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Petrology, Age and Geodynamic Implication of the Panafrican Granitoids Associated with the Glito-Kpatala Shear Zone (South-East Togo)
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作者 Gnanwasou Alayi Sarakawa Abalo Malibida Kpanzou +3 位作者 Yao Agbossoumondé Essodina Padaro René-Pierre Menot Mahaman Sani Tairou 《International Journal of Geosciences》 2023年第12期1193-1225,共33页
The granitic plutons associated with the Glito-Kpatala shear zone are composed of biotite and amphibole granodiorites, biotite granites, two-mica granites and aplitic granites, which are very poorly represented. The c... The granitic plutons associated with the Glito-Kpatala shear zone are composed of biotite and amphibole granodiorites, biotite granites, two-mica granites and aplitic granites, which are very poorly represented. The chemical and mineralogical compositions of these facies indicate that they are I type and belong to high-K calc-alkaline series, with a chemical metaluminous character displayed by the granodiorites relative to the biotite and two-mica facies whose chemical compositions vary between metaluminous and peraluminous caracter. The Th/Ta (14.04 - 43.82 ppm, mean = 26.05), Th/U (2.58 to 15.05 ppm, mean = 5.85 ppm), Zr/Hf (25.27 to 37.21, mean = 30.67 ppm) and Rb/Sr (0.16 to 4.32;mean = 1.67 ppm) ratios of these granitoids reveal a strong crustal involvement in their magmatogenesis. Variations in CaO/Na<sub>2</sub>O (0.47 - 1.44 ppm), Rb/Sr (0.14 - 0.27 ppm), Rb/Ba (0.07 - 0.14 ppm) and Sr/Y (38.21 - 174.42 ppm) ratios indicate that biotite and amphibole granodiorites with their excessive Ni (135.37 - 139.51 ppm) and Cr (395.73 - 447.74 ppm) were derived from a mafic to intermediate lower continental crust where garnet and/or amphibole were stable residual assemblage minerals. The moderate Sr/Y ratios (1.81 - 9.47 ppm) and low transition elements Ni (1 - 6.44 ppm) and Cr (7.89 - 13.47 ppm) contents in both the two-mica and biotite granites are consistent with their emplacement at relatively shallow depths in the upper to mean continental crust, at pressures below 10 Kbar. In the two-mica granites, moderate CaO/Na<sub>2</sub>O (0.20 - 0.57 ppm, mean = 0.38 ppm) and Rb/Ba (0.39 - 1.37, mean = 0.84 ppm) ratios and quite varied Rb/Sr (1.53 - 4.23 ppm, mean = 2.85 ppm) ratios indicate a predominant derivation from psammitic and pelitic metasediments rather than metagreywackes. These low ratios (0.25 ≤ CaO/Na<sub>2</sub>O ≤ 0.32, mean = 0.28 ppm;0.31 ≤ Rb/Ba ≤ 0.44, mean = 0.39 ppm;1.11 ≤ Rb/Sr ≤ 1.78, mean = 0.39 ppm) in biotite granites are more consistent with melting from a metagreywacke-derived source. Evidence for the contribution of mantle-derived mafic magma with granitic magma in the plutons studied is materialized by the presence of magmatic enclaves in both granodiorites and two-mica granites, the volcanic arc geochemical signatures displayed by the plutons in geotectonic diagrams and Nb/Ta ratios (14.14 - 34.61 ppm) closer to mantle estimates. Geochemical data and radiometric dating elements suggest that the granitoids studied can be integrated into the pan-African late magmatic episode, which corresponds between 606 and 583 Ma, to the activity of transcurrent ductile strike-slips and to the synchronous emplacement of high K calc-alkaline plutons in a post-collisional context. 展开更多
关键词 Pan-African Granitoids Post-Collisional Shear Zone south-East Togo
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Eco-environmental benefit assessment of China's South-North Water Transfer Scheme——the middle route project
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作者 DUANGuang-ming ZHAOJing-zhu LIUGuo-hua KEBing XIAOHan WUGang DENGHong-bing 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第2期308-315,共8页
This paper assess the eco-environmental benefits that may come from the middle route project of China's South-North Water Transfer Scheme(SNWT) with principles and methods of eco-economics and planning reports of ... This paper assess the eco-environmental benefits that may come from the middle route project of China's South-North Water Transfer Scheme(SNWT) with principles and methods of eco-economics and planning reports of SNWT's middle route project. Some benefits were calculated in monetary units. To make sure that the results can be comparable with normal monetary indices, concrete assessment objects and the parameters are prudently selected according to the major characteristics of the project and its water import region. Primary assessment revealed that in different project construction stages, the benefit could be more than 13 07 billion RMB Yuan in 2010 and 19 79 billion RMB Yuan in 2030, respectively. The monetary value tends to increase with social-economic development. To realize these potential benefits, however, calls for more endeavors. 展开更多
