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Numerical simulation of benzene transport in shoreline groundwater affected by tides under different conditions

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Frontiers of Environmental Science & Engineering 2022年第5期16卷 83-95页

作者： Mahsa Kheirandish Chunjiang An Zhi Chen Xiaolong Geng Michel Boufadel Department of Building Civil and Environmental EngineeringConcordia UniversityMontrealQC H3G 1M8Canada Center for Natural Resources Department of Civil and Environmental EngineeringNew Jersey Institute of TechnologyNewark NJ 07102USA

The release and transport of benzene in coastal aquifers were investigated in the present study.Numerical simulations were implemented using the SEAM3D,coupled with GMS,to study the behavior of benzene in the subsurface of tidally influenced beaches.The transport and fate of the benzene plume were simulated,considering advection,dispersion,sorption,biodegradation,and dissolution on the beach.Different tide amplitudes,aquifer characteristics,and pollutant release locations were studied.It was found that the tide amplitude,hydraulic conductivity,and longitudinal dispersivity were the primary factors affecting the fate and transport of benzene.The tidal amplitude influenced the transport speed and percentage of biodegradation of benzene plume in the beach.A high tidal range reduced the spreading area and enhanced the rate of benzene biodegradation.Hydraulic conductivity had an impact on plume residence time and the percentage of contaminant biodegradation.Lower hydraulic conductivity induced longer residence time in each beach portion and a higher percentage of biodegradation on the beach.The plume dispersed and the concentration decreased due to high longitudinal dispersivity.The results can be used to support future risk assessment and management for the shorelines impacted by spill and leaking accidents.Modeling the heterogeneous beach aquifer subjected to tides can also be further explored in the future study.

关键词： Numerical simulation Benzene Transport and fate shoreline Groundwater Tide

A novel mathematical morphology based algorithm for shoreline extraction from satellite images

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Geo-Spatial Information Science 2017年第4期20卷 345-352页

作者： C.A.Rishikeshan H.Ramesh National Institute of Technology Karnataka Surathkal India

shoreline extraction is fundamental and inevitable for several studies.Ascertaining the precise spatial location of the shoreline is crucial.Recently,the need for using remote sensing data to accomplish the complex task of automatic extraction of features,such as shoreline,has considerably increased.Automated feature extraction can drastically minimize the time and cost of data acquisition and database updating.Effective and fast approaches are essential to monitor coastline retreat and update shoreline maps.Here,we present a flexible mathematical morphology-driven approach for shoreline extraction algorithm from satellite imageries.The salient features of this work are the preservation of actual size and shape of the shorelines,run-time structuring element definition,semi-automation,faster processing,and single band adaptability.The proposed approach is tested with various sensor-driven images with low to high resolutions.Accuracy of the developed methodology has been assessed with manually prepared ground truths of the study area and compared with an existing shoreline classification approach.The proposed approach is found successful in shoreline extraction from the wide variety of satellite images based on the results drawn from visual and quantitative assessments.

关键词： Feature extraction shoreline detection satellite image processing remote sensing mathematical morphology

Long-Time shoreline Monitoring of the Vellar Estuarine Complex,Southeast Coast of India:Using Multispectral Satellite Data

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Journal of Earth Science 2012年第6期23卷 900-907页

作者： L Senthilnathan E P Nobi T Thangaradjou L Kannan Centre of Advanced Study in Marine Biology Faculty of Marine SciencesAnnamalai UniversityParangipettai-608502TamilnaduIndia

The present study was carried out to track the path of Vellar estuary over a period of 38 years （1970-2008） and also to detect the impact of tsunami on estuarine complex of the Vellar estuary. Visual interpretation techniques were employed by using muitispectral data of Landsat TM （1991） and IRS-P6 LISS III （2004, 2006, and 2008） to delineate shoreline changes in the VeUar estuarine complex. Results clearly revealed the changes that occurred along the estuarine path over the period, and severe erosion was noticed in the seaward side of the MGR Thittu and accretion, along the estuarine mouth. It is also visible that there is clear river path shift in the river course. Although the sandbar formation was seen with only little morphologic modification up to 2004, the Indian Ocean tsunami that struck this coast （26 December, 2004） distorted the sandbar of the Vellar estuarine mouth; however, the 2006 satel- lite images confirmed that the sandbar was formed again to its original structure as that of before the tsunami.

