杨林
, 董玉祥, 黄德全
Yang Lin, Dong Yuxiang, Huang Dequan
中图分类号: P931.3
文献标识码: A
文章编号: 1000-0690（2017）08-1243-08
通讯作者:
收稿日期: 2016-09-8
修回日期: 2016-11-30
网络出版日期: 2017-08-15
版权声明: 2017 《地理科学》编辑部 本文是开放获取期刊文献，在以下情况下可以自由使用：学术研究、学术交流、科研教学等，但不允许用于商业目的.
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作者简介:
作者简介:杨林(1987-),男,江西赣州人,博士研究生,主要从事海岸风沙地貌研究。E-mail: jxyl1988521@163.com
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摘要
依据2014年第10号强台风“麦德姆”登陆前后福建平潭岛典型海岸沙席的形态观测与近表层沉积物粒度数据,综合分析了海岸沙席对台风的响应特征。结果表明：① 海岸沙席形态对“麦德姆”的响应明显,主要表现为沙席前缘高程降低（最大侵蚀深度为0.40 m）,中部变化较小（-0.06~0.09 m）,后缘明显升高（最大堆积厚度为1.62 m）,沙席体积增大2.02%。② 海岸沙席近表层沉积物粒度受“麦德姆”影响较小,其粒度参数在台风前后并无质的等级性变化。③ 海岸沙席的台风响应特征主要因台风过程中大风的非选择性侵蚀和搬运及海岸沙席与海滩沙粒度的相近性所造成的,同时也受到周边地势及植被等的影响。
关键词：
Abstract
Field investigations, including morphology and grain size of the near surface sediment over coastal sand sheet, was conducted at Pingtan Island of Fujian Province before and after the tenth Typhoon “Matmo”landed in 2014. In this article, we analyzed the characteristics of the morphology and grain size of coastal sand sheet responses to typhoon. The results indicated that: 1) The sediment volumes of coastal sand sheet increased 2.02% than before the typhoon “Matmo” landed. Spatially, the main variation of response to typhoon was discovered in the coastal sand sheet. The elevation of beach and frontal coastal sand sheet decreased with the maximum of erosion depth of 0.40 m, few variations of elevation at the middle sites of coastal sand sheet (-0.06 - 0.09 m), and the increase of elevation was found with the maximum accretion of 1.62 m at trailing edge of coastal sand sheet. 2) The grain size parameters have no magnitude variations and the grain size has no significant features of response to Typhoon “Matmo” in the nearsurface sediment of the study area. 3) In the process of the typhoon, the principal factors which influence coastal sand sheet responses to typhoon “Matmo” are the erosion nonselective of strong wind and similarity of grain size of coastal, and the terrain and vegetation around coastal sand sheet also play a role.
Keywords：
台风（国外称飓风或风暴）是海岸风沙地貌形成及演变的一个高能影响因子,也是研究波浪、海滩与沙丘交互作用的重要内容之一[1],尤其是随着观测新技术的运用其对海岸沙丘影响的重要性备受关注[1,2]。目前,国外学者已在欧洲、北美等不同区域开展了大量有关海岸沙丘对风暴（飓风）响应的研究[3~14],其研究主要集中于海岸沙丘形态与沉积物对风暴（飓风）响应及其机理研究。如1999~2002年墨西哥下加利福尼亚半岛Cabo Falso海岸沙丘最大形态变化是由2001年飓风Juliette造成的[9];Wang等[12,13]就2004年飓风Ivan和2005年飓风Dennis对美国佛罗里达海岸沙丘沉积结构变化进行了研究,发现大范围的水平侵蚀面会切断原沙丘低角度的向陆层理,飓风容易改变沙丘层理结构发育模式;Claudino-Sales等[14]研究认为飓风对海岸沙丘的形态改变,不仅取决与飓风强度和持续时间,还受飓风前沙丘形态特点制约,并认为海岸沙丘对飓风响应的差异是飓风强度、持续性、频率和沙丘形态及植被等综合作用的结果。相比而言,国内有关台风对海岸沙丘影响的研究甚为薄弱,仅在研究台风对砂质海滩影响中稍有涉及[15~18],尚未见海岸沙丘对台风响应的研究。
台风（飓风或风暴）对海岸沙丘的影响虽然取得了一定进展,但是国外针对具体不同类型沙丘对飓风（风暴）响应的研究较少,也缺乏对海岸沙丘形态与表层粒度对飓风（风暴）响应的同步综合性研究,国内相关研究亦近属空白。为此,本文在中国海岸沙丘分布典型且深受台风影响的福建省平潭岛,选择国内外研究较少但华南沿海分布较广泛的海岸沙席,基于台风登陆前后的海岸沙席形态观测和近表层沉积物粒度分析数据,综合分析海岸沙席的形态和近表层沉积物粒度对台风的响应特征,以期明晰海岸沙席的台风响应模式,丰富中国海岸沙丘研究内容,并为海岸带保护及管理决策等提供科学依据。
平潭岛又称海坛岛（25°15′N~25°45′ N、119°32′E~120°10′ E）,地处闽中沿海,东濒台湾海峡,为中国第五大岛（图1）。岛上风沙地面积达86.85 km2,发育了形态典型的冢形前丘、横向前丘、海岸沙席、灌丛沙丘和爬坡沙丘等海岸沙丘类型,也是中国海岸沙丘面积较大、类型较多和形态典型的海岸风沙地貌分布区域[19,20]。其中,海岸沙席在平潭岛南部山岐宫最为典型,海岸沙席即一个较宽广平坦或微波起伏的风沙堆积区域,又称沙坪或平沙地,是一种常见的沙丘形态[21]。平潭岛南部山岐宫海岸沙席平面形态似半弧形,长约1 000 m、最宽达200 m,海岸沙席按其形态划分为沙席前缘、沙席中部及沙席后缘,海岸沙席后缘为人工种植的木麻黄（Casuarina equisetifolia）防护林。平潭岛属南亚热带海洋性季风气候,年均气温约19℃,年降水量约1 100 mm,年均风速高达4.8 m/s,每年除3~6月以SSW风向为主外,其余各月的盛行风向均为NNE向,尤其是大风日数多、台风影响大,1981~2010年台风影响平潭岛合计98次,一般每年2~5次,多出现在7~9月,受台风影响最大风速为32.7 m/s,常引发17.2 m/s以上大风,对海岸沙丘形成演化具有重要影响。海岸沙丘类型与形态的典型性和受台风影响的代表性,加之因长期受交通条件等所限人为干扰相对较小,使得平潭岛成为中国海岸风沙地貌对台风响应研究的理想区域之一,故选择其为海岸沙席形态和近表层沉积物粒度台风响应的研究区域。
图1 平潭岛海岸沙席观测样区位置
Fig.1 The location of observation area at coastal sand sheet in Pingtan Island
“麦德姆（Matmo）”为2014年第10号台风,于2014年7月18日02:00在菲律宾以东的西北太平洋面上生成,于23日00:15前后在台湾台东县长滨乡沿海登陆,登陆时为强台风,最大风力达14级（42 m/s）,中心最低气压为955 hPa,然后穿过台湾岛进入台湾海峡。于7月23日15:30前后在福建省福清市高山镇沿海登陆,登陆时减弱为强热带风暴,中心附近最大风力为11级（30 m/s）,中心最低气压为980 hPa,其中心登陆地点距平潭岛最近距离不足30 km,对平潭岛海岸风沙地貌应具有显著的影响与作用。“麦德姆”登陆前后沙席形态及其表层沉积物粒度的变化,对研究海岸沙席形态和表层沉积物粒度对台风的响应极具代表性。
