Studies on Red Tides Associated with the Eutrophication in Coastal Areas of Western Pacific

1989年在菲律宾、泰国和文莱开展了有毒甲藻暴发的国际合作研究，1989年在马尼拉湾马辛洛克湾和里迈沿岸水域开展了巴哈马甲藻和有毒贝类分布调查和化学环境研究。7月26 - 27日在马辛洛克湾9个站位进行了调查。海湾为开阔型，面积10 X5 Km，南北狭长，位于吕宋岛西南海岸。20 m左右的底层水盐度约为30%。在调查期间，下了大雨，地表水的盐度下降到20%左右。结果表明，该湾的水质容易受到陆地水流入的影响。 ...更多信息 北方沉积物中的孢囊主要分布在中心区，计数为50个/ml，而在中部和南部几乎没有发现营养细胞。在马辛洛克湾发现的孢囊主要是异养种，如Brigantedinium spp。双盾藻属从海水中采集的巴哈马对虾的PSP毒性为1 MU/11，000个细胞。中心区底部的笔形贝和脊椎虫的毒力分别为4和20 μ g/g。8月2 ~ 3日在马尼拉湾里迈沿岸进行了沿着调查，马尼拉湾的盐度为18.49 ~ 22.53%.地表水为26.87 - 29.94%。在水底。硝酸盐氮在43 - 64 μ M/l的高范围内，磷酸盐磷为3.4 - 4.1 μ M/l。本研究首次发现并培养了链裸藻（Gymatinium catenatum），并对培养的链裸藻进行了PSP的HPLC分析。连环藻显示存在C1、C2和C4毒素作为主要成分。从PSP的组成来看，G.链状藻似乎不是马尼拉湾贝类中毒的原因。查顿氏菌，在泰国湾从绿色夜光藻中分离到一株能杀死鱼类的细菌，并在实验室成功培养。根据N.将培养基的pH调节至4.5，培养温度保持在28 ℃。生长稳定期的最大细胞密度约为200，000个细胞/ml。根据1990年获得的结果，随着贝类中毒的发生，有毒的巴哈马对虾及其包囊在马辛洛克湾和马尼拉湾西部的分布情况也变得相当清楚，本项目的进一步研究将有助于制定东南亚PSP问题的对策，并促进赤潮生物的基础研究。少

In 1989 the international cooperative research on the outbreaks of toxic dinoflagellates in Philippines, Thailand and Brunei Darussalum were carried out.In 1989 the studies were developed to survey the distribution of Pyrodinium bahamense and toxic shellfish together with the chemical enveronmental research in Masinloc Bay and the coastal water area of Rimai of Manila Bay. The isolation and culture of Pedinomonas noctilucae were continued.Surveys in Masinloc Bay were carried out at 9 stations on July 26 - 27. The Bay is an open type with the area of 10 X 5 Km, elongated from south to north, which is located in the southern west coast of Luson Island. Salinities of the bottom water of about 20 m depth were about 30%。. It was heavy rain fall through the survey period and the salinities of surface water decreased to around 20 %。. This result shows the water qualities of the Bay are easily affected by the inflow of land water.The cell density of P. bahamense was 40 cells /ml at Oyon Bay in … More the north. The cysts in the sediment mainly distributed in central area and were counted to be 50 cells /ml but the vegetative cells were scarcely found in central and south area. Cysts which were found in Masinloc Bay were mainly heterotrophic species such as Brigantedinium spp. Diplopelta cf. parva and Spiniferites spp.PSP toxicity of P. bahamense collected from sea water was 1 MU in 11,000 cells. The toxicity of penshell and Spondylus sp. In the bottom of central area were 4 and 20 mu/g, respectively. They seemed to be intoxicated by the cysts of P. bahamense.The survey along the coast of Rimai, Manila Bay was carried out on August 2- 3.The salinities of Manila Bay were 18.49 - 22.53 %。 in surface water and 26.87 - 29.94 %。 in bottom water. Nitrate-nitrogen was in the high range of 43 - 64 muM/l and phosphate phosphorus was 3.4 - 4.1 muM/l. These values seemed to derive from proceeding of the eutrophication of the Bay.Gymnodinium catenatum which is a PSP producer was found as the first case of the Bay and cultured.HPLC analysis of PSP of cultured G. catenatum revealed the presence of C1, C2 and C4 toxins as main components. Considering from the PSP composition, G. catenatum seemed not to be responsible to the intoxication of shellfish in Manila Bay. Chattonella sp., a fish killer, was also isolated and cultured.In Gulf of Thailand, Pedinomonas noctilucae was isolated from green Noctiluca and succeeded to the culture in laboratory. The culture medium was invented according to the analytical results of N. scinitillans and pH of the medium was adjusted to 4.5 and culture temperature was maintained at 28^ﾟC. Maximum cell densities in stationary phase of the growth was about 200,000 cells/ml.Based on the results obtained in 1990, the distribution of toxic P. bahamense and its cysts in Masinloc Bay and west of the Manila Bay considerably became clear together with the shellfish toxication.The further studies on this projects will be expected to contribute to establish the countermeasures on PSP problems in south east Asia and also to promote the fundamental studies on red tide organisms. Less