大鹏湾岬湾型海滩季节性变化特征及原因分析——以官湖海滩为例     

刘星璐  徐昇  罗小峰  张功瑾  丁磊  路川藤  丁佩 《海洋工程》2022,40(4):44-52

随着全球海平面的上升及极端气象的频发,全球海滩总体呈现出一定的退化现象,海滩保护成为海岸带生态修复的焦点问题之一。我国华南地区岬湾型海滩分布广泛,以深圳市大鹏湾官湖海滩为代表,基于2020—2021年实测海滩剖面高程数据,分析岬湾型海滩季节性变化特征。研究表明,官湖海滩剖面坡度夏秋缓冬春陡,夏秋侵蚀冬春淤积;海滩沉积物粒径季节性变化不明显。海滩剖面形态受风浪、平均潮位的季节性变化控制,以夏秋季为例,平均潮位逐渐升高,南向波浪强度较大,在二者的共同作用下,海滩后滨侵蚀明显,泥沙离岸输运,并在前滨淤积。补沙方案宜在夏秋季进行,且重点区域为官湖海滩东侧与观海湾海滩,防御方案应主要削弱南向波浪。  相似文献   

渤海表层悬沙的时空分布特征及其动力成因          下载免费PDF全文

庞重光  李坤  于炜 《海洋科学进展》2014,32(4)

针对目前渤海整个海域悬浮泥沙分布全貌的研究不充分。根据2000—2004年渤海表层悬浮泥沙分布特征选取7个典型海区,通过利用长时间序列悬沙质量浓度和风场遥感反演资料,在分析悬沙质量浓度与局地风速、物质来源等关系的基础上,定量研究风浪和潮流共同作用下、随季节显著变化的沉积物再悬浮过程,从而揭示整个渤海海域代表性海区悬沙质量浓度时空分布的动力成因。渤海不同海区表层悬沙质量浓度绝对值差别很大,多年平均最高质量浓度在20~450mg/L变化,高质量浓度集中在近岸河口区及其邻近海域,如黄河口和辽河口地区,低质量浓度区位于渤海中部、渤海海峡以及秦皇岛外海(属于近岸海域却质量浓度常年偏低的特殊海区)。渤海表层悬沙质量浓度具有明显的季节变化特征,风场的季节变化是主要影响因子,各代表性海区悬沙质量浓度与风速之间具有显著正相关关系。悬沙质量浓度与风速之间存在一定时间段的滞后相关。沉积物再悬浮的定量研究表明,除渤海海峡外,渤海其它典型海区表层悬沙质量浓度及其季节变化,均与各自海区风浪和潮流共同作用产生的最大底流速及其季节变化相对应。在渤海,底层沉积物再悬浮的季节变化是影响悬沙质量浓度季节变化最关键的动力过程。  相似文献   

Optical closure of parameterized bio-optical relationships     

贺双颜  贺明霞 《中国海洋湖沼学报》2014,32(2):480-489

An optical closure study on bio-optical relationships was carried out using radiative transfer model matrix operator method developed by Freie Universitt Berlin.As a case study,the optical closure of bio-optical relationships empirically parameterized with in situ data for the East China Sea was examined.Remote-sensing refl ectance(R rs)was computed from the inherent optical properties predicted by these biooptical relationships and compared with published in situ data.It was found that the simulated R rs was overestimated for turbid water.To achieve optical closure,bio-optical relationships for absorption and scattering coeffi cients for suspended particulate matter were adjusted.Furthermore,the results show that the Fournier and Forand phase functions obtained from the adjusted relationships perform better than the Petzold phase function.Therefore,before bio-optical relationships are used for a local sea area,the optical closure should be examined.  相似文献   

The seasonal foot printing mechanism of spring Arctic sea ice in the Bergen climate models     

GUO Dong  GAO Yongqi  GONG Daoyi 《极地研究(英文版)》2014,(4)