依据海岸沙席的形态特征选择平潭岛山岐宫海岸沙席的典型区段设立了一个约160 m×30 m的观测样区（图1a）。该观测样区的海滩坡度相对较陡,海岸沙席高程向陆逐渐升高,沙席后面是人工种植的木麻黄防护林。样区内设立了3条观测样线（图1b）,并基于观测点位的均匀性设立了214个形态变化高精度测点,同时选择其中84个为近表层沉积物粒度样品采集点,以表征海岸沙席及其典型断面的形态和粒度变化。
海岸沙席样区内观测点形态变化测量采用多站差分RTKGPS技术,该测量技术对海岸沙丘形态的测量精度可达到厘米甚至毫米级[22],已成功应用于海岸沙丘相关研究中[23]。粒度样品采集面积约5 cm×5 cm,深度为2 cm。利用RTKGPS精确的导航功能,分别在“麦德姆”登陆前（2014年7月14日）和登陆后（2014年9月8日）按所设测点进行重复高程测量及粒度采样,获取台风登陆前后观测样区214个测点的高程数据和84个点粒度样品。其中,“麦德姆”登陆后观测和采样时间稍迟,但因该时段风速小（2014年7月25日至9月8日,平潭气象站日平均风速仅3.0 m/s,平均最大风速5.2 m/s）,同时亦未受其它台风影响,海岸沙席受其它因素影响的变化较小,故这两次的形态和粒度数据可以代表“麦德姆”对海岸沙席形态和近表层沉积物粒度的影响与作用。
粒度样品测试采用标准的处理方法：称适量（3~5 g）沙样放入烧杯中;先加入10 mL10%的H2O2,煮沸使其充分反应以去除样品中有机质;再加入10 mL10%的HCl,继续加热使其充分反应以去除样品中的碳酸盐类物质;冷却后给烧杯注满蒸馏水静置24 h,再抽取上部清液,重复操作3次;测试前30 min加入10 mL5%的六偏磷酸钠[(NaPO3)6]溶液使样品充分分散;最后采用Mastersizer2000激光粒度分析仪进行测试,其测试范围0.02~2 000 μm,重复测量误差小于2%。粒级划分按乌登-温特沃斯粒级标准（Udden-Wentworth scale）,粒度参数的计算采用Folk-Ward图解法的公式[24~27]。
3.1.1 测点高程平均变化
对比“麦德姆”登陆前后观察样区内214个测点的高程数据（表1）,全部测点高程变化的平均值为0.14 m,高程最大变化值为1.62 m;除2个测点高程不变外,有117个测点的高程降低,平均降低0.13 m,最大降低值为1.49 m;95个测点的高程升高,平均升高0.16 m,最大升高值为1.62 m。海岸沙席观测样区内的体积由“麦德姆”登陆前的80 663.2 m3变为登陆后的822 291.0 m3,增加了1 627.8 m3,体积增大了2.02%。
表1 海岸沙席观测样区测点高程的平均变化
Table 1 Height average change of observation sample area over coastal sand sheet
| 高程变化 范围（m） | 测点高程变化的 平均值（m） | 高程降低测点 | 高程升高测点 | |||
|---|---|---|---|---|---|---|
| 测点数 | 平均值（m） | 测点数 | 平均值（m） | |||
| -1.49~1.62 | 0.14 | 117 | -0.13 | 95 | 0.16 | |
3.1.2 样线上的高程变化
“麦德姆”登陆后3条观测样线高程变化趋势较为一致（图2）,样线A、B和C上的测点的高程变化的平均值分别为0.17 m、0.09 m、0.07 m。3条样线上测点高程升高与降低值较为相近,各样线上不同部位的高程变化趋势也基本一致,基本表现为海滩及海岸沙席前缘高程降低（最大侵蚀深度0.40 m）,沙席中部（长度98 m）高程变化较小（-0.06~0.09 m）,而在沙席后缘特别是接近木麻黄防护林地带高程明显升高（最大堆积厚度1.62 m）（图3）。
图2 海岸沙席观测样线高程变化
Fig. 2 The height changes of surveying lines over coastal sand sheet
图3 海岸沙席观测样线不同部位的高程变化值
Fig. 3 Height changes value of different sites at the surveying lines over coastal sand sheet
3.2.1 粒度整体变化
对比“麦德姆”登陆前后观测样区内近表层沉积物的粒度数据,总体而言,海岸沙席近表层的粒度组成均以中沙为主,平均含量在50 %以上,其次细沙含量也较高（约29 %）,再次为粗沙、极粗沙、极细沙、粉沙,粘土含量极少,但“麦德姆”登陆后海岸沙席近表层的中沙、粉沙和粘土比例下降,细沙、极细沙和粗沙比例上升,但其构成比例最大变化值仅2.69 %（图4）。同时,平均而言海岸沙席观测样区近表层沉积物粒度参数在“麦德姆”登陆前后并无等级性的变化（表2）,均为中沙、分选较好、近对称和中等峰态,台风登陆前后其近表层粒度样品平均粒径、分选系数、偏态和峰态等粒度参数均值的变化分别仅为0.03 Φ、0.01、0.01、0.01。
图4 海岸沙席近表层沉积物粒度组成变化
Fig. 4 Grain size composition change of the near surface sediment over coastal sand sheet
表2 海岸沙席近表层沉积物粒度参数变化
Table 2 Grain size parameters change of the near surface sediment over coastal sand sheet
| 采样时间 | 平均粒径（Φ） | 分选系数 | 偏度 | 峰度 | |||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| 数值范围 | 平均值 | 数值范围 | 平均值 | 数值范围 | 平均值 | 数值范围 | 平均值 | ||||
| 台风登陆前 | 1.24~2.29 | 1.68 | 0.40~0.86 | 0.53 | -0.10~0.24 | 0.00 | 0.93~1.81 | 0.96 | |||
| 台风登陆后 | 1.21~2.52 | 1.71 | 0.40~0.87 | 0.54 | -0.14~0.01 | -0.01 | 0.93~1.00 | 0.95 | |||
3.2.2 不同部位粒度变化
对比“麦德姆”登陆前后3条观测样线上不同部位近表层沉积物的粒度组成,台风后海滩及沙席前缘近表层沉积物的粒度均为细沙比例大幅度上升,中沙比例下降,粒度组成由以中沙为主变成以细沙为主（图5）,平均粒径由中沙变为细沙,分选性由好变为较好,均为近对称和中等峰态（图6）,但沙席中部和后缘并无质的等级性变化,粒度组成均以中沙为主（图5）,粒度参数也均为中沙、分选较好、近对称和中等峰态（图6）。同时,各样线上不同部位粒度组成的变化程度存在一定的差异,如样线A沙席中部的细沙和粗沙比例下降而中沙比例升高,后缘细沙比例下降而中沙和粗沙比例升高;样线B中部的中沙和粗沙比例下降而细沙比例升高,后缘细沙比例下降而中沙和粗沙比例升高;样线C中部的变化不明显,海岸沙席后缘部的细沙和中沙比例下降而粗沙比例升高（图5）。
图5 海岸沙席近表层沉积物不同粒径在观测样线不同部位的变化
Fig.5 Change of different the near surface sediment grain sizes at the different sites of sample lines over coastal sand sheet
图6 海岸沙席近表层沉积物粒度参数在观测样线不同部位的变化
Fig.6 Change of the near surface sediment grain size parameters at the different sites of sample lines over coastal sand sheet
海岸沙席形态对台风“麦德姆”响应明显,总体积略有增大（2.02%）,海滩及沙席前缘高程降低（最大侵蚀深度为0.40 m）,沙席中部（长度98 m）高程变化较小（-0.06~0.09 m）,但在沙席后缘特别是接近木麻黄防护林地带高程明显升高（最大堆积厚度为1.62 m）。表明海滩及沙席前缘以侵蚀为主,沙席中部侵蚀与堆积保持相对平衡,沙席后缘以堆积为主。受台风“麦德姆”的影响,平潭岛上的风力侵蚀力及其携沙能力极强（台风期间平潭岛最大风力达11级）。山岐宫的海滩及海岸沙席前缘在向岸风和波浪共同侵蚀作用下高程降低,该结果与国内外有关海滩及沙丘前缘对台风（风暴或飓风）响应特征基本一致[3~18];台风登陆后向岸风在向陆推进过程中受逐步升高地势影响风速逐渐降低,尤其是受沙席后缘木麻黄防护林地的阻挡风速急剧下降,随之风力作用从海滩开始以侵蚀为主逐渐转变为侵蚀和堆积相对平衡以致到最后变为以堆积为主,导致海岸沙席形态在台风后表现为海岸沙席前缘高程降低、沙席中部高程变化相对较小、沙席后缘高程升高,海岸沙席总体积也因接受来自岸线附近海滩的沙物质略有所增大。充分说明,海岸沙席形态对台风的响应,是台风、地势和植被等因子综合作用的结果[14],其中台风强劲的风力侵蚀和搬运作用是起主导作用的决定性因子。
