SEDIMENTATION AND RECENT MORPHOLOGICAL CHANGES AT DONGSHA BEACH, ZHUJIAJIAN ISLAND, ZHEJIANG PROVINCE
-
摘要: 砂质海滩是浙江沿海的稀缺资源,以朱家尖岛东沙海滩为例,开展海滩沉积与地貌演变研究,可进一步了解浙江岬湾型海滩发育的区域特性。通过2010-2012年4次地形重复测量对比和沉积物采样分析,结果表明,东沙岸滩沉积地貌相带分布变化明显,沉积物自岸向海分别为砾石、中砂、细砂、粉砂、黏土质粉砂,海滩地貌呈现季节性调整,冬季为滩脊-沟槽地貌,夏季为平坦缓坡地貌,水下岸坡表现为冬淤夏冲。水动力(波浪、潮汐)、沉积物来源和人类活动是影响东沙海滩发育演变的主要因素。崩破波方式和较大的潮差,使东沙海滩呈现为无沙坝发育的消散性状态。丰富的长江入海悬浮泥沙来源,导致东沙海滩粗颗粒砂质沉积物分布范围变小,砂泥分界线向岸靠近。采砂、海塘修筑等人为活动减少和阻断了沿岸粗颗粒沉积物来源,造成海滩侵蚀明显。Abstract: Sandy beaches are precious resources in Zhejiang coastal region. For the purpose to understand the regional sandy beach morphological changes, we selected the Dongsha Beach of Zhujiajian Island as an example. During the period of 2010-2012, we repeated 4 times of topographic survey at the Dongsha Beach. At the same time, sediment samples were collected. Compared with previous beach profiles and the composition of the beach sediments, we discussed the sediment characteristics and the recent morphological changes of the Beach. Sedimentary differentiation is obvious at the Dongsha Beach. From the coastal area to the open sea, we can see the changes of sediments from gravel, medium sand, fine sand, silt, up to clay silt. The beach morphological section shows seasonal changes, with accretion in winter and erosion in summer. The sandy bar and coexisted trough in winter may become a smooth slope in summer. Hydrodynamics, the source of sediments and human activities are the main factors affecting the beach development. Spilling waves and meso-tides often led to a non-barred dissipative beach. Abundant suspending sediment from the Yangtze River resulted in a limited sandy deposition zone and the mudline is close to the shore. Human activities, such as beach sand mining and land reclamation, will change or even block the sand source of the beach resulting in beach erosion.
-
-
[1] Komar P D. Beach processes and sedimentation[M].New Jersey:Prentice Hall, 1998.
[2] Carter R W G. Coastal Environments[M].London:Academic Press, 1988.
[3] Masselink G, Hughes M G. Introduction to Coastal Processes and Geomorphology[M].London:Arnold, 2004.
[4] Dean R D, Robert A Dalrymple. Coastal processes with engineering applications[M]. Cambridge:Cambridge university press,2004.
[5] 王颖,朱大奎.海岸地貌学[M].北京:海洋出版社,1994.[WANG Ying,ZHU Dakui.Coastal Geomophology[M]. Beijing:China Ocean Press, 1994]
[6] 蔡峰,戚洪帅,夏东兴.华南砂质海滩动力地貌过程[M].北京:海洋出版社,2008.[CAI Feng, QI Hongshuai, XIA Dongxing. Morphodynamical processes of sandy beaches in South China[M].Beijing:China Ocean Press, 2008]
[7] 戴志军,李春初.华南弧形海岸动力地貌过程[M].上海:华东师范大学出版社,2008.[DAI Zhijun,LI Chunchu. Morphodynamical processes of arc-shaped coast in South China[M].Shanghai:Press of East China Normal University,2008.
[8] 夏小明.中国海岛(礁)名录[M].北京:海洋出版社,2012.[XIA Xiaoming. Dictionary of China's island&reef[M]. Beijing:China Ocean Press, 2012]
[9] 中国海湾志委员会.中国海湾志(第五分册)[M].北京:海洋出版社,1992.[Edition committee of the bay chorography in China. The bay chorography in China:Vol V[M]. Beijing:China Ocean Press, 1992]
[10] 浙江省海岛资源综合调查领导小组.浙江省海岛资源综合调查与评价[M].杭州:浙江科学技术出版社,1995.[The island resources synthesis investigation leading groups in Zhejiang Province. Synthesis investigation and research of island resources in Zhejiang Province[M]. Hangzhou:Science and Technology Press of Zhejiang,1985.]
[11] Folk L R,William C. Ward Brazos River bar[Texas]:a study in the significance of grain size parameters[J].Journal of Sedimentary Research,1957,27(1):3-26.
[12] 朱静昌,张国栋,王益友等.舟山现代滩脊(坝)沟槽体系迁移与沉积特征[J].海洋与湖沼,1988,19(1):35-45.
[ZHU Jingchang, ZHANG Guodong, WANG Yiyou, et al. Migration of ridge(bar) runnel systems and the resultant sedimentary characteristics on modern coast, Zhoushan archipelago[J]. Oceanologia et limnologia sinica, 1988,19(1):35-45.]
[13] [14] 王雷,李晓丽,徐哲永.近50年影响舟山的台风气候特征分析[J].海洋预报,2011,28(5):36-43.
[WANG Xiaolei, LI Xiaoli, XU Zheyong, Analysis on climatic characteristics of typhoon over the past 50 years at Zhoushan[J]. Marine Forecasts, 2011, 28(5):36-43.]
[15] Guza R T,Inman D L.Edge waves and beach cusps[J].Journal of Geophysical Research.1975.80(21):2997-3012.
[16] Wright L D, Short A D. Morphodynamic variability of surf zones and beaches:a synthesis[J].Marine Geology, 1984, 56:93?118.
[17] Davis J L.A morphogenic approach to world shorelines[J].Zeitschrift für Geomorphology,1964,8(127):127?142.
[18] Masselink G, Short A D. The Effect of Tide Range on Beach Morphodynamics and Morphology:A Conceptual Beach Model[J].Journal of Coastal Research,1993,9(3):785-800.
[19] Wright L D, Nielsen P, Shi N C. Morphodynamics of a bar-troughs surf zone[J].Marine Geology, 1986,70, 251-285.
-
计量
- 文章访问数: 1394
- PDF下载数: 2
- 施引文献: 0
下载: