Physical-biological coupling in the Pearl River Estuary

CORC > 南海海洋研究所 > 中国科学院南海海洋研究所 > 热带海洋环境国家重点实验室(LTO)

	Physical-biological coupling in the Pearl River Estuary
	Harrison, PJ ; Yin, KD ; Lee, JHW ; Gan, JP ; Liu, HB
刊名	CONTINENTAL SHELF RESEARCH
	2008
卷号	28 期号:12 页码:1405-1415
关键词	Pearl River Estuary phosphorus limitation chlorophyll eutrophication algal blooms sewage
ISSN号	0278-4343
通讯作者	harrison@ust.hk
中文摘要	The Pearl River Estuary is a subtropical estuary and the second largest in China based on discharge volume from the Pearl River. Processes in the estuary vary spatially and temporally (wet vs dry season). In the dry season at the head of the estuary, hypoxic and nearly anoxic conditions occur and NH4 reaches > 600 mu M, NO3 is similar to 300 mu M and nitrite is similar to 60 mu M indicating that nitrification and denitrification may be important dry season processes in the region extending 40 km upstream of the Humen outlet. There are very few biological studies conducted in this upper section of the estuary in either the dry or wet seasons and hence there is a need for further research in this region of the river. In the wet season, the salinity wedge extends to the Hongqimen outlet and oxygen is low (35-80% saturation). Nitrate is similar to 100 mu M, silicate similar to 140 mu M: and phosphate is relatively low at similar to 0.5 mu M, yielding an N:P ratio up to similar to 200:1 in summer. Nutrients decrease in the lower estuary and primary productivity may become potentially P-limited. Eutrophication is not as severe as one would expect from the nutrient inputs from the Pearl River and from Hong Kong's sewage discharge. This estuary shows a remarkable capacity to cope with excessive nutrients. Physical processes such as river discharge, tidal flushing, turbulent dispersion, wind-induced mixing, and estuarine circulation play an important role in controlling the production and accumulation of algal blooms and the potential occurrence of hypoxia. Superimposed on the physical processes of the estuary are the chemical and biological processes involved in the production of the bloom. For example, the 100N:1P ratio indicates that P potentially limits the amount of algal biomass (and potential biological oxygen demand) in summer. While extended periods of hypoxia are rare in Hong Kong waters, episodic events have been reported to occur during late summer due to factors such as low wind, high rainfall and river discharge which result in strong density stratification that significantly dampens vertical mixing processes. Nutrient loads are likely to change over the next several decades and monitoring programs are essential to detect the response of the ecosystem due to the future changes in nutrient loading and the ratio of nutrients. (c) 2008 Elsevier Ltd. All rights reserved.
学科主题	Oceanography
收录类别	SCI
原文出处	40739
WOS记录号	WOS:000257620200002
公开日期	2011-07-03
内容类型	期刊论文
源URL	[http://ir.scsio.ac.cn/handle/344004/5989]
专题	南海海洋研究所_热带海洋环境国家重点实验室(LTO)
推荐引用方式 GB/T 7714	Harrison, PJ,Yin, KD,Lee, JHW,et al. Physical-biological coupling in the Pearl River Estuary[J]. CONTINENTAL SHELF RESEARCH,2008,28(12):1405-1415.
APA	Harrison, PJ,Yin, KD,Lee, JHW,Gan, JP,&Liu, HB.(2008).Physical-biological coupling in the Pearl River Estuary.CONTINENTAL SHELF RESEARCH,28(12),1405-1415.
MLA	Harrison, PJ,et al."Physical-biological coupling in the Pearl River Estuary".CONTINENTAL SHELF RESEARCH 28.12(2008):1405-1415.