorous fish may be considered to be a nontraditional method; however, it can be an effective management tool to control nuisance algal blooms in tropical lakes that are highly productive and unmanageable to reduce nutrient concentrations to low levels.Although small enclosures increase spatial overlap between predators and prey, leading to overestimates of the impact of predation, microcosm and whole-lake experiments have revealed similar community responses to major factors that regulate lake communities, such as nutrients and planktivorous fish. Both enclosure experiments and large-scale observations revealed that the initial phytoplankton community composition greatly impacted the success of biomanipulation. Long-term observations in Lake Donghu and Lake Qiandaohu have documented that silver carp (Hypophthalmichthys molitrix) and bighead carp (H. nobilis) (two filter-feeding planktivorous species commonly used in management) can suppress Microcystis blooms efficiently. The introduction of silver and bighead carp could be an effective management technique in eutrophic systems that lack macrozooplankton. We confirmed that nontraditional biomanipulation is only appropriate if the primary aim is to reduce nuisance blooms of large algal species, which cannot be controlled effectively by large herbivorous zooplankton. Alternatively, this type of biomanipulation did not work efficiently in less eutrophic systems where nanophytoplankton dominated.

Controls on oxygen response to climate change on the Northwest European Continental Shelf

2020 ◽  
Author(s):  
Sarah L. Wakelin ◽  
Yuri Artioli ◽  
Momme Butenschön ◽  
Jason Holt ◽  
Jeremy Blackford
Keyword(s):  
Climate Change ◽  
Continental Shelf ◽  
Water Column ◽  
Ecosystem Processes ◽  
Phytoplankton Production ◽  
Biogeochemical Model ◽  
Biological Cycling ◽  
Increasing Temperature ◽  
The Impact ◽  
Oxygen Concentrations

<p>Dissolved oxygen in the ocean is an indicator of water quality and low concentrations can threaten ecosystem health. The main sources of marine oxygen are diffusion from the atmosphere and phytoplankton photosynthesis. Biological respiration and decomposition act to reduce oxygen concentrations. Under conditions of vertical stratification, the water column below the pycnocline is isolated from oxygen exchange with the atmosphere, photosynthesis may be limited by light availability and oxygen concentrations decrease. Climate change influences the oxygen cycle in two ways: 1) changing the hydrodynamic climate and 2) affecting rates of biogeochemical processes. The hydrodynamic climate affects the nutrient supply and so controls phytoplankton production while changes to water column stratification affects vertical mixing. Gas solubility decreases with increasing temperature so that oxygen uptake from the atmosphere is expected to decrease under increasing oceanic temperatures. Biological cycling rates increase with increasing temperature affecting photosynthesis, respiration and bacterial decomposition. It is not obvious whether changes in oxygen concentrations due to changing ecosystem processes will mitigate or reinforce the projected reduction from solubility changes.</p><p>The Northwest European Continental shelf (NWES) is a region of the northeast Atlantic that experiences seasonal stratification. We use the physics-biogeochemical model NEMO-ERSEM to study near-bed oxygen concentrations on the NWES under a high greenhouse gas emissions scenario (Representative Concentration Pathway (RCP) 8.5). We show that much of the NWES could experience low oxygen concentrations by 2100 and assess the relative impacts of changing temperature and ecosystem processes. Until about 2040 the impact of solubility dominates the oxygen change. The mean near-bed oxygen concentration is projected to decrease by 6.3% by 2100, of which 73% is due to solubility changes and the remainder to changes in the ecosystem. In the oxygen-depleted region in the eastern North Sea, 77% of the near-bed oxygen reduction is due to ecosystem processes.</p>

The Impact of Post Anoxic Dissolved Oxygen Concentrations on nitrous Oxide Emissions in Nitrification Processes

2011 ◽  
Vol 2011 (9) ◽  
pp. 6494-6499
Author(s):  
Muriel Dumit ◽  
Jordi Gabarró ◽  
Sudhir Murthy ◽  
Rumana Riffat ◽  
Bernhard Wett ◽  
...  
Keyword(s):  
Nitrous Oxide ◽  
Dissolved Oxygen ◽  
Nitrous Oxide Emissions ◽  
The Impact ◽  
Oxygen Concentrations

The Case for Phosphorus

Dead Zones ◽  
2021 ◽  
pp. 106-123
Author(s):  
David L. Kirchman
Keyword(s):  
Harmful Algal Blooms ◽  
Algal Blooms ◽  
Wastewater Treatment Plants ◽  
Action Plan ◽  
Dead Zone ◽  
Cyanobacterial Blooms ◽  
Nutrient Concentrations ◽  
Marine Microorganisms ◽  
Nitrogen And Phosphorus ◽  
The Baltic

