检索结果-南通市图书馆

Control of wind-wave power on morphological shape of salt marsh margins

Water Science and Engineering 2020年第1期13卷 45-56页

作者： Alvise Finotello Marco Marani Luca Carniello Mattia Pivato Marcella Roner Laura Tommasini Andrea D'alpaos Department of Geosciences University of PadovaPadova 35131Italy Department of Environmental Sciences Informatics and StatisticsUniversity of Venice Ca'FoscariVenice 30172Italy center for lagoon hydrodynamics and morphodynamics University of PadovaPadova 35131Italy Department of Civil Environmental and Architectural EngineeringUniversity of PadovaPadova 35131Italy

Salt marshes are among the most common morphological features found in tidal landscapes and provide ecosystem services of primary ecological and economic ***,the continued rise in relative sea level and increasing anthropogenic pressures threaten the sustainability of these *** alarmingly high rates of salt marsh loss observed worldwide,mainly dictated by the lateral erosion of their margins,call for new insights into the mutual feedbacks among physical,biological,and morphological processes that take place at the critical interface between salt marshes and the adjoining tidal *** combined field measurements,remote sensing data,and numerical modeling to investigate the interplays between wind waves and the morphology,ecology,and planform evolution of salt marsh margins in the Venice lagoon of *** results confirm the existence of a positive linear relationship between incoming wave power density and rates of salt marsh lateral *** addition,we show that lateral erosion significantly decreases when halophytic vegetation colonizes the marsh margins,and that different erosion rates in vegetated margins are associated with different *** marsh cliffs and smooth shorelines are expected along rapidly eroding margins,whereas erosion rates are reduced in gently sloped,irregular edges facing shallow tidal flats that are typically exposed to low wind-energy *** highlighting the relationships between the dynamics and functional forms of salt marsh margins,our results represent a critical step to address issues related to conservation and restoration of salt marsh ecosystems,especially in the face of changing environmental forcings.

关键词： Salt marshes Wind waves Lateral erosion morphodynamics Vegetation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effects of the Anthropogenic Activities on the Morphological Evolution of the Modaomen Estuary, Pearl River Delta, China

引用

China Ocean Engineering 2013年第6期27卷 795-808页

作者：贾良文潘顺琪吴超羽 Coastal Ocean Research center Sun Yat-sen University School of Engineering Cardiff University

Owing to the intensive human activities, the Modaomen Estuary has been significantly modified since 1950s, which has resulted in considerable changes of hydrodynamics and morphodynamics in the area. In this paper, the effects of the anthropogenic activities on the hydrodynamics and morphological evolution in the estuary at different stages are systematically assessed based on the detailed bathymetric data and field survey. The results show that the human activities have caused the channelization of the enclosed sea area in the Modamen Estuary;fast seaward movement of the mouth bar with high siltation;expansion of the channel volume due to channel deepening. The paper also highlights the main hydrodynamic changes in the estuary, including the rise of the water level;the distinguishing changes of tidal range before and after the 1990s （decrease and increase respectively）; as well as the increase of the divided flow ratio. It is found that reclamation is the main factor promoting the transition of nature of the estuary from runoff dominant to runoff and wave dominant, and sand mining activities are mainly to strengthen the tidal dynamic and to low the water level. The results provide useful guidance for better planning of the future developments in the estuary and further research in the area.

关键词： Modaomen Estuary anthropogenic activities morphological evolution reclamation sand mining

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

The characteristics of waves around an entrance of a lagoon in South China Sea

引用

Journal of hydrodynamics 2021年第5期33卷 889-900页

作者： Zhi-wen Cai Chun-rong He Xiao-long Liu Wen-wei Chen Ze Sun Jun Ding China Ship Scientific Research center Wuxi 214082China Southern Marine Science and Engineering Guangdong Laboratory(Zhanjiang) 524000China

The characteristics of the waves around a lagoon entrance in South China Sea were observed during the past one and half years based on the wave *** measured results show that the monsoon plays an important *** summer,waves mostly come from the southeast,among which the wave components of non-dimensional periods larger than 0.2 are fetch-trapped *** winter the waves may be divided into two groups,the fetch-trapped waves and the waves from the open *** skewness of the directional distribution functions is within+8 around *** power relationship between the direction spread and kurtosis is also ***,it is found that the waves with the significant wave heights greater than 1.5 m are caused by typhoons or cold *** frequency components of wave energy driven by cold air appear in the high frequency range at first,and change to the lower frequency range *** waves driven by typhoon mostly come from the open sea.