关键词： estuary geomorphology IRS-P6 LISS III shoreline tsunami India.

1985-2015 年渤海海岸线和围填海的时空变迁研究（英文）

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Journal of Geographical Sciences 2019年第12期29卷 2031-2046页

作者：丁小松单秀娟陈云龙金显仕 MUHAMMED Forruq Rahman College of Marine Sciences Shanghai Ocean UniversityShanghai 201306China Laboratory for Marine Fisheries Scienee and Food Production Processes Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237ShandongChina Key Laboratory of Sustainable Development of Marine Fisheries Ministry of Agriculture and Rural AffairsShandong Provincial Key Laboratory of Fishery Resources and Eco-environmentYellow Sea Fisheries Research InstituteChinese Academy of Fishery SciencesQingdao 266071ShandongChina College of Fisheries Ocean University of ChinaQingdao 266003ShandongChina

Extraction and analysis of the shoreline and land reclamation patterns are important for studies on topics such as the dynamics of coastal wetland ecological environments,transportation and exchange of material energy in coastal regions,and recruitment of fishery resources.Spatial-temporal variations in the shoreline and land reclamation in the Bohai Sea were analyzed based on 49 Landsat images of 7 periods from 1985 to 2015.The following conclusions were drawn.(1)The extracted shoreline data based on visual interpretation had high precision,and the shoreline extraction errors could be controlled within the theoretical range.(2)Over the past 30 years,the shoreline of the Bohai Sea has exhibited an average rate of change of 188.47 m/a and an average accretion distance of 3.55×10^3 m toward the sea.The fastest rate of shoreline change occurred in Laizhou Bay(134.78 m/a),followed by Bohai Bay(128.20 m/a)and Liaodong Bay(61.69 m/a).(3)The average rate of reclamation was 3.25×10^4 ha/a in the Bohai Sea,where the total area of aquaculture land,unused land,and salt land exceeded 60%of the total reclamation area.(4)The geometric shape of the bay became increasingly complicated from year to year,and the geometric center of gravity of the bay moved rapidly toward the sea.In addition,the area of the bay showed a significant decreasing trend.Therefore,to protect the function and structure of the ecosystem in coastal regions,we must control the scale and rate of land reclamation in the future.

关键词： shoreline change land reclamation shape index of the bay Bohai Sea China

Paleo-shoreline changes in moraine dammed lake Khagiin Khar, Khentey Mountains, Central Mongolia

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Journal of Mountain Science 2019年第6期16卷 1215-1230页

作者： OH Jeong-Sik SEONG Yeong Bae HONG Seongchan YU Byung Yong Department of Geography Education Korea UniversityAnam-Ro 145Seongbuk-GuSeoul 02841Korea AMS Laboratory Advanced Analysis CenterKorea Institute of Science and TechnologySeoul 02791Korea

The formation and evolution of glacier moraine-dammed lakes are closely related to past glacier expansion and retreat. Geomorphic markers such as lacustrine terraces and beach ridges observed in these lakes provide important evidence for regional paleoenvironment reconstruction. We document the magnitude of paleo-shoreline fluctuations and timings of highstands of lake water by using cosmogenic 10Be surface exposure dating and optically stimulated luminescence(OSL) dating on samples collected from lacustrine sediment and bedrock strath in Lake Khagiin Khar. The lake was initially impounded by glacier moraine at the Global Last Glacial maximum(gLGM;21–19 ka), and the lake reached its maximum paleo-shoreline level of 1840 m at sea level(a.s.l.). At that time, the stored lake water amount was up to seven times greater and the surface area was three times larger than the present values. The paleolake experienced higher shoreline levels at 1832, 1822, and 1817 m a.s.l. and reached the present lake level after 0.4 ka. We interpret that decrease in the paleolake level was caused by spillover. The increase in melt water after the gLGM and the Late Glacial exceeded the storage threshold of the lake, and the paleolake water overflowed across the lowest drainage divides. The lake spilled over across the lowest bedrock ridge at 15.9 ± 0.6 ka, and the outlet was incised since that time at a rate of 3.72 ± 0.15 mm/yr. The initial stream of the Khiidiin Pass River was disturbed by LGM moraine damming and was rerouted into the present course running through moraine after the spillover at 15.9 ± 0.6 ka.

