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Ecological rebuilding and land reclamation in surface mines in shanxi Province, China

Journal of Environmental sciences 2000年第4期12卷 486-497页

作者： MIAO Ze wei 1, BAI Zhong ke 2. GAO Lin 1 (1. Research Center for Eco Environmental sciences, Chinese Academy of sciences, Beijing 100085, China E\|mail: miaozewei@*** {2., shanxi agricultural university taigu, 03 中科院生态环境研究中心北京 1 0 0 0 85 山西师范大学山西临汾 0 3 0 80 1

It is well known that the mining industry produces a large amount of derelict land, and causes pollution of water loss and soil erosion as well as other environmental damage in China. As land is under pressure in China, it is now policy to restore or reclaim land despoiled by mining, the aim being to develop sustainable and healthy arable land ecosystems. This paper outlines the principles and approaches of ecological restoration, which have been adopted in shanxi Province with reference to three typical surface mines. In the research, the principles of ecological engineering and ecological succession are considered as the critical theories of ecological restoration in mine degraded land. Meanwhile, the paper made a comparative research on main links of ecological rebuilding in three surface mines in shanxi Province, which include new land construction, treatment of toxic substances, control of soil erosion, fertility management, irrigation, ecological planning and the establishment of legislation systems. As the research demonstrated, for successful restoration, new land construction is the fundamental framework, but it must be integrated with ecological engineering including ecological planning, the control of soil erosion and vegetation establishment and ecosystem creation in order to optimise land productivity and soil fertility. In addition, the establishment of the legislation systems and organization of administration are also indispensable aspects of ecological rebuilding in mined land.

关键词： ecological restoration land reclamation open-pit mine

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Critical Range of soil Boron for Prognosis of Boron Deficiency in Oilseed Rape

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Pedosphere 2001年第3期11卷 283-288页

作者： WEI YOUZHANG department of soil {2. and agricultural Chemistry, Zhejiang university, Hangzhou 31002. (China) 浙江大学浙江杭州 310029

Relationships between seed yields of oilseed rape (Brassica napus L.) and extractable boron concentrations in three soil layers (A, P and W) were investigated through ten experiments on three types of soils (Alluvic Entisols, Udic Ferrisols and Stagnic Anthrosols) in northern, western and middle Zhejiang Province. Among several mathematical models used to described the relationships, the polynomial equation, y = a + bx + cx2.+ dx3, where y is the yield of oilseed rape seed and x the extractable boron concentration in P layer of soil, was the best one. The critical range of the concentrations corresponding to 90% of the maximum oilseed rape yield was 0.40-0.52.mg kg-1. The extractable boron concentration of the P layers of the soils was the most stable. The critical range determined was verified through the production practices of oilseed rape in Zhejiang and Anhui provinces.

关键词： boron deficiency critical range oilseed rape soil layer

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Construction of a genetic map and localization of QTLs for yield traits in tomato by SSR markers

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Progress in Natural science:Materials International 2005年第9期15卷 793-797页

作者： LIU Yang 1,2., CHEN Huoying1**, WEI Yutang2.and ZHUANG Tianming1(1. department of Plant science, Shanghai Jiaotong {2., Shanghai 2.1101, China 2. department of Horticulture, Shenyang agricultural {2., Shenyang 110161, China) department of Plant science Shanghai Jiaotong University Shanghai 201101 China. department of Horticulture Shenyang Agricultural University Shenyang 110161 China

Using an F2.opulation derived from the hybrid of Lycopersicon esculentum Mill. ‘XF 98-7’× Lycopersicon pimpinellifolium LA2.84, a SSR genetic linkage map of tomato is constructed. The map contains 112.markers and spans 808.4 cM with an average distance of 7.2. cM between loci. Two quantitative trait loci （QTLs） for first flower node on chromosomes 5 and 11, two QTLs for number of flowers per truss on chromosomes 2.and 5, and five QTLs for fruit weight on chromosomes 1, 2. 3, 9 and 12.are identified.

关键词： tomato SSR markers genetic mapping first flower node number of flowers per truss fruit weight.

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The refined theory of deep rectangular beams based on general solutions of elasticity

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science China(Physics,Mechanics & Astronomy) 2006年第3期49卷 291-303页

作者： GAO Yang1 & WANG Minzhong2.1. College of science, China agricultural {2., Beijing 100083, China 2. State Key Laboratory for Turbulence and Complex Systems and department of Mechanics and Engi- neering science, Peking {2., Beijing 100871, China College of science China Agricultural University Beijing 100083 China State Key Laboratory for Turbulence Complex Systems department of Mechanics Engineering science Peking University Beijing 100871 China

The problem of deducing one-dimensional theory from two-dimensional the- ory for a homogeneous isotropic beam is investigated. Based on elasticity theory, the re- fined theory of rectangular beams is derived by using Papkovich-Neuber solution and Lur’e method without ad hoc assumptions. It is shown that the displacements and stresses of the beam can be represented by the angle of rotation and the deflection of the neutral surface. Based on the refined beam theory, the exact equations for the beam without transverse surface loadings are derived and consist of two governing differential equations: the fourth-order equation and the transcendental equation. The approximate equations for the beam under transverse loadings are derived directly from the refined beam theory and are almost the same as the governing equations of Timoshenko beam theory. In two ex- amples, it is shown that the new theory provides better results than Levinson’s beam the- ory when compared with those obtained from the linear theory of elasticity.

