Silicon limitation on primary production and its destiny in Jiaozhou Bay, China V： Silicon deficit.pdf

Chinese Journal of Oceanology and Limnology Vo1．23No．2，P 169—175，2005 Silicon limitation on primary production and its destiny in Jiaozhou Bay,China V：Silicon deficit process术 YANG Dongfang(杨东方) ·朴·卅，GAO Zhenhui SUN Peiyan(孙培艳)”，LIU Shuang(刘霜)什 (高振会)什，WANG Peigang(王培刚)”， (~College ofFishery Science，Shanghai Fisheries University,Shanghai 200090．China) ／~Beihai Monitoring Center,State Oceamc Administration．Qingdao 266033．China) 厂”Institute ofOceanoloKr Chinese Academ3，ofSciences．Qingdao 266071．China Received July 1 3，2004；revision accepted Jan．30，2005 Abstract Silicon is a necessary nutrient for diatoms．silicon uptake in diatom reproduction decreased sea- water silicon content．This paper clarified the characteristics of silicon transferring in the sea，which plays an important role in phytoplankton growth，zooplankton graze and marine ecosystem．Analysis revealed that silicate is supplied by terrestrial sources，through plankton uptake，death，and eventually deposits to the sea botom and cannot difluse upward．This is a general silicon deficit process．M any global marine waters showed the same silicon transfer route：land—silicon biogeochemical process~sea bottom．River flow brings abundant silicate into marine waters．silicate concentration in the waters decreased in the distance away from the river estuaries．In discussion of silicon characteristics and its transfer route．it was considered that the main factor controling the mechanism of diatom and non—diatom red tides occurrence is silicon．and the changes in silicon source．Human activities，such as sea—route cuting by building embankment and dam，and silicon supplement by the sea，such as sandstorm，rainstorm and storm tide，have largely impaired the earth ecosystem and hugely threatened the human existence．It is suggested in this paper that man should resume the original face of the Si input into the sea to keep natural ecosystem in sustainable pattern． Key words：silicon，biogeochemical process，deficit process，global waters