Nitrogen and phosphorus budgets of the Changjiang River estuary

IOCAS-IR

	Nitrogen and phosphorus budgets of the Changjiang River estuary
	Li XA(李祥安); Yu ZM(俞志明); Song XX(宋秀贤); Cao XH(曹西华); Yuan YQ(袁涌铨)
发表期刊	Chinese Journal of Oceanology and Limnology
ISSN	0254-4059
	2011-07-15
出版年	2011
卷号	v.29 期号:04 页码:46-58
文献类型	CNKI期刊论文
摘要	Eutrophication has emerged as a key environmental problem in Chinese coastal waters, especially in the Changjiang (Yangtze) River estuary. In this area, large nutrient inputs result in frequent harmful algal blooms and serious hypoxia in bottom waters. Four cruises were made in the estuary in 2006 to assess the concentration and distribution of dissolved inorganic nitrogen (DIN) and phosphorus (DIP). The concentration of DIN decreased gradually in a linear relationship with salinity from the river mouth to outer waters, while DIP was relatively more dispersed. A modified box budget method was used to estimate nutrient fluxes in the estuary and its adjacent waters. Water and nutrient budgets as well as primary production and denitrification rates were estimated from the box budget model. Estimated water residence time in the estuary was about 11 d. The turbid mixing zone released 33% of DIN and 49% of DIP, while in the adjacent outer sea 17.9 mmol DIN/m2·d and 0.36 mmol DIP/m2·d were fixed. Dissolved inorganic phosphorus was imported from the deep open sea waters, supporting primary production and population growth in this zone. Net ecosystem production (NEP) was calculated at 38.2 mmol/m2·d in the outer estuary and the estimated rate (N-fixation minus denitrification) was negative (1.92 mmol/m2·d), implying that a large amount of input nitrogen was taken up by algae and recycled through denitrification in bottom water and sediment.
关键词	nitrogen phosphorus nutrients transport budget model Changjiang (Yangtze) River estuary
CNKI专辑号	A;B;
CNKI专辑名称	基础科学;工程科技Ⅰ辑;
CNKI专题号	B027;
CNKI专题名称	环境科学与资源利用;
分类号	X13
收录类别	中科院核心
语种	英文;
资助项目(基金）	Supported by the National Basic Research Program of China (973 Program) (No. 2010CB428706) ; the National Natural Science Foundation of China for Creative Research Groups (No. 40821004) ; the National High Technology Research and Development Program of China (863 Program) (No. 2008AA09Z107)
文献类型	CNKI期刊论文
条目标识符	http://ir.qdio.ac.cn/handle/337002/191643
专题	中国科学院海洋研究所
作者单位	1.KeyLaboratoryofMarineEcologyandEnvironmentalScience,InstituteofOceanology,ChineseAcademyofSciences 2.GraduateUniversityofChineseAcademyofSciences
推荐引用方式 GB/T 7714	Li XA,Yu ZM,Song XX,et al. Nitrogen and phosphorus budgets of the Changjiang River estuary. 2011.