关键词 China's south-North Water Transfer Scheme(SNWT) the middle route project of south-North Water Transfer(MRPSNWT) assessment ecosystem services monetary indices
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Optimal Operation for Baoying Pumping Station in East Route Project of South-to-North Water Transfer 被引量:7
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作者 FENG Xiaoli QIU Baoyun +2 位作者 CAO Haihong WEI Qianglin TENG Haibo 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2009年第1期78-83,共6页
Baoying pumping station is a part of source pumping stations in East Route Project of South-to-North Water Transfer in China. Aiming at the characteristics of head varying, and making use of the function of pump adjus... Baoying pumping station is a part of source pumping stations in East Route Project of South-to-North Water Transfer in China. Aiming at the characteristics of head varying, and making use of the function of pump adjustable blade, mathematical models of pumping station optimal operation are established and solved with genetic algorithm. For different total pumping discharge and total pumping volume of water per day, in order to minimize pumping station operation cost, the number and operation duties of running pump units are respectively determined at different periods of time in a day. The results indicate that the saving of electrical cost is significantly effected by the schemes of adjusting blade angles and time-varying electrical price when pumping certain water volume of water per day, and compared with conventional operation schemes (namely, the schemes of pumping station operation at design blade angles based on certain pumping discharge), the electrical cost is saved by 4.73%-31.27%. Also, compared with the electrical cost of conventional operation schemes, the electrical cost is saved by 2.03%-5.79% by the schemes of adjusting blade angles when pumping certain discharge. 展开更多
关键词 south-to-North Water Transfer Baoying pumping station optimal operation adjusting blade angle time-varying electrical price
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Optimization and coordination of South-to-North Water Diversion supply chain with strategic customer behavior 被引量:4
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作者 Zhi-song CHEN Hui-min WANG 《Water Science and Engineering》 EI CAS 2012年第4期464-477,共14页
The South-to-North Water Diversion (SNWD) Project is a significant engineering project meant to solve water shortage problems in North China. Faced with market operations management of the water diversion system, th... The South-to-North Water Diversion (SNWD) Project is a significant engineering project meant to solve water shortage problems in North China. Faced with market operations management of the water diversion system, this study defined the supply chain system for the SNWD Project, considering the actual project conditions, built a decentralized decision model and a centralized decision model with strategic customer behavior (SCB) using a floating pricing mechanism (FPM), and constructed a coordination mechanism via a revenue-sharing contract. The results suggest the following: (1) owing to water shortage supplements and the excess water sale policy provided by the FPM, the optimal ordering quantity of water resources is less than that without the FPM, and the optimal profits of the whole supply chain, supplier, and external distributor are higher than they would be without the FPM; (2) wholesale pricing and supplementary wholesale pricing with SCB are higher than those without SCB, and the optimal profits of the whole supply chain, supplier, and external distributor are higher than they would be without SCB; and (3) considering SCB and introducing the FPM help increase the optimal profits of the whole supply chain, supplier, and external distributor, and improve the efficiency of water resources usage. 展开更多
关键词 south-to-North Water Diversion supply chain strategic customer behavior floatingpricing mechanism
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Fluid Inclusion Geochemistry of Metallic Ore Deposits in the South- Central Sector of theDa Hinggan Mountains in China 被引量:3
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作者 Sheng Jifu, Zhang Dequan and Li YanInstitute of Mineral Deposits, Chinese Academy of Geological Sciences, Beijing Jiang M inxi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1995年第3期289-302,共14页
