江苏盐城近海表层沉积物侵蚀特征及影响因素OA
Erosion and its influencing factors of surface sediments nearshore of Yancheng,Jiangsu
江苏盐城海岸是中国最大的粉砂淤泥质海岸之一,近年来处于侵蚀状态.沉积物侵蚀特征是影响海岸侵蚀的重要因素之一,目前尚未开展系统研究.本文利用微观侵蚀系统(U-GEMS)对江苏盐城潮间带和潮下带原状沉积物进行了微观侵蚀实验,探讨了其影响因素.结果表明,潮间带和潮下带沉积物侵蚀特征存在明显差异.潮间带沉积物临界侵蚀剪应力介于 0.2~0.6 N/m2,在 0.6 N/m2 剪应力下的侵蚀速率介于 0.053~0.263 g·m-2·s-1;潮下带沉积物临界侵蚀剪应力介于 0.3~0.69 N/m2,在 0.6 N/m2 剪应力下的侵蚀速率介于 0.051~0.078 g·m-2·s-1.黏土含量是沉积物可侵蚀性和侵蚀模式的主要控制因素,含水率和干容重对于黏性沉积物侵蚀特征影响较大,对非黏性沉积物的侵蚀特征影响不明显.受沉积环境、水动力特征等因素影响,研究区潮间带可侵蚀性显著高于潮下带.该研究丰富了近海冲淤演化理论,可为海岸侵蚀防护和海岸带的可持续发展提供指导.
The coast of Yancheng,Jiangsu is one of the largest silty muddy coasts in China and has been in an erosional state in recent years.The sediment erosion are one of the important factors affecting coastal erosion,for which this systematic research was carried out yet.The micro-erosion system(U-GEMS)was used in our field ex-periment on the undisturbed sediments in the intertidal and subtidal zones in 2023,and the influencing factors were discussed.Results show that the critical erosion shear stress of intertidal sediments was between 0.2 and 0.6 N/m2,and the erosion rate under a shear stress of 0.6 N/m2 was between 0.053 and 0.263 g·m-2·s-1.The critical erosion shear stress of subtidal sediments was between 0.3 and 0.69 N/m2,and the erosion rate under a shear stress of 0.6 N/m2 was between 0.051 and 0.078 g·m-2·s-1.Clay content was the main controlling factor of sediment erodibility and erosion pattern.Moisture content and dry bulk density had a significant impact on the erosion char-acteristics of cohesive sediments,but had little impact on the erosion of non-cohesive sediments.Affected by factors such as sedimentary environment and hydrodynamic characteristics,the erodibility of the intertidal zone in the study area was significantly higher than that of the subtidal zone.The research results are helpful to enrich the theoretical research into nearshore erosion and deposition evolution,and provide guidance for coastal erosion pro-tection and the sustainable development of the coastal zone.
王翼龙;曹阳;朱龙海;聂顺义;胡日军;张晓东;林超然
中国海洋大学海洋地球科学学院,青岛 266100江苏省生态地质调查大队,南京 210000中国海洋大学海洋地球科学学院,青岛 266100中国海洋大学海底科学与探测技术教育部重点实验室,青岛 266100江苏省生态地质调查大队,南京 210000中国海洋大学海洋地球科学学院,青岛 266100中国海洋大学海底科学与探测技术教育部重点实验室,青岛 266100
海洋科学
表层沉积物侵蚀特征微观侵蚀实验影响因素
surface sedimentserosion characteristicsmicro-erosion experimentinfluencing factors
《海洋地质前沿》 2026 (1)
72-86,15
江苏省财政项目"盐城市大丰区典型黄海湿地生态地质资源环境调查评价与利用"(苏财资环[2022]19号)国家自然科学基金(42276172)
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