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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 delta.c 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.

Prediction and prevention of the impacts of sea level rise on the Yangtze River delta.and its adjacent areas

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Science China Earth Sciences 2000年第4期43卷 412-422页

作者：施雅风朱季文谢志仁季子修蒋自巽杨桂山 Nanjing Institute of Geography & Limnology Chinese Academy of Sciences Nanjing 210008 China Geographical College Nanjing Normal University Nanjing 210024 China

The Yangtze River delta.region is characterized by high density of population and rapidly developing economy. There are low lying coastal plain and delta.c plain in this region. Thus, the study area could be highly vulnerable to accelerated sea level rise caused by global warming. This paper deals with the scenarios of the relative sea level rise in the early half period of the 21st century in the study area. The authors suggested that relative sea level would rise 25–50 cm by the year 2050 in the study area, of which the magnitude of relative sea level rise in the Yangtze River delta.would double the perspective worldwide average. The impacts of sea level rise include: (i) exacerbation of coastline recession in several sections and vertical erosion of tidal flat, and increase in length of eroding coastline; (ii) decrease in area of tidal flat and coastal wetland due to erosion and inundation; (iii) increase in frequency and intensity of storm surge, which would threaten the coastal protection works; (iv) reduction of drainage capacity due to backwater effect in the Lixiahe lowland and the eastern lowland of Taihu Lake region, and exacerbation of flood and waterlogging disasters; and (v) increase in salt water intrusion into the Yangtze Estuary. Comprehensive evaluation of sea level rise impacts shows that the Yangtze River delta.and eastern lowland of Taihu Lake region, especially Shanghai Municipality, belong in the district in the extreme risk category and the next is the northern bank of Hangzhou Bay, the third is the abandoned Yellow River delta. and the district at low risk includes the central part of north Jiangsu coastal plain and Lixiahe lowland.

关键词： sea level rise impact prevention Yangtze River delta.

m-Quarterphenyl detected in the aerosols of Pearl River delta.and preliminary study on its environmental significance

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Chinese Science Bulletin 1997年第13期42卷 1107-1110页

作者： Cheng, Y Fu, JM Shen, GY Min, YS Le, SC Chan, LY Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Guangdong State Kay Lab. Environ. P. Chinese Academy of Sciences Guangzhou 510640 China Department of Civil Engineer Hongkong University Hong Kong

m-QUARTERPHENYL, also nominated as 5′-phenyl-1, 1′: 3′1″-terphenyl, is one of the four-ringpolycyclic aromatic hydrocarbons （PAHs） with its four rings meta-linked together with C—Cbonds. Its molecular formula is C18H24 and its molecular weight 306. m-Quarterphenyl and other kinds of quarterphenyls as well as terphenyls have been de-tected in aerosols by Beemaert by use of GC-MS. Tong, and Karasek and Tong ana-

关键词： m-quarterphenyl aerosol environmental significance Pearl River delta.

Magnetic fabric characteristics of late Quaternary strata in Shanghai area

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Chinese Science Bulletin 1998年第18期43卷 1579-1583页

作者： Daidu Fan Qingqiang Cheng Youzi Cong Congxian Li Tongji Univ State Educ Commiss Lab Marine Geol Shanghai 200092 Peoples R China State Oceanog Adm Inst Oceanog 1 Qingdao 266003 Peoples R China

The result of measurements and analyses on magnetic fabrics data for the late Quaternary core at Caoyangxincun in Shanghai shows that abrupt changes of magnetic fabric curves coincide with the boundaries between the marine strata and underlying stiff clay. Littoral, neritic, subtidal and tidal flat facies in the marine strata have distinct magnetic fabric characteristics. The curves of the parameters, K, P, L, q, display clear boundaries between various facies, which could serve as a new method for the stratigraphic subdivision and correlation.

关键词： Magnetic fabric stratigraphic subdivision and correlation Changjiang delta.