Physicochemical parameters of mineralization such as temperature, pressure, salinity, density, composition and boiling of ore fluids as well as pH, Eh, fo2 and reducing parameter in theprocess of mineralization of maj... Physicochemical parameters of mineralization such as temperature, pressure, salinity, density, composition and boiling of ore fluids as well as pH, Eh, fo2 and reducing parameter in theprocess of mineralization of major ore deposits in the study district have been obtained by the authors through systematic observation and determination of characteristics and phase changes of fluid inclusions at different temperatures and analysis of gaseous and liquid phase compositions of the inclusions, thus providing a scientific basis for the division of mineralization-alteration stages, types of mineral deposits and minerogenetic series and the deepening of the knowledge about the ore-forming processes and mechanisms of mineral deposits. It is indicated that the deposits of the same type have similar fluid inclusion geochemical features and physicochemical parameters though they belong to different minerogenetic series, while the compositions of inclusions are not conditioned by deposit types but closely related to the minerogenetic series of deposits. 展开更多
关键词 south-central sector of the Da Hinggan Mountains metallic ore deposit fluid inclusion geochemistry
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Epidemiology of hepatitis E in South-East Europe in the "One Health" concept 被引量:2
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作者 Anna Mrzljak Petra Dinjar-Kujundzic +5 位作者 Lorena Jemersic Jelena Prpic Ljubo Barbic Vladimir Savic Vladimir Stevanovic Tatjana Vilibic-Cavlek 《World Journal of Gastroenterology》 SCIE CAS 2019年第25期3168-3182,共15页
The significance of hepatitis E virus(HEV)as an important public health problem is rising.Until a decade ago,cases of HEV infection in Eur-ope were mainly confined to returning travelers,but nowadays,hepatitis E repre... The significance of hepatitis E virus(HEV)as an important public health problem is rising.Until a decade ago,cases of HEV infection in Eur-ope were mainly confined to returning travelers,but nowadays,hepatitis E represents an emerging zoonotic infection in many European countries.The aim of this manuscript is to perform a systematic review of the published literature on hepatitis E distribution in humans,animals and environmental samples("One Health"concept)in the South-Eastern European countries.Comparison of the available data showed that the anti-HEV seroprevalence in the South-Eastern Europe varies greatly,depending on the population studied,geographical area and methods used.The IgG seroprevalence rates in different population groups were found to be 1.1%-24.5%in Croatia,up to 20.9%in Bulgaria,5.9-%17.1%in Romania,15%in Serbia,up to 9.7%in Greece and 2%-9.7%in Albania.Among possible risk factors,older age was the most significant predictor for HEV seropositivity in most studies.Higher seroprevalence rates were found in animals.HEV IgG antibodies in domestic pigs were detected in 20%-54.5%,29.2%-50%,38.94%-50%and 31.1%-91.7%in Serbia,Bulgaria,Romania and Croatia,respectively.In wild boars seroprevalence rates were up to 10.3%,30.3%and 31.1%in Romania,Slovenia and Croatia,respectively.A high HEV RNA prevalence in wild boars in some countries(Croatia and Romania)indicated that wild boars may have a key role in the HEV epidemiology.There are very few data on HEV prevalence in environmental samples.HEV RNA was detected in 3.3%and 16.7%surface waters in Slovenia and Serbia,respectively.There is no evidence of HEV RNA in sewage systems in this region.The available data on genetic characterization show that human,animal and environmental HEV strains mainly belong to the genotype 3. 展开更多
关键词 Hepatitis E virus "One-Health" Humans Animals Environment south-East EUROPE
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Critical discharge at Datong for controlling operation of South-to-North Water Transfer Project in dry seasons 被引量:3
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作者 Wang Yigang Huang Huiming Li Xi 《Water Science and Engineering》 EI CAS 2008年第2期47-58,共12页
关键词 saltwater intrusion critical discharge at Datong water diversion the south-to-North Water Transfer Project
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Reliability model of organization management chain of South-to-North Water Diversion Project during construction period 被引量:3
