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

1989年，对菲律宾、泰国和文莱达鲁萨兰国爆发的有毒鞭毛藻进行了国际合作研究。1989年，在马辛洛克湾和马尼拉湾里迈沿岸水域进行化学环境研究的同时，开展了对巴哈门火辉藻和有毒贝类分布的调查研究。继续进行夜足单胞菌的分离培养。在七月二十六日至二十七日期间，我们在马辛洛克湾的九个监测站进行了测量。海湾是一个开放的类型，面积为10 X 5公里，从南到北拉长，位于吕松岛的南部西海岸。20米左右水深的底水盐度约为30%。调查期间降水较多，地表水盐度降至20%左右。结果表明，海湾的水质容易受到陆地水流入的影响。在北部的奥永湾，bahamense的细胞密度为40个细胞/ml。沉积物中的囊肿主要分布在中部地区，计数为50个细胞/ml，但在中部和南部地区几乎没有发现营养细胞。Masinloc湾发现的包囊主要是异养种，如Brigantedinium spp., Diplopelta cf. parva和Spiniferites spp.，海水中采集的1.1万个细胞中，bahamense的psp毒性为1 MU。中央区底部笔螺和棘螺的毒力分别为4和20亩/克。他们似乎陶醉在巴哈门斯的囊肿中。这项调查于8月2日至3日在马尼拉湾里迈沿岸进行。马尼拉湾海水盐度为18.49% ~ 22.53%。在地表水中占26.87 - 29.94%。在水底。硝态氮含量为43 ~ 64 muM/l，磷含量为3.4 ~ 4.1 muM/l。这些数值似乎来自于海湾富营养化的过程。本研究首次发现并培养了一种产生PSP的裸鼠。HPLC分析表明，培养的悬藤的PSP主要成分为C1、C2和C4三种毒素。从PSP组成来看，G. catenatum似乎不是马尼拉湾贝类中毒的原因。此外，还分离培养了一种鱼类杀手——查顿菌。在泰国湾，从绿色夜蛾中分离出夜蛾脚单胞菌，并进行了实验室培养。根据N. scinitillans的分析结果发明培养基，将培养基的pH调至4.5，培养温度保持在28^ C。生长稳定期最大细胞密度约为20万个/ml。根据1990年的研究结果，随着贝类中毒的发生，马辛洛克湾和马尼拉湾西部的有毒巴hamense及其囊肿的分布也明显清晰起来。这些项目的进一步研究将有助于制定东南亚赤潮问题的对策，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