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Saline-alkali soil reclamation and utilization in china:progress and prospects

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Frontiers of Agricultural Science and Engineering 2024年第2期11卷 216-228页

作者： guangzhou WANG Gang NI Gu feng Haley MBURRILL Jianfang LI Junling ZHANG Fusuo ZHANG State Key Laboratory of Nutrient Use and Management(SKLNUM) College of Resources and Environmental SciencesNational Academy of Agriculture Green DevelopmentChina Agricultural UniversityBeijing 100193China The institute of Ecology and Evolution University of OregonEugeneOR97403USA

Soil salinity is a global threat to the productivity of arable land. With the impact of population growth and development of social economy in china, the area of arable land has been shrinking in recent decades and is approaching a critical threshold of 12. Mha, the minimum area for maintaining the national food security. Saline-alkaline land, as important backup reserve, has been receiving increased attention as an opportunity to expand land resources. This review first summarizes the general principles and technologies of saline soil reclamation to support plant growth, including leaching salts or blocking the rise of salts, and soil fertility enhancement to improve the buffering *** the progress in this area in china is described including the customization of technologies and practices used in different saline-alkali regions. Following the soil management strategies, the concept of selecting crops for saline soil is proposed. This encompasses halophyte planting, salt-tolerant crop breeding and the application of saline-adapted functional microorganisms to improve the adaptation of crops. Finally, the current problems and challenges are evaluate, and future research directions and prospects proposed for managing this major soil constraint.

关键词： Food security land reserve reclamation saline-alkali soil utilization

Magmatic-hydrothermal Evolution and Mineralization Mechanisms of the Wangjiazhuang Cu(-Mo)Deposit in the Zouping Volcanic Basin,Shandong Province,china:Constraints from Fluid Inclusions

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 679-700页

作者： SHU Lei YANG Renchao SHEN Kun YANG Deping MAO guangzhou LI Min LIU Pengrui MA Xiaodong Shandong Provincial Key Laboratory of Depositional Mineralization and Sedimentary Minerals Shandong University of Science and TechnologyQingdaoShandong 266590China Key Laboratory of Gold Mineralization Processes and Resource Utilization MNR/Key Laboratory of Metallogenic Geological Processes and Resource UtilizationShandong Province/Shandong Institute of Geological SciencesJinan 250013China Laboratory for Marine Mineral Resources Qingdao Marine Science and Technology CenterQingdaoShandong 266237China

The Wangjiazhuang Cu(-Mo)deposit,located within the Zouping volcanic basin in western Shandong Province,china,is unique in this area for having an economic *** order to expound the metallogenetic characteristics of this porphyry-like hydrothermal deposit,a detailed fluid inclusion study has been conducted,employing the techniques of representative sampling,fluid inclusion petrography,microthermometry,Raman spectroscopy,LA-ICP-MS analysis of single fluid inclusions,as well as cathode fluorescence spectrometer analysis of host mineral *** deposit contains mainly two types of orebodies,***-dissemination-stockwork orebodies in the K-Si alteration zone and pegmatiticquartz sulfide veins above *** addition,minor breccia ore occurs *** types of fluid inclusions in the deposit and altered quartz monzonite are identified:L-type one-or two-phase aqueous inclusions,V-type vapor-rich inclusions with V/L ratios greater than 50%-90%,D-type multiphase fluid inclusions containing daughter minerals or solids and S-type silicate-bearing fluid inclusions containing mainly muscovite and *** petrography and fluid inclusion study has revealed a three-stage mineralization process,driven by magmatic-hydrothermal fluid activity,as ***,a hydrothermal fluid,separated from the parent magma,infiltrated into the quartz monzonite,resulting in its extensive K-Si alteration,as indicated by silicate-bearing fluid inclusions trapped in altered quartz *** is followed by the early mineralization,the formation of quartz veinlets and dissemination-stockwork *** the main mineralization stage,due to the participation and mixing of meteoric groundwater with magmatic-sourced hydrothermal fluid,the cooling and phase separation caused deposition of metals from the hydrothermal *** a result,the pegmatitic-quartz sulfide-vein ores *** the late mineralization stage,decreasing fluid salinity led to the formation of L-type aqueous

关键词： fluid inclusions fluid immiscibility mineralization mechanisms Wangjiazhuang Cu(-Mo)deposit

Magnetic properties of Jiaxian red clay sequences from northern chinese Loess Plateau and its paleoclimatic significance

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Science china Earth sciences 2005年第8期48卷 1234-1245页

作者： QIANG Xiaoke, AN Zhisheng, LI Huamei, CHANG Hong & SONG Yougui 1. SKLLQG, institute of Earth Environment, chinese academy of sciences, Xi’an 710075, {2. 2. guangzhou institute of Geochemistry, chinese academy of sciences, guangzhou 510640, {2. chinese academy of {2. SKLLQG Institute of Earth Environment Xi’an China chinese academy of {2. Guangzhou Institute of Geochemistry Guangzhou China