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作者 Feng Jingchun Zhou Yang +2 位作者 Hong Yuzhen Zhao Shixin Ren Xiaoqiang 《Water Science and Engineering》 EI CAS 2008年第4期107-113,共7页
In order to analyze the indispensability of the organization management chain of the South-to-North Water Diversion Project (SNWDP), two basic forms (series connection state and mixed state of both series connectio... In order to analyze the indispensability of the organization management chain of the South-to-North Water Diversion Project (SNWDP), two basic forms (series connection state and mixed state of both series connection and parallel connection) of the organization management chain can be abstracted. The indispensability of each form has been studied and is described in this paper. Through analysis of the reliability of the two basic forms, reliability models of the organization management chain in the series connection state and the mixed state of both series connection and parallel connection have been set up. 展开更多
关键词 south-to-North Water Diversion Project reliability model management chain parallel connection series connection
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Critical chain construction with multi-resource constraints based on portfolio technology in South-to-North Water Diversion Project 被引量:3
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作者 Jing-chun FENG Lei LI +4 位作者 Nan YANG Yu-zhen HONG Min PANG Xiong YAO Li-cheng WANG 《Water Science and Engineering》 EI CAS 2011年第2期225-236,共12页
Recently, the critical chain study has become a hot issue in the project management research field. The construction of the critical chain with multi-resource constraints is a new research subject. According to the sy... Recently, the critical chain study has become a hot issue in the project management research field. The construction of the critical chain with multi-resource constraints is a new research subject. According to the system analysis theory and project portfolio theory, this paper discusses the creation of project portfolios based on the similarity principle and gives the definition of priority in multi-resource allocation based on quantitative analysis. A model with multi-resource constraints, which can be applied to the critical chain construction of the A-bid section in the South-to-North Water Diversion Project, was proposed. Contrast analysis with the comprehensive treatment construction method and aggressive treatment construction method was carried out. This paper also makes suggestions for further research directions and subjects, which will be useful in improving the theories in relevant research fields. 展开更多
关键词 multi-resource constraints south-to-North Water Diversion Project project portfolio critical chain
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Historical Change on Distribution and Quantity of the South-China Tiger (Panthera tigris amoyensis) 被引量:2
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作者 金昆 郑冬 +1 位作者 洪美玲 王力军 《Journal of Forestry Research》 SCIE CAS CSCD 1998年第2期136-138,共3页
As one of five survived tiger subspecies, the South-China tiger (Panthera tigris amoyensis) specially disperses in China. This paper dedicated distribution and quantity of wild South-China tiger, and also introduced d... As one of five survived tiger subspecies, the South-China tiger (Panthera tigris amoyensis) specially disperses in China. This paper dedicated distribution and quantity of wild South-China tiger, and also introduced distribution, quantity and pedigree of captive South-China tiger. In the middle of this century, about several thousands South-China tiger distributed in following provinces, such as Hunan, Jiangxi, Guizhou, Fujian, Guangdong, Guangxi, Zhejiang, Hubei, Sichuan, Henan, Shanxi, Shanxi, Gansu. etc. Until now, there are only about 20–30 wild South-China tigers distributing in the provinces of Guangdong, Fujian, Jiangxi, and Hunan, Sichuan, and 50 captive South-China tiger are raised in zoos of China. 展开更多
关键词 south-China tiger (Panthera tigris amoyensis) DISTRIBUTION Quantity
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Research on Expansive Soils Encountered in Middle Route Project of South-to-north Water Transfer Canal 被引量:2
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作者 GONG Bi-weiSenior Engineer, Yangtze River Scientific Research Institute, Changjiang Water Resources Commission, Wuhan, 430010, China ZHOU Xiao-wenSenior Engineer, Yangtze River Scientific Research Institute, Changjiang Water Resources Commission, Wuhan, 430010, China BAO Chen-gangProfessor-Senior Engineer, Yangtze River Scientific Research Institute, Changjiang Water Resources Commission, Wuhan, 430010, China 《人民长江》 北大核心 2002年第S1期36-39,共4页
