Flushing rate and salinity may control the blooms of the toxic dinoflagellate Alexandrium tamarense in a river/estuary in Osaka Bay, Japan

Yamamoto, Kazuo; Tsujimura, Hirotaka; Nakajima, Masaki; Harrison, Paul J.

doi:10.1007/s10872-013-0203-7

Cited by 22 publications

(5 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In Harima-Nada and Osaka Bay, there have been two significant long-term environmental changes, i.e. an increase in water temperature and a decrease in the nutrient concentrations (Nishikawa et al 2010, 2014, Yamamoto 2019. Nishikawa et al (2010) indicated that there was a significant increase in the lowest winter monthly temperature of 0.042°C during the 35-year period .…”

Section: Discussionmentioning

confidence: 99%

Temporal variations in the copepod community structure during the sand lance fishery season near the Akashi Strait, eastern Seto Inland Sea

Nishikawa,

Watanabe,

Furusawa

et al. 2024

Plankton Benthos Res

View full text Add to dashboard Cite

Around the Akashi Strait, about half of the catch of the sand lance in Harima-Nada and Osaka Bay is caught in winter to early spring. The annual catch has continued to decrease after the 1990s, and it is suggested that the decline in catch was caused by copepod shortage as food. In the present study, frequent samplings of copepods were conducted from December to early April around the Akashi Strait for three years to evaluate copepod abundance and biomass. Around the Akashi Strait, the dominant species by abundance were Paracalanus spp., Oithona spp. and Microsetella norvegica, but by biomass, the most dominant was Calanus sinicus. Cluster analysis showed that copepod adult communities, based on biomass, were classified into five groups, and the representative species were Oithona similis, Subeucalanus crassus, M. norvegica, Euchaeta plana and C. sinicus, respectively. Especially from February to early April, most of the copepod communities were classified into cluster group 5, characterized by a high biomass of C. sinicus. This period coincides with the active feeding on copepods by sand lance. These results suggest that C. sinicus is the most important prey item for sand lance around the Akashi Strait. In addition, the temporal recruitment of pelagic species such as S. crassus and E. plana contributed to an increase in copepod biomass. There is concern that environmental shifts will lead to declines in C. sinicus, resulting in a decline in the total copepod biomass in this area.

show abstract

Section: Discussionmentioning

confidence: 99%

Temporal variations in the copepod community structure during the sand lance fishery season near the Akashi Strait, eastern Seto Inland Sea

Nishikawa,

Watanabe,

Furusawa

et al. 2024

Plankton Benthos Res

View full text Add to dashboard Cite

show abstract

“…2), with an apparent increasing trend since 1994 (Yamamoto et al 2017). A high-density red tide of 72,400 cells mL −1 occurred in April 2007 at the Sakai Dejima Fishing Port in Osaka Prefecture, and another of 14,000 cells mL −1 was confirmed in Yodo River (Yamamoto et al 2009a(Yamamoto et al , 2011(Yamamoto et al , 2013. These events revealed that A. catenella (group I) not only causes toxification of bivalve mollusks by PSP toxins with low cell densities, but if conditions are suitable, this species can cause red tides and kill various forms of marine life (Yamamoto et al 2009a).…”

Section: Toxic Bloomsmentioning

confidence: 98%

Harmful algal blooms and environmentally friendly control strategies in Japan

2021

Self Cite

View full text Add to dashboard Cite

The presence and status of harmful algal blooms (HABs) in Japan are reviewed, revealing a decrease in red tides; however, toxic blooms are found to be increasing in western Japan. Environmentally friendly control strategies against HABs are also compared with integrated agricultural pest management. Very high densities (105–108 CFU/g) of algicidal and growth-inhibiting bacteria were found in biofilm on seagrass and seaweed surfaces and in surrounding coastal seawater. The situation in freshwater ecosystems is similar to coastal seas for toxic cyanobacterium, Microcystis aeruginosa, and aquatic plants. These findings offer new insights into the ecology of influential bacteria and harmful algae, suggesting that protection and restoration of native seagrasses and seaweeds in coastal marine environments should be implemented to suppress HABs. Diatom blooms were successfully induced with bottom sediment perturbation to prevent the occurrence of harmful flagellates such as Chattonella spp. and Alexandrium catenella in the Seto Inland Sea; however, this method requires robust and reproducible verification. “Sato-Umi” is a helpful concept for HAB control in the sea and freshwater ecosystems when adequately managed by people (e.g., appropriate bottom perturbation; protection and restoration of seaweeds, seagrasses, and aquatic plants; application of polycultures of fish, seaweeds, etc.).

show abstract

“…In the Yodo River estuary of Osaka Bay, the salinity was played as an environmental factor controlled the abundance of Alexandrium tamarense. The population of A. tamarense was the most abundant when salinities were relatively higher than 15 psu, river discharge was low, and the water column was stable (Yamamoto et al 2013).…”

Section: Phytoplankton Distributionmentioning

confidence: 99%

Phytoplankton distribution in Mikawa Bay of Japan in relation to environmental factor

Djumanto

2017

Bonorowo Wetlands

View full text Add to dashboard Cite

Abstract. Djumanto, Rasul E, InoueT, Aoki S. 2017. Phytoplankton distribution in Mikawa Bay of Japan in relation to . Species composition and horizontal distribution of phytoplankton in relation to temperature and salinity variables were investigated in Mikawa Bay of Japan. Surface seawater was filtered with a 30 cm diameter conical plankton net with a mesh size of 53 µm weekly from mid-August to late September 2011. Surface layer temperature and salinity were measured with a CTD sensor. Phytoplankton samples were observed with an inverted microscope with phase contrast at 100-400 magnification. The salinity and surface temperature data, as well as the density of the phytoplankton horizontally, were made contour maps by connecting the location of each sampling station having the same value. Contour maps were created using surfer software.The result showed that the average of temperature at the 1 m surface layer was ranged from 22.7 to 28.7 o C. Meanwhile, salinity was ranged from 11.8 psu to 30.0 psu. Phytoplankton was abundant in the area with the high temperature and low salinity. The most abundant species among station of sampling in Bacillariophyceae was Chaetoceros sp(p). (52.2%) followed by Pseudo-Nitzschia sp(p) (27,7%), and then Coscinodiscus sp(p). (6.3%). On the other hand, the most abundant in Dinophyceae was Dinophysis sp(p). (1.1%) followed by Ceratium fusus (0.9%), and then Ceratium furca (0.8%) which was mostly dominant in off river mouth area. The density center and contour lines of phytoplankton population were changed and moved depending on salinity or temperature profiles.

show abstract

Flushing rate and salinity may control the blooms of the toxic dinoflagellate Alexandrium tamarense in a river/estuary in Osaka Bay, Japan

Cited by 22 publications

References 13 publications

Temporal variations in the copepod community structure during the sand lance fishery season near the Akashi Strait, eastern Seto Inland Sea

Temporal variations in the copepod community structure during the sand lance fishery season near the Akashi Strait, eastern Seto Inland Sea

Harmful algal blooms and environmentally friendly control strategies in Japan

Phytoplankton distribution in Mikawa Bay of Japan in relation to environmental factor

Contact Info

Product

Resources

About