比较而言海岸沙席近表层沉积物粒度对台风“麦德姆”的响应并不明显,其粒度参数基本无质的等级性变化,如整体而言海岸沙席粒度组成在“麦德姆”登陆前后均以中沙为主,粒度参数均为中沙、分选较好、近对称和中等峰态,只有沙席前缘近表层沉积物粒度组成受“麦德姆”影响由中沙变成以细沙为主,平均粒径由中沙变为细沙,分选性由好变成较好,但均为近对称和中等峰态。究其原因,风沙沉积物粒度特征主要受控于源区物质粒度组成和风况,其沉积物粒度特征存在空间上表现为沿主导风向由物源区向沉积区沙粒变细、分选性变好的规律[28]。但平潭岛海岸风沙沉积物属于形成时代较晚的近源沉积,在季风气候的风向交替、台风频发和风沙活动空间有限等因素共同作用下致使其风沙沉积物对其物源海滩沙的继承性较强,致使二者粒度特征相近且难以有效区分[29,30]。“麦德姆”虽对海岸沙席近表层沉积物产生了一定分异作用,如因风力侵蚀和搬运作用出现一定程度的粒度组成变化,但因粒度特征相近且在台风强风作用下主要是对海岸沙席近表层大小颗粒不加选择的侵蚀和搬运,风成沙混杂堆积,导致台风对海岸沙席近表层粒度的影响难以有效体现,因而造成其粒度在台风“麦德姆”登陆前后整体而言并无质的等级性差别。表现出的主要粒度变化差异是受“麦德姆”影响沙席前缘近表层沉积物粒度变细沙、分选性变差,与童宵岭等[18]对浙江皇城正切段海滩沉积物粒度对台风“海葵”响应研究结果较为一致,其主要可能是台风过境后离岸风（盛行风向）从沙席后缘和中部搬运的细沙沉积于此,或与台风后后期向岸风的作用等有关,其原因亟待进一步观测研究。
1） 海岸沙席形态对台风的响应明显,总体表现为受“麦德姆”影响海岸沙席体积略有所增大（2.02%）,沙席前缘高程降低（最大侵蚀深度为0.40 m）,沙席中部高程变化较小（-0.06~0.09 m）,但沙席后缘特别是接近木麻黄防护林地带高程明显升高（最大堆积厚度为1.62 m）,表明海岸沙席对台风的形态响应是台风、地势和植被等因子综合作用的结果,其中台风的强劲风力侵蚀和搬运作用是主导性因子。
2） 海岸沙席近表层沉积物粒度受“麦德姆”影响较小,总体而言台风前后其粒度参数无质的等级性变化,其中研究区内海岸沙席风成沙与海滩沙粒度的相近性及台风过程中大风的非选择性侵蚀和搬运是造成海岸沙席近表层沉积物粒度对台风响应程度不够明显的根本原因。
The authors have declared that no competing interests exist.
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The coastal aeolian geomorphic types and their distribution pattern in China.
通过对我国海岸风沙地貌类型体系及其分布规律的分析总结,提出了一个包括2类、3亚类和13个三级形态类型的中国海岸风沙地貌分类体系,简要介绍了各类海岸风沙地貌的分布,总结了我国海岸风沙地貌的分布特点及其规律。结果表明,我国海岸风沙地貌具有分布范围广泛,规模较小且分布零散,分布地形多样,河口地区分布较集中,区域特征显著,类型与规模差异较大等特点,究其原因是由各地的沙源、气候与地势等海岸风沙地貌形成发育条件的差异造成。
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多站差分RTKGPS技术在海岸风沙观测中的应用 [J].The application of multi-station RTKGPS in the measurement of coastal dune. |
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海岸新月形沙丘移动与形态变化的典型研究 [J].
<p>依据2006~2008 年连续3 a 共9 次采用RTK GPS技术与测量方法对一个典型海岸新月形沙丘形态的高精度测量数据，分析了海岸新月形沙丘的移动方向、方式、速度以及形态变化特点。结果表明，海岸新月形沙丘具有缓慢、向陆往复式前进的移动特点，形态变化则具有随季节增减变化中高度、宽度、长度、断面面积与体积增加的加积特征，究其原因是区域风况、海岸地表覆被、沙丘形态及人类活动等共同作用的结果。</p>
Typical research on the movement and topographic change of coastal crescent dune.
<p>依据2006~2008 年连续3 a 共9 次采用RTK GPS技术与测量方法对一个典型海岸新月形沙丘形态的高精度测量数据，分析了海岸新月形沙丘的移动方向、方式、速度以及形态变化特点。结果表明，海岸新月形沙丘具有缓慢、向陆往复式前进的移动特点，形态变化则具有随季节增减变化中高度、宽度、长度、断面面积与体积增加的加积特征，究其原因是区域风况、海岸地表覆被、沙丘形态及人类活动等共同作用的结果。</p>
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Brazos river bar: a study in the significance of grain size parameters [J].https://doi.org/10.1306/74D70646-2B21-11D7-8648000102C1865D URL [本文引用: 1] 摘要
No abstract available
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Grain size characteristics in the Hexi Corridor Desert [J].https://doi.org/10.1016/j.aeolia.2015.05.006 URL 摘要
This study investigates grain-size characteristics on the dune surfaces in the Hexi Corridor Desert, a little-researched area of northwestern China. Grain-size parameters (mean, standard deviation, skew, and kurtosis) were determined on dune surfaces at the windward toe, stoss, crest, and leeward toe. Multiple discriminant analyses were applied to distinguish deposition environments. Results indicated that the aeolian sediment in the Hexi Corridor Desert is mainly composed of very fine and fine sand (0.07mm卤0.01 to 0.24mm卤0.06). Sorting improves as grain size becomes finer. However, mean grain size increased with skew, but decreased with kurtosis. There is a good negative correlation between skew and sorting. However, there is no correlations between sorting and skew, and skew and kurtosis. The sediment deposition environment includes aeolian, lacustrine and alluvial sediments. The lacustrine sediment provides the source material for the formation and development of dune windward toes and stoss, but the aeolian sediment provides the source material for the formation and development of dune crest and leeward toes. Based on log-probability of grain size distributions, aeolian sediments in dune networks are composed of two distinct saltation populations. Sand sources affect the mean grain size changed from upwind to downwind, medium sand decreases and fine sand, very fine sand, and silt and clay increase, sand sediment become finer from upwind to downwind. There are three types of mean sand grain sizes over dune surface: coarser crest (69%), finer crest (24%), or no difference (7%) with windward slope and leeward slope.
