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额济纳绿洲土壤养分的空间异质性

生态学杂志 2009年第12期28卷 2600-2606页

作者：司建华冯起鱼腾飞常宗强席海洋苏永红中国科学院寒区旱区环境与工程研究所阿拉善荒漠生态水文试验研究站兰州730000 兰州大学资源与环境科学学院兰州730000

利用地统计学方法研究了额济纳绿洲土壤有机质、全氮、全磷、全钾的空间异质性。结果表明:土壤养分含量分布均有较大的空间异质性,土壤有机质的理论模型为指数模型,全氮、全磷和全钾的理论模型均为球状模型;额济纳绿洲土壤有机质、全氮... 详细信息

利用地统计学方法研究了额济纳绿洲土壤有机质、全氮、全磷、全钾的空间异质性。结果表明:土壤养分含量分布均有较大的空间异质性,土壤有机质的理论模型为指数模型,全氮、全磷和全钾的理论模型均为球状模型;额济纳绿洲土壤有机质、全氮、全钾主要受结构性因子的影响,全磷受结构性因子和随机因子的共同影响;全氮、全磷和全钾的变程在7.68～7.86km,土壤有机质的变程较小,为5.4km。土壤养分的空间分布表现为南北高,中间低的分布格局。

关键词：土壤养分空间异质性地统计学 GIS 额济纳绿洲

ESR DATING OF THE CENOZOIC STRATA AT LAOJUNMIAO SECTION, YUMEN AND ITS SIGNIFICANCE FOR UPLIFT OF TIBETAN PLATEAU

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地学前缘 2000年第S1期7卷 226-226页

作者： Shi Zhengtao 1 , Ye Yuguan 2, Zhao Zhijun 1, Fang Xiaomin 1, Li Jijun 1 (1 school of resources and environment school, lanzhou university, lanzhou 730000,china 2 Institute of Marine Geology, Ministry of National Land resources, Qingdao 266071

Vast thickness gravel formation developed widely around Tibetan Plateau, it provides the evidences of the uplift strongly process of Tibetan Plateau and it is also the products of uplift. So the study on origin, sediment environment and deposit faces of gravel layers can reveal the process and feature of Tibetan Plateau. According texture and components and glue degree and lithostratigraphy context of gravels, these gravel layers were divided into lower Pleistocene Yumen gravel formation and Middle Pleistocene Jiuquan gravel formation by Prof. Sun Jianchu in 1942. Since then, a lot of works have been carried including magnetic chronology. However, the absolute accumulated age of gravel is not yet identical because of different methods and precision. In this paper, a 1000m thick Cenozoic sediment at Laojunmiao, located at the northern foothill of Qilian Mt., is dating for ESR systematically. 19 block samples were collected for ESR dating. The pretreated samples were irradiated with a 60 Co\|source in different dosage. The irradiated samples were kept untouched for about ten days and then measured with a JES\|FEIXG ESR spectrum with the following measurement conditions: room temperature, X\|band, Microwave power: 0 1mW and 2mW, modulation amplitude: 0 8mT, magnetic field scanning range (334±5)mT. We select Ge and E’ centre as the dating signal. The concentrations of radioactive elements, U, Th, K 2O, were determined by laser fluorescence, colorimetric spectrophotometry and atomic absorption techniques, respectively. AD value were obtained by linear regression. The results show that it is linear relationship between age and depth (thickness), and the age is well identical with paleomagnetic age.

关键词： gravel accumulation ESR dating uplift of Tibet plateau

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金川矿区地应力场特征

天津城市建设学院学报 2002年第2期8卷 81-85页

作者：刘高韩文峰聂德新兰州大学资源环境学院甘肃兰州730000 天津城市建设学院土木工程系天津300384 成都理工大学土木工程与环境学院四川成都610059

从地质构造、显微构造、地壳形变场和震机制解等方面 ,探讨了金川矿区区域应力场特征及其力源 .地应力测量成果综合表明 ,金川矿区为一以水平残余构造应力为主的高地应力区 ,地应力场具有显著的不均匀性、各向异性。