Detailed rock magnetism investigation of the Jiaxian red clay sequences indicated that there are common magnetic mineralogy properties in red clay and loess-paleosol sequences from the chinese Loess Plateau as well as the marked properties of themselves, magnetic min-erals mainly with magnetite, maghemite, hematite, and possibly limonite/goethite contributing to the magnetic behavior. Meanwhile, it is found that the strong paleosol in red clay sequences has a lower coercivity and higher content of ultra-fine ferrimagnetic grains than that of the weak pa-leosol, which is similar to loess and paleosol in upper wucheng Loess sequences, and indicates that humid conditions and relatively strong pedogenesis play a significant role in the increase of ultra-fine magnetic minerals and transformation of the magnetic minerals. This suggests that, like Quaternary loess-paleosols, the change of characteristics of paleoclimatic conditions of the late Tertiary red clay deposits is fluctuant. In addition, the results of magnetic hysteresis properties show that the applied saturated field for samples from the Jiaxian red clay sequences is higher than that of the samples from eastern and {2.ern chinese Loess Plateau. It is obviously shown that there exist more hard magnetic minerals and relatively weak biochemical processes in the Jiaxian red clay sequences on northern chinese Loess Plateau. We conclude that the paleocli-matic environment is different between northern and eastern/{2.ern chinese Loess Plateau, and it should be more arid in northern chinese Loess Plateau.

关键词： northern chinese Loess Plateau, red clay, magnetic property, paleoclimatic significance.

PREPARATION AND PROPERTIES OF ETHYL-CYANOETHYL CELLULOSE/POLYACRYLIC ACID COMPOSITE FILMS WITH REFLECTION COLORS

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chinese Journal of Polymer Science 2001年第3期19卷 277-282页

作者： Yong Huang institute of chemistry,{2., Beijing 100080 china Laboratory of Cellulose and Lignocellulosics chemistry guangzhou institute of chemistry{2., guangzhou 510650, china 中科院化学所北京

Ethyl-cyanoethyl cellulose [(E-CE)C]/acrylic acid (AA) becomes a cholesteric liquid crystalline solution withvivid colors when the (E-CE)C concentration is 42.wt%～52.wt%. (E-CE)C/polyacrylic acid (PAA) composites withcholesteric structure were prepared by polymerzing AA in (E-CE)C/AA liquid crystalline solutions. The layers of orderedpolymer chains in the cholesteric phase were inclined during polymerization and the degree of the inclination depended onthe polymerization temperature and the concentration of the solution before polymerization. The cholesteric structure in thecomposites could not be changed when temperature was lower than 100℃. Cross-linking of the PAA in compositesimproved their water-resistance. The cholesteric order of the composites without cross-linking was destroyed when theywhere immersed in water. The color derived from the selective reflection of the cholesteric phase of the cross-linkedcomposites turned from blue to red after the composites absorbed water. The color of the composites could be returned to theoriginal one when the absorbed water was removed from the swollen composites.

关键词： Cholesteric structure Composites Selective reflection Liquid crystalline solutions

Ecology of the rehabilitation of vegetation on tropical coastal eroded land in Guangdong， china

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Journal of Environmental sciences 1995年第1期7卷 74-84页

作者： Yu Zuoyue Wang Zhuhao south china {2. of Botany, chinese academy of sciences,guangzhou 510650,china south china Inst of Botany Chinese Academy of Science Guangzhou China

ＥｃｏｌｏｇｙｏｆｔｈｅｒｅｈａｂｉｌｉｔａｔｉｏｎｏｆｖｅｇｅｔａｔｉｏｎｏｎｔｒｏｐｉｃａｌｃｏａｓｔａｌｅｒｏｄｅｄｌａｎｄｉｎＧｕａｎｇｄｏｎｇ，ＣｈｉｎａＹｕＺｕｏｙｕｅ；ＷａｎｇＺｈｕｈａｏＳｏｕｔｈＣｈ... 详细信息

ＥｃｏｌｏｇｙｏｆｔｈｅｒｅｈａｂｉｌｉｔａｔｉｏｎｏｆｖｅｇｅｔａｔｉｏｎｏｎｔｒｏｐｉｃａｌｃｏａｓｔａｌｅｒｏｄｅｄｌａｎｄｉｎＧｕａｎｇｄｏｎｇ，ＣｈｉｎａＹｕＺｕｏｙｕｅ；ＷａｎｇＺｈｕｈａｏＳｏｕｔｈＣｈｉｎａＩｎｓｔｉｔｕｔｅｏｆＢｏｔ...

关键词： tropics ereded land ecology of vegetation recovery.

A METHOD OF PREPARING SPHERICAL NANO-CRYSTAL CELLULOSE WITH MIXED CRYSTALLINE FORMS OF CELLULOSE Ⅰ AND Ⅱ

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chinese Journal of Polymer Science 2001年第3期19卷 291-296页

作者： Xiao-fang Li En-yong Ding Guo-kang Li Laboratory of Cellulose and Lignocellulosics chemistry, guangzhou {2. of chemistry, chinese academy of sciences, guangzhou 510650 china College of Material Science and Engineering south china university of technology, guangzhou 510641, china 中科院广州化学所广东广州

A new kind of nano-crysta cellulose (NCC) prepared from natural cotton fiber has been obtained by the method ofacid hydrolysis. Compared to most other nanophase materials that derive from inorganic materials, our products are preparedfrom natural cotton fibers. The products are of spherical shape with mixed crystal forms of cellulose I and II. The preparationconditions determine the properties of the products. Prior treatment is a critical procedure. The properties of the products arealso strongly affected by such conditions as the kinds of acids used, the ratio of the acid mixture, the acid concentration, theultrasonic agitation time and hydrolysis temperature. The number average molecular weight of NCC is determined by gelpermeation chromatography (GPC). The particle size and shape were determined by transmission electron microscopy(TEM). X-ray diffraction was used to detect the crystallinity and average crystallite size of the panicle.