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毛乌素沙漠东南缘滴哨沟湾剖面DGS1层段粒度特征及其指示的全新世气候变化 [J].https://doi.org/10.13249/j.cnki.sgs.2016.03.017 URL Magsci 摘要
<p>分析滴哨沟湾剖面全新统DGS1段的粒度数据,认为流动沙丘砂、泥炭、砂质古土壤、古固定<i>-</i>半固定沙丘砂到湖沼相和次生黄土的颗粒总体上变细,分选变差。结合腹足类动物化石和湖沼相地层中石英砂粒表面电镜扫描,认为DGS1粒度结果实际上是全新世以来多次冬夏季风的交互演替过程的气候<i>-</i>地质记录。据此,将DGS1粒度信号记录的全新世气候分为4个阶段——全新世早期好转期、全新世鼎盛期、大暖期向寒冷期转变波动期和降温不稳定的沙漠化频繁变化时期。</p>
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海岸风沙地貌台风响应研究的现状与趋势 [J].https://doi.org/10.7522/j.issn.1000-694X.2013.00366 URL Magsci [本文引用: 2] 摘要
基于台风对海岸风沙地貌影响研究发展的简要回顾，概括了国外近期在海岸沙丘风暴响应的差异性及其机理、风暴响应沉积特征以及新技术应用等方面的主要进展，认为国内适时开展台风对海岸风沙地貌形态与沉积特征影响研究十分必要，建议以华南为研究区域，通过对台风前后不同类型海岸沙丘形态变化的高精度测量、非台风季风沙运动过程的定位观测以及沙丘沉积物的系统采样分析等，研究华南海岸风沙地貌形态和沉积变化与台风间的相互联系，探究台风对华南海岸风沙地貌的作用规律，建立华南海岸风沙地貌的台风响应模式。
Review on the typhoon effect on coastal aeolian landforms. https://doi.org/10.7522/j.issn.1000-694X.2013.00366 URL Magsci [本文引用: 2] 摘要
基于台风对海岸风沙地貌影响研究发展的简要回顾，概括了国外近期在海岸沙丘风暴响应的差异性及其机理、风暴响应沉积特征以及新技术应用等方面的主要进展，认为国内适时开展台风对海岸风沙地貌形态与沉积特征影响研究十分必要，建议以华南为研究区域，通过对台风前后不同类型海岸沙丘形态变化的高精度测量、非台风季风沙运动过程的定位观测以及沙丘沉积物的系统采样分析等，研究华南海岸风沙地貌形态和沉积变化与台风间的相互联系，探究台风对华南海岸风沙地貌的作用规律，建立华南海岸风沙地貌的台风响应模式。
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Climate variations recorded by the grain-size from the DGS1 segment in the southeast of China’s Mu us desert during the holocene. https://doi.org/10.13249/j.cnki.sgs.2016.03.017 URL Magsci 摘要
<p>分析滴哨沟湾剖面全新统DGS1段的粒度数据,认为流动沙丘砂、泥炭、砂质古土壤、古固定<i>-</i>半固定沙丘砂到湖沼相和次生黄土的颗粒总体上变细,分选变差。结合腹足类动物化石和湖沼相地层中石英砂粒表面电镜扫描,认为DGS1粒度结果实际上是全新世以来多次冬夏季风的交互演替过程的气候<i>-</i>地质记录。据此,将DGS1粒度信号记录的全新世气候分为4个阶段——全新世早期好转期、全新世鼎盛期、大暖期向寒冷期转变波动期和降温不稳定的沙漠化频繁变化时期。</p>
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克里雅河中下游流域地表沉积物的粒度与化学元素空间分布 [J].https://doi.org/10.13249/j.cnki.sgs.2016.08.019 URL Magsci [本文引用: 1] 摘要
<p>通过对克里雅河流域的实地考察、地形测量、取样,分析其流经沙漠过渡带地表沉积物的粒度、化学元素的空间分布,得出以下结论：河流—沙漠过渡带地表沉积物的粒度组成以>2 φ的粒径为主,粒度特征明显表现出风成特点;化学组成上以Si、Al为主,和上陆壳平均化学组成相比,除Ca、Co、As外都有一定的亏损;不同河段自上游至下游,在不同动力条件下,地表物质粒度特征表现出河漫滩砂与阶地风成砂呈相反的递变趋势;不同河段A-CN-K图解及CIA揭示了克里雅河不同河段地表物质化学风化程度均很低,处于较弱的去Na、Ca阶段,其他元素未发生明显的化学风化或迁移,不同河段化学风化程度差异与物源及地貌格局息息相关;同一河段不同地貌单元,随距河道远近不同,粒度特征与化学风化程度呈现出一定的递变规律;克里雅河平均粒径与一些元素的相关性,说明粒径大小与表征化学风化程度数值的大小有一定关系。总之,在不同空间尺度上,克里雅河地表沉积物理化学特征的分异实质上反映风动力和水动力的差异性分选。</p>
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A review of field methods to survey coastal dunes—experience based on research from South Baltic coast [J].https://doi.org/10.1007/s11852-016-0428-x URL [本文引用: 1] 摘要
The aim of this paper is to compare the usefulness of equipment employed for foredune ground surveys in different environmental conditions based on literature and field experience from the Polish coas
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Morphological barrier island changes and recovery of dunes after Hurricane Dennis, St. George Island, Florida [J].https://doi.org/10.1016/j.geomorph.2009.09.022 URL [本文引用: 2] 摘要
During the summer of 2005, Hurricane Dennis overwashed the eastern portion of St. George Island, part of the northwest barrier island chain located along the Florida Panhandle. In this paper, LiDAR-based morphological changes of the barrier island are analyzed, along with the short-term post-storm recovery of secondary dunes. Results show that overwash from the storm surge removed nearly the entire foredune complex, and the initial breaching probably occurred where the complex was either low or discontinuous; in these locations, beach widening was less. In contrast, approximately 1002m of beach widening occurred where foredunes were higher and continuous, implying that more sediment was available for seaward transport during storm conditions. The secondary dunes recovered at an average linear rate of 3–402cm per month in the presence of vegetation, although monthly averages varied from 61021.5 to 1.402m 3 /m and total volume changes varied from 610217.9 to 16.402m 3 /m for the duration of the study. Furthermore, vegetation deterred dune migration, thus favoring dune growth and reducing erosion due to wind. In contrast, the absence of vegetation inhibited dune growth. Insignificant changes in elevation occurred in areas of storm debris or lag deposit. Finally, distributions of topographic gradients and curvature calculated numerically from pre- and post-storm LiDAR data are introduced as a potential tool in determining the relative post-storm recovery of the dune field.
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Post-storm beach and dune recovery: Implications for barrier island resilience [J].https://doi.org/10.1016/j.geomorph.2014.12.044 URL 摘要
The ability of beaches and dunes to recover following an extreme storm is a primary control of barrier island response to sea-level rise and changes in the frequency and/or magnitude of storm surges. Whereas erosion of the beach and dune occurs over hours and days, it can be years to decades before the beach and dune are able to recover to their pre-storm state. As a consequence, there are numerous descriptions of near-instantaneous beach and dune erosion due to storms, the immediate onshore transport of sand, and the initial phases of beach and dune recovery following a storm, but a paucity of data on long-term beach and dune recovery. A combination of previously published data from Galveston Island, Texas and new remotely sensed data from Santa Rosa Island, Florida is used in the present study to quantify the rate of dune recovery for dissipative and intermediate beach types, respectively. Recovery of the dune height and volume on Galveston Island was observed within two years following Hurricane Alicia (1983) and was largely complete within six years of the storm, despite extensive washover. In contrast, the dunes on Santa Rosa Island in Northwest Florida began to recover four years after Hurricane Ivan (2004), and only after the profile approached its pre-storm level and the rate of vegetation recovery (regrowth) was at a maximum. Results show that complete recovery of the largest dunes (in height and volume) will take approximately 10聽years on Santa Rosa Island, which suggests that these sections of the island are particularly vulnerable to significant change in island morphology if there is also a change in the frequency and magnitude of storm events. In contrast, the areas of the island with the smallest dunes before Hurricane Ivan exhibited a rapid recovery, but no further growth in profile volume and dune height beyond the pre-storm volume and height, despite continued recovery of the largest dunes to their pre-storm height. A change in storm magnitude and/or frequency is a potential threat to barrier island resilience, particularly for those sections of the island where dune recovery has historically taken the longest time. Further study is required to determine how and why dune recovery varies for the dissipative and intermediate beaches of Galveston Island and Santa Rosa Island, respectively.
