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AN APPROACH TO SEPARATING THE CURRENT VELOCITY IN ESTUARINE AND COASTAL WATERS

Journal of Hydrodynamics 2009年第4期21卷 512-519页

作者： NI Zhi-hui SONG Zhi-yao WU Li-chun State Key Laboratory of Hydrology-Water resources and Hydraulic Engineering Ocean College Hohai University Nanj ing 210098 China Key Laboratory of Virtual Geographic environment Ministry of Education Nanjing Normal University Nanjing 210097 China chongqing Education college Chongqing 400067 China

In the near-shore waters, the actual flow is mainly induced by tide, wind and salinity, and the river water runoff should also be included as a component in the estuary waters. The interactions among these major components are very complicated. Many approaches were proposed to study isolated tide and wind-driven currents or run-off based on the measured velocity, with all its components taken as a whole. In this article, firstly, based on the actual hydrodynamic characteristics of estuarine and coastal waters, an approach is proposed to separate the measured velocity by considering the theoretical current velocity profiles and using the least squares method. The vertical structures of tidal, wind-driven currents, density current and runoff can be obtained as well as their proportions in the measured velocity. Then, this approach is applied to the analysis of velocity data obtained in the North Branch of Yangtze River estuary and of laboratory test data. The results are found to be satisfactory. Finally, this approach is used to separate the measured velocity in the South Branch of Yangtze River estuary, to determine not only the bed friction velocity and roughness height, but also the surface wind stress, and to estimate the wind velocity data above the water surface. The results show that this method is simple in principle, practical in use, and reasonable in obtained results. So it can be used to effectively analyze the field data.

关键词： tide wind-driven current density current river water runoff friction velocity roughness height velocity separation

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Experiment study on water-rock interaction about gold activation and migration in different solutions

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Journal of Central South university of Technology 2001年第2期8卷 105-107页

作者： DAI Ta gen, GU Li, QIU Dong sheng, XIE Wen bing (college of resources, environment and Civil Engineering, Central South {3., Changsha 410083. china) 1. college of resources Environment and Civil Engineering Central South University 410083 Changsha China

The interactions on gold active and migratory quantities and rates between tuffaceous slate and solu tions with different compositions were experimentally studied at 200 ℃, 20 MPa, in a high pressure apparatus. After reaction, tuffaceous slate became light colored and soft, and its mass density reduced. The amount of gold extracted from tuffaceous slate ranges widely, from 0 027 to 0 23. μg/g. Chlorine solution may activate appreciable amount of gold, and the gold migratory rate is high enough, from 50 70% to 92 3.%, which reveals that sulphur and chlorine work together in solutions to accelerate gold activation and migration, and to realize gold mineralization in favorable places.

关键词： water rock interaction activation migration chlorine sulphur gold

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A NON-UNIFORM SEDIMENT TRANSPORT MODEL WITH THE BOUNDARY-FITTING ORTHOGONAL COORDINATE SYSTEM

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Journal of Hydrodynamics 2002年第1期14卷 64-68页

作者： Lu Yong-jun (River and Harbor Department, Nanjing Hydraulic Research Institute , Nanjing 210024, china) Chen Guo-xiang (college Water resources and {3., Hohai university, Nanjing 210024, china) River and Harbor Department Nanjing Hydraulic Research Institute Nanjing 210024 China college Water resources and environment Hohai University Nanjing 210024 china

A 2-D non-uniform sediment mat hmatical model in the boundary-fitting orthogonal coordinate system was develop ed in this paper. The governing equations, the numerical scheme, the boundary con ditions, the movable boundary technique and the numerical solutions were present ed. The model was verified by the data of the reach 25km upstream the Jialingjia ng estuary and the 44km long main stream of the chongqing reach of the Yangtze r iver. The calculated results show that, the water elevation, the velocity distri bution and the river bed deformation are in agreement with the measured data.

