2010-2011年胶州湾叶绿素a与环境因子的时空变化特征

Temporal and spatial variations of chlorophyll aand environmental factors in Jiaozhou Bay in 2010-2011

2010年4、6、8、10月和2011年1、3月在胶州湾开展了6个航次的综合调查,研究了表层海水温度、盐度、营养盐和叶绿素a浓度的时空变化特征。调查期间,总无机氮(DIN)、磷酸盐(PO4)和硅酸盐(SiO3)多呈现东北部湾边缘高,而湾内和湾口低的空间分布特征。季节变化表明,DIN和PO4主要受养殖排放、河流径流输入和浮游植物生长消耗的影响,呈现初夏和秋季高,夏末和冬季低的特点;而SiO3主要受河流径流输入和浮游植物消耗的影响,呈现夏、秋高,而冬、春低的特点。营养盐浓度和结构分析表明,胶州湾存在PO4和SiO3的绝对和相对限制;SiO3限制尤其严重,是控制胶州湾浮游植物生长的主要环境因子。SiO3和PO4的限制主要表现在冬季,几乎遍布整个海湾;夏季降水可有效缓解海域的SiO3限制。叶绿素a浓度呈现春、夏季高,秋、冬季低的季节分布,温度、营养盐浓度与结构和季节性贝类养殖活动是控制胶州湾叶绿素a浓度时空分布的关键因素。

Temporal and spatial variations of surface seawater temperature（SST）,salinity（SSS）,nutrient concentrations and chlorophyll aconcentrations were studied in April,June,August and October 2010 and January and March 2011 in Jiaozhou Bay.Spatial distributions showed that dissolved inorganic nitrogen（DIN）,phosphate（PO4）and silicate（SiO3）concentrations were higher in the northeast edge and decreased gradually towards the inner and the mouth of Jiaozhou Bay during most time of study.DIN and PO4 were relatively higher in early summer and autumn but lower in winter and late summer as a result of the effects from aquaculture,exogenous nutrients input and phytoplankton consumption.SiO3 concentrations were mainly affected by phytoplankton consumption and river loadings and were higher in summer and autumn and lower in spring and winter.The analysis on concentrations and structures of nutrients of Jiaozhou Bay during the study period indicated that PO4 and SiO3 were both absolute and relative limitations,and SiO3 limitation was more serious and acted as the important factor which controlled the growth of phytoplankton all over the year.The most serious limitation of SiO3 and PO4occurred in winter and was found in the whole bay.The nutrient loadings as a result of rainfall in summer,however,relieved SiO3 limitation.The chlorophyll aconcentrations were higher in spring and summer and lower in autumn and winter.Temperature,nutrients and the ingestion of filter mussels were the dominant effect factors of the concentrations and distribution of chlorophyll a.