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| [5] |
Impact of the winter 2013-2014 series of severe Western Europe storms on a double-barred sandy coast: Beach and dune erosion and megacuspembayments [J].https://doi.org/10.1016/j.geomorph.2015.03.006 URL 摘要
The winter of 2013/2014 was characterized by a striking pattern of temporal and spatial extreme storm wave clustering in Western Europe. The 110-km long Gironde coast, SW France, was exposed to the most energetic wave conditions over the last 1802years. The period was outstanding in terms of the available energy to move sediment and cause large-scale erosion with the 2-month average significant wave height ( H s ) exceeding 3.602m, just below the 0.95 quantile, and 4 distinct 10-year return period storms with H s 02>02902m. These storm waves caused unprecedented beach and dune erosion along the Gironde coast, including severely damaged sea defences at the coastal towns. At the end of the winter, dune erosion scarp height was highly variable alongshore and often exceeded 1002m. Megacusp embayments were observed along the Gironde coast with an average alongshore spacing of 100002m in the south progressively decreasing to 50002m in the north, with an average cross-shore amplitude of 2002m. While beach megacusps were previously observed to systematically couple to the inner bar along the Gironde coast during low- to moderate-energy wave conditions, severe storm-driven megacusp embayments cutting the dune were found to be enforced and coupled to the outer crescentic bar. A detailed inspection of the 150002m-long bimonthly topographic surveys of Truc Vert beach shows that in early January 2014 the outstanding shore-normal incident storm swell ‘Hercules’, with H s and peak wave period T p peaking at 9.602m and 2202s, respectively, triggered the formation of a localized megacusp embayment with the erosion scarp height exceeding 602m in its centre where the dune retreat reached 3002m. The subsequent storms progressively smoothed the megacusp by the end of the winter, mostly through severe erosion of the megacusp horns. Because of the very long period (1602s02<02 T p 02<022302s) storm waves with persistent shore-normal incidence, the well-developed outer crescentic bar observed prior to the winter did not straighten. Instead, the outer-bar three-dimensionality developed further, particularly during ‘Hercules’. Our observations indicate that both the antecedent outer sandbar morphology and storm wave characteristics, including period and angle of incidence, govern patterns of beach and dune erosion along open multiple-barred sandy coasts during severe storms.
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| [27] |
Spatial distribution characteristics of the grain size and geochemical elements of surface sediments in the keriya river. https://doi.org/10.13249/j.cnki.sgs.2016.08.019 URL Magsci [本文引用: 1] 摘要
<p>通过对克里雅河流域的实地考察、地形测量、取样,分析其流经沙漠过渡带地表沉积物的粒度、化学元素的空间分布,得出以下结论：河流—沙漠过渡带地表沉积物的粒度组成以>2 φ的粒径为主,粒度特征明显表现出风成特点;化学组成上以Si、Al为主,和上陆壳平均化学组成相比,除Ca、Co、As外都有一定的亏损;不同河段自上游至下游,在不同动力条件下,地表物质粒度特征表现出河漫滩砂与阶地风成砂呈相反的递变趋势;不同河段A-CN-K图解及CIA揭示了克里雅河不同河段地表物质化学风化程度均很低,处于较弱的去Na、Ca阶段,其他元素未发生明显的化学风化或迁移,不同河段化学风化程度差异与物源及地貌格局息息相关;同一河段不同地貌单元,随距河道远近不同,粒度特征与化学风化程度呈现出一定的递变规律;克里雅河平均粒径与一些元素的相关性,说明粒径大小与表征化学风化程度数值的大小有一定关系。总之,在不同空间尺度上,克里雅河地表沉积物理化学特征的分异实质上反映风动力和水动力的差异性分选。</p>
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| [28] |
巴丹吉林沙漠地表沉积物粒度特征及区域差异 [J].
<FONT face=Verdana>对巴丹吉林沙漠不同区域、不同类型沙丘、不同地貌部位的223个地表沉积物样品进行粒度分析表明,该沙漠的流动沙丘主要由细沙组成,其含量可达49.5%～66.1％；沙丘沙的平均粒径介于2.104～2.706 Φ之间,粗于塔克拉玛干沙漠和腾格里沙漠,与世界其他沙海中沙物质粒径相比处于中等粗细。粒径最细者为灌丛沙丘表面沙粒,最粗者为横向沙山迎风坡；分选度好至极好,均为正偏中等峰态。丘间地物质粗于沙丘沙,平均粒径为1.409 Φ,分选较好,正偏窄峰态。从频率曲线来看,沙丘沙为单峰,丘间地多为双峰或三峰。在典型横向沙山剖面上,自迎风坡坡脚至沙丘顶部平均粒径变细而分选性变好,最粗的沙粒出现在靠近迎风坡坡脚的丘间地,而最细和分选最好的沙粒出现在紧邻沙丘顶部的背风坡。尽管横向沙山与新月形沙丘和沙丘链的尺度不同,但二者同属横向沙丘系统,具有相似的沙丘动力机制,因而粒度参数之间关系的表现趋同。从区域上来看,在平行于主导风向的3条NW—SE向断面上,沙漠中北部高大沙山之间低矮“通道”上的沙粒平均粒径存在微弱的变细趋势,而高大沙山区则不存在明显的变化规律；在平行于雅布赖山的3条SW—NE向断面上,粒度参数沿断面方向无明显的变化规律,但断面越靠近雅布赖山平均粒径越粗。一般认为巴丹吉林沙漠是中国重要的沙尘源区之一,然而粒度分析结果表明,沙漠中北部几乎不含粉沙黏土（<0.0625 mm）组分,而东南部的横向沙山区含量则相对较高,这就需要进一步推断巴丹吉林沙漠具体的沙尘源区和沙尘释放过程。以上变化规律说明,除了物源和主导风向等宏观因素外,引起局地气流改变进而影响沙粒跃移过程的地形起伏、植被覆盖等微观因素也对沙粒分选过程起着重要的控制作用；宏观和微观因素共同作用,最终形成的粒度参数规律性在沙丘尺度上要好于区域尺度上。该粒度分析结果,对于分析巴丹吉林沙漠沙物质来源和形成演变过程、反演高大沙山形成机理、估算地表沙尘释放量等均具有重要参考意义。</FONT>
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| [6] |
Comparison of storm cluster vs isolated event impacts on beach/dune morphodynamics [J].https://doi.org/10.1016/j.ecss.2015.07.040 URL 摘要
Two-dimensional numerical simulations were used to investigate the impacts of storm clustering on the beach/dune evolution of the Sefton coast, Liverpool Bay, UK. A storm cluster consisting of a series of closely spaced seven events was identified using observed wave and surge data during the 2013/2014 winter period. First event in this cluster is regarded as exceptionally intense and the occurrence of seven storms within a very short time period, is unique. The XBeach coastal area model was used to simulate beach change from 1) the storm sequence (Clustered events) and 2) the same storms considering them asisolated events. Offshore metadata was transformed to the nearshore area using the Delft3D and SWAN models. Resulting evolution was first compared with the available post-storm profiles measured at a number of locations along the Sefton coast. Analysis of theClusteredandIsolatedsimulations showed the effect of clustering on the Sefton beach/dune system when compared to the impact of isolated events occurring on a fully recovered beach system. Morphological change occurred during each storm in theClusterwas influenced by the preceding storm(s), such that the evolution is not proportional to the storm power of the event, as it would be forIsolatedevents. Both storm cases resulted in heavy erosion at Formby Point (i.e. central of the Sefton coast) and accretion in the north and south. TheClusterprevented system recovery with the area of erosion continually extending south along the coast compared with that inIsolatedevents. The initial storm within theClustercaused large bed level changes in the nearshore ridge-runnel system, enabling the subsequent storms to penetrate further south. The local convex geometry of the Sefton coast is found to have more influence on the beach/dune morphodynamics than the clustering effect. This study enhances the understanding beach/dune response to storm clusters, to interpret observed morphological changes and to develop tools for sustainable coastal management particularly in the Sefton coast and generally in similar systems worldwide.
