scholarly journals Mini-Hydrocyclone Separation of Cyanobacterial and Green Algae: Impact on Cell Viability and Chlorine Consumption

Water ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 1473
Author(s):  
Saber Moradinejad ◽  
Dries Vandamme ◽  
Caitlin M. Glover ◽  
Tahere Zadfathollah Seighalani ◽  
Arash Zamyadi
Keyword(s):  
Green Algae ◽  
Harmful Algal Blooms ◽  
Algal Blooms ◽  
Separation Efficiency ◽  
Scenedesmus Obliquus ◽  
Free Chlorine ◽  
Feed Water ◽  
Toxic Species ◽  
Water Matrix ◽  
The Impact

The co-occurrence of non-toxic phytoplankton alongside cyanobacteria adds to the challenge of treating source waters with harmful algal blooms. The non-toxic species consume the oxidant and, thereby, reduce the efficacy of oxidation of both the extracellular and intracellular cyanotoxins. In this work, a 3D printed mini-hydrocyclone was used to separate a mixture of non-toxic green algae, Scenedesmus obliquus, from a toxic species of cyanobacteria, Microcystis aeruginosa. When water is pumped through the mini-hydrocyclone, cells exit through an overflow or underflow port depending on their size, shape, and density relative to the other cells and particles in the water matrix. The overflow port contains the cells that are smaller and less dense since these particles move toward the center of the hydrocyclone. In this work, the majority (>93%) of Microcystis cells were found in the overflow while the underflow contained primarily the Scenedesmus (>80%). This level of separation efficiency was maintained over the 30-min experiment and the majority of both cells (>86%) remained viable following the separation, which indicates that the pumping combined with forces exerted within the mini-hydrocyclone were not sufficient to cause cell death. The impact of free chlorine on the cells both pre-separation and post-separation was evaluated at two doses (1 and 2 mg/L). After separation, the overflow, which contained primarily Microcystis, had at least a 24% reduction in the free chlorine decay rate as compared to the feed water, which contained both species. This reduction in chlorine consumption shows that the cells separated via mini-hydrocyclone would likely require lower doses of oxidant to produce a similar level of degradation of the cyanotoxins present in either the extracellular or intracellular form. However, future work should be undertaken to evaluate this effect in natural bloom samples.

scholarly journals Effects of the Marine Biotoxins Okadaic Acid and Dinophysistoxins on Fish

2021 ◽  
Vol 9 (3) ◽  
pp. 293
Author(s):  
Mauro Corriere ◽  
Lucía Soliño ◽  
Pedro Reis Costa
Keyword(s):  
Okadaic Acid ◽  
Harmful Algal Blooms ◽  
Algal Blooms ◽  
Current Knowledge ◽  
Global Climate ◽  
Scientific Evidence ◽  
Shellfish Poisoning ◽  
Morphological Alterations ◽  
The Impact ◽  
Dsp Toxins

Natural high proliferations of toxin-producing microorganisms in marine and freshwater environments result in dreadful consequences at the socioeconomically and environmental level due to water and seafood contamination. Monitoring programs and scientific evidence point to harmful algal blooms (HABs) increasing in frequency and intensity as a result of global climate alterations. Among marine toxins, the okadaic acid (OA) and the related dinophysistoxins (DTX) are the most frequently reported in EU waters, mainly in shellfish species. These toxins are responsible for human syndrome diarrhetic shellfish poisoning (DSP). Fish, like other marine species, are also exposed to HABs and their toxins. However, reduced attention has been given to exposure, accumulation, and effects on fish of DSP toxins, such as OA. The present review intends to summarize the current knowledge of the impact of DSP toxins and to identify the main issues needing further research. From data reviewed in this work, it is clear that exposure of fish to DSP toxins causes a range of negative effects, from behavioral and morphological alterations to death. However, there is still much to be investigated about the ecological and food safety risks related to contamination of fish with DSP toxins.