关键词： mathematical model non-uniform sus pended load non-uniform bedload boundary-fitting orthogonal coordinate system

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Econometric Study of Relationship between Change of Farmland Quantity and Policy of Farmland Protection in china

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Asian agricultural Research 2011年第3期3卷 75-78,82页

作者： PENG Ling,LIAO Tie-juncollege of resources and environment,{3. university,chongqing 400715,china college of resources and environment Southwest University

According to the data from Investigation Report of Land Use Change in china,The Land resources Communique of china and Chronicle of Statistical Data for Five Decades of New china issued from Ministry of Land resources,we select two indices:change of farmland quantity and policy of farmland *** to econometric theory,by using Eviewes 5.1 software,co-integration analysis,Granger causality test,impulse response and other analysis methods,we analyze the relationship between change of farmland quantity and policy of farmland protection in china since the reform and *** results show that there is long-term balanced relationship between change of farmland quantity and policy of farmland protection,and there is a certain mechanism restricting motion of variables between the two so as to make the two deviate from each other little and step towards balance in the long run;there is unilateral causality relationship between farmland change and policy of farmland protection,namely that the farmland change is the Granger cause of policy of farmland protection,while policy of farmland protection is not the Granger cause of farmland change;impulse response and variance decomposition indicate that farmland change plays the role of promoting policy of farmland protection continuously,and the role is strengthened along with prolonged lag period;the policy of farmland protection has strong inertia,because it is impacted by the former level of itself,and the policy of farmland protection plays insignificant role in promoting farmland ***,the important approach of solving problem of rapid decrease of farmland is to formulate long-term strategy,strengthen theoretical research of farmland protection and reinforce degree of formulation,implementation and surveillance of farmland protection policy.

关键词： Change of farmland quantity Policy of farmland pro

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THE GROUNDWATER resources AND ITSSUSTAINABLE DEVELOPMENTIN THE SOUTH EDGE OF TARIM BASIN

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Chinese Geographical Science 2001年第1期11卷 57-62页

作者： MA Jin-zhu, LI Ji-jun (college of resources & environment, Lanzhou {3., Lanzhou 73.000, P. R. china) college of resources & environment Lanzhou University Lanzhou P. R. China

There is a potential to certain extend for groundwater development in the piedmont plain in south edge of Tarim Basin. If the surface water use keeps the scale as present, the maximum safe yield of groundwater is about 2.05 × 109m3.a that is 55.8% of the recharge. Thus the evapotranspiration discharge will reduce 60.4%, while spring water reducing 3..6%. If the surface water use rate is up to 80% and coefficient of canal water use increase to 0.55 in the future, the maximum safe yield of groundwater will reduce to 1.85 × 109m3.a with the recharge reducing to 3.1 × 109m3. However, the sustainable groundwater development is depended on the protection of the quality aspect linked with the quantity aspect. In particular, protection of the glaoier and water conservation forestry in the Kunlun Mountains and coordinating development of surface water and groundwater should be taken seriously. Besides, the legislation, administrative management and the technology construction, and ability construction are also critical important and necessary.

关键词： groundwater resources sustainable development safe yield Tarim Basin

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Genotypic Differences in Grain Yield and Physiological Nitrogen Use Efficiency Among Rice Cultivars

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Pedosphere 2009年第6期19卷 681-691页

作者： ZHANG Ya-Li, FAN Jian-Bo, WANG Dong-Sheng and SHEN Qi-Rong2college of resources and environmental Sciences, Nanjing {3. university, Nanjing 210095 (china) [a]college of resources and environmental Sciences Nanjing Agricultural University Nanjing 210095 (China)