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| [7] |
Assessment of beach and dune erosion and accretion using LiDAR: Impact of the stormy 2013-14 winter and longer term trends on the Sefton Coast, U K [J].https://doi.org/10.1016/j.geomorph.2016.05.011 URL 摘要
An important question for coastal management concerns the importance of individual storms and clusters of storms on longer term beach sediment budgets, beach and dune erosion, and coastal flood risk. Between October 2013 and March 2014 a series of deep Atlantic low pressure systems crossed the Northeast Atlantic, and strong winds, high waves and high water levels affected many coastal areas in the UK and other parts of western Europe. Net dune recession of up to 12.102m occurred around Formby Point. On 5 December 2013 the highest water level ever recorded at Liverpool (6.2202m ODN) coincided with waves of H s of 4.5502m and T p of 9.302s in Liverpool Bay. Wave trimming of the dune toe occurred along the entire length of the Sefton coast, but significant dune erosion occurred only where the upper beach (between the mean high water spring tide level and the dune toe) was <022502m wide. Sediment budget calculations based on LiDAR surveys in October 2013 and May 2014 indicated a net loss of 12702×0210 3 02m 3 of sediment from the beach (above 002m ODN) and a loss of 26802×0210 3 02m 3 from the frontal dune system, mostly at Formby Point. However, some parts of the beach to the south of Formby Point gained sediment, indicating net north to south transport over the winter. When considered in a longer term context, the 2013–14 winter represents only a small perturbation on the longer-term coast trend of erosion at Formby Point and progradation to the north and south. Analysis of LiDAR data over a longer time period 1999–2014 indicated upper beach and dune sediment loss of 78002×0210 3 02m 3 from the north-central part of Formby Point, with net gains of 80602×0210 3 02m 3 and 211602×0210 3 02m 3 in areas to the north and south, respectively. This indicates a net onshore transport of 214202×0210 3 02m 3 from Liverpool Bay towards the coast between Birkdale and Altcar, with a further net total of 21002×0210 3 02m 3 transported towards the shore between Altcar and Crosby. In view of the demonstrated value of airborne LiDAR surveys for the quantification of storm impacts and longer term coastal changes, it is recommended that such surveys should be undertaken before and after each winter storm period, covering the area between mean low water spring tide level and a line 20002m landward of the dune toe, of as a part of the regional coastal monitoring programme.
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| [28] |
Grain size characteristics and spatial variation of surface sediments in the Badain Jaran desert.
<FONT face=Verdana>对巴丹吉林沙漠不同区域、不同类型沙丘、不同地貌部位的223个地表沉积物样品进行粒度分析表明,该沙漠的流动沙丘主要由细沙组成,其含量可达49.5%～66.1％；沙丘沙的平均粒径介于2.104～2.706 Φ之间,粗于塔克拉玛干沙漠和腾格里沙漠,与世界其他沙海中沙物质粒径相比处于中等粗细。粒径最细者为灌丛沙丘表面沙粒,最粗者为横向沙山迎风坡；分选度好至极好,均为正偏中等峰态。丘间地物质粗于沙丘沙,平均粒径为1.409 Φ,分选较好,正偏窄峰态。从频率曲线来看,沙丘沙为单峰,丘间地多为双峰或三峰。在典型横向沙山剖面上,自迎风坡坡脚至沙丘顶部平均粒径变细而分选性变好,最粗的沙粒出现在靠近迎风坡坡脚的丘间地,而最细和分选最好的沙粒出现在紧邻沙丘顶部的背风坡。尽管横向沙山与新月形沙丘和沙丘链的尺度不同,但二者同属横向沙丘系统,具有相似的沙丘动力机制,因而粒度参数之间关系的表现趋同。从区域上来看,在平行于主导风向的3条NW—SE向断面上,沙漠中北部高大沙山之间低矮“通道”上的沙粒平均粒径存在微弱的变细趋势,而高大沙山区则不存在明显的变化规律；在平行于雅布赖山的3条SW—NE向断面上,粒度参数沿断面方向无明显的变化规律,但断面越靠近雅布赖山平均粒径越粗。一般认为巴丹吉林沙漠是中国重要的沙尘源区之一,然而粒度分析结果表明,沙漠中北部几乎不含粉沙黏土（<0.0625 mm）组分,而东南部的横向沙山区含量则相对较高,这就需要进一步推断巴丹吉林沙漠具体的沙尘源区和沙尘释放过程。以上变化规律说明,除了物源和主导风向等宏观因素外,引起局地气流改变进而影响沙粒跃移过程的地形起伏、植被覆盖等微观因素也对沙粒分选过程起着重要的控制作用；宏观和微观因素共同作用,最终形成的粒度参数规律性在沙丘尺度上要好于区域尺度上。该粒度分析结果,对于分析巴丹吉林沙漠沙物质来源和形成演变过程、反演高大沙山形成机理、估算地表沙尘释放量等均具有重要参考意义。</FONT>
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| [29] |
华南海岸现代风成沙与海滩沙的粒度特征差异 [J].https://doi.org/10.7522/j.issn.1000-694X.2014.00114 URL Magsci [本文引用: 1] 摘要
<p>基于华南海岸沙丘集中分布的闽南、粤东、粤西、海南岛沿岸141个现代沙丘沙和70个海滩沙样品的粒度数据,从粒径组成、粒度参数、粒度参数图和概率累积曲线等方面,分析了华南海岸现代风成沙与海滩沙的粒度差异特点.结果表明:现代沙丘沙较海滩沙细、分选程度变好、正偏相对增多及峰态变窄,但二者的差异并不显著,其概率累积曲线相近且一般通过粒度参数图难以区分,差异程度还呈现出明显的区域性.上述差异主要受华南海岸沙丘发育时间较短、季风气候的风向交替、台风频发、风沙活动空间不足、沙源粗细不同与沙丘规模差别等因素影响.</p>
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| [8] |
Morphological response of a sandy barrier island with a buried seawall during Hurricane Sandy [J].https://doi.org/10.1016/j.coastaleng.2016.01.005 URL 摘要
Coastal populations continue to increase globally, causing potential damage costs of coastal hazards to rise and community resiliency to become a worldwide priority. Recently, Hurricane Sandy (2012) devastated areas of New York and New Jersey and caused overwash and breaching of several urbanized barrier islands along the U.S. eastern seaboard. This study focuses on the morphological response of Bay Head, NJ, a township on a barrier island fronted with a buried seawall. The hydrodynamics and morphology of Bay Head during Hurricane Sandy are simulated with XBeach, a numerical model designed to study these processes during storm events. From the simulations, the seawall protected Bay Head by effectively dissipating wave energy during the peak of the storm and from rapidly increasing bay water levels that flood the backbarrier region of the island. When the seawall is removed from the simulation, dune heights are lowered, allowing bay side flooding to cause a devastating erosive event that completely destroys the remaining dune system. XBeach indicates severe erosion seaward of oceanfront buildings in the absence of a seawall (vertical erosion under the dune peak about 15 m more than in the presence of the seawall), and wave energy propagates further inland even after the storm has passed. However, with the seawall present, wave attack is reduced on the island by a factor of 1.7 and prevents bay side flooding from causing significant morphological change on the island. Therefore, the seawall increased resiliency of the Bay Head community during and after peak Hurricane Sandy forcing by preserving the dune system.
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| [9] |
Dune and beach morphodynamics at Cabo Falso, Baja California Sur, Mexico: Response to natural, Hurricane Juliette (2001) and anthropogenic influence [J].https://doi.org/10.2112/05-0575.1 URL [本文引用: 1] 摘要
Cabo Falso is located on the southern coast of the Baja California peninsula. The beach is broad and wide with a steep face and tall foredunes on the backshore. Landwards, an active, predominantly parabolic dune field has developed with average heights of 30 m. Part of the field is used by recreational all-terrain vehicles. The main goal of this study was to identify the principal morphodynamic characteristics of the deposits influenced by these recreational activities and affected by Hurricane Juliette in 2001. The morphology of the study area was monitored using seasonal topographic profiles, examination of aerial photographs from 1972 and 1993, and on-site photographs (November 1999 to April 2002). The topographic profiles indicated that the erosion period for both the beach and the dunes was June to December. Hurricane Juliette was the responsible for most of the observed erosion. The greatest sediment accumulation occurred between December 2001 and February 2002, associated with the onset of the natural recovery process of the beach-dune system. The photographs revealed that the dunes have lost vegetation cover because of the activities of all-terrain vehicles, which erode paths perpendicular to the dune crests. This in turn allows increased sediment movement, resulting in instability of the dune field system.