As this chapter explains, one approach to evaluate nutrient limitation is to compare nutrient concentrations with the Redfield ratio. Alfred Redfield had no formal background in oceanography, yet he made one of the most fundamental discoveries in the field. He found that the ratio of nitrogen to phosphorus in marine microorganisms is the same as the ratio of the two elements in nutrients dissolved in the oceans. Because of work with the ratio, the current Hypoxia Action Plan for the Gulf of Mexico mentions phosphorus as well as nitrogen. In the Baltic Sea, it was argued that the focus should be solely on phosphorus to limit toxic cyanobacterial blooms, but other work demonstrates the importance of limiting nitrogen for minimizing eutrophication. Once considered to be a dead lake, Lake Erie improved after the construction of wastewater-treatment plants and the banning of phosphorus-rich detergents, as the chapter shows. But the lake continues to have problems with hypoxia and harmful algal blooms, because of continuing inputs of phosphate and organic nitrogen. The chapter ends by arguing that both nitrogen and phosphorus must be considered in efforts to solve the dead-zone problem.

Monitoring Effects of Drought on Nitrogen and Phosphorus in Temperate Oak Forests Using Machine Learning Techniques

2018 ◽  
Author(s):  
Jan Kotlarz ◽  
Katarzyna Kubiak ◽  
Marcin Spiralski
Keyword(s):  
Machine Learning ◽  
Drought Stress ◽  
Negative Impact ◽  
Aerial Images ◽  
Machine Learning Techniques ◽  
Nutrient Concentrations ◽  
Nitrogen And Phosphorus ◽  
Learning Techniques ◽  
The Impact

Oak is a European tree species highly sensitive to drought. If declining symptoms appear they are often detectable at the crown (such as dieback) enabling monitoring using aerial images and remote sensing methods. Here, we analyzed the impact of short and long-term drought on oaks located in central Poland, between the years of 2014 and 2017. We used leaf nitrogen (N) and phosphorus (P) concentrations measured in the laboratory, aerial images collected in the range of 460-880 nm and machine learning techniques to estimate nutrient concentrations on the > 4000 oaks growing on gleysoil in the study area. We determined a negative impact on N and P concentrations during both types of drought stress (-23% and 19% for N concentration in leaves; -27% and -10% for P concentration in leaves) and an inconsiderable impact on N:P values (3% increase of N:P ration during short and 7% decrease of N:P ration during long-term drought stress). We found that the long-term drought impact was spatially diverse, possibly depending on the presence of drainage ditches and competing species.

scholarly journals Monitoring a newly re-born patient: water quality and cyanotoxin occurrence in a reconstructed shallow Mediterranean lake

2017 ◽  
Vol 8 (1) ◽  
Author(s):  
Spyros Gkelis ◽  
Manthos Panou ◽  
Ioannis Chronis ◽  
Sevasti-Kiriaki Zervou ◽  
Christophoros Christophoridis ◽  
...  
Keyword(s):  
Water Quality ◽  
Algal Blooms ◽  
Monitoring Program ◽  
Molecular Techniques ◽  
Mitigation Measures ◽  
Cylindrospermopsis Raciborskii ◽  
Lake Ecosystem ◽  
Land Uses ◽  
The Impact ◽  
Lake Karla

Lake Karla (Central Greece) is a unique example - at European scale - of a shallow lake ecosystem that was dried in the 1960s and in 2009 started to be restored. The lake is listed in the network of the Greek protected areas as it is considered a vital aquatic ecosystem, in terms of biodiversity. It has, however, already been adversely affected by both agricultural and industrial land uses in the surrounding area, leading to eutrophication and shifting algal community towards bloom-forming toxic cyanobacterial species. After repeated heavy-blooms, cyanotoxin occurrence and mass fish kills, the local ecosystem management authority has implemented a water quality monitoring program (July 2013 - July 2015) to assess environmental pressures and the response of aquatic biota in the lake. Microscopic, immunological, and molecular techniques combined with physico-chemical parameters, complemented by liquid chromatography tandem mass spectrometry (LC-MS/MS), were used to monitor cyanobacteria blooms and the associated cyanotoxin production from three different sites in Lake Karla and from the adjacent Kalamaki Reservoir. Water quality was also assessed by the structure of benthic invertebrate community on the sediment. Cyanobacteria were the main phytoplankton component, representing more than 70% of the total phytoplankton abundance; dominant taxa belonged to Cylindrospermopsis raciborskii, Limnothrix redekei, Anabaenopsis elenkinii, and Microcystis spp. Euglenophytes (Euglena), diatoms (Nitzschia), and chlorophytes (Scenedesmus) were also important phytoplankton constituents. LC-MS/MS confirmed the co-occurrence of microcystins, cylindrospermopsin, saxitoxin, neo-saxitoxin and anatoxin-a. The occurrence of cyanotoxins in relation to the persistent and dominant cyanobacteria and the impact of cyanobacterial harmful algal blooms on the newly constructed lake along with the land uses and the emergent mitigation measures are discussed. 

