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Natural Resources 2017年第5期8卷 353-369页

作者： Mohamed Ali Mohamed lab. of geomorphology Soil Geography and Quaternary Research Department of Geography Humboldt University of Berlin Berlin Germany

The use of remote sensing techniques and subsequent analysis by means of geographical information system (GIS) offers an effective method for monitoring temporal and spatial changes of landscapes. This work studies the urbanization processes and associated threats to natural ecosystems and resources in the metropolitan areas of Berlin and Erlangen-Fürth-Nürnber?Schwabach (EFNS). To compute the land use/cover (LULC) of the study areas, a supervised classification of “maximum likelihood” using Landsat data for the years of 1972, 1985, 1998, 2003, and 2015 is used. Results show that the built-up area is the dominant land use in both regions throughout the study period. This land use has increased at the expense of green and open areas in EFNS and at the expense of agricultural land in Berlin. Likewise, 5% of forest in EFNS is replaced with urban infrastructure. However, the amount of forest in Berlin increased by 3%. While EFNS experienced relatively big changes in its water bodies from 1972 to 1985, changes in water bodies in Berlin were rather slight during the last 40 years. The overall accuracy of our remotely sensed LULC maps was between 88% and 94% in Berlin and between 85.87% and 87.4% for EFNS. The combination of remote sensing and GIS appears to be an indispensable tool for monitoring changes in LULC in urban areas and help improving LU planning to avoid environmental and ecological problems.

关键词： Land Use Change Change Detection Remote Sensing GIS Metropolis City Metropolitan Region

Seasonal changes in coastal dynamics and morphological behavior of the central and southern Changjiang River delta

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Science China Chemistry 2001年第S1期44卷 72-79页

作者：杨世伦赵庆英陈沈良丁平兴 State Key lab.of Estuarine & Coastal Research East China Normal University Shanghai China

Seasonal changes in sea level, tidal range, wind, riverine discharges, nearshore SSC (suspended sediment concentration) and bed-level of intertidal flat at 4 different sites were shown. In addition, the statistical relationships between the dynamics and the behavior of the sediment surface were examined. The average intertidal elevation seems negatively correlated to sea level while positively correlated to nearshore SSC. The effect of wind on seasonal cycle of average intertidal elevation is not evident although wind is an important factor governing short-term erosion/accretion events. The influence of riverine discharges on seasonal cycle of deltaic intertidal flats is masked by other factors. It is concluded that seasonality on mudflats is more complicated than on beaches.

关键词： intertidal flat geomorphology hydrodynamics sedimentation Changjiang River delta.

Circum-Indian Holocene sea-level database:A repository of distinct relative sea-level plots across the Indian Peninsula

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Journal of Palaeogeography 2024年第1期13卷 1-17页

作者： Shradha Menon Pankaj Khanna Santanu Banerjee REEFS lab Department of Earth SciencesIIT GandhinagarPalajGandhinagarGujarat382355India Department of Earth Sciences IIT BombayPowaiMumbai400076India

The Indian Peninsula is one of the most well-studied regions for Holocene sea-level fluctuations in the world, however, standardized relative sea-level datasets are missing. This study provides an archive of sealevel indicators(n = 162, 20 locations) along the western and the eastern sides of the peninsula, that have been used to develop Relative Sea Level(RSL) plots. Each dated sea-level indicator is recalibrated for its elevation based on tidal and tectonic correction, as well as age with reservoir correction, and have been separated into six zones based on coastal geomorphology and number of datasets. The database spans throughout the Holocene and covers sea-level depth/elevations from-45 m to +5 m from mean sea-level(MSL). Approximately 90 % of the dataset range from 8 ka to the present day. The first transgression is highly variable and identified between 8.5-8 ka BP in Gujarat(Zone 1), ~ 5.5 ka BP in Maharashtra(Zone 2), between 8 and 7 ka BP in Tamil Nadu(Zone 4) and between 8 and 7.5 ka BP in the Bengal coasts(Zone 6). No transgression above present sea-level is observed along Andhra Pradesh(Zone 5)(no data for Kerala-Zone 3).Further, Zones 1, 2, 4 and 6 show a strong uplift component(tectonic), whereas Zone 5 exhibits subsidence during the Holocene(Zone 3-insufficient data). Based on these findings, and given the region's coastal topography and tidal components, Zones 6 and 1 will likely undergo the largest coastal inundation, followed by Zones 5, 4, 2, and 3. These insights are critical in planning future coastal inundation measures across the Indian Peninsula.

