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[目的]岸线形态影响近岸水体的水动力状况、沉积过程、微生境及植被特征,对近岸沉积物的物理与化学特征有直接影响,研究其与近岸底泥元素空间分布的相互关系,用以指导滨岸带的生态修复.[方法]以太湖北部贡湖湾退圩还湖修复项目区为研究对象,分别在项目区选取凹形、凸形和平直形3种岸线形态,按浅滩区、浅水区和深水区3个水深梯度采集样品,分析了不同微生境条件下底泥的粒级结构特征和总磷(TP)、总氮(TN)、有机碳(OC)的含量.[结果]①凹形、凸形岸线形态段不同水深梯度带间底泥粒级结构的差异均较大,而平直岸线段底泥粒级结构在水深梯度上的变化幅度相对较小,且不同岸线形态段间随水深的变化趋势不同,近岸底泥平均粒径在凸形岸线段随水深增加而增加,在凹形岸线段随水深增加而下降;②滨岸带近岸表层底泥中TN、TP、OC含量在凹形、凸形岸线形态段随水深的变化总体上大于平直岸线段,凹形和凸形岸线段近岸深水区TN、有机碳含量最高,TP在凸岸线段浅水区最低;③冗余分析发现,岸线形态与植被状况(植被类型、水深、植被盖度)是影响近岸底泥中TN、TP和有机碳含量的主要影响因子,而底泥的粒级结构特征与底泥中TN、TP和OC含量的相关性相对较小.[结论]与平直岸线相比,相对曲折的岸线形态更有利于增加不同水深梯度带底泥的异质性,对底泥元素的空间分布格局有显著影响.在湖滨带生态修复时,通过构建相对曲折的岸线形态,可有效促进不同水深底泥TN、TP、有机碳的再分配.“,”[Objective]The association between shoreline morphology and distribution patterns of elements in near?shore sediments is significant for riparian ecological restoration as shoreline morphology can influence physical and chemical characteristics of near?shore sediments by affecting hydrodynamic conditions, sedimentary processes, microhabitats and vegetation characteristics. [Method]Here, we collected surface sediments from three shoreline areas with distinct mor?phological shapes (i.e., concave, convex and straight), at three water?depth gradients in the “Returning Embankment to Lake Area Projection” area in Gonghu Bay, the Taihu Lake. [Result] ① The size structure of sediments across the water?depth gradients showed large differences at the concave and convex shorelines, but only smaller differences at the straight shoreline. The size structure showed different trends for the three types of shoreline morphology. The mean grain size of the convex shoreline increased with increasing depth of the water, but decreased with water depth at the concave shoreline. ② The variation in total nitrogen (TN), total phosphorus (TP) and organic carbon (OC) content across the three water?depth gradient zones was generally greater at the concave and convex shorelines than at the straight shoreline. The TN and OC content was the highest in deep water at concave and convex shorelines, and TP content was the lowest in shallow water at the convex shoreline. ③ The redundancy analysis showed that shoreline morphology and vegetation status (i.e., vegetation types, water depth and vegetation coverage) were the main factors influencing TN, TP and OC content, whereas the size structure characteristics of sediments was the least influential factor. [Conclusion]The curved shorelines increased the heterogeneity of sediment in different water?depth gradient zones, which exerted a significant in?fluence on the spatial distribution patterns of elements in sediments. Therefore, constructing relatively curved shorelines can affect the redistribution of TN, TP and OC, thereby promoting riparian ecological restoration.