关键词： Spherical nano-crystal cellulose Mixed crystal forms of cellulose Ⅰ and Ⅱ, Ultrasonic agitation

The Juancheng chondrite──A new meteorite falling recently in china

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chinese Science Bulletin 1998年第21期43卷 1834-1837页

作者： CHEN Yongheng 1,2. WANG Daode+2.and WANG Ruitian+31. Department of chemistry, guangzhou Normal {2., guangzhou 510400, china 2. guangzhou institute of Geochemistry, chinese academy of sciences, guangzhou 510640, china 3. Heze Bureau of Seismolo Department of chemistry Guangzhou Normal University Guangzhou China guangzhou institute of Geo{2. Chinese Academy of Sciences Guangzhou China Heze Bureau of Seismology Shandong Province Heze China

The Juancheng chondrite, a new meteorite falling recently in Juancheng County, Shandong Province, china, is classified as an H5 (S2. chondrite based on the compositions of olivine (Fa= 19.2. σ Fa=0.46) and low-Ca pyroxene (Fs=16.9, σ Fa=0.4). The plagioclase in the Juancheng chondrite is rich in CaO, indicating a relatively high metamorphic temperature the parent body underwent.

关键词： Juancheng ordinary chondrite new meteorite.

Summary of the 11th Conference on Magnetic Confined Fusion Theory and Simulation

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Plasma Science and technology 2024年第10期26卷 1-7页

作者： guangzhou HAO Jianqiang XU Youwen SUN Zhibin GUO Organizing Committee of the 11th Conference on Magnetic Confined Fusion Theory and Simulation southwestern institute of Physics Chengdu 610041People’s Republic of China institute of Plasma Physics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031People’s Republic of China State Key Laboratory of Nuclear Physics and technology Fusion Simulation CenterSchool of PhysicsPeking UniversityBeijing 100871People’s Republic of China 不详

This conference report summarizes recent progress in plasma theory and simulation that was presented in contributed papers and discussions at the 11th Conference on Magnetic Confined Fusion Theory and Simulation(CMCFTS)held in Chengdu,china,2.–30 October,*** in various fields has been *** example,results on zonal flow generation by mode coupling,simulations of the key physics of divertor detachment,energetic particle effects on magnetohydrodynamic(MHD)modes in addition to ion-and electron-scale turbulence,physics of edge coherent modes and edge-localized modes,and the optimization of ion heating schemes as well as confinement scenarios using advanced integrated modeling are presented at the *** this conference,the scientific research groups were organized into six categories:(a)edge and divertor physics;(b)impurity,heating,and current drive;(c)energetic particle physics;(d)turbulent transport;(e)MHD instability;and(f)integrated modeling and code development.A summary of the highlighted progress in these working groups is presented.

关键词： magnetic confined fusion(MCF) theory and simulation modeling tokamak

The biomarkers of 2.6,10,15, 19-pentamethylicosenes and their carbon isotopic composition in the sediments from the Gulf of Mexico

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chinese Science Bulletin 2006年第14期51卷 1736-1740页

作者： SONG Zhiguang1,2.& WANG Cuiping1,31. State Key Laboratory of Organic Geochemistry, guangzhou {2. of Geochemistry, chinese academy of sciences, guangzhou 510640, china 2. guangzhou Research Center of Gas Hydrate, chinese academy of sciences, guangzhou 510640, china 3. Graduate School of chinese academy of sciences, Beijing 100039, china State Key Laboratory of Organic Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China guangzhou Research Center of Gas Hydrate Chinese Academy of Sciences Guangzhou China Graduate School of chinese academy of sciences Beijing China

A group of 2.6,10,15,19-pentamethyli- cosenes (PMIΔ) containing 1―5 unsaturated double bonds has been identified in the sea floor sediments from the Gulf of Mexico at the Green Canyon 2.8 *** PMIΔ compounds are distributed between nC2. and nC2. on the mass chromatogram of aliphatic fraction. Their δ 13C values are very much depleted in 13C and in the range of ?86.7‰ to ?115.5‰, whereas the δ 13C values of companion n-alkanes range from ?2..4‰ to ?34.6‰. These unsaturated PMIΔ com-pounds are typical biomarkers derived from the an-aerobic oxidation of methane mediated by meth-ane-oxidizing archaeal bacteria and indicative of the gas seeps or even the occurrence of gas hydrates in the deep sea sediments.

关键词：生物标志墨西哥湾沉积物 PMIA 天然气水化物