The main canal of the Middle Route Project of South-to-North Water Transfer totals more than 1 240 km in length. In Henan Province and Hebei Province, there will be a section of more than 120 km passing through an exp... The main canal of the Middle Route Project of South-to-North Water Transfer totals more than 1 240 km in length. In Henan Province and Hebei Province, there will be a section of more than 120 km passing through an expansive soils area. Expansive soils is a special kind of tenacious clay, which swells when meeting with water and shrinks when losing water. With complicated mechanical properties, it changes with the variation of water content. As a result, expansive soils become the key object of study on unsaturated soils mechanics for the project. From the status of study on unsaturated soils at home and abroad, this paper covers an analysis on stability analysis method of expansive soils slope, determination of expansive soils strength, rational design of canal slope ratio and support, and forecast of landslide for the Middle Route Project of South-to-North Water Transfer. 展开更多
关键词 Unsaturated SOILS Expansive SOILS Suction the south-to-North Water Transfer CANAL
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Resolution pattern of jaundice among children presenting with severe malaria in rural South-West Nigeria 被引量:1
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作者 Osonuga OA Osonuga A +1 位作者 Osonuga AA Osonuga IO 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2012年第7期551-553,共3页
Objective:To compare the pattern of jaundice resolution among children with severe malaria treated with quinine and artemether.Methods:Thirty two children who fulfilled the inclusion criteria were recruited for the st... Objective:To compare the pattern of jaundice resolution among children with severe malaria treated with quinine and artemether.Methods:Thirty two children who fulfilled the inclusion criteria were recruited for the study from two hospitals with intensive care facilities.They were divided into two groups:'Q' and 'A',receiving quinine and artemether.respectively.Jaundice was assessed by clinical examination.Results:Sixteen out of 32 children recruited(representing50%) presented with jaundice on the dav of recruitment.The mean age was(7.00±2.56) years.On day 3,tour patients in 'A' and six patients in 'O' had jaundice.By day 7.no child had jaundice.Conclusion:The study has shown that hoth drugs resolve jaundice although artemether relatively resolves it faster by the third day. 展开更多
关键词 JAUNDICE Quinine Artemether Severe malaria south-west NIGERIA
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THE TIMING OF SOUTH-ASIAN HIGH ESTABLISHMENT AND ITS RELATION TO TROPICAL ASIAN SUMMER MONSOON AND PRECIPITATION OVER EAST-CENTRAL CHINA IN SUMMER 被引量:3
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作者 王黎娟 郭帅宏 葛静 《Journal of Tropical Meteorology》 SCIE 2016年第2期136-144,共9页
The timing of the South Asian High(SAH) establishment over the Indochina Peninsula(IP) from April to May and its relations to the setup of the subsequent tropical Asian summer monsoon and precipitation over eastern-ce... The timing of the South Asian High(SAH) establishment over the Indochina Peninsula(IP) from April to May and its relations to the setup of the subsequent tropical Asian summer monsoon and precipitation over eastern-central China in summer are investigated by using NCEP/NCAR daily reanalysis data,outgoing longwave radiation(OLR)data and the daily precipitation data from 753 weather stations in China.It is found that the transitions of the zonal wind vertical shear and convection establishment over tropical Asia are earlier(later) in the years of early(late) establishment of SAH.In the lower troposphere,anti-cyclonic(cyclonic) anomaly circulation dominates the equatorial Indian Ocean.Correspondingly,the tropical Asian summer monsoon establishes earlier(later).Furthermore,the atmospheric circulation and the water vapor transport in the years of advanced SAH establishment are significantly different from the delayed years in Asia in summer.Out-of-phase distribution of precipitation in eastern-central China will appear with a weak(strong) SAH and western Pacific subtropical high,strong(weak) ascending motion in the area south of Yangtze River but weak(strong) ascending motion in the area north of it,and cyclonic(anti-cyclonic) water vapor flux anomaly circulation from the eastern-central China to western Pacific.Accordingly,the timing of the SAH establishment at the upper levels of IP is indicative of the subsequent onset of the tropical Asian summer monsoon and the flood-drought pattern over eastern-central China in summer. 展开更多