scholarly journals Fish Kill Incidents and Harmful Algal Blooms in Omani Waters

2011 ◽  
Vol 16 ◽  
pp. 23 ◽  
Author(s):  
Hamed Mohammed Al Gheilani ◽  
Kazumi Matsuoka ◽  
Abdulaziz Yahya AlKindi ◽  
Shehla Amer ◽  
Colin Waring
Keyword(s):  
Harmful Algal Blooms ◽  
Algal Blooms ◽  
Red Tide ◽  
Ecological Impacts ◽  
Red Tides ◽  
Fish Kill ◽  
Noctiluca Scintillans ◽  
Trichodesmium Erythraeum ◽  
Toxic Species ◽  
Desalination Plants

Red tide, one of the harmful algal blooms (HABs) is a natural ecological phenomenon and often this event is accompanied by severe impacts on coastal resources, local economies, and public health. The occurrence of red tides has become more frequent in Omani waters in recent years. Some of them caused fish kill, damaged fishery resources and mariculture, threatened the marine environment and the osmosis membranes of desalination plants. However, a number of them have been harmless. The most common dinoflagellate Noctiluca scintillans is associated with the red tide events in Omani waters. Toxic species like Karenia selliformis, Prorocentrum arabianum, and Trichodesmium erythraeum have also been reported recently. Although red tides in Oman have been considered a consequence of upwelling in the summer season (May to September), recent phytoplankton outbreaks in Oman are not restricted to summer. Frequent algal blooms have been reported during winter (December to March). HABs may have contributed to hypoxia and/or other negative ecological impacts. 

scholarly journals Comparison of Short-Term Toxicity of 14 Common Phycotoxins (Alone and in Combination) To The Survival of Brine Shrimp Artemia Salina

2021 ◽  
Author(s):  
Yu Ting Zhang ◽  
Shanshan SONG ◽  
Bin ZHANG ◽  
Yang ZHANG ◽  
Miao TIAN ◽  
...  
Keyword(s):  
Ecological Risk ◽  
Harmful Algal Blooms ◽  
Algal Blooms ◽  
Algal Species ◽  
Natural Populations ◽  
Marine Ecosystems ◽  
Artemia Salina ◽  
Marine Organisms ◽  
Short Term ◽  
The Impact

Abstract Toxic harmful algal blooms (HABs) can cause deleterious effects in marine organisms, threatening the stability of marine ecosystems. It is well known that different strains, natural populations and growth conditions of the same toxic algal species may lead to different amount of phycotoxin production and the ensuing toxicity. To fully assess the ecological risk of toxic HABs, it is of great importance to investigate the toxic effects of phycotoxins in marine organisms. In this study, the short-term toxicity of 14 common phycotoxins (alone and in combination) in the marine zooplankton Artemia salina was investigated. On the basis of 48 h LC50, the order of toxicity in A. salina was AZA3 (with a LC50 of 0.0203 µg/ml)＞AZA2 (0.0273 µg/ml) ＞PTX2 (0.0396 µg/ml)＞DTX1 (0.0819 µg/ml)＞AZA1 (0.106 µg/ml)＞ SPX1 (0.144 µg/ml)＞YTX (0.172 µg/ml)＞dcSTX (0.668 µg/ml)＞OA (0.728 µg/ml)＞STX (1.042 µg/ml)＞GYM (1.069 µg/ml)＞PbTx3 (1.239 µg/ml)＞hYTX (1.799 µg/ml)＞PbTx2 (2.415 µg/ml). For the binary exposure, additive effects of OA and DTX1, DTX1 and hYTX; antagonistic effects of OA and PTX2, OA and STX; and synergetic effects of DTX1 and STX, DTX1 and YTX, DTX1 and PTX2, PTX2 and hYTX on the mortality of A. salina were observed. These results provide valuable toxicological data for assessing the impact of phycotoxins on marine planktonic species and highlight the potential ecological risk of toxic HABs in marine ecosystems.

scholarly journals Environmental Considerations for the Management of the Bivalve Fisheries of Bahía Magdalena (Mexico), a Coastal Lagoon at the Southern End of the California Current