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| [29] |
Characteristics of grain size of modern aeolian sand and beach sand in coast of South China. https://doi.org/10.7522/j.issn.1000-694X.2014.00114 URL Magsci [本文引用: 1] 摘要
<p>基于华南海岸沙丘集中分布的闽南、粤东、粤西、海南岛沿岸141个现代沙丘沙和70个海滩沙样品的粒度数据,从粒径组成、粒度参数、粒度参数图和概率累积曲线等方面,分析了华南海岸现代风成沙与海滩沙的粒度差异特点.结果表明:现代沙丘沙较海滩沙细、分选程度变好、正偏相对增多及峰态变窄,但二者的差异并不显著,其概率累积曲线相近且一般通过粒度参数图难以区分,差异程度还呈现出明显的区域性.上述差异主要受华南海岸沙丘发育时间较短、季风气候的风向交替、台风频发、风沙活动空间不足、沙源粗细不同与沙丘规模差别等因素影响.</p>
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| [30] |
华南海岸现代沙丘沙与海滩沙粒度的定量识别 [J]. |
| [10] |
Impact of the winter 2013-2014 series of severe Western Europe storms on a double-barred sandy coast: Beach and dune erosion and megacu spembayments [J].https://doi.org/10.1016/j.geomorph.2015.03.006 URL 摘要
The winter of 2013/2014 was characterized by a striking pattern of temporal and spatial extreme storm wave clustering in Western Europe. The 110-km long Gironde coast, SW France, was exposed to the most energetic wave conditions over the last 1802years. The period was outstanding in terms of the available energy to move sediment and cause large-scale erosion with the 2-month average significant wave height ( H s ) exceeding 3.602m, just below the 0.95 quantile, and 4 distinct 10-year return period storms with H s 02>02902m. These storm waves caused unprecedented beach and dune erosion along the Gironde coast, including severely damaged sea defences at the coastal towns. At the end of the winter, dune erosion scarp height was highly variable alongshore and often exceeded 1002m. Megacusp embayments were observed along the Gironde coast with an average alongshore spacing of 100002m in the south progressively decreasing to 50002m in the north, with an average cross-shore amplitude of 2002m. While beach megacusps were previously observed to systematically couple to the inner bar along the Gironde coast during low- to moderate-energy wave conditions, severe storm-driven megacusp embayments cutting the dune were found to be enforced and coupled to the outer crescentic bar. A detailed inspection of the 150002m-long bimonthly topographic surveys of Truc Vert beach shows that in early January 2014 the outstanding shore-normal incident storm swell ‘Hercules’, with H s and peak wave period T p peaking at 9.602m and 2202s, respectively, triggered the formation of a localized megacusp embayment with the erosion scarp height exceeding 602m in its centre where the dune retreat reached 3002m. The subsequent storms progressively smoothed the megacusp by the end of the winter, mostly through severe erosion of the megacusp horns. Because of the very long period (1602s02<02 T p 02<022302s) storm waves with persistent shore-normal incidence, the well-developed outer crescentic bar observed prior to the winter did not straighten. Instead, the outer-bar three-dimensionality developed further, particularly during ‘Hercules’. Our observations indicate that both the antecedent outer sandbar morphology and storm wave characteristics, including period and angle of incidence, govern patterns of beach and dune erosion along open multiple-barred sandy coasts during severe storms.
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| [11] |
Dune recovery after storm erosion on a high-energy beach: Vougot Beach, Brittany (France) [J].https://doi.org/10.1016/j.geomorph.2011.10.014 URL 摘要
78 Storm dune erosion was generated by extreme water inducing 6 m maximum dune retreat. 78 Initiation of dune recovery was immediate and still ongoing 2.5 years after the storm. 78 Dune regeneration was largely determined by the creation of accommodation space. 78 Dune regeneration led to embryo dunes recovery at an average rate of 4–4.5 cm/month. 78 Sediment supply to the dune was provided by sand eroded to the upper intertidal beach.
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| [12] |
Morphological and sedimentological impacts of Hurricane ivan and immediate poststorm beach recovery along the northwestern Florida barrier-island coasts [J].https://doi.org/10.2112/05-0440.1 URL [本文引用: 1] 摘要
Ivan, a strong Category 4 hurricane (downgraded to a Category 3 at landfall), caused widespread erosion and overwash along the northwestern Florida barrier-island beaches. This study examines the storm impact and short-term poststorm recovery along a 200-km stretch of coast from Fort Walton Beach eastward to St. George Island. One prestorm and three poststorm beach-profile surveys were conducted to quantify the storm-induced morphological changes and poststorm recovery. Forty-six trenches were excavated to study the characteristics and thickness of subaerial storm deposits. Extensive inundation and overwash occurred within 100 km from the storm center at landfall. Significant beach/ dune erosion was measured as far as 300 km east of the storm center. The highest elevation of beach erosion extended considerably above the measured storm-surge level, indicating that storm-wave setup and swash run-up played significant roles in controlling the elevation of beach erosion. A simple empirical formula reproduced the wave setup and swash run-up reasonably well. Beach recovery began immediately after the storm. Within 90 days, the berm crest recovered to its prestorm elevation, although it was now located approximately 15 m landward for nonoverwashed sites and 30 to 40 m for overwashed sites. The steep prestorm foreshore slope was restored from the gentle storm profile within 30 days. An apparent erosional surface was observed along the impacted foredune and backbeach, extending over 300 km eastward from the storm center. This erosional surface represents a net elevation loss ranging from 0.5 to over 2.0 m. A storm layer of up to 50 cm thick was deposited above the erosional surface. Generally, the storm-layer thickness decreases away from the storm center, as well as landward from the high tide line. Local factors such as beach width and orientation, and sediment properties and supply caused variations in the thickness of storm deposit.
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| [13] |
Erosional and depositional characteristics of regional overwash deposits caused by multiple hurricanes [J].https://doi.org/10.1111/j.1365-3091.2006.00848.x URL [本文引用: 1] 摘要
Abstract Regional-scale washover deposits along the Florida Gulf and Atlantic coasts induced by multiple hurricanes in 2004 and 2005 were studied through coring, trenching, ground-penetrating radar imaging, aerial photography, and prestorm and poststorm beach-profile surveys. Erosional and depositional characteristics in different barrier-island sub-environments, including dune field, interior wetland and back-barrier bay were examined. Over the eroded dune fields, the washover deposits are characterized by an extensive horizontal basal erosional surface truncating the old dune deposits and horizontal to slightly landward-dipping stratification. Over the marshes in the barrier-island interior, the washover deposits are characterized by steep tabular bedding, with no erosion at the bottom. Overwash into the back-barrier bay produced the thickest deposits characterized by steep, prograding sigmoidal bedding. No significant erosional feature was observed at the bottom. Washover deposits within the dense interior mangrove swamp demonstrate both normal and reversed graded bedding. The washover deposits caused by hurricanes Frances (2004) and Jeanne (2004) along the southern Florida Atlantic coast barrier islands are substantially different from those along the northern Florida barrier islands caused by Ivan (2004) and Dennis (2005) in terms of regional extension, erosional features and sedimentary structures. These differences are controlled by different overall barrier-island morphology, vegetation type and density, and sediment properties. The homogeneity of sediment along the northern Florida coast makes distinguishing between washover deposits from Ivan and Dennis difficult. In contrast, along the Atlantic coast barrier islands, the two overwash events, as demonstrated by two phases of graded bedding of the bimodal sediments, are easily distinguishable.