关键词： deep rectangular beams,the refined theory,Papkovich-Neuber solution,Lur'e method,governing equation

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The refined theory of transversely isotropic piezoelectric rectangular beams

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science China(Physics,Mechanics & Astronomy) 2006年第4期49卷 473-486页

作者： GAO Yang1 & WANG Minzhong2.1. College of science, China agricultural {2., Beijing 100083, China 2. State Key Laboratory for Turbulence and Complex Systems and department of Mechanics and Engi- neering science, Peking {2., Beijing 100871, China 1. College of science China Agricultural University Beijing 100083 China 2. State Key Laboratory for Turbulence and Complex Systems and department of Mechanics and Engineering science Peking University Beijing 100871 China

The problem of deducing one-dimensional theory from two-dimensional theory for a transversely isotropic piezoelectric rectangular beam is investigated. Based on the piezoelasticity theory, the refined theory of piezoelectric beams is derived by using the general solution of transversely isotropic piezoelasticity and Lur'e method without ad hoc assumptions. Based on the refined theory of piezoelectric beams, the exact equations for the beams without transverse surface loadings are derived, which consist of two governing differential equations: the fourth-order equation and the transcendental equation. The approximate equations for the beams under transverse loadings are derived directly from the refined beam theory. As a special case, the governing differential equations for transversely isotropic elastic beams are obtained from the corresponding equations of piezoelectric beams. To illustrate the application of the beam theory developed, a uniformly loaded and simply supported piezoelectric beam is examined.

关键词： rectangular beams, the refined theory, piezoelectric, transversely isotropic.

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Spectrofluorimetric determination of terbium with terephthalic acid

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Rare Metals 2002年第4期21卷 255-259页

作者： ZHAO Guohu and ZHAO JunBasic science department, Gansu {2. university, Lanzhou 730070, China Basic science department Gansu Agricultural University Lanzhou 730070

A Spectrofluorimetric method has been developed for the determination ofterbium(Ⅲ) based on the formation of a complex with terephthalic acid [benzene-1, 4-dicarboxylicacid (TPA)] in slightly acidic aqueous solution in the presence of gelatin. Terbium ion can form astable complex with TPA with the stoichiometry of 1:2. The best excitation and maximum emissionwavelengths are observed at 2.0 nm and 545 nm, respectively. The fluorescence intensity of terbiumcomplex gets the strongest within 2. min and remains stable up to 10 h, and it is proportional toterbium(Ⅲ) concentration in the range of 4.0x10^(-5)-1.6x10^(-7) mol·L^(-1) under the optimumconditions. The fluorescence system has good selectivity, sensitivity and stability. The relativestandard deviation is still within +-4% in the presence of 12.0-fold amounts of the other lanthanideions when the concentration of terbium(Ⅲ) is 1.0x10^(-6) mol·L^(-1) and common co-existing ionshardly interfere the determination. It has been applied to the direct fluorimetric determination oftrace terbium (Ⅲ) in rare earth ores and oxides.

关键词： terbium spectrofluorimetry terephthalic acid gelatin

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Diffusion of Chloride Ions in soils:*** of soil Moisture, Bulk Density and Temperature

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Pedosphere 1997年第1期7卷 65-72页

作者： XU MINGGANG, ZHANG YIPING and LIU WEINING (department of soil {2. and Agrochemistry, Northwestern agricultural university, Yangling, Shaanxi 712.00 China) department of soil {2. and Agrochemistry Northwestern Agricultural University Yangling Shaanxi 712100 China

Diffusion coefficients of chloride ions in four soils of different texture with varying effective moisture content and varying bulk density from 1.1 to 1.6 g cm3 under three different temperatures were determined by the diffusion-cell method using 36Cl-labelled CaCl2.solution. The results showed that activation energy decreased with water content, which indicated that the threshold for diffusion was lower at a higher soil moisture rate. Therefore, the diffusion coefficient (D) of chloride ions in soil increased consistently with soil moisture. Although a near linear increase in the diffusion coefficient with increasing soil moisture or bulk density in all the soils was observed, the increase rate in different soils was not the same. The D value increased with temperature, and with temperature increased by 10℃ in the range from 5 "C to 45℃ theD valve increased by 10%～30%, averaging about 2.%.

关键词： chloride ion diffusion coefficient soil bulk density soil moisture temperature

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Ability of Agrogyron elongatum to accumulate the single metal of cadmium, copper, nickel and lead and root exudation of organic acids

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Journal of Environmental sciences 2001年第3期13卷 368-375页

作者： YANG Hong 1, Jongathan W.C.Wong 2. YANG Zhi min\+1, ZHOU Li xiang 1(1. College of science, Nanjing agricultural {2., Nanjing\ 2.0095, China. 2. department of Biology, Hong Kong Baptist {2., China) College of science Nanjing Agricultural University Nanjing 210095 China.