关键词 south-Asian High Indochina Peninsula tropical Asian summer monsoon precipitation over eastern-central China in summer
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Evolution trend of the water quality in Dongping Lake after South-North Water Transfer Project in China 被引量:2
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作者 HU Zun-fang KANG Feng-xin +4 位作者 ZOU An-de YU Lin-song LI Yang TIAN Tong-liang KANG Gui-ling 《Journal of Groundwater Science and Engineering》 2019年第4期333-339,共7页
To investigate the evolution trend of water quality in Dongping Lake after South-North Water Transfer Project operation as well as to ensure the safe usage of the water receiving areas, water samples were collected an... To investigate the evolution trend of water quality in Dongping Lake after South-North Water Transfer Project operation as well as to ensure the safe usage of the water receiving areas, water samples were collected and determined before and after water delivery in different hydrological seasons. Then, comprehensive pollution index method, comprehensive nutrition state index method and health risk assessment model were utilized to evaluate the quality, nutrition, and health risk of Dongping Lake water. Results showed that the quality of Dongping Lake water still met level Ⅲ (light pollution) no matter before or after water delivery. The nutrition state was improved from light eutropher before water delivery to mesotropher after water delivery. The health risk level was reduced from high-medium before water delivery to medium level after water delivery. In summary, the operation of the eastern route of South-North Water Transfer Project is beneficial for water environment improvement of Dongping Lake. 展开更多
关键词 south-North WATER Transfer Project Dongping LAKE WATER quality NUTRITION Health risk
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Land Cover Changes and Drivers in the Water Source Area of the Middle Route of the South-to-North Water Diversion Project in China from 2000 to 2015 被引量:2
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作者 GAO Wenwen ZENG Yuan +2 位作者 ZHAO Dan WU Bingfang REN Zhiyuan 《Chinese Geographical Science》 SCIE CSCD 2020年第1期115-126,共12页
The Middle Route of the South-to-North Water Diversion Project(MR-SNWDP)in China,with construction beginning in 2003,diverts water from Danjiangkou Reservoir to North China for residential,agriculture and industrial u... The Middle Route of the South-to-North Water Diversion Project(MR-SNWDP)in China,with construction beginning in 2003,diverts water from Danjiangkou Reservoir to North China for residential,agriculture and industrial use.The water source area of the MR-SNWDP is the region that is most sensitive to and most affected by the construction of this water diversion project.In this study,we used Landsat Thematic Mapper(TM)and HJ-1 A/B images from 2000 to 2015 by an object-based approach with a hierarchical classification method for mapping land cover in the water source area.The changes in land cover were illuminated by transfer matrixes,single dynamic degree,slope zones and fractional vegetation cover(FVC).The results indicated that the area of cropland decreased by 31%and was replaced mainly by shrub over the past 15 years,whereas forest and settlements showed continuous increases of 29.2% and 77.7%,respectively.The changes in cropland were obvious in all slope zones and decreased most remarkably(–43.8%)in the slope zone above 25°.Compared to the FVC of forest and shrub,significant improvement was exhibited in the FVC of grassland,with a growth rate of 16.6%.We concluded that local policies,including economic development,water conservation and immigration resulting from the construction of the MR-SNWDP,were the main drivers of land cover changes;notably,they stimulated the substantial and rapid expansion of settlements,doubled the wetlands and drove the transformation from cropland to settlements in immigration areas. 展开更多
关键词 remote sensing land cover change object-based classification Middle Route of the south-to-North Water Diversion Project(MR-SNWDP) China
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Forecasting Loss of Ecosystem Service Value Using a BP Network: A Case Study of the Impact of the South-to-north Water Transfer Project on the Ecological Environmental in Xiangfan, Hubei Province, China 被引量:1