关键词： Reef lagoon cold air typhoon waves South China Sea Introduction

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Geochemical characterization of rare earth elements in sediment profiles from the Oualida lagoon(Morocco)

引用

Acta Geochimica 2023年第6期42卷 1051-1064页

作者： Nezha Mejjad Abdelmourhit Laissaoui Ouafa El Hammoumi Ahmed Fekri Hamid Amsil National center for Energy Sciences and Nuclear Techniques(CNESTEN)RabatMorocco LGAGE Faculty of Sciences Ben M'sikUniversity of Hassan IICasablancaMorocco

The present work assesses the temporal distribution pattern and geochemical changes of rare earth elements and Yttrium, Scandium, Thorium, and Uranium delivery into the Oualidia lagoon. Two sediment cores were retrieved from the Oualidia lagoon and analyzed using neutron activation analysis. The results indicated that heavy rare earth elements are slightly enriched the sediment cores over light rare earth elements. The highest values of REEs were recorded in the top layers of the cores and depleted with depth, suggesting a possible change in factors controlling their accumulation, including mechanical, chemical, and environmental parameters such as weathering intensity, grain size, and Fe-Mn oxides. The sediments display positive Ce anomalies, which are probably related to the submarine weathering process and detrital input. Noting also the variation of hydrodynamics conditions and confinement of the upstream part of the lagoon played a key role in changing the sediment ***, further investigation of REEs origin in the Oualidia lagoon sediment is required to identify their sources,provenances, and the factors controlling their spatial and vertical distributions. However, these results provide baseline data of occurring changes in REEs geochemical composition and constitute a typical study case to understand the link between sedimentary and geochemistry processes in a lagoonal ecosystem.

关键词： Geochemical characterization Rare earth elements Sediment Oualidia lagoon

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Observation and simulation of wind waves near a typical reef lagoon in South China Sea

引用

Journal of hydrodynamics 2021年第1期33卷 24-32页

作者： Ze Sun Dao-lin Xu Xiao-long Liu Hai-cheng Zhang Zhi-wen Cai China Ship Scientific Research center Wuxi 214082China Centre for Marine Technology Hunan UniversityChangsha 410082China Southern Marine Science and Engineering Guangdong Laboratory Zhanjiang 524025China

Due to the inference of the uneven shallow water seabed and the surrounding islands,the wind-generated waves around or in a reef lagoon are rather complicated,and critical to the safety of floating structures deployed near islands or inside a *** paper aims to find a feasible analysis tool for the wave simulations near islands and *** proposed three methods of grid techniques of WAVEWATCH III(WW3)are assessed by using on-site measured data which was collected and accumulated for about 5 years since August 2014 by a wave observation system deployed inside and outside a reef lagoon in South China *** the assessments,the wave statistics including the correlation coefficients,root mean square errors,and their variances are used to quantify the precisions of the simulation results of the significant wave heights,mean wave periods,and peak wave directions at two *** the three methods,the Multi-scale Zone and Multi-scale grid Technique(MZMGT)established on unstructured triangular grids exhibits better results in terms of the accuracy and CPU *** addition,the bimodal feature of wave spectra was observed at both sites of the reef lagoon in different typhoon *** wave characteristics inside the reef lagoon and open sea are also analyzed.

关键词： Wave simulation reef lagoon WAVEWATCH III(WW3) grid methods typhoon waves on-site measurements

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：