2021 ◽  
Vol 8 ◽  
Author(s):  
María del Carmen Jiménez-Quiroz ◽  
Francisco Javier Barrón-Barraza ◽  
Rafael Cervantes-Duarte ◽  
René Funes-Rodríguez
Keyword(s):  
Harmful Algal Blooms ◽  
Algal Blooms ◽  
Large Scale ◽  
Environmental Variability ◽  
Southern Oscillation ◽  
Warming Trend ◽  
Regional Warming ◽  
Biological Variables ◽  
The Impact ◽  
Bahia Magdalena

This study presents an overview of bivalve assemblages in Bahia Magdalena (BM, México) and the possible impact of environmental variability on these populations, constantly stressed by fishing. This lagoon is responsible for a high proportion of harvest of regional bivalves. First, we list the bivalve species reported in public biogeographic databases. Based on eight commercially exploited species, we described the composition of the bivalve assemblage and its biological characteristics, the history of fishery, and environmental variability in the marine area adjacent to the lagoon (1970–2019) and the habitat of bivalves (2002–2020). Sources of data were public databases and published literature. The enlisted species (n = 184) belong to six orders, and most are small and infaunal, but the structure of the assemblage is unknown. The fisheries began at different times and focused on the most valuable resources. Almost all harvest of bivalves had wide variations because of intensive fishing and a weak regulation frame. After 2015, the main resources were the Pacific wing-oyster (a new resource since 2017) and the geoduck clam due to the declining abundance of other resources (e.g., pen shells, Pacific calico scallop). There was a warming trend in the region since the 1970's, but the strongest El Niño-Southern Oscillation (ENSO) phases caused the most notable changes before 2013; after that year, a combination of large-scale phenomena increased the temperature significantly. The trend of chlorophyll-a abundance negatively correlated with temperature, but there was an almost constant supply of particulate organic matter in the interior of Bahia Magdalena (BM). After 2015, the quality of lagoon water gradually deteriorated, and in 2017 and 2019, harmful algal blooms developed, but the impact was not fully assessed. The challenges faced by the fishery are multiple (institutional weakness and regional warming); however, permanent monitoring programs of environmental conditions and critical biological variables should be implemented to design scenarios that allow fishery sustainability.

scholarly journals Monitoring approaches for supporting offshore aquaculture management and EU Directives at Sagres, Portugal

2016 ◽  
Author(s):  
Bruno Dias Duarte Fragoso ◽  
John David Icely ◽  
Nancy Odour ◽  
Gerald Moore ◽  
João Magalhães Neto ◽  
...  
Keyword(s):  
Harmful Algal Blooms ◽  
Algal Blooms ◽  
Secchi Depth ◽  
Aquaculture Management ◽  
Additional Water ◽  
Eu Directives ◽  
Routine Sampling ◽  
Offshore Aquaculture ◽  
Maritime Spatial Planning ◽  
The Impact

The increasing development of aquaculture activity in the coast of Sagres, area included in the Parque Natural do Sudoeste Alentejano e Costa Vicentina (PNSACV) SW Portugal, has to comply with regional and national regulations. The development also has to comply with EU directives including: Quality of Shellfish Waters Directive 2006/113/EC (QSWD); Water Framework Directive 2000/60/EC (WFD); Marine Strategy Framework Directive 2008/56/EC (MSFD); Maritime Spatial Planning 2014/89/EU, (MSP). During 2014/2015, a monitoring routine was established to assess the potential impact of aquaculture in the region, as required by the Agência Portuguesa do Ambiente (APA). This involved a weekly sampling routine of water parameters at surface and bottom, including temperature (SST), salinity (Sal), Secchi depth, chlorophyll (Chl), suspended particulate matter (SPM), pH, oxygen (O2) and nutrients. Additional water samples were collected for phytoplankton counts to provide information on the species contributing to Harmful Algal Blooms (HABs). Associated with the routine sampling, innovative approaches to understanding the impact of aquaculture have been undertaken including: use of remote sensing products to provide spatial and temporal data for SST, Sal, Chl, and SPM validated with in situ radiometric data (Satlantic and WISP-3); genomics for HABs and flow cytometry for nanoplankton; a survey of impact on the benthos; determination of nutrient condition in the region through nutrient stoichiometry; automisation of data collection with an oceanographic buoy. Preliminary data from both routine and innovative studies will be presented in relation to aquaculture management and to the requirements of the WFD and the MSFD.