关键词：金川矿石地应力场高地应力地下工程稳定性

THE SAND WEDGE AND MIRABILITE OFTHE LAST ICE AGE AND THEIR PALEOCLIMATICSIGNIFICANCE IN HEXI CORRIDOR

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Chinese Geographical Science 2001年第1期11卷 80-86页

作者： HU Gang, WANG Nai-ang (school of resources and environment, lanzhou university, lanzhou 730000, P. R. china Cold and Arid Regrons environment and Engineering Research Institute, the Chinese Academy of Scienes, lanzhou 730000, P. R. china) school of resources and environment Lanzhou University Lanzhou P. R. China Cold and Arid Regrons environment and Engineering Research Institute the Chinese Academy of Sciences Lanzhou P. R. China

The sand wedges in Hexi Corridor occur in the alluvial gravel stratum of bajada and high terraces. The 14C ages of eolian sand in sand wedges prove that they formed during the Last Ice Age, with the mean annual air temperature about ? 5.6°C. The common 14C and AMS 14C dating ages of terrestrial branch relicts in Huahai clay-mirabilite interlayer are (11 600 ± 280) a B. P. and (1118 ± 54) a B. P. respectively, proving that the mirabilite formed at the cold episode of the Last Glacial Maximum(LGM) and Younger Dryers(YD) in Huahai Lake. It is pointed out that the mean annual air temperature in Hexi Corridor during LGM was about ?3°C – ?7°C, 11°C – 15°C lower than that of present, and that during YD was about 0°C – 2°C, 6°C – 8°C lower than at present. This decreasing temperature values are generally coincident with those inferred by pollen, sand wedge and ice core in the northern china, and also with the research on temperature-falling amplitude of middle and high latitude on the Northern Hemisphere recently.

关键词： sand wedge Last Ice Age Hexi Corridor paleoclimate

Characteristics and origins of primary fluids and noble gases in mantle-derived minerals from the Yishu area,Shandong Province,china

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Science china Earth Sciences 2006年第1期49卷 77-87页

作者： MA Jinlong1,2, TAO Mingxin2,3 & YE Xianren2 1. resources and environmental school, lanzhou university, lanzhou 730000, china 2. Key Laboratory of Gas Geochemistry, Institute of Geology and Geophysics, Chinese Academy of Sciences, lanzhou 730000, china 3. College of resources Science & Technology, Beijing Normal university, Beijing 100875, china resources and environmental school Lanzhou University Lanzhou China Key Laboratory of Gas Geochemistry Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou China College of resources Science & Technology Beijing Normal University Beijing China

Fluids and noble gases of mantle-derived materials are important tracers forthe mantle information. Compositions of primary fluids and noble gases in mantle-derived mineralsfrom the Yishu area, Shandong Province, china, were tested by the methods of heat-bursting andheat-melting respectively. The fluids are mainly composed of CO_2, CO and H_2, which account forabout 90% of the total, and are similar to the mantle-derived rocks from other areas of easternchina; ratios of ~3He/~4He in almost all samples range from 0.82 Ra to 2.74 Ra, whereas^(40)Ar/^(36)Ar from 299.5 to 758.8. Both ranges are much lower than those of the typical oceanmantle-derived samples (such as MORB) and primarily reflect the influences of the atmosphericcomponents and the radiogenic isotopes. Ratios of C/~3He range from 27.6 x 10~9 to 1050 x 10~9,N_2/Ar from 927 to 56612, and N_2/~3He from 2.5 x 10~9 to 27 x 10~9, similar to those in westernUnited States and New Zealand which belong to the tectonic plate collision regions. The ratios fallin the intersect of mantle-crust-atmosphere in the comprehensive tracer-charts, reflecting theinfluences of the atmosphere and the crusts with organic components. Our results suggest that thecomposition of the primary fluids and the isotopic ratios of the noble gases may either reflect theevolution process of mantle-derived rocks connected with the rise and eruption of magma, or theinfluence of the ancient subduction-plate on the continental mantle of this region.

关键词： noble gases, primary fluids, mantle-derived minerals, Yishu area.