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作者 YUN-FENG CHEN, JING-XUAN ZHOU, JIE XIAO, AND YAN-PING LIEnvironmental Science and Engineering College, Huazhong University of Science and Technology, Wuhan 430074, Hubei, China 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2003年第4期379-391,共13页
Objective To recognize and assess the impact of the South-to-north Water Transfer Project (SNWTP) on the ecological environment of Xiangfan, Hubei Province, situated in the water-out area, and develop sound scientific... Objective To recognize and assess the impact of the South-to-north Water Transfer Project (SNWTP) on the ecological environment of Xiangfan, Hubei Province, situated in the water-out area, and develop sound scientific countermeasures. Methods A three-layer BP network was built to simulate topology and process of the eco-economy system of Xiangfan. Historical data of ecological environmental factors and socio-economic factors as inputs, and corresponding historical data of ecosystem service value (ESV) and GDP as target outputs, were presented to train and test the network. When predicted input data after 2001 were presented to trained network as generalization sets, ESVs and GDPs of 2002, 2003, 2004... till 2050 were simulated as output in succession. Results Up to 2050, the area would have suffered an accumulative total ESV loss of RMB 104.9 billion, which accounted for 37.36% of the present ESV. The coinstantaneous GDP would change asynchronously with ESV, it would go through an up-to-down process and finally lose RMB89.3 billion, which accounted for 18.71% of 2001. Conclusions The simulation indicates that ESV loss means damage to the capability of socio-economic sustainable development, and suggests that artificial neural networks (ANNs) provide a feasible and effective method and have an important potential in ESV modeling. 展开更多
关键词 Artificial neural network BP Ecosystem service value south-to-north Water Transfer Project
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Research of the Conductive Structure of Crust and the Upper Mantle beneath the South-Central Tibetan Plateau 被引量:1
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作者 叶高峰 金胜 +1 位作者 魏文博 Martyn Unsworth 《Journal of China University of Geosciences》 SCIE CSCD 2007年第4期334-343,共10页
With the super-wide band magnetoteiluric sounding data of the JUong (吉隆)-Cuoqin (措勤) profile (named line 800) which was completed in 2001 and the Dingri (定日)-Cuomai (措迈) profile (named line 900) wh... With the super-wide band magnetoteiluric sounding data of the JUong (吉隆)-Cuoqin (措勤) profile (named line 800) which was completed in 2001 and the Dingri (定日)-Cuomai (措迈) profile (named line 900) which was completed in 2004, we obtained the strike direction of each MT station by strike analysis, then traced profiles that were perpendicular to the main strike direction, and finally obtained the resistivity model of each profile by nonlinear conjugate gradients (NLCG) inversion. With these two models, we described the resistivity structure features of the crust and the upper mantle of the center-southern Tibetan plateau and its relationship with Yalung Tsangpo suture: the upper crust of the research area is a resistive layer with resistivity value range of 200-3 000 Ω.m. The depth of its bottom surface is about 15-20 km generally, but the bottom surface of resistive layer is deeper in the middle of these two profiles. At llne 900, it is about 30 km deep, and even at line 800, it is about 38 km deep. There is a gradient belt of resistivity at the depth of 15-45 km, and a conductive layer is beneath it with resistivity even less than 5 Ω.m. This conductive layer is composed of individual conductive bodies, and at the south of the Yalung Tsangpo suture, the conductive bodies are smaller with thickness about 10 km and lean to the north slightly. However, at the north of the Yalung Tsangpo suture, the conductive bodies are larger with thickness about 30 km and also lean to the north slightly. Relatively, the conductive bodies of line 900 are thinner than those of line 800, and the depth of the bottom surface of line 900 is also shallower. At last, after analyzing the effect factors to the resistivity of rocks, it was concluded that the very conductive layer was caused by partial melt or connective water in rocks. It suggests that the middle and lower crust of the center-southern Tibetan plateau is very thick, hot, flabby, and waxy. 展开更多
关键词 south-central Tibet magnetotelluric sounding nonlinear conjugate gradients inversion conductive structure partial melt.