Agrogyron elongatum were grown in nutrient solution containing moderate to high amounts of separate heavy metal of Cd, Cu, Ni and Ph in a greenhouse for a 9 - day. Cd, Cu, Ni and Ph generally led to decrease in the elongation of roots although the length of seedlings exposed to Cd and Ph at 0.05 and 0.5 mg/L showed to be slightly greater than that of controls. Of the four metals in the experiment, Ph was absorbed and accumulated to the highest level, with the concentrations of 92.54 mg/kg dry weight (DW) in roots and 11683 mg/kg DW in shoots. Cd was moderately accumulated in Agrogyron elongatum, but the maximum bioaccumulation coefficients (BCs) for roots and shoots were observed. The patterns for Cu and Ni uptake and distribution in plants differed from those of Ph and Cd, as it was showed that the shoot accumulation of Cu and Ni was significantly higher than in roots. A. elongation had the highest Ni concentration in shoots (302.1 mg/kg DW) at the external concentration of 2.0 mg/L. Cu ranked second, with a shoot concentration of 12.30 mg/kg DW when 50 mg/L Cu in solution was applied. For the four trace elements tested, the highest concentrations in shoots decreased by the order of Ni > Cu > Ph > Cd (mg/kg DW), and those in roots were Ph > Cd > Ni > Cu (mg/kg DW). Malic, oxalic and citric acids exuded by roots exposed to 1 and 50 mg/L of the metals were detected. Release of organic acids from plants significantly differed among the metal treatments. Cu was most effectively in inducing root exudation of the three types of organic acids. Cd, and Ni were also the inducers of secretion of malic and oxalic acids. With reference of Pb, a small amounts of malic and oxalic acids were detected in the root exudates, but few quantities, of citric acid were. found. However, no correlation between alternations in root exudation of organic acids and metal accumulation could be established.

关键词： heavy metal organic acid Agrogyron elongation hyperaccumulation

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Biomass of meiobenthic in the Bohai Sea, China

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Acta Oceanologica Sinica 2001年第3期20卷 435-442页

作者： Guo Yuqing, Zhang Zhinan, Mu Fanghong 1. department of Life science, Ocean {2. of Qingdao, Qingdao 2.6003, China 2. agricultural College, jimei {2., Xiamen 36102., China department of Life science Ocean University of Qingdao Qingdao 266003 China agricultural College Jimei University Xiamen 361021 China

A grid of 2. stations, giving a broad geographic coverage of the Bohai Sea and the Bohai Strait was selected. Undisturbed sediments were collected from sampling stations during cruises in June 1997, in September/October 1998 and again in April/May 1999. Based on the results of Juario (1975), the average biomass, 0.404 g/(m2.) of meiofauna (including nematode, harpacticoida, bivalve larvae, polycheata and kinorhyncha) in the Bohai Sea is given and accounts for 4.5 percent of the macrofauna in the Bohai Sea. The horizontal distribution of the biomass of meiofauna showed that it was higher at the stations of middle east part of the Bohai Sea and the strait in 1998 and 1999 cruises and it decreased at the stations near to the strait mouth and increased at Station B1 in 1999 cruise. The annual average production in the Bohai Sea is 3.636 g/m2.calculated in term of the formula P = 9B. Compared with the biomass of other sea areas in the world, the biomass of the Bohai Sea is similar but slightly lower. The individual average dry weight of nematodes given by different authors is analyzed.

关键词： Meiofauna free-living marine nematodes benthic copepods biomass the Bohai Sea

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Geostatistical Assessment of Pb,Zn and Cd Contamination in Near-Surface soils of the Urban-Mining Transitional Region of Isfahan,Iran

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Pedosphere 2010年第5期20卷 568-577页

作者： M.DAYANI J.MOHAMMADI department of soil {2. Agriculture FacultyRamin Agriculture and Natural Resources University department of soil {2. Agriculture FacultyShahrekord University

Due to the lack of regulation and environmental education and awareness, Sepahanshahr located in vicinity of Isfahan City, central Iran, is now a rapid growing residential area suffering from the considerable consequences of poorly regulated mining activities operating in its vicinity. A survey was carried out on soil Pb, Zn and Cd concentrations around Sepahanshahr Town to explore the spatial structure of Pb, Zn and Cd distribution and to map their concentrations using geostatistical techniques. 100 near-surface soil samples were collected and analyzed for Pb, Zn and Cd and some related soil physical and chemical variables such as pH, organic matter content, electrical conductivity, and clay, silt and sand contents. The variography results showed a strong spatial dependency in heavy metals concentration due to the dilution effects of natural factors including atmospheric dispersion and precipitation. The almost same range values calculated for both In-transformed Pb and sand data suggested presence of spatial co-regionalization. However, In-transformed Zn data showed a shorter spatial dependency among the three tested heavy metals. Kriged maps of all three heavy metals showed a strong gradient of contamination around the three mining sites activating in the area. The results of this study provide insight into identification of the extent and spatial variability of Pb, Zn and Cd pollution in the mining sites and surrounding urban areas.

关键词： heavy metals Kriging soil pollution spatial variability variogram

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