Red Tide Phenomena Research Articles

The Abundance of Gonyaulax polygramma and Chaetoceros sp. Causing Blooming in Ambon Bay, Maluku

This study examines the first occurrence of non-toxic dinoflagellate blooming of Gonyaulax polygramma and Chaetoceros sp in Ambon Bay that occurred for almost three weeks in January 2019 and it caused the watercolor became red brown. The objective of this study was to identified phytoplankton species and their abundance that cause red tide in the Inner Ambon bay. Phytoplankton samples were collected, temperature, salinity and Secchi depth were measured simultaneously on the 11th and 21st January 2019 (nortwest monsoon) at fifteen sampling stations in Inner Ambon Bay. The results show that the maximum abundance of Gonyaulax polygramma, Chaetoceros affinis, C. danicus and C. decipiens were found in the greatest concentration up to 20×109, 9.0x106, 5.8x106 and 3.8x105 cells.L-1, respectively. They were found either in the form of a single cell or in chains. The very high abundance of cells of those species made the waters become red brown but there was no reports of fish killed during this red tide phenomena. This is the first time report of blooming phytoplankton Gonyaulax polygramma, Chaetoceros affinis, C. danicus and C. decipiens occurred in Ambon bay during the dry season where the recorded waters temperature and salinity ranged from 30-32ºC and 29-33 psu, respectively and the secchi depths ranged from 2 to 6m.

Phytoplankton and bacterial community structures and their interaction during red-tide phenomena

Phytoplankton and bacteria diversity were studied before, during and after red tide phenomena during spring season 2015 in the Eastern Harbour (E.H.) of Alexandria, Egypt. Fifty five species of phytoplankton were identified and represented different distinct classes “Bacillariophyceae; Dinophyceae, Chlorophyceae, Cyanophyceae and Eugelenophyceae”. Also, Diatom formed the most dominant group. The average number of the phytoplankton density varied from 4.8 × 104 to 1.1 × 106 cell l-1 during the study period and Skeletonema costatum was the agent causing the red tide. The existence percentages of bacteria ranged from 2.6 to 17.9% on all media tested. The bacterial isolates on the nutrient agar medium represented the highest existence with a total percentage of 43.6%, followed by MSA medium (25.7%), while the lowest percentage was for the AA medium at 7.8%. However, twelve isolates were selected as representative for bacterial community during study interval. Based on the morphological, biochemical, physiological and enzymatic characteristics, the bacterial strains were described. Depending on the 16S rDNA gene sequence, three common antagonists were aligned as: Vibrio toranzoniae strain Vb 10.8, Ruegeria pelagia strain NBRC 102038 and Psychrobacter adeliensis strain DSM 15333. The interaction between these bacteria and S. costatum was studied. The growth of S. costatum was significantly lower whenever each bacterium was present as compared to axenic culture. More specifically, 30% (v/v) of the all tested bacteria showed the strongest algicidal activities, as all S. costatum cells were killed after two days. 10% of R. pelagia and P. adeliensis also showed significant algicidal activities within six days.

Environmental Impact Analysis of Acidification and Eutrophication Due to Emissions from the Production of Concrete

Concrete is a major material used in the construction industry that emits a large amount of substances with environmental impacts during its life cycle. Accordingly, technologies for the reduction in and assessment of the environmental impact of concrete from the perspective of a life cycle assessment (LCA) must be developed. At present, the studies on LCA in relation to greenhouse gas emission from concrete are being carried out globally as a countermeasure against climate change. However, the studies on the impact of the substances emitted in the concrete production process on acidification and eutrophication are insufficient. As such, assessing only a single category of environmental impact may cause a misunderstanding about the environmental friendliness of concrete. The substances emitted in the concrete production process have an impact not only on global warming but also on acidification and eutrophication. Acidification and eutrophication are the main causes of air pollution, forest destruction, red tide phenomena, and deterioration of reinforced concrete structures. For this reason, the main substances among those emitted in the concrete production process that have an impact on acidification and eutrophication were deduced. In addition, an LCA technique through which to determine the major emissions from concrete was proposed and a case analysis was carried out. The substances among those emitted in the concrete production process that are related to eutrophication were deduced to be NOx, NH3, NH4+, COD, NO3−, and PO43−. The substances among those emitted in the concrete production process that are related to acidification, were found to be NOx, SO2, H2S, and H2SO4. The materials and energy sources among those input into the concrete production process, which have the biggest impact on acidification and eutrophication, were found to be coarse aggregate and fine aggregate.

Neurotoxicology of Red Tide Poisoning

Red Tide poisoning is a result of toxins released from marine dinoflagellates (various algae) and received its name from the discolored (reddish) water created by an algal bloom. It appears this event has occurred for centuries in many locations even before the occurrence of pollution, agricultural run-off and current observations of global warming. There were reports of the Red Tide in Florida during the 1800’s [1, 2]. However, historical reports indicate that the Red Tide occurred throughout history with an observation noted as early as 1528 in the Gulf of Mexico; although, the first “verifiable” event was in 1648 [2, 3]. The Red Tide occurs throughout tropical waters of the world [4]. In the United States the predominant region is Florida, mostly in the Gulf of Mexico; but events have been noted in the Atlantic and Pacific Oceans. Periodically, there have also been occurrences off the Texas coast [2]. Other locations of notable interest where events occur include Scotland and the South Pacific (e.g. Australia), indicating harmful algal events can occur in northern locations and are likely experiencing an expanding geography due to global warming. There is an increasing frequency of Red Tide phenomena throughout the world with temperature and pollution being indicated as the contributing factors [2].

