南水北调工程对长江口盐水入侵和淡水资源的影响

doi:10.3969/j.issn.1000-5641.201941031

摘要/Abstract

摘要： 南水北调工程为跨流域调水工程，其对于长江口淡水资源变迁的影响是当今研究热点之一. 本文应用三维数学模型，研究南水北调东线和中线工程短期和远期调水方案对长江河口盐水入侵和淡水资源的影响. 结果表明，在2月中下旬一个大小潮周期中，东风西沙水库、陈行水库和青草沙水库取水口盐度大于0.45的不宜取水时间分别为7.74、3.08和2.72 d. 同时，在东线和中线工程短期调水1 000 m³/s情况下，长江河口盐水入侵加剧，尤其在北港、北槽和南槽拦门沙区域及其北支上段盐度上升最为明显，出现了量值超过0.5的大面积区域，南支淡水区域减小. 在2月中下旬一个大小潮周期中东风西沙水库、陈行水库和青草沙水库不宜取水的时间分别增长了1.43、2.14和2.13 d. 在东线和中线工程远期调水1 600 m³/s情况下，整个河口盐度的上升更为明显，在北港、北槽和南槽拦门沙出现了盐度超过1的大范围区域，小范围区域盐度超过了1.5，南水淡水范围进一步减小. 在2月中下旬一个大小潮周期中东风西沙水库、陈行水库和青草沙水库不宜取水的时间分别增加了1.49、3.08和3.08 d.

关键词: 长江河口, 南水北调工程, 盐水入侵, 淡水资源, 数值模拟

Abstract: The South-to-North Water Diversion Project is an interbasin water diversion project, whose impact on changes in freshwater resources in the Changjiang Estuary is of widespread interest. In this paper, we used a 3D numerical model of estuarine saltwater intrusion to study the impact on saltwater intrusion and freshwater resources in the Changjiang Estuary from both short-term and long-term perspectives. The study, moreover, was focused on the eastern and middle route water transfer schemes of the Project. The results indicate that during the neap-spring tide period in mid-to-late February, the unavailable water intake time, corresponding to salinity greater than 0.45 at the water inlets of the Dongfengxisha, Chenhang, and Qingcaosha is 7.74, 3.08, and 2.72 days, respectively. In the case of a short-term water transfer scheme at river discharge of 1 000 m³/s, saltwater intrusion is intensified, especially at the river mouths of the North Channel, North and South Passages, and in the upper reaches of the North Branch, where salinity rise is most noticeable and a large area shows a salinity rise greater than 0.5; meanwhile, the supply of freshwater in the South Branch decreases. During the neap-spring tide period in mid-to-late February, the unavailable water intake time at the water inlets of the Dongfengxisha, Chenhang and Qingcaosha Reservoirs increases by 1.43, 2.14 and 2.13 days, respectively. In the case of long-term water transfer schemes at river discharge of 1 600 m³/s, the salinity rise in the entire estuary is even more noticeable; a large area of salinity rise greater than 1 shows up on the river mouths of the North Channel, North and South Passages, and a small area of salinity rise greater than 1.5. The supply of freshwater in the South Branch also decreases. During the neap-spring tide period in mid-to-late February, the unavailable water intake time at the water inlets of Dongfengxisha, Chenhang, and Qingcaosha Reservoirs increases by 1.49, 3.08, and 3.08 days, respectively.

Key words: Changjiang Estuary, South-to-North Water Diversion Project, saltwater intrusion, freshwater resource, numerical model

中图分类号:

P731.2

苏爱平, 吕行行, 吴宇帆. 南水北调工程对长江口盐水入侵和淡水资源的影响[J]. 华东师范大学学报（自然科学版）, 2020, 2020(3): 32-42.

SU Aiping, Lü Hanghang, WU Yufan. Impact of the South-to-North Water Diversion Project on saltwater intrusion and freshwater resources in the Changjiang Estuary[J]. Journal of East China Normal University(Natural Science), 2020, 2020(3): 32-42.

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