Impact of land-use change on hydrological processes in the Maying River basin, china

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Science china Earth Sciences 2006年第10期49卷 1098-1110页

作者： WANG Genxu1,3, ZHANG Yu2, LIU Guimin2 & CHEN Lin3 1. Institute of Mountain Hazards and environment, Chinese Academy of Sciences, Chengdu 610041, china 2. Cold and Arid Regions environmental and Engineering Research Institute, Chinese Academy of Sciences, lanzhou 730000, china 3. Resource and environment school, lanzhou university, lanzhou 730000, china Institute of Mountain Hazards and environment Chinese Academy of Sciences Chengdu China Resource and environment school Lanzhou University Lanzhou China Cold and Arid Regions environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China

Since the 1960s, dramatic changes have taken place in land-use patterns characterized by the persistent expansion of cultivated land and a continuous decrease in natural woodland and grassland in the arid inland river basins of china. It is very important to assess the effects of such land-use changes on the hydrological processes so vital for water resource management and sustainable development on the catchment scale. The Maying River catchment, a typical arid inland watershed located in the middle of the Hexi Corridor in northwest china, was the site chosen to investigate the hydrological responses to land-use changes. The annual runoff, base flow, maximum peak flow, and typical seasonal runoff in both spring and autumn flood periods were selected as the variables in the hydrological processes. Statistical-trend analysis and curvilinear regression were utilized to detect the trends in hydrological variables while eliminating the climatic influence. The relationship between cultivated land-use and hydrological variables was analyzed based on four periods of land-use variation data collected since 1965. A runoff model was established composed of two factors, i.e., cultivated land use and precipitation. The impact of land use changes, especially in the large ar- eas of upstream woodland and grassland turned into cultivated lands since 1967, has resulted in a mean annual runoff decrease of 28.12%, a base flow decline of 35.32%, a drop in the maximum peak discharge of 35.77%, and mean discharge decreases in spring and autumn of 36.05% and 24.87% respectively, of which the contribution of cultivated land expansion to the influence of annual runoff amounts to 77%-80%, with the contribution to the influence of spring discharge being 73%-81%, and that to the influence of base flow reaching 62%-65%. Thus, a rational regulation policy of land use patterns is vitally important to the sustainable use of water resources and the proper development of the entire catchment.

关键词： land-use change, arid inland river catchment, hydrological process, impact, Maying River.

Study on ground temperature change and characteristic response of engineering geology of permafrost along Qinghai-Tibet Railway

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Science china(Technological Sciences) 2003年第Z1期46卷 78-90页

作者： PAN Weidong, WANG Quancai, YU Shaoshui & ZHANG Xiaoyan Department of Mechanics, school of Physical Science and Technology, lanzhou university, lanzhou 730000, china Institute of Mountain Hazards and environment, Chinese Academy of Sciences and Ministry of Water resources, Chengdu 610041, china State Key Laboratory of Frozen Soil Engineering, Cold and Arid Regions environment and Engineering Research Institute, Chinese Academy of Sciences, lanzhou 730000, china Sichuan Provincial Communications Department, Chengdu 610041, china lanzhou Univ Dept Mech Sch Phys Sci & Technol Lanzhou 730000 Peoples R China Chinese Acad Sci Inst Mt Hazards & Environm Chengdu 610041 Peoples R China Minist Water resources Chengdu 610041 Peoples R China Chinese Acad Sci State Key Lab Frozen Soil Engn Cold & Arid Reg Environm & Engn Res Inst Lanzhou 730000 Peoples R China Sichuan Prov Commun Dept Chengdu 610041 Peoples R China

Along with the global warming in the recent scores of years, comparatively big changes have taken place in the weather and other environmental conditions of the permafrost area in the Qinghai-Tibet Plateau, and very big changes have also occurred in the engineering geological conditions of the permafrost area. Based on a large volume of field survey data, this paper discusses the regularities of horizontal and vertical distribution of permafrost, with its focus of analysis on the temperature change characteristics of the soil in different frozen-soil zones, as well as presents simulation analysis and research for the engineering geologic characteristic response changes that would occur in the future when the temperature of the frozen soil in different zones rises by 1 and 2.6℃ respectively, which will have a tremendous impact on the stability of constructional work.

关键词： Qinghai-Tibet Railway, permafrost, ground temperature, engineering geological characteristic.

