基于改进模型的辽东湾东岸营口海域海底地下水排泄量计算  

Calculating Submarine Groundwater Discharge in the East Coast of Liaodong Bay Based on the Improved Radium Mass Balance Model

作　　者：郭巧娜[1] 李孟军 赵岳 窦智[1] 周志芳[1] GUO Qiao-na;LI Meng-jun;ZHAO Yue;DOU Zhi;ZHOU Zhi-fang(School of Earth Sciences and Engineering,Hohai University,Nanjing 210000,China)

机构地区：[1]河海大学地球科学与工程学院,南京210000

出　　处：《长江科学院院报》2022年第10期8-15,23,共9页Journal of Changjiang River Scientific Research Institute

基　　金：国家自然科学基金面上项目(41772235);中央高校基本科研业务费项目(B210202108)。

摘　　要：海底地下水排泄(SGD)是全球水循环的重要组成部分,也是向海洋输送营养盐等各类化学物质的必要途径之一。以辽东湾东部营口海域为研究对象,以天然镭同位素(Ra、Ra)作为示踪剂,建立镭质量平衡模型并加以改进,进而探讨再循环海水(RSGD)对研究区内水体刷新时间、SGD及携带氮磷营养盐通量的影响程度。结果表明:利用镭质量平衡模型计算水体刷新时间为9 d,改进后的镭质量平衡模型计算出的水体刷新时间为14.35~18.11 d;传统模型下SGD通量为(3.01~3.51)×10^(8)m^(3)/d。改进模型评估的SGD通量为(3.55~4.39)×10^(8)m^(3)/d,改进模型评估的水体刷新时间与SGD均明显高于初始模型,其中水体刷新时间增加了59.44%~101.22%;SGD通量增加了17.94%~25.07%。在此基础上,地下水向海输入的氮、磷营养盐通量在考虑RSGD的情况下分别为1.73×10^(8)、1.52×10mol/d。研究结果证明了RSGD对SGD和营养盐通量存在较大影响,为营口海域生态环境评估提供了基础数据。Submarine groundwater discharge(SGD)represents an essential part of the global water cycle and one of the vital ways to transport various chemical substances such as nutrients to the ocean.The influences of recirculated seawater(RSGD)on water body refresh time,SGD,and the flux of nitrogen and phosphorus nutrients in Yingkou sea area in the eastern part of Liaodong Bay were investigated by establishing and improving the radium mass balance model with natural radium isotopes(Ra andRa)as tracers.The water refresh time calculated by the radium mass balance model is 9 days while by the improved radium mass balance model 14.35-18.11 days.The SGD flux in the traditional model is(3.01-3.51)×10^(8)m^(3)/d while in the improved model(3.55-4.39)×10^(8)m^(3)/d.The water refresh time and SGD calculated by the improved model increased by 59.44%-101.22%and 17.94%-25.07%,respectively,compared with those by the traditional model.Moreover,the nitrogen and phosphorus nutrient fluxes from groundwater to the sea are 1.73×10^(8)mol/d and 1.52×10^(9)mol/d,respectively,in consideration of RSGD.In conclusion,RSGD has a remarkable impact on SGD and nutrient fluxes.

关 键 词：海底地下水排泄 镭同位素 改进镭质量平衡模型 氮磷营养盐 营口海域 

分 类 号：P641.2[天文地球—地质矿产勘探]