Algal Communities as a Biological Indicator of Stormwater Management Pond Performance and Function

2000 ◽  
Vol 35 (3) ◽  
pp. 489-504 ◽  
Author(s):  
Daniel D. Olding
Keyword(s):  
Green Algae ◽  
Stormwater Management ◽  
Harmful Algal Blooms ◽  
Algal Blooms ◽  
Biological Indicator ◽  
Taxonomic Composition ◽  
Algal Community ◽  
Algal Communities ◽  
Blue Green Algae ◽  
Biological Communities

Abstract An investigation into phytoplankton and periphyton algal communities of two recently constructed Stormwater management ponds suggests that Stormwater impacts on biological communities are reduced during passage through the ponds, providing a degree of protection for biological communities in their receiving waters. In both ponds, disturbance effects from the incoming Stormwater on algal community richness and evenness appear to be greatest in the sediment forebay and are reduced in the main pond. However, the nature of the disturbance in the two systems can be seen to be fundamentally different from a biological perspective, with Rouge Pond functioning primarily to reduce toxins harmful to algal communities (e.g., heavy metals), and Harding Pond acting to reduce nutrients. The taxonomic composition of the two sites provides an indication of the quality of the incoming Stormwater. Rouge Pond, which contains many marine and brackish water species, receives Stormwater runoff from a major highway, while Harding Pond, containing more nutrient rich species, receives Stormwater primarily from residential properties. Despite the nutrient-rich conditions present in both ponds, nuisance blue-green algae (cyanobacte-ria) are conspicuously absent, and the ponds appear to have little potential for developing harmful algal blooms. The lack of blue-green algae can be linked to the hydraulic functioning of the ponds, suggesting that Stormwater facilities may be engineered to inhibit undesirable algal communities.

scholarly journals The rise in climate change-induced federal fishery disasters in the United States

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e11186
Author(s):  
Lyall Bellquist ◽  
Vienna Saccomanno ◽  
Brice X. Semmens ◽  
Mary Gleason ◽  
Jono Wilson
Keyword(s):  
Climate Change ◽  
United States ◽  
Harmful Algal Blooms ◽  
Algal Blooms ◽  
Ad Hoc ◽  
The United States ◽  
Societal Benefit ◽  
Disaster Assistance ◽  
Environmental Events ◽  
The Impact

Commercial, recreational, and indigenous fisheries are critical to coastal economies and communities in the United States. For over three decades, the federal government has formally recognized the impact of fishery disasters via federal declarations. Despite these impacts, national syntheses of the dynamics, impacts, and causes of fishery disasters are lacking. We developed a nationwide Federal Fishery Disaster database using National Oceanic and Atmospheric Administration (NOAA) fishery disaster declarations and fishery revenue data. From 1989-2020, there were 71 federally approved fishery disasters (eleven are pending), which spanned every federal fisheries management region and coastal state in the country. To date, we estimate fishery disasters resulted in $2B (2019 USD) in Congressional allocations, and an additional, conservative estimate of $3.2B (2019 USD) in direct revenue loss. Despite this scale of impact, the disaster assistance process is largely ad hoc and lacks sufficient detail to properly assess allocation fairness and benefit. Nonetheless, fishery disasters increased in frequency over time, and the causes of disasters included a broad range of anthropogenic and environmental factors, with a recent shift to disasters now almost exclusively caused by extreme environmental events (e.g., marine heatwaves, hurricanes, and harmful algal blooms). Nationwide, 84.5% of fishery disasters were either partially or entirely attributed to extreme environmental events. As climate change drives higher rates of such extreme events, and as natural disaster assistance requests reach an all-time high, the federal system for fisheries disaster declaration and mitigation must evolve in order to effectively protect both fisheries sustainability and societal benefit.