关键词： Indian ocean Terraces Relative sea level curve Holocene Arabian sea Bay of Bengal

Sustained growth of the largest uninhabited alluvial island in the Changjiang Estuary under the drastic reduction of river discharged sediment

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Science China Earth Sciences 2021年第10期64卷 1687-1697页

作者： Xiaodong ZHANG Rui XIE Daidu FAN Zuosheng YANG Hongmin WANG Chuang WU Yuhan YAO Key lab.of Submarine Geosciences and Prospecting Techniques MOE and College of Marine GeosciencesOcean University of ChinaQingdao 266100China State Key lab.ratory of Marine Geology Tongji UniversityShanghai 200092China

The evolution of the Changjiang Delta is obviously affected by current rapidly rising sea level and drastically declining river discharge,and it is also vital for the sustainable development of Shanghai and the Changjiang River Economic Belt,which represent China’s economic development leader and major national strategic area,*** this paper,the growth pattern of Jiuduansha Island,the largest uninhabited alluvial island in the Changjiang Estuary,is studied in terms of the change in elevation,position and area over the past 50 years through using satellite-derived instantaneous shoreline positions and high/low tide exposure areas based on 497 satellite images from 1974 to 2020;and the influencing factors and future development patterns are further discussed by comparison with other alluvial islands or sandbars in the *** results show that Jiuduansha Island has maintained a rapid or even accelerated area growth rate,although the sediment discharge of the Changjiang River has sharply decreased in recent *** sustained growth is mainly attributed to the existence of the estuarine turbidity maximum zone,coarsening fluvial sediment,onshore sediment replenishment by tide,cone-like geomorphology of Jiuduansha Island,and siltation promotion effect of *** growth rate of the low tide exposure area of Jiuduansha Island increased from 1.9 km^(2)a^(−1) in 1974–1990 to 3.0 km^(2)a^(−1) in 1990–2020,and the growth rate of the high tide exposure area reached as high as 3.7 km^(2)a^(−1) in 1994–*** implementation of the Deep-Water Channel Project has significantly affected the evolution of Jiuduansha Island,including shifting the heads of Shangsha and Zhongxiasha from severe retreat to rapid accretion,and promoting tidal flat progradation seaward of the Jiangyanansha and Zhongxiasha,but restricting the growth of the low tide exposure area of Jiuduansha Island.

关键词： Delta evolution Changjiang Estuary Jiuduansha Island Sandbar and sand island Satellite image

Chronology of the stratum containing the skull of the Dali Man

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Chinese Science Bulletin 2002年第15期47卷 1302-1307页

作者： YIN Gongming ZHAO Hua YIN Jinhui LU Yanchou Institute of Geology China Seismological BureauBeijing 100029China State Key lab.Loess&Quaternary Geology Chinese Academy of ScienceXi’an 710075China Institute of Hydrogeology and Environmental Geology CAGS

The field investigations of geomorphology and Quaternary sediment sequences show that the sediment stratigraphic profile containing the skull of the Homo sapiens Daliensis (Dali Man) at Tianshuigou trench, Jiefang Village (109°44’E, 34°52’N ), Dali County, Shaanxi Province, is composed of the loess-paleosol sequence, 17.3 m thick, in the upper part, and the alluvial silts, fine sands and sandy gravels interbedded, 15.4 m thick, in the lower part. There are the well developed layers L1, S1, L2 and S2 in the loess-paleosol sequence of the profile, which are comparable to those of the Luochuan loess section on the basis of magnetic succeptibility measurements and IRSL dating of the loess samples. An alluvial gravel layer, where the skull of the Dali Man was discovered, is in 13 m beneath the bottom of paleosol S2, implying that, the age of the Dali Man must be older than about 247 kaBP when the paleosol S2 began to be developed. The samples of mammal animal tooth and shell fossils from the gravel layer

关键词： Dali Man stratigraphy chronology.

Facies Architecture Model of the Shimentan Formation Pyroclastic Rocks in the Block-T Units, Xihu Sag, East China Sea Basin, and its Exploration Significance

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Acta Geologica Sinica(English Edition) 2019年第4期93卷 1076-1087页

作者： DAI Xiaojuan TANG Huafeng ZHANG Tao ZHAO Pengjiu XU Chunming KONG Tan ZHAO Tianliang WANG Pujun Collegeof Earth Sciences Jilin UniversityChangchun130061China Key lab.ratory of Mineral Resources Evaluation in Northeast Asia Ministry of Land and ResourcesChangchun 130061China Key lab.for Evolution of Past life and Environment in Northeast Asia Ministry of EducationChangchun 130026China Shanghai Branch of CNOOC Ltd. Shanghai 200030China

