【摘要】 依据2007年4月和8月在乐清湾28°05′~28°35′N、121°00′~121°20′E海域进行海洋综合调查,对乐清湾营养水平指标(E)和有机污染指数(A)值的空间分布特征进行研究,讨论这些分布特征与营养盐、潮流场、污染源和叶绿素之间的联系。结果表明,乐清湾E值和A值分布趋势基本相同,都是由内湾向外湾数量逐渐减少。相关分析表明:溶解态磷酸盐(D IP)和溶解态无机氮(D IN)与E值、A值之间都有密切的相关关系(P=0.000 0),因而是污染乐清湾水体的主要因子。营养盐分布特征的形成,主要由乐清湾地形、潮流、污染源和叶绿素特征决定的,在乐清湾海域,沿外湾东部的海槽是乐清湾中湾和外湾涨落潮的主要路径,形成外湾较低的D IP和D IN值。而养殖污染带来总氮和总磷的数量分别接近和超过50%,因而是乐清湾水体变劣的重要外源性污染物,其次是生活污水和化肥的输入。夏季,浮游植物对营养盐大量利用,有效地减少了乐清湾营养盐的含量,进一步导致水体营养水平指标(E)和有机污染指数(A)值的降低。4月乐清湾水体处于富营养化、严重污染和亚健康状态。8月,内湾和中湾属于污染海域,处于亚健康状态。外湾大部分属于较清洁海域,处于健康状态。更多还原

【Abstract】 Based on the data from an oceanographic census at the Yueqing Bay(28°05′-28°35′N,121°00′-121°20′E) in April and August of 2007,this paper discussed the distribution of eutrophication index(value E) and organic pollution index(value A) in the waters,then analyzed relationship among the distribution and nutrient salts,tidal current field,pollution sources and chlorophyll.Results showed the similar trend of the distribution between value E and value A,whose concentration all decreased from inner bay to outer bay.There was the linear correlation between value E,value A with dissolved inorganic phosphorus(DIP) and nitrogen(DIN)(P=0.000 0).These tell us that eutrophication in the Yueqing Bay affected by DIP and DIN were determined by the background of topography and geomorphy,the distribution of tidal current field,pollution sources and chlorophyll in the Yueqing Bay.For the waters,marine trough along eastern water of outer bay was main path for flood and neap currents,the latter caused low DIP and DIN value there.Pollution from aquaculture was main reasons for eutrophication because 50% DIP and DIN came from the source,then living pollution water and chemical fertilizer pollution.Low DIP and DIN in August came from the utilization of phytoplankton to the nutrient salts,further decreased the value E and value A.In April,water quality of the Yueqing Bay was defined as eutrophication,heavy pollution and sub-health state,but in August,the water quality was defined as common pollution and sub-health state in inner and middle bays,better clean water quality and health state in outer bay.更多还原