Identification and Evolution of Groundwater Chemistry in the Ejin Sub-Basin of the Heihe River, Northwest china

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Pedosphere 2007年第3期17卷 331-342页

作者： SU Yong-Hong FENG Qi ZHU Gao-Feng SI Jian-Hua ZHANG Yan-Wu Cold and Arid Regions environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou730000 （China） school of Mathematics and Statistics Lanzhou University Lanzhou 730000 （China）

Hydro-chemical characteristics of groundwater and their changes as affected by human activities were studied in the Ejin Sub-Basin of the Inner Mongolia Autonomous Region, china, to understand the groundwater evolution, to identify the predominant geochemical processes taking place along the horizontal groundwater flow path, and to characterize anthropogenic factors affecting the groundwater environment based on previous data. The concentrations of major ions and total dissolved solids （TDS） in the groundwater showed a great variation, with 62.5% of the samples being brackish （TDS ≥ 1 000 mg L^-l）. The groundwater system showed a gradual hydro-chemical zonation composed of Na^＋ -HCO3^-, Na^＋ -Mg^2＋ -SO4 ^2 -Cl^-, and Na^＋ -Cl^-. The relationships among the dissolved species allowed identification of the origin of solutes and the processes that generated the observed water compositions. The dissolution of halite, dolomite, and 2- gypsum explained, in part, the presence of Na^＋, K^＋, Cl^-, SO^4 , and Ca^2＋, but other processes, such as mixing, Na^＋ exchange for Ca^2＋ and Mg^2＋, and calcite precipitation also contributed to the composition of water. Human activity, in particular large-scale water resources development associated with dramatic population growth in the last 50 years, has led to tremendous changes in the groundwater regime, which reflected in surface water runoff change, decline of groundwater table and degeneration of surface water and groundwater quality. Solving these largely anthropogenic problems requires concerted, massive and long-term efforts.

关键词： Ejin Sub-Basin groundwater quality Heihe River human impact water resources development

Pioneer organisms after F-F mass extinction in Dushan region,Guizhou Province,and their significance in establishing new ecosystem

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Science china Earth Sciences 2006年第5期49卷 449-460页

作者： WANG Yue1, 2, WANG Xunlian1 & SHI Xiaoying1 1. school of Earth Sciences and resources, china university of Geosciences, Beijing 100083, china 2. school of resources and environment, Guizhou university, Guiyang 550003, china school of Earth Sciences and resources China University of Geosciences Beijing China school of resources and environment Guizhou University Guiyang China

After mass extinctions, most areas became “ecologically barren areas” lacking or even without ecosystem over an extensive region. Studying the pioneer organisms and the reconstruction process of a new ecosystem in the “ecologically barren area” is very important for revealing the evo- lution after bio-mass extinctions. In the Dushan region, Guizhou Province, china, the trace fossils appeared and flourished evidently earlier than body fossils after Frasnian-Famennian (F-F) mass extinction. The pioneer organisms and pathfinders in the “ecologically barren areas” are the trace-makers that are deposit-feeders with relatively simple structure and conformation on or near the deposit surface. The trace-makers have undergone an evolutionary process that their trace structures changed from simple to complex, and their living and moving areas and spaces enlarged from linear to planar and then to three-dimension spaces. Those characters show that the ability of the trace-makers to deposits and their efficiency of looking for food have been enhanced gradually and that those trace-makers constructed gradually a base for the new ecosystem. This process is similar to that of the trace fossils near the Precambrian-Cambrian boundary. In the Dushan area, only the recovery intervals have been identified for the Famennian body fossils, with no eminent radiation interval recognizable due to the Devonian-Carboniferous (C-D) mass ex- tinction. However, both the recovery and radiation intervals may be clearly recognized in the Famen- nian trace fossils based on their conformation and diversity. The evolution and diversification of the trace fossils in the “ecologically barren area” is considered to have played a role of necessary foun- dation for the recovery of body fossils in the ecological chain. With the gradual disappearance of the unfavourable environment factors resulting in the F-F mass extinction, a new ecosystem was reconstructed in the “ecologically barren area” through a three-

关键词： pioneer organisms, reconstruction of ecosystem, trace fossils, F-F mass extinction, Later Devonian, Dushan region, Guizhou Province, china.