A gas field consisting of volcanic reservoir rocks was discovered in the block-T units of the Xihu Sag,East China Sea *** lithology of the volcanic rocks is dominated by tuff and reworked *** lithofacies are dominated by base surge deposits of explosive *** the architecture model of volcanic facies is still uncertain,it has restricted the exploration and development of mineral resources in this *** core and cuttings data,the lithology,lithofacies,geochemistry as well as grain size characteristics of volcanic rocks were *** on these analyses,the volcanic rocks in the well section are divided into three eruptive *** transport direction of each volcanic eruption is analyzed using crystal fragment size *** facies architecture of the block-T units was established based on the reconstruction results of *** results show that the drilling reveals proximal facies(PF)and distal facies(DF)of the volcanic ***,the crater-near crater facies(CNCF)are not *** with the reservoirs of the Songliao Basin,it is shown that the volcanic rocks in the Xihu Sag have good exploration potential;a favorable target area is the CNCF near the contemporaneous fault.

关键词： volcanic rocks Shimentan Formation facies architecture eruptive stage East China Sea Basin

Recent geomorphic changes in the Liaohe Estuary

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Journal of Geographical Sciences 2010年第1期20卷 31-48页

作者： ZHU Longhai WU Jianzheng XU Yongchen HU Rijun WANG Nan Key lab.of Submarine Geosciences and Prospecting Techniques Ministry of Education Ocean University of China Qingdao 266100 China College of Marine Geosciences Ocean University of China Qingdao 266100 Shandong China Engineering Survey and Design ＆ Development Institute Qingdao 266100 Shandong China

This paper mainly analyzes the geomorphological changes of the tidal deposition in the Liaohe Estuary based on the multi-year bathymetric charts in 1990, 1996, 2002 and 2005 and Landsat TM images in 1987, 1994, 2002 and 2005. Evolution of the tidal depositional system during the past 20 years in the Liaohe River was studied on the basis of 50 boreholes drilling and 30 km shallow stratigraphic exploration from 2002 to 2005. The main tidal depositional body of the modern Liaohe River delta is located in the Shuangtaizihe Estuary. The stratum within the depth of 10 m includes tidal bank facies, tidal channel facies and neritic facies with paleo-delta facies underlying them. The sediments of tidal bank facies are mainly composed of sand and silt with siltation load and suspended load of about 50% respectively in proportion. The sediment of tidal channel facies and neritic facies is composed of clayey silt and silty clay which belongs to suspended load. The study area was a small bay between the old Daliaohe River, the old Dalinghe River and the Raoyanghe River complex delta since the Holocene to 1896. Many tidal banks formed and expanded rapidly after the Shuangtaizihe River was excavated by lab.r in 1896. The runoff and sediment discharge have decreased since the construction of brake at the Shuangtaizihe River in *** Shuangtaizihe Estuary is in the state of deposition as a whole whose tidal bank is increasing and expanding south-ward, westward and northward. The maximum expansion speed is 87 to 683 m/a and the mean depositional rate is 0.189 m/a. Erosion occurred in some part of tidal bank with average erosional rate of 0.122 m/a. The tidal channel was filled up with sediment at a migration speed of 48-200 m/a. Geomorphologic changes have happened under the combined influ- ences of runoff, ocean dynamics and human activities. The main source of sediment changes from river sediment to sediment driven by tidal current and longshore current.

关键词： Liaohe River delta geomorphology

The Use of Airborne LiDAR in Assessing Coastal Erosion in the Southeastern USA

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Journal of Geographical Research 2022年第3期5卷 22-40页

作者： David F.Richards IV Adam MMilewski Brian Gregory Water Resources&Remote Sensing lab.WRRS) Department of GeologyUniversity of GeorgiaAthensGA 20602USA Southeast Coast Inventory&Monitoring Network(SECN) Main OfficeSoutheast Coast NetworkAthensGA 30605USA

Changes in sea level along the coastal southeastern United States(U.S.)influence the dynamic coastal *** particular,the Southeast Coastal Network(SECN)of the National Park Service(NPS)has exhibited evidence of fluctuations in sea level which caused coastal *** LiDAR acquired from NOAA for Fort Matanzas National Monument,Fort Pulaski National Monument,Charles Pinckney National Historic Site,and Cape Lookout National Seashore were analyzed to identify changes in both elevation and the spatial volume of unconsolidated sedimentary material in the coastal southeast over *** that exhibited an increase(deposited material)or decrease(eroded material)in elevation were mapped across the study area from 2006 to *** indicate a quasi-cyclic process where unconsolidated sediment distribution and the morphodynamic equilibrium changes with *** coastal zones are steadily oscillating between the process of erosion and deposition affecting the coastal geomorphological *** use of LiDAR for evaluating coastal sustainability and resiliency due to this environmental phenomenon is clear.

关键词： Coastal Erosion LiDAR Elevation Volumetric change geomorphology Sea level