The influence of spring Arctic sea ice variability on the Pacific Decadal Oscillation(PDO) like sea surface temperature(SST) variability is established and investigated using an Atmosphere Ocean General Circulation Model(AOGCM) of the Bergen Climate Model version 2(BCM2). The spring Arctic sea ice variability affects the mid-latitudes and tropics through the propagation of the anomalous Eliassen-Palm(E-P) flux from the polar region to mid- and low-latitudes during boreal spring. The pathway includes anomalous upward wave activity, which propagates to the high troposphere from near the surface of the polar region, turns southward between 500 h Pa and 200 h Pa and extends downward between 50°N and 70°N, influencing the near surface atmospheric circulation. The alteration of the near surface atmospheric circulation then causes anomalous surface ocean circulation. These circulation changes consequently leads to the SST anomalies in the North Pacific which may persist until the following summer, named seasonal "foot printing" mechanism(SFPM).  相似文献   

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张锐  刘志广  占伟  梁洪宝  师宏波  王友  董彦知  李瑜 《大地测量与地球动力学》2014,34(2):31-35

????????????????GNSS??????????????о???????????1???????????????????仯?????????????仯????????仯???????仯?й??2???????????????????????????????????????????????仯????????С??3?????3.5 m????????????????????????????????????????  相似文献   

Seasonal Variations in Phytoplankton Community Structure in the Sanggou,Ailian, and Lidao Bays     

YUAN Mingli  ;ZHANG Cuixia  ;JIANG Zengjie  ;GUO Shujin  ;SUN Jun 《青岛海洋大学学报(英文版)》2014,(6):1012-1024

The seasonal variations in phytoplankton community structure were investigated for the Sanggou Bay （SGB） and the adjacent Ailian Bay （ALB） and Lidao Bay （LDB） in Shandong Peninsula,eastern China.The species composition and cell abundance of phytoplankton in the bay waters in spring （April 2011）,summer （August 2011）,autumn （October 2011）,and winter （January 2012） were examined using the Uterm6hl method.A total of 80 taxa of phytoplankton that belong to 39 genera of 3 phyla were identified.These included 64 species of 30 genera in the Phylum Bacillariophyta,13 species of 8 genera in the Phylum Dinophyta,and 3 species of 1 genus in the Phylum Chrysophyta.During the four seasons,the number of phytoplankton species （43） was the highest in spring,followed by summer and autumn （40）,and the lowest number ofphytoplankton species （35） was found in winter.Diatoms,especially Paralia sulcata （Ehrenberg） Cleve and Coscinodiscus oculus-iridis Ehrenberg,were predominant in the phytoplankton community throughout the study period,whereas the dominance of dinoflagellate appeared in summer only.The maximum cell abundance of phytoplankton was detected in summer （average 8.08 × 103 cells L-1） whereas their minimum abundance was found in autumn （average 2.60 x 103 cellsL-1）.The phytoplankton abundance was generally higher in the outer bay than in the inner bay in spring and autumn.In summer,the phytoplankton cells were mainly concentrated in the south of inner SGB,with peak abundance observed along the western coast.In winter,the distribution of phytoplankton cells showed 3 patches,with peak abundance along the western coast as well.On seasonal average,the Shannon-Wiener diversity indices of phytoplankton community ranged from 1.17 to 1.78 （autumn 〉 summer 〉 spring 〉 winter）,and the Pielou＇s evenness indices of phytoplankton ranged from 0.45 to 0.65 （autumn 〉 spring 〉 summer〉 winter）.According to the results of canonical correspondence analysis,phosphate level w  相似文献   

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����  ������  ������  ����  ��־�� 《大地测量与地球动力学》2014,34(6):50-54

????GRACE?????????????????н???????????????139????????????????????????????仯??ο???????????ж?????????????????????????80%????????????????????????????????????λ???????С???????1 mm???????????????????????????????????????仯???????λ????????????С1.4??1.6 mm??  相似文献   

Modeling seasonal variations of subsurface chlorophyll maximum in South China Sea   总被引：1，自引：0，他引：1  

