Research on Suspended Materials and Primary Production in Ariake Bay

在过去的30年里，整个有明湾的透明度平均提高了50%。透明度增加的区域与赤潮数量增加的区域相对应。透明度可以用表面无机悬浮物和叶绿素a来定量表示。透明度的增加似乎是由于悬浮物减少了约10 mg L^<-1>引起的。初级产量与光区深度呈线性相关，透明度增加的比例应导致相同比例的初级产量增加。这些结果表明，透明度的增加是有明湾赤潮增加的原因之一。

Transparency increased in the entire Ariake Bay with an average of 50% during the last 30 years. The area with increased transparency corresponded with the area of increased number of red tides. The transparency can be expressed quantitatively in terms of surface inorganic suspended matter and chlorophyll a. The increase of transparency seems to be caused by decrease of about 10 mg L^<-1> of suspended matter. Primary production was linearly correlated with euphotic zone depth, and the ratio of increase of transparency should result increase of same ratio of primary production. These results indicate that the increase of transparency is one of the causes of increase of red tide in Ariake Bay.