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| [14] |
Effect of Hurricane Ivan on coastal dunes of Santa Rosa Barrier Island, Florida: characterized on the basis of pre-and poststorm LIDAR surveys [J].https://doi.org/10.2112/08-1105.1 URL [本文引用: 3] 摘要
Santa Rosa Island, situated along the northwestern Florida coast facing the Gulf of Mexico, is an 85-km-long wavedominated low-lying barrier island with well-developed incipient and established dunes. In this paper, we examine the regional-scale effect on coastal dunes by a strong category 3 hurricane, Ivan, through comparison of pre-and poststorm airborne LIDAR (light detecting and ranging) surveys. On the basis of pre-Ivan LIDAR survey data, the elevation of the berm and back beach is typically 2.0 m above MSL (mean sea level). Incipient dunes range from 2.5 to 10 m above MSL, or 0.5 to 8.0 m above the surrounding beach. The hummocky dunes that developed over relic washover platforms are typically less than 4.0 m above MSL. The densely vegetated, established dune fields are composed of dunes less than 7.0 m high and intradune wetlands lying at less than 1.0 m above MSL. The entire island was severely affected by Ivan, which made landfall about 45 km to the west in September 2004. The landscape was substantially changed by Ivan. Over 70% of the incipient and hummocky dunes were destroyed, and a large portion of the low-lying wetlands was covered by washover. The degree of storm-induced morphology change depends not only on the intensity and duration of the storm but also on the antecedent morphological characteristics of the barrier island. Comparison of pre-and post-Ivan cross-island LIDAR profiles indicates that at most locations, more sand was eroded from the subaerial portion of the barrier island (e. g., beach and dune) than was deposited as washover terraces and lobes. This suggests a net sand loss to the offshore region. Evidence of sand moving alongshore related to the oblique orientation of the dunes was also identified. Under inundation regime, the subaerial sediment deficit could be accounted for by subaqueous sedimentation into the back-barrier bay.
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| [15] |
台风“艾利”对福建沙质海滩影响过程研究 [J].Study on process response of Fujian beach geomorphology to typhoon Aere. |
| [16] |
0418 号台风过境后近岸沉积物粒度特征参数的变化分析 [J].https://doi.org/10.3969/j.issn.1003-6482.2008.02.006 URL 摘要
0418号台风“艾利”过境后，对福建近岸沙质海滩表层沉积物粒度特征参数变化进行分析，结 果表明：海滩沉积物受到扰动，沉积物以粗化为主，分选性减弱，负偏态程度增强，峰态多表现为窄峰态，双峰分布。沉积物平均粒径φ值增大（沉积物变细）的区 带，海滩主要表现为淤积状态；沉积物平均粒径φ值减小（沉积物变粗）的区带，海滩主要表现为冲蚀状态。岬湾岸型海滩沉积物粒度特征参数变化最强烈，沙坝- 泻湖岸型次之，夷直岸型最弱。
Analysison the varying parameters of inshore sediment granularity characteristic after the attacking of 0418 typhoon. https://doi.org/10.3969/j.issn.1003-6482.2008.02.006 URL 摘要
0418号台风“艾利”过境后，对福建近岸沙质海滩表层沉积物粒度特征参数变化进行分析，结 果表明：海滩沉积物受到扰动，沉积物以粗化为主，分选性减弱，负偏态程度增强，峰态多表现为窄峰态，双峰分布。沉积物平均粒径φ值增大（沉积物变细）的区 带，海滩主要表现为淤积状态；沉积物平均粒径φ值减小（沉积物变粗）的区带，海滩主要表现为冲蚀状态。岬湾岸型海滩沉积物粒度特征参数变化最强烈，沙坝- 泻湖岸型次之，夷直岸型最弱。
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The response of three main beach types to tropical storms in South China [J].https://doi.org/10.1016/j.margeo.2010.06.005 URL 摘要
Based on the observational data of 6 storms and 8 different beaches on the coasts of southern China, the paper is concerned with the characteristics of storm-effects on beaches with different morphodynamic types in South China. A dissipative beach is very stable and has a weak response to tropical storms. The storm-induced morphological changes for this type of beach are characterized by erosion at the dune toe and minor changes on the beach face. A low-tide terrace beach has a strong response to storms, with marked changes in the upper profile. A barred beach usually experiences berm erosion, swash bar smoothening, and seaward bar migration during storms. Overwash may occur for the beach without backshore dune or protection. In this paper, backshore changes and the alteration of beach gradient in response to tropical storms are discussed. With taking into account tidal influences, a new morphodynamic parameter ( 蔚 T) is proposed in order to highlight the beach response intensity to storm action. Results show that the inherent morphodynamic properties have significant effects on the beach response to storm. The more dissipative beach has a smaller response intensity and shows a moderate change in beach profile during a storm, while a more reflective beach has a greater response intensity and changes markedly under storm conditions.
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| [18] |
1211号台风对浙江象山皇城海滩剖面的影响分析 [J].
通过对浙江象山皇城海滩地形地貌的现场调查,对比分析了1211 号台风“海葵”登陆象山前后海滩剖面的蚀积变化,探讨了该处海滩对1211号台风“海葵”的响应特征.研究结果表明,在2012年8月台风“海葵”过境期 间,皇城海滩从总体上看,剖面表现为上冲下淤,平面表现为北冲南淤,其后滨沙丘蚀积变化剧烈,海滩沉积物总收支变化不大.皇城海滩不同岸段剖面对台风“海 葵”的响应特征不同,切线段以淤积为主,过渡段、遮蔽段以侵蚀为主,且遮蔽段在三个岸段中变化最小,台风响应强度最弱.台风路径走向、岬湾海滩相对台风的 走向和岬角突出程度是其对台风响应强度的重要影响因素.
Response of sedimentary and geomorphic characteristics to 1211 typhoon on Zhejiang Huangcheng beach.
通过对浙江象山皇城海滩地形地貌的现场调查,对比分析了1211 号台风“海葵”登陆象山前后海滩剖面的蚀积变化,探讨了该处海滩对1211号台风“海葵”的响应特征.研究结果表明,在2012年8月台风“海葵”过境期 间,皇城海滩从总体上看,剖面表现为上冲下淤,平面表现为北冲南淤,其后滨沙丘蚀积变化剧烈,海滩沉积物总收支变化不大.皇城海滩不同岸段剖面对台风“海 葵”的响应特征不同,切线段以淤积为主,过渡段、遮蔽段以侵蚀为主,且遮蔽段在三个岸段中变化最小,台风响应强度最弱.台风路径走向、岬湾海滩相对台风的 走向和岬角突出程度是其对台风响应强度的重要影响因素.
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| [19] |
海坛岛风成沙基本特征及其开发利用意义 [J].
海坛岛是福建省的主要风沙分布区,风成沙同花岗岩、风力并列为岛上的三大自然资源。风成沙是海坛岛风沙土的成土母质,也是高质量的石英砂矿源,但是如果开发利用不当极易酿成沙害。根据风沙地貌类型及其分布特征、风成沙成分特征等,提出了以防风固沙为前提,把风沙地划分为东部沿岸防护林区、内侧农业开发区和西部砂矿开采区三个不同功能区。
The main characteristics and the significance of the exploitation,utilization of aeolian sands in Haitan island, Fujian province.
海坛岛是福建省的主要风沙分布区,风成沙同花岗岩、风力并列为岛上的三大自然资源。风成沙是海坛岛风沙土的成土母质,也是高质量的石英砂矿源,但是如果开发利用不当极易酿成沙害。根据风沙地貌类型及其分布特征、风成沙成分特征等,提出了以防风固沙为前提,把风沙地划分为东部沿岸防护林区、内侧农业开发区和西部砂矿开采区三个不同功能区。
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| [20] |
中国海岸风沙地貌的类型及其分布规律 [J].
通过对我国海岸风沙地貌类型体系及其分布规律的分析总结,提出了一个包括2类、3亚类和13个三级形态类型的中国海岸风沙地貌分类体系,简要介绍了各类海岸风沙地貌的分布,总结了我国海岸风沙地貌的分布特点及其规律。结果表明,我国海岸风沙地貌具有分布范围广泛,规模较小且分布零散,分布地形多样,河口地区分布较集中,区域特征显著,类型与规模差异较大等特点,究其原因是由各地的沙源、气候与地势等海岸风沙地貌形成发育条件的差异造成。
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| [30] |
Quantitative discrimination of grain size of modern coastal aeolian sands and beach sands of South China. |
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