China's State Oceanic Administration published a report on oceanic environment quality in the first half of 2007 on Monday.

The report says that in the first half of this year, "red tide", a common name for a phenomenon known as an algal bloom, occurred less frequently and in less areas than the same period last year. However, the East China Sea is still often rampaged by it.

Most large red tides occurred outside the sea entrance of the Yangtze River, and in central and southern parts of Zhejiang and Fujian provinces.

A total of 44 red tides occurred in the first half of the year, about 32 percent less than the same period last year, while the area accounted for just 3,646 square kilometres, about 77 percent less than last year.

Algaes causing the red tides include harmful ones like karenia mikimotoi, phaeoecystis globosa, Heterosigma akashiwo and non-toxic varieties, such as skeletonema costatum and noctiluca scintillans.

Some red tides are caused by more than two types of such algaes.

(Xinhua News Agency August 28, 2007)