Efficient use of N in agricultural practice can increase yield, decrease production costs and reduce the risk of environmental pollution. Effects of N fertilizer application rates on grain yield and physiological N use efficiency (PE) in relation to the accumulation and redistribution of biomass and N in rice (Oryza sativa L.) cultivars were studied at two experimental farms of Nanjing agricultural {3., Nanjing, china in 2004. Three high N use efficiency (NUE) rice cultivars (Wuyunjing 7, Nanguang and 4007) and one low NUE rice cultivar (Elio) with similar growth patterns were studied under seven N rates (0, 60, 120, 180, 240, 3.0 and 3.0 kg ha -1 ). Grain yield increased with the N application rate and attained plateau at 180 kg N ha -1 for rice cultivars at each site. Increasing N rate decreased PE for biomass and grain yield. Grain yield and PE of Elio were about 20% and 18% lower than those of high NUE cultivars. Differences in biomass, N accumulation and N redistribution were observed at the post-heading stage among rice cultivars with differing NUEs. The less reproductive tillers of Elio resulted in less demand for C and N during grain filling, thus leading to lower PE of Elio compared with the high NUE rice cultivars.

关键词： accumulation biomass N application rate redistribution

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Effect of Lead-Zinc Interaction on Size of Microbial Biomass in Red Soil

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Pedosphere 1998年第2期8卷 143-148页

作者： K. S. KHAN and HUANG CHANGYONG college of Natural resources and environmental Sciences, Zhejiang {3. university, Hangzhou 3.0029 (china) Coll. National Research and environment Science Zhejiang Agricultural University Hangzhou 310029 China

A laboratory incubation experiment was conducted to evaluate the effects of lead and zinc applied alone or in various combinations on the size of microbial biomass in a red soil. Treatments included the application of lead at six different levels i.e., 0 (background), 100, 200, 3.0, 450 and 600 μg g -1 soil along with each of the four levels of zinc (0, 50, 150 or 250 μg g -1 soil). Application of lead or zinc alone to soil significantly ( P <0.001) affected the soil microbial biomass. The microbial biomass carbon (C mic ), biomass nitrogen (N mic ) and biomass phosphorus (P mic ) decreased sharply in soils contaminated with lead or zinc. Combined application of lead and zinc resulted in a greater biocidal effect on soil microbial biomass, which was significantly higher ( P <0.001) than that when either lead or zinc was applied alone. Consistent increase in the biomass C:N and decline in the biomass C:P ratios were also observed with the increased metal (Pb and Zn) toxicity in the soil.

关键词： interaction lead microbial biomass red soil zinc

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Spatial Variability of Micronutrients in Rice Grain and Paddy Soil

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Pedosphere 2009年第6期19卷 748-755页

作者： WANG Lin, WU Jia-Ping 2 , LIU Yan-Xuan, HUANG Hui-Qing and FANG Qian-Fang college of environment and Natural resources, Zhejiang {3., Hangzhou 3.0029 (china) [a]college of environment and Natural resources Zhejiang University Hangzhou 310029 (China)

Consumption of rice is the main source of micronutrients to human in Asia. A paddy field with unknown anthro- pogenic contamination in Deqing County, Zhejiang Province, china was selected to characterize the spatial variability and distribution of micronutrients in rice grain and soil. A total of 96 paired soil and rice grain samples were collected at harvest. The micronutrients in the soil samples were extracted by diethylenetriamine pentaacetic acid （DTPA）. The mean micronutrient concentrations in rice grain were 3.85 μg Cu g^-1, 11.6 μg Fe g^-1, 3..7 μg Mn g^-1 and 26.0 μg Zn g^-1 The mean concentrations were 2.54μg g^-1 for DTPA-Cu, 13..5μg g^-1 for DTPA-Fe, 3..6μg g^-1 for DTPA-Mn, and 0.84μg g^-1 for DTPA-Zn. Semivariograms showed that measured micronutrients in rice grain were moderately dependent, with a range distance of about 110 m. The concentrations of the DTPA-extractable micronutrients all displayed strong spatial dependency, with a range distance of about 60 m. There was some resemblance of spatial structure between soil pH and the grain Cu, Fe, Mn, and Zn. By analogy, similar spatial variation was observed between soil organic matter （SOM） and DTPA-extractable table micronutrients in the soil. Kriging estimated maps of the attributes showed the spatial distributions of the variables in the field, which is beneficial for better understanding the spatial variation of micronutrients and for potentially refining agricultural management practices at a field scale.