关键词： Moraine-dammed lake Lake Khagiin Khar shoreline Spillover 10Be exposure dating

shoreline Change Analysis in Demak, Indonesia

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Journal of Environmental Protection 2017年第8期8卷 940-955页

作者： Komariah Ervita Muh Aris Marfai Faculty of Geography Universitas Gadjah Mada Yogyakarta Indonesia

Demak Regency is located in Central Java Province Indonesia bordering the Java Sea. Intense activities in the coastal area of Demak have caused changes in the shoreline. This paper aimed to determine the shoreline change for 25 years and to identify the major factors that influenced those changes in the coastal area of Demak. A shoreline change analysis was conducted based on Multitemporal Landsat satellite imagery with sensors of Thematic Mapper (TM), Enhanced Thematic Mapper plus (ETM+), and Operational Land Imager (OLI). This study used the data from multitemporal Landsat imagery of year 1990, 1994, 1999, 2002, 2008, 2011, and 2015. Identification of the shoreline was performed through band ratio, histogram threshold, and composite band 457 methods. An erosion and accretion analysis has been done using the wind data via the processing of Wind Rose Plot (WRPLOT), wave prediction using Sverdrup Munk Bretschneider (SMB) method, tide data processing to know the value of Mean High Water Level (MHWL), Mean Sea Level (MSL), Mean Low Water Level (MLWL), and Lowest Low Water Level (LLWL), as well as currents data processing that has been implemented to achieve the goal. The research results showed that the shoreline change in Demak Regency was quite distinct compared to several previous years due to erosion and accretion processes. The greatest shoreline change happened in Sayung District and Wedung District. Sayung District was likely to experience erosion process while Wedung District tended to show accretion process. Several physical factors that became the major influence on these changes were the wind, waves, currents, and tides.

关键词： shoreline Dynamics Erosion Accretion Demak Regency Indonesia

Trends of shoreline Position: An Approach to Future Prediction for Balasore shoreline, Odisha, India

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Open Journal of Marine Science 2015年第1期5卷 13-25页

作者： Nilay Kanti Barman Soumendu Chatterjee Ansar Khan Department of Geography and Environment Management Vidyasagar University Midnapore India Department of Geography Presidency University Kolkata India

The present study aims to analyze the shift in shoreline due to coastal processes and formulate available for best estimate of future shoreline positions based on precedent shorelines. Information on rates and trends of shoreline change can be used to improve the understanding of the underlying causes and potential effects of coastal erosion which can support informed coastal management decisions. In this paper, researchers go over the changes in the recent positions of the shoreline of the Balasore coast for the 38 years from 1975 through 2013. The study area includes the Balasore coastal region from Rasalpur to Udaypur together with Chandipur, Choumukh, Chandrabali as well as Bichitrapur. Transects wise shoreline data base were developed for approximately 67 kilometers of shoreline and erosional/accretional scenario has also been analysed by delineating the shoreline from Landsat imageries of 1975, 1980, 1990, 1995, 2000, 2005, 2010 and 2013. A simple Linear Regression Model and End Point Rate (EPR) have been adopted to take out the rate of change of shoreline and its future positions, based on empirical observations at 67 transects along the Balasore coast. It is found that the north eastern part of Balasore coast in the vicinity of Subarnarekha estuary and Chandrabali beach undergo high rates of shore line shift. The shoreline data were integrated for long- (about 17 years) and short-term (about 7 years) shift rates analysis to comprehend the shoreline change and prediction. For the prediction of future shoreline, the model has been validated with the present shoreline position (2013). The rate of shoreline movement calculated from the fixed base line to shoreline position of 1975, 1980, 1990, 1995, 2000, 2005 and 2010 and based on this, the estimated shoreline of 2013 was calculated. The estimated shoreline was compared with the actual shoreline delineated from satellite imagery of 2013. The model error or positional shift at each sample point is observed. The positional error varies from??4.82 m to 212.41 m