Stage characteristics for the development of late Quaternary paleosols in the Yangtze delta.area

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Chinese Science Bulletin 1999年第9期44卷 857-860页

作者： CHEN Qingqiang and LI CongxianLaboratory of Marine Geology , Tongji University , Shanghai 200092, China Guangzhou Institute of Geochemistry , Chinese Academy of Sciences , Guangzhou 510640, China Laboratory of Marine Geology Tongji University Shanghai China Guangzhou Institue of Geochemistry Chinese Academy of Sciences Guangzhou China

The late Quaternary paleosols in the Yangtze delta.area developed in the period of 25 000—12 000 aBP. Phytolith ratios (value A) of contents of fan, square and rectangle types indicaring the warm and humid climate to those of bar, hat and point types indicating cold and dry climates decrease upwards overall on profiles of the paleosols, suggesting that the climates turned from warm and humid to cold and dry. So, the paleosols developed mainly during the regression before the last glacial maximum. Changes of value A indicate no trend of warming, suggesting that the transgression was rapid after the last glacial maximum. The development of the paleosols exhibited obvious stages, which were controlled remarkably by transgression and regression: Ⅰ. Period of alternation of deposition and pedogenesis, which was from the occurrence of regresson before the last glacial maximum to the time when sea levels fell close to the lowest;Ⅱ. Exposure period with continual pedogenesis, which was terminated when the

关键词： paleosol phytolith development processes late Quaternary Yangtze delta.

Optimizing Decentralization of Management andExploitation of Irrigation Works in Quan Lo-Phung HiepRegion, Mekong River delta

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Journal of Agricultural Science and Technology(A) 2016年第5期6卷 314-323页

作者： Nguyen Due Viet Nguyen Van Tinh Nguyen Tung Phong Dang Ngoc Hanh Directorate of Water Resources Ministry of Agriculture and Rural Development (MARD) Hanoi 100000 Vietnam Vietnam Academy for Water Resources (VA WR) Hanoi 100000 Vietnam

In Vietnam as well as many countries which apply the irrigated agriculture over the world, the process of promoting thesocialization trend in irrigation for the basic irrigation organizations, of which the main factor is water users, is very important. Thispaper aimed to optimize the decentralization of management and exploitation of irrigation works for water users, organizations inQuan Lo-Phung Hiep irrigation system of Mekong River delta. The research has implemented a survey on 384 water users alongfour canals of level 2 of Quan Lo-Phung Hiep irrigation system under two sets of index：（1） water users＇ perception assessment of theirrigation works （14 indicators） and （2） assessment of the management efficiency in the irrigation works （six indicators）. Theresearch proposes the decentralization process from building, After determining the correlation coefficients, the multi-objective linearregression equation will be shown on six single objective functions. With the aim at achieving the highest efficiency in themanagement and exploitation of the irrigation works, there should be a shift in terms of the water users＇ perception of the irrigationworks. These study results also demonstrate that about 65%-68% of the change in the indicators of the exploitation efficiency in theirrigation works is explained by some water users＇ perception indexes of irrigation works, including the quality of irrigation service andthe output efficiency in agricultural production. By using the algorithm for multi-objective optimization problem, the optimal results inperception are determined. The input data is generated for the matrix supporting the decision making, and the decentralization ofmanagement and exploitation of irrigation works meets the three criteria, i.e., effectiveness, sustainability and flexibility.

关键词： Decentralization, irrigation management and exploitation, water user, irrigation services, Quan Lo-Phung Hiep, MekongRiver delta.

The Impact of China's WTO Entry on the Industrial Structure of the Yangtze River delta

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Journal of Donghua University(English Edition) 2002年第1期19卷 122-125页

作者：吴晓琼王维工李征邵世煌 College of Information Science and Technology Dong Hua University Shanghai 200051 Shanghai Municipal Committee Shanghai 200030

In the areas of China access into WTO Agreements,Chinese government has made lots of promises in reducing tariffs of some industrial products. While industrial products make up a very large share of import and export, so nearly all kinds of them will be influenced, especially those which are protected by means of national tariffs and taxes and non-tariffs barriers on import-sand, to a lesser extent, on *** we have noticed that most of these industries are the pillar ones of Yangtze delta. As it is well known that Yangtze delta.has become the most developed area in Yangtze valley or even in China and had an important effect on China economy. Thus entry to the WTO requires reform to be accelerated in this district so as to put the industry of this region in a position to be able to cope with the greater foreign competition that will follow accession to the trade body.

关键词： WTO, industry, Yangtze delta.