scholarly journals Harmful Algal Blooms (HABS) along Mexican Coasts

2018 ◽  
Author(s):  
Magnolia Gricel Salcedo-Garduño ◽  
María del Refugio Castañeda-Chávez ◽  
Fabiola Lango-Reynoso ◽  
Itzel Galaviz-Villa
Keyword(s):  
Public Health ◽  
Harmful Algal Blooms ◽  
Algal Blooms ◽  
Anthropogenic Factors ◽  
Environment And Public Health ◽  
Negative Effects ◽  
Direct Exposure ◽  
Public Health Strategies ◽  
Toxic Bloom ◽  
The Impact

Harmful algal blooms (HABs) are natural events produced by massive concentration of toxic phytoplankton that can color red, ocher, brown or yellow large extensions of water, its intensity depends on the different species of phytoplankton involved in the proliferation. The spreading of these formations involves an interaction of biological, chemical, meteorological and anthropogenic factors. Several species with potential toxicity have been reported along Mexican coasts, such as Gymnodinium catenatum, Karenia brevis, Pyrodinium bahamense var. compressum. The toxic bloom not only causes an impact during the event, it produces negative effects afterward, such as accumulating deposits of organic matter, alterations of benthic community structure and composition, species presence/absence, and bioaccumulation of toxins in organisms such as bivalve molluscs mainly. Poisoning may occur by consuming contaminated seafood or by direct exposure to aerosols of the toxins, which can provoke diarrhea or even death. Due to the impact of this type of event on the economy, environment and public health, strategies for monitoring, prevention, and systematic mitigation have been implemented for the evaluation of HAB effects. The aim of this review was to determine the state-of-the art of HAB, their reports and effects on the environment and public health in Mexico.

scholarly journals Intraspecific facilitation by allelochemical mediated grazing protection within a toxigenic dinoflagellate population

2015 ◽  
Vol 282 (1798) ◽  
pp. 20141268 ◽  
Author(s):  
Uwe John ◽  
Urban Tillmann ◽  
Jennifer Hülskötter ◽  
Tilman J. Alpermann ◽  
Sylke Wohlrab ◽  
...  
Keyword(s):  
Harmful Algal Blooms ◽  
Algal Blooms ◽  
Phenotypic Diversity ◽  
Marine Ecosystem ◽  
Paralytic Shellfish Poisoning ◽  
Alexandrium Tamarense ◽  
Shellfish Poisoning ◽  
Coastal Marine ◽  
The Impact ◽  
Intraspecific Facilitation

Dinoflagellates are a major cause of harmful algal blooms (HABs), with consequences for coastal marine ecosystem functioning and services. Alexandrium fundyense (previously Alexandrium tamarense ) is one of the most abundant and widespread toxigenic species in the temperate Northern and Southern Hemisphere and produces paralytic shellfish poisoning toxins as well as lytic allelochemical substances. These bioactive compounds may support the success of A. fundyense and its ability to form blooms. Here we investigate the impact of grazing on monoclonal and mixed set-ups of highly (Alex2) and moderately (Alex4) allelochemically active A. fundyense strains and a non-allelochemically active conspecific (Alex5) by the heterotrophic dinoflagellate Polykrikos kofoidii . While Alex4 and particularly Alex5 were strongly grazed by P. kofoidii when offered alone, both strains grew well in the mixed assemblages (Alex4 + Alex5 and Alex2 + Alex5). Hence, the allelochemical active strains facilitated growth of the non-active strain by protecting the population as a whole against grazing. Based on our results, we argue that facilitation among clonal lineages within a species may partly explain the high genotypic and phenotypic diversity of Alexandrium populations. Populations of Alexandrium may comprise multiple cooperative traits that act in concert with intraspecific facilitation, and hence promote the success of this notorious HAB species.

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