Water pollution and habitat degradation in the Gulf of Thailand

The Gulf of Thailand has been a major marine resource for Thai people for a long time. However, recent industrialization and community development have exerted considerable stress on the marine environments and provoked habitat degradation. The following pollution problems in the Gulf have been prioritized and are discussed in details: (1) Untreated municipal and industrial waste water are considered to be the most serious problems of the country due to limited waste water treatment facilities in the area. (2) Eutrophication is an emerging problem in the gulf of Thailand. Fortunately, the major species of phytoplankton that have been reported as the cause of red tide phenomena were non-toxic species such as Noctiluca sp. and Trichodesmium sp. (3) Few problems have been documented from trace metals contamination in the Gulf of Thailand and public health threat from seafood contamination does not appear to be significant yet. (4) Petroleum hydrocarbon residue contamination is not a problem, although a few spills from small oil tankers have been recorded. A rapid decrease in mangrove forest, coral reefs, and fisheries resources due to mismanagement is also discussed.

AN INVESTIGATION OF WATER EXCHANGE AND WATER QUALITY MANAGEMENT METHODS USING NATURAL POWER IN OHFUNATO BAY

It is often considered that water quality becomes worse after the construction of port structures; however, port structures may contribute to water purification. This paper describes water quality processes in ports using Ohfunato Bay as an example. In Ohfunato bay, the bottom layer becomes anoxic in summer, due to the formation of a thermocline. In this investigation, it was found that the bottom water inside the bay was carried outside on the ebb tide, depending on the strength of the thermocline. Numerical simulations using a two-layer model confirmed that internal waves carry bottom waters from the bay. Finally, mention is made about water quality management methods using this mechanism. Upwelling of bottom nutrients is prevented by the thermocline, thereby repressing red tide phenomena.

The abundance cycle and influence factors on red tide phenomena of Noctiluca scintillans (Dinophyceae) in Dapeng Bay, the South China Sea

The abundance cycle and influence factors on red tide phenomena of <i>Noctiluca scintillans</i> (Dinophyceae) in Dapeng Bay, the South China Sea

Red tide phenomena in Brunei Darussalam ? some implications for fisheries

Since the first recorded occurrence in 1976, the coastal waters of Brunei Darussalam have been sporadically subjected to the effects of red tide. The 1976 incident overwhelmed the nation which had no previous experience of red tides. Subsequently, a routine was established to monitor the red tide phenomenon. This included plankton monitoring and shellfish toxicity testing, measures which helped to prevent or mitigate adverse human impacts and economic losses to the fishing industry.

A new spectrofluorometric method for the determination of chlorophylls and degradation products and its application in two frontal areas of the Argentine Sea

An improved spectrofluorometric method for the determination of chlorophylls a, b, c and chlorophyll a degradation products was developed. A simple hexane-aqueous acetone partition was employed to separate phytolated from non-phytolated porphyrins. The spectrofluorometric measurement of those phases allows the calculation of the concentration of chlorophylls a, b and c, phaeophytin a, phaeophorbide a and chlorophyllide a. A comparison between the new method and those commonly used on phytoplankton cultures showed that for fresh cultures, without degradation products, chlorophyll concentrations agreed with those of the reference method ( Jeffrey and Humphrey, 1975 , Biochemical Physiological Pflanzen, 167, 191–194). When accessory chlorophylls and degradation products are present, the new method allowed calculations of the concentrations of each of the mixture components, which cannot be determined by routine methods. The spatial distribution of chlorophylls a, b and c and chlorophyll a degradation products in two frontal areas of the Argentine Sea was studied. The tidal frontal system of the Peninsula Valdés has been hydrographically associated with the development of red tide phenomena. The distribution of the photosynthetic pigments along a transect through this typical front structure was studied during a bloom of the dinoflagellate Prorocentrum micans, in January 1986. Results from a transect in the Buenos Aires province shelf cross a shelf-break front showed an autumn bloom of diatoms. Variations in the proportions of the different pigments are discussed in relation to the predominant phytoplankton communities.

Long-term studies on Noctiluca scintillans in the German Bight population dynamics and red tide phenomena 1968–1988

The seasonal development of Noctiluca scintillans has been studied by continuous monitoring at Helgoland-Roads over a period of 20 years. These long-term studies have revealed a temporal distribution pattern of seasonal periodicity with maximal abundances in June/July, and with a low but pronounced peak in December/January. Additionally, over a 21-year term a periodicity of high abundances in three years intervals is observed. In Helgoland waters the mean near surface abundances are higher than the near sea bed values. Apart from physico-chemical influences, buoyancy in Noctiluca is also controlled by its nutritional status. Since 1981, investigations have been extended to the German Bight. Potential centres of Noctiluca growth are found within certain areas near the east-frisian Wadden Sea, persisting from April/May until late July when the centres of high cell concentrations are separated from the coastline. Simultaneously, there is a strong tendency for vertical separation, generating the well-known red-tide phenomena with large mass aggregations at the sea surface, often misleadingly called Noctiluca-blooms, although the cell masses are irreversibly damaged and die off very rapidly. The spatial distribution of Noctiluca as determined every year in July, serves as a realistic base for biomass calculations. From 1981 to 1988 the total per season produced biomass (ashfree dry-weight) of Noctiluca ranges between 30000 (1981) and 69000 tons (1982).

Encystment and excystment of Gonyaulax polyedra during a red tide

As part of long term research program on red tide phenomena in the Kaštela Bay (Adriatic Sea), the formation of temporary cysts of Gonyaulax polyedra Stein was investigated. These cysts formed only when ambient conditions changed dramatically (O 2 depletion, pH decrease), coinciding in time with the occurrence of mass mortalities of marine fauna. The data suggest that temporary cysts act as a protective mechanism for this organism, which, by reducing its metabolic activity, is able to survive in a latent state during unfavourable conditions. It appears, that this mechanism is important in relation to the persistence and recurrence of red tides in this area throughout the summer.