关键词： correlation dependency kriging soil properties

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Discovery of a pterodactylid pterosaur from the Yixian Formation of western Liaoning,china

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Chinese Science Bulletin 2001年第13期46卷 1112-1117页

作者： WANG Xiaolin & LU Junchang1. Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, china 2. college of Earth Sciences and resources, china university of Geo-sciences, Beijing 100083. china 3. Department of Geological Sciences, Southern Methodist university, Dallas, TX 75275, USA Institute of Vertebrate Paleontology Chinese Academy of Sciences Beijing 100044 China

A well-preserved pterosaur with nearly complete skull is described from the Lower Cretaceous Yixian Formation at Sihetun in western Liaoning. It is characterized by a low and long crestless skull, slender and pointed teeth, long metacarpal, nearly equal length of metatarsals I -III and short pedal digit V. It is referred to a new genus and species of the family Pterodactylidae: Haopterus gracilis gen. et sp. nov. This is the first pterosaur with a nearly complete skull from the Jehol Biota; it also represents the first non-controversial fossil record of Pterodactylidae in Asia. Haopterus is more derived than Pterodactylus from the Late Jurassic Solnhofen in Germany. This discovery extends the distribution of the family Pterodactylidae from Europe and Africa to Asia and its latest occurrence from the Late Jurassic to the Early Cretaceous. The discovery of Haopterus gracilis provides further evidence for the study of the originand radiation of the Jehol Biota; it also sheds new light on the evolution and

关键词： western Liaoning Early Cretaceous Yixian Formation Pterodactylidae.

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Comprehensive benefit of flood resources utilization through dynamic successive fuzzy evaluation model: A case study

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中国科学：技术科学英文版 2010年第2期53卷 529-538页

作者： FENG Feng1,2, XU ShiGuo1, LIU JianWei1, LIU Dan1,3.& WU Bo4 1 Institute of Water environment, School of Civil and Hydraulic Engineering, Dalian university of Technology, Dalian 116024, china 2 Yellow River Conservancy Technical Institute, Kaifeng 475003. china 3.college of Water resources, Shenyang agricultural university, Shenyang 110161, china 4 Office of Flood Control and Draught Relief in Jilin Province, Changchun 13.03., china 1. Institute of Water environment School of Civil and Hydraulic Engineering Dalian University of Technology Dalian 116024 China2. Yellow River Conservancy Technical Institute Kaifeng 475003 China3. College of Water Resources Shenyang Agricultural University Shenyang 110161 China4. Office of Flood Control and Draught Relief in Jilin Province Changchun 130033 China

Taking the flood resources utilization in Baicheng, Jilin during 2002–2007 as the research background, and based on the entropy weight and multi-level & multi-objective fuzzy optimization theory, this research established a multi-level & semi-constructive index system and dynamic successive evaluation model for comprehensive benefit evaluation of regional flood resources utilization. With the year 2002 as the base year, the analyzing results showed that there existed a close positive correlation between flood utilization volume and its benefits, comprehensive evaluation value and its comparison increment. Within the six successive evaluation years, the comprehensive benefit of 2003.was the best, in which the benefit evaluation increment reached 82.8% whereas the year of 2004 was the worst, in which the increment was only 18.2%. Thus the sustainability and correctness of the evaluation were verified by six years successive evaluation and increment comparison. The analyzing results showed that the economic benefits, ecological benefits and social benefits of flood utilization were remarkable, and that the comprehensive benefit could be improved by increasing flood utilization capacity, which would promote the regional sustainable development as well. The established dynamic successive evaluation provides a stable theoretical basis and technical support for further flood utilization.

关键词： flood resources utilization comprehensive benefit dynamic successive fuzzy evaluation Baicheng City

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