胶州湾东北部养殖海域夏季营养盐分布特征及其对浮游植物生长的影响

以2000年夏季胶州湾东北部养殖海域(女姑山)的现场调查为基础,结合前3年的调查结果和相关的历史资料,对该海域夏季营养盐含量分布特征及其对浮游植物生长的可能限制因子进行了分析和探讨。研究结果表明,胶州湾东北部典型养殖海域夏季表层水体各种营养盐含量高于胶州湾全湾夏季及全年的平均值,铵氮是总溶解态无机氮的主要组成形态,硝态氮次之。该海域的环境因素适宜浮游植物的生长,相关分析显示:叶绿素a与pH及DO呈显著正相关,与PO4、SiO3、NH4、DIN呈负相关。通过分析营养盐对浮游植物生长的限制因素发现,该海域各种营养盐含量相对较高,无机氮不会成为浮游植物生长的限制因素,磷酸盐有限制的可能性,而浮游植物生长受控于硅酸盐的几率最大。

NUTRIENT EFFECT ON PHYTOPLANKTON IN TYPICAL MARICULTURE WATERS IN SUMMER IN THE NORTHEAST OF THE JIAOZHOU BAY

A field investigation in typical mariculture waters in the northeast of the Jiaozhou Bay was con-ducted in summer 2000;nutrient characteristics and the role of limitation to phytoplankton growth were studied in comparison with previous and historical information. The results show that the average nutrients concentrations in surface water were higher than those of overall average of the Jiaozhou Bay in summer and whole year. In our case,ammonium was the dominant composition of DIN in the northeastern part and overall Jiaozhou Bay;and nitrate was the second one. Conditions of temperature,salinity,nutrients concentrations in the area seemed suit-able for phytoplankton growth. In 2000 summer,Chl.a content was positively correlated to those of pH and DO but PO4,SiO3,NH4 and DIN because almost all nutrients concentrations decreased obviously as the result of phytoplankton consumption. In addition,possible nutrient limitation to the phytoplankton growth was analyzed. The results display that the phytoplankton growth in the investigation waters was not limited by DIN. Phosphate probably limited the growth. Silicate,however,certainly limited the phytoplankton growth.