大连市地表水时空分布特征及其影响因素

The Spatiotemporal Distribution Characteristics and Influencing Factors of Surface Water in Dalian

(目的)分析大连市地表水时空分布特征及其影响因素,为流域水生态管控规划提供依据。(方法)采用斯皮尔曼秩次相关法检验特征指标质量浓度的时间变化趋势。(结果)2013~2022年大连地区主要河流水质总体稳定,大部分河流历年水质以优为主,监测断面的氨氮、化学需氧量基本稳定在Ⅱ类及以上水平,个别年份偶有升高。氨氮2016年前上升(p<0.01),之后明显下降(p<0.01),化学需氧量总体稳定(p>0.05),总氮呈明显上升趋势(p<0.01)。(结论)氨氮:复州河上游较高,大沙河、庄河、登沙河下游较高;化学需氧量:5条河流均下游较高;总氮:庄河、登沙河、复州河下游较高,碧流河上游较高。

(Objective)To analyze the spatial and temporal distribution characteristics as well as the influencing factors of surface water in Dalian City,in order to provide a basis for water ecological control planning in the basin.(Methods)The Spearman’s rank correlation method was employed to examine the time variation trend of the quality concentration of the characteristic index.(Results)The water quality of the main rivers in Dalian remained generally stable from 2013 to 2022,with most rivers having excellent water quality over the years.The ammonia nitrogen and chemical oxygen demand at monitoring sections remained stable at level II or above,with occasional increases in some years.Ammonia nitrogen increased before 2016(p<0.01),and then decreased significantly(p<0.01).The overall chemical oxygen demand remained stable(p>0.05),and total nitrogen showed a significant upward trend(p<0.01).(Conclusion)The ammonia nitrogen concentration is higher in the upper reaches of Fuzhou River,and higher in the lower reaches of Dasha River,Zhuanghe River,and Dengsha River.The chemical oxygen demand concentration in all five rivers is relatively high downstream.The total nitrogen concentration is higher in the lower reaches of Zhuanghe,Dengsha,and Fuzhou rivers,and higher in the upper reaches of Biliu River.