杭州湾营养盐时空分布特征及其影响研究

Temporal-Spatial Distribution and Influencing Factors of Nutrients in the Hangzhou Bay

文章基于2015年1—12月杭州湾海域12个航次的调查资料,对杭州湾海域营养盐溶解无机氮(DIN)和活性磷酸盐(PO_4^(3-))的月度时空分布特征及其影响进行了探讨。结果表明,杭州湾表层海水DIN和PO_4^(3-)含量空间分布月际间变化明显,其变化受湾内、沿岸径流输入和长江冲淡水影响显著。杭州湾海域12个月DIN含量均超第四类海水水质标准,硝酸盐氮(NO_3^-)占DIN的94%及以上。N/P值处于较高水平,内湾(IB)和外湾(OB)的N/P值季节性变化幅度比中湾(CB)大,海湾生态系统对磷的变化敏感。营养盐-盐度对研究区域的水体混合状况有明显的指示作用,杭州湾营养盐的分布主要受物理混合作用所控制,浮游生物活动对营养盐分布的影响相对较小。

Based on the 12 investigations carried out in the Hangzhou Bay from January toDecem bet 2015 ,spatial and temporal distribution and influencing factors of dissolved inorganic nitrogen （DIN） and phosphate （PO43- ） in the Hangzhou Bay were discussed.The results showed that dis tributions and variations of DIN and PO43- were significant by months,which were related to in shore runoff in the bay and the Changjiang River diluted water. DIN content of the 12 months were all over the fourth class of seawater quality standard.Nitrate （NO3） accounted for approx mate 94% of DIN in the Hangzhou Bay.Generally the N/P rations of the 12 investigations were in high value, indicatin seasonal changes of g N that the bay ecosystem is sensitive to the change of phosphorus content.The bay （CB）.Nutrient sa /p lini n inner bay （IB） and outer bay （OB） were higher than that in center ty plays an obvious role in indication the water mixing process in thestudy area.The distributions of nutrient were mainly controlled by physical mixing of water and plankton activity was relatively insignificant in this area.