Xiang Gong  Jie Shi  Huiwang Gao 《中国海洋大学学报(英文版)》2014,13(4):561-571

In the South China Sea(SCS), the subsurface chlorophyll maximum(SCM) is frequently observed while the mechanisms of SCM occurrence have not been well understood. In this study, a 1-D physical-biochemical coupled model was used to study the seasonal variations of vertical profiles of chlorophyll-a(Chl-a) in the SCS. Three parameters(i.e., SCM layer(SCML) depth, thickness, and intensity) were defined to characterize the vertical distribution of Chl-a in SCML and were obtained by fitting the vertical profile of Chl-a in the subsurface layer using a Gaussian function. The seasonal variations of SCMs are reproduced reasonably well compared to the observations. The annual averages of SCML depth, thickness, and intensity are 75 ± 10 m, 31 ± 6.7 m, and 0.37 ± 0.11 mg m-3, respectively. A thick, close to surface SCML together with a higher intensity occurs during the northeastern monsoon. Both the SCML thickness and intensity are sensitive to the changes of surface wind speed in winter and summer, but the surface wind speed exerts a minor influence on the SCML depth; for example, double strengthening of the southwestern monsoon in summer can lead to the thickening of SCML by 46%, the intensity decreasing by 30%, and the shoaling by 6%. This is because part of nutrients are pumped from the upper nutricline to the surface mixed layer by strong vertical mixing. Increasing initial nutrient concentrations by two times will increase the intensity of SCML by over 80% in winter and spring. The sensitivity analysis indicates that light attenuation is critical to the three parameters of SCM. Decreasing background light attenuation by 20% extends the euphotic zone, makes SCML deeper(~20%) and thicker(12% – 41%), and increases the intensity by over 16%. Overall, the depth of SCML is mainly controlled by light attenuation, and the SCML thickness and intensity are closely associated with wind and initial nitrate concentration in the SCS.  相似文献   

台湾东北部黑潮次表层水入侵的季节变化规律   总被引：5，自引：1，他引：4  

赵瑞祥  刘志亮 《海洋学报》2014,36(1):20-27

台湾东北部,黑潮次表层水常年入侵东海陆架。但是黑潮次表层水入侵的季节变化规律,尚存在很多不明之处。本文基于2009至2011年间东海4个航次的CTD实测数据,研究了黑潮次表层水入侵东海过程的季节变化规律,发现:黑潮次表层水入侵在春末夏初开始加强,夏季最强,秋季开始减弱,冬季最弱。入侵的黑潮次表层水起源深度也随季节变化有所不同。另外,结果还表明黑潮次表层水入侵存在明显的短期变动。  相似文献   

东海西部陆架海域水团的季节特征分析   总被引：3，自引：1，他引：2  

张启龙  刘洪伟  秦思思  杨德周  刘志亮 《海洋学报(英文版)》2014,33(11):64-74

On the basis of the CTD data and the modeling results in the winter and summer of 2009, the seasonal characteristics of the water masses in the western East China Sea shelf area were analyzed using a cluster analysis method. The results show that the distributions and temperature-salinity characteristics of the water masses in the study area are of distinct seasonal difference. In the western East China Sea shelf area, there are three water masses during winter, i.e., continental coastal water（CCW）, Taiwan Warm Current surface water（TWCSW） and Yellow Sea mixing water（YSMW）, but four ones during summer, i.e., the CCW, the TWCSW, Taiwan Warm Current deep water（TWCDW） and the YSMW. Of all, the CCW, the TWCSW and the TWCDW are all dominant water masses. The CCW, primarily characterized by a low salinity, has lower temperature, higher salinity and smaller spatial extent in winter than in summer. The TWCSW is warmer, fresher and smaller in summer than in winter, and it originates mostly from the Kuroshio surface water（KSW） northeast of Taiwan, China and less from the Taiwan Strait water during winter, but it consists of the strait water and the KSW during summer. The TWCDW is characterized by a low temperature and a high salinity, and originates completely in the Kuroshio subsurface water northeast of Taiwan.  相似文献