涨落潮过程对闽江下游感潮河段表层水体氮和磷及其赋存形态的影响  

The changes of nitrogen and phosphorus contents and their occurrence forms in surface water as affected by flood tide and ebb tide in the tidal reach of the Minjiang River

作　　者：陈瑶 朱贵青[1,2] 林晓皓 吴福忠 CHEN Yao;ZHU Guiqing;LIN Xiaohao;WU Fuzhong(School of Geographical Sciences,School of Carbon Neutrality Future Technology,Fujian Normal University,Fuzhou 350007;Key Laboratory for Humid Subtropical Eco-geographical Processes of the Ministry of Education,Institute of Geography,Fujian Normal University,Fuzhou 350007)

机构地区：[1]福建师范大学地理科学学院,碳中和未来技术学院,福州350007 [2]福建师范大学地理研究所,湿润亚热带生态-地理过程教育部重点实验室,福州350007

出　　处：《环境科学学报》2024年第1期516-525,共10页Acta Scientiae Circumstantiae

基　　金：国家自然科学基金项目(No.32171641)。

摘　　要：以闽江下游感潮河段(117 km)为研究对象,在巨潮日随着涨潮(从入海口沿江而上)和落潮(从上游顺流而下)的过程,采集11个样点的表层水样,分析水体中氮和磷含量及其赋存形态与环境因子之间的相关性.结果表明,相对于落潮,涨潮显著增加了上河段23.2%的溶解性总氮、19.7%溶解性无机氮和16.4%的硝态氮含量,但降低了全河段54%的铵态氮含量.同时,涨潮显著增加了上河段48.8%的溶解性总磷和1.2倍溶解性有机磷的含量,但降低了全河段29.6%正磷酸盐的含量.综合分析表明,涨落潮过程通过顶托作用、水动力扰动和稀释过程,改变盐度等水环境条件,影响表层水体的氮、磷含量及其转化过程.相对于落潮,涨潮过程会减弱不同形态的氮、磷含量及其比值与盐度、pH、温度和悬浮物含量的相关关系.这些结果对深入认识涨落潮过程对闽江下游感潮河段氮、磷迁移转化的影响机制,以及入海河流生态系统管理具有一定的科学意义.The lower reach of the Minjiang River(117 km)was selected with obvious tide-sensing effect,and surface water samples from 11 sites were collected during the process of high tide(upstream from the estuary)and low tide(downstream from the upper reaches)on giant tide days.We analyzed the contents of nitrogen and phosphorus in surface water and their occurrence forms,and checked the relationships with environmental factors.Compared with ebb tide,flood tide significantly increased the contents of dissolved total nitrogen,dissolved inorganic nitrogen and nitrate nitrogen by 23.2%,19.7%and 16.4%in the upper tidal reach,but decreased the ammonium nitrogen by 54%in the whole reach.Moreover,the flood tide significantly increased the contents of dissolved total phosphorus and dissolved organophosphates by 48.8%and 1.2 times in the upper reaches,but decreased the contents of orthophosphates by 29.6%in the whole reach.Comprehensive analysis showed that the process of flood tide and ebb tide could change the water environment conditions such as salinity through tide lifting,hydrodynamic disturbance and dilution,and then alter the contents of nitrogen and phosphorus and their conversion process in surface water.Compared with the high tide,the ebb tide could weaken the correlation between the contents of nitrogen and phosphorus and their ratios with salinity,pH,temperature and suspended matter content.These results would be of scientific significance for further understanding the mechanisms in the migration and transformation of nitrogen and phosphorus as affected by the flood and ebb tide processes in the lower tidal reach of Minjiang River,and provide some scientific data for the management of seagoing river ecosystem.

关 键 词：感潮河段 氮 磷 涨潮 落潮 空间分布 闽江 

分 类 号：X522[环境科学与工程—环境工程]