The relationship between sediment and water quality, and riverine sediment loads in the wave-dominated estuaries of south-west Western Australia

2004 ◽  
Vol 55 (6) ◽  
pp. 581 ◽  
Author(s):  
L. C. Radke ◽  
I. P. Prosser ◽  
M. Robb ◽  
B. Brooke ◽  
D. Fredericks ◽  
...  
Keyword(s):  
Water Quality ◽  
Organic Matter ◽  
Soil Erosion ◽  
Organic Carbon ◽  
Water Column ◽  
Nitrogen And Phosphorus ◽  
Weathering Index ◽  
Sediment Loads ◽  
The Impact ◽  
Column Total

We examine surface sediment and water column total nutrient and chlorophyll a concentrations for 12 estuaries with average water depths <4 m, and calculated sediment loads ranging from 0.2 to 10.8 kg m−2 year−1. Sediment total nitrogen, phosphorus and organic carbon concentrations vary inversely with sediment loads due to: (i) the influx of more mineral-rich sediment into the estuaries; and (ii) increasing sediment sulfidation. Sediment total organic carbon (TOC) : total sulfur (TS) and TS : Fe(II) ratios correlated to sediment loads because enhanced sedimentation increases burial, hence the importance of sulfate reduction in organic matter degradation. Curvilinear relationships were found between a weathering index and organic matter δ13C in sediment, and sediment load. The rising phase of the curve (increasing weathering, lighter isotopic values) at low to intermediate loads relates to soil erosion, whereas regolith or bedrock erosion probably explains the declining phase of the curve (decreasing weathering, heavier isotopic values) at higher sediment loads. The pattern of change for water column total nutrients (nitrogen and phosphorus) with sediment loads is similar to that of the weathering index. Most water quality problems occur in association with soil erosion, and at sediment loads that are intermediate for the estuaries studied. Limited evidence is presented that flushing can moderate the impact of sediment loads upon the estuaries.

scholarly journals Trends, insights and effects of the Urban Wastewater Treatment Directive (91/271/EEC) implementation in the light of the Polish coastal zone eutrophication

2021 ◽  
Vol 67 (2) ◽  
pp. 342-354
Author(s):  
Michał Preisner ◽  
Marzena Smol ◽  
Dominika Szołdrowska
Keyword(s):  
Wastewater Treatment ◽  
Baltic Sea ◽  
Algal Blooms ◽  
Municipal Wastewater ◽  
Nutrient Concentrations ◽  
Urban Wastewater ◽  
The Baltic Sea ◽  
Nitrogen And Phosphorus ◽  
The Baltic ◽  
Urban Wastewater Treatment

AbstractThe intensification of the Baltic Sea eutrophication is associated with the increase of anthropogenic nutrients loads, mainly nitrogen and phosphorus introduced into surface waters from a diffuse, point and natural background sources. Despite the observed decreasing trends in nutrient concentrations in some parts of the Baltic Sea, eutrophication-related indicators continue to deteriorate. This accelerates harmful algal blooms and dissolved oxygen deficits resulting in severe ecosystem disturbance. The paper presents trends, insights and effects of the Urban Wastewater Treatment Directive 91/271/EEC implementation in Poland based on the nutrient riverine loads from Polish territory with particular attention given to the development of municipal wastewater treatment plants under the National Wastewater Treatment Programme 2003–2016. Environmental effects of wastewater infrastructure modernisation are investigated by using available data on the changing nutrient concentrations in the coastal water in 3 basins (Gdansk Basin, Bornholm Basin and Eastern Gotland Basin) belonging to the Polish Exclusive Economic Zone within the Baltic Sea. The results show that the decreasing trend regarding phosphorus loads reduction from municipal effluents was achieved while a stable trend with temporary increases was achieved in terms of nitrogen loads. Moreover, the investigation provides information about the potential bioavailability of discharged effluents before and after the Directive implementation by including total and inorganic forms of nitrogen and phosphorus in the analysis.

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