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Geological conditions and key rock mechanics issues in the Western Route of South-to-North Water Transfer Project 被引量:2
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作者 XuechaoWang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE 2011年第3期234-243,共10页
In terms of special geological conditions of the Western Route of South-to-North Water Transfer Project, the classification method for surrounding rocks is discussed by combining with the construction method of tunnel... In terms of special geological conditions of the Western Route of South-to-North Water Transfer Project, the classification method for surrounding rocks is discussed by combining with the construction method of tunnel boring machine (TBM). The classification standard of surrounding rocks is put forward on the basis of physical simulations and engineering practices. Damage, deformation and evolution of surrounding rocks induced by TBM excavation are discussed. Meanwhile, the long-term deformation mechanisms and stability of surrounding rocks are also studied. On this basis, a three-dimensional constitutive model for interbedded sandstone slate and a fiat shell-joint element-foundation system for calculating internal forces of segment lining are established. The deformation features of surrounding rocks of deep and steep interbedded sandstone slate and their influences on internal forces of segment lining are presented. Finally, the design methods of segment lining constructed in deep and steep flysch are proposed. 展开更多
关键词 the Western Route of south-to-North Water Transfer Project rock mechanics issues classification of surrounding rocks stability of surrounding rocks excavation-induced damage lining design
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SEM Morphological Study of the Paratype of the Spinicaudatan <i>Feiyunella zhedongensis</i>(Chen and Shen, 1977) from Cretaceous of Linhai, Zhejiang, South-East China 被引量:1
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作者 Xiao Teng Gang Li 《Open Journal of Geology》 2019年第10期613-615,共3页
Spinicaudatans, a suborder of the abandoned taxonomic group “Conchostraca”, are very useful for biostratigraphic subdivision and correlation of the non-marine successions, remarkably in otherwise fossil-scarce red b... Spinicaudatans, a suborder of the abandoned taxonomic group “Conchostraca”, are very useful for biostratigraphic subdivision and correlation of the non-marine successions, remarkably in otherwise fossil-scarce red beds. Feiyunella, a monospecies spinicaudatan genus, was established based on specimens from sediments of Upper Cretaceous red beds in different localities of Zhejiang Province. The morphological examination under a scanning electron microscope of the type specimens of Feiyunella zhedongensis (Chen and Shen, 1977) has found that the paratype from the Fangyan Formation at Xiaoling of Linhai City, Zhejiang Province, is not Feiyunella, but a younger individual of Linhaiella. 展开更多
关键词 Spinicaudatan Feiyunella Linhaiella Taxonomy CRETACEOUS south-East China
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Penalty model for delay of bidding section construction period in South-to-North Water Diversion Eastern Route Project from perspective of programs 被引量:2
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作者 Jing-chun FENG Ya-fang REN +2 位作者 Zhong-nan DUAN Zhan-jun LIU Hai-yang LI 《Water Science and Engineering》 EI CAS 2012年第3期350-360,共11页
According to the multi-project and program management theory, this paper analyzes the program generation principle and establishes a program based on progress goals. On the basis of the present situation of calculatio... According to the multi-project and program management theory, this paper analyzes the program generation principle and establishes a program based on progress goals. On the basis of the present situation of calculation of penalty for delay of the bidding section construction period with the critical path method, we studied the effects of contractor-induced delay of the bidding section construction period in detail, including the effects on the construction period of the bidding section itself, the earliest start times of the next bidding section and other subsequent bidding sections, and the construction period of the program, and then constructed a penalty model for delay of the bidding section construction period from the perspective of programs. Using the penalty model, we conducted a practical analysis of penalty for delay of the construction period of the Baoying station program in the South-to-North Water Diversion Project. The model can help determine the amount of penalty for delay of the construction period in bidding sections scientifically and reasonably, 展开更多
关键词 program establishment program management bidding section construction period critical path method (CPM) penaly model south-to-North Water Diversion Project
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