摘要
受防波堤建设影响,半封闭式港湾往往出现水体交换不畅,自净能力较弱的现象,为研究防波堤不同型式对湾内水动力环境的影响,以珠江河口典型的半封闭式港湾香洲渔港为例,计算分析全闭合式防波堤、不同开口宽度(20、40、60、100 m)的防波堤布置方案下,湾内水体交换条件及污染物输移扩散规律的差异。结果表明:与全闭合式防波堤方案相比,在设置20、40、60、100 m的开口宽度方案下,湾内水体半交换周期分别提高5.0、11.0、14.0、14.5 h。开口40 m以上的方案对水动力改善效果明显优于开口20 m的方案,但开口40、60、100 m的3个方案效果并无明显差异。考虑区域污染源输入的影响,防波堤开口设置方案下,开口附近水域的无机氮浓度增加0.2~0.4 mg/L,将进一步加剧湾内北部区域的无机氮污染压力,而南部区域水环境质量则因湾内水体交换能力加强而有所改善。
Affected by breakwater construction,the water exchange of semi-closed harbor is often not smooth,and the self-purification ability is weak.To study the influence of different types of breakwater on the hydrodynamic environment in semi-closed harbor,the article took a typical semi-enclosed port in the Pearl River estuary,Xiangzhou fishing port as an example to analyze the differences of water exchange ability and the transport law of pollutants under the layout scheme of breakwater with opening width including 20、40、60、100 m.The results showed that,compared with the fully closed breakwater scheme,under the scheme of opening width of 20、40、60、100 m,the half exchange period of water in the harbor increased by 5.0 hours,11.0 hours,14.0 hours and 14.5 hours.The scheme with opening more than 40m was better than 20 m.However,there was no significant difference in the effect of the three schemes of opening 40、60、100 m.Considering the influence of regional pollution source input,under the scheme of breakwater opening,the concentration of inorganic nitrogen increased by 0.2~0.4 mg/L in the area near the opening.It further aggravated the pressure of inorganic nitrogen pollution in the northern part of the harbor,while the quality of water environment in the southern part of the harbor was improved due to the enhancement of water exchange ability.
作者
吴琼
李木桂
罗欢
WU Qiong;LI Mugui;LUO Huan(Pearl River Water Resources Research Institute,Guangzhou 510611,China;Guangdong Provincial Engineering Technology Research Center for Life and Health of River&Lake,Guangzhou 510611,China)
出处
《人民珠江》
2021年第12期96-105,共10页
Pearl River
基金
国家自然科学基金项目(51809298)
广东省重点领域研发计划项目(2019B110205004)。
关键词
半封闭式港湾
防波堤
水体交换
污染物输移扩散
semi-closed harbor
breakwater
water exchange
transport and diffusion of pollutants