关键词： Linear Regression Model End Point Rate Root Mean Square Error shoreline Change shoreline Prediction

Analysis of the Mamaia Bay shoreline Retreat with Hard and Soft Protection Works

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Journal of Marine Science 2019年第1期1卷 7-17页

作者： Catalin Anton Carmen Gasparotti Iulia Alina Anton Eugen Rusu "Dunarea de Jos"University Galati -Romania 47 Domneasca Str.800008GalatiRomania "Dunarea de Jos"University Galati -Romania Department of Naval Architecture47 Domneasca Str.800008GalatiRomania Maritime University of Constanta -Romania 104 Mircea cel Batran str.900663Constanta "Dunarea de Jos"University Galati -Romania Department of Mechanical Engineering47 Domneasca Str800008GalatiRomania

Integrated Coastal Zone Management is a complex concept that involves various economic, social and environmental factors. There are often conflicting approaches to these factors. Furthermore, when it is decided to implement structural works in the coastal area, it must be taken into account the particularity of the area, the way in which it is developed and the type of work to be done. The Gulf of Mamaia in the Romanian Black Sea coast is the target of structural changes through the implementation of an extensive coastal rehabilitation program. The works made are of “hard” type and aim to change the shore line configuration. From this perspective, the target of the present paper is to make an analysis between the type of work that is being carried out and another kind of "soft" work aiming especially to favor the ecological reconstruction of the area and the approach of an environmentally friendly concept. Thus, we propose to analyze the two types of works with a view to apply the Bruun rule in order to mitigate the effect of the increase of the sea level and to prevent the shoreline retreat.

关键词： Coastal zone management Romanian coast Mamaia Bay Black Sea shoreline Hard and soft works

Erosion hotspot identified along the sandy coast of Shanwei: characteristics and origin

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Acta Oceanologica Sinica 2023年第7期42卷 91-102页

作者： Jitao Yu Yuanting Ding Lin Zhang Pei Liu Renfu Fan Hainan Academy of Ocean and Fisheries Sciences Haikou 571126China Yazhou Bay Innovation Institute Hainan Tropical Ocean UniversitySanya 572025China School of Geography and Environmental Sciences Hainan Normal UniversityHaikou 571158China

Based on the measured beach profile data of Sanzhou Bay from 2015 to 2019,an erosion hotspot was identified along the Shanwei coastline of eastern Guangdong,where the maximum retreat distance of the shoreline exceeded 80 m and the erosion rate was more than 20 m/a.To determine the time at which the erosion hotspot started and the potential causes of its formation,this study used 63 Landsat satellite images from 1986 to 2019 to construct a time series of shoreline positions over the past 30 years by extracting their high-tide shorelines.Next,the M-K trend test method was introduced to evaluate the non-linear shoreline behavior based on the single-transect method.The results showed that the time of approximately 2013 marked the start of the erosion hotspot,the erosion hotspot was characterized by erosion rates of more than 2 m/a(a maximum rate of 31.6 m/a),and the affected shoreline more than 4.3 km from 2013 to 2019.Furthermore,this erosion hotspot was proved to be caused by artificial sand mining in the nearshore zone,which destroyed the original beach’s morphodynamic equilibrium.With the aid of storm events,soil cliffs composed of loose sediment on the backshore were sacrificed to achieve a new equilibrium,resulting in an extremely significant retreat parallel to the coast on the west side of the study area,which reflects the combined effect of human and natural processes.This study provides a concrete example of the rapid response of shorelines to artificial sand mining activities,and the associated finding is a stark warning about the cautious development and utilization of coastal zones and the strict regulation of human activities.

关键词： erosion hotspot shoreline non-linear behavior artificial sand mining beach morphodynamic equilibrium Landsat images