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Pedosphere 2009年第6期19卷 799-807页

作者： JIN Zhao DONG Yun-She QI Yu-Chun M. DOMROES institute of Geographical sciences and Natural Resources research Chinese Academy of Sciences Beijing 100101 （China） State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi＇an 710075 （China） institute of Geography Mainz University Mainz 55099 （Germany）

Precipitation is the major driver of ecosystem functions and processes in semiarid and arid regions. In such waterlimited ecosystems, pulsed water inputs directly control the belowground processes through a series of soil drying and rewetting cycles. To investigate the effects of sporadic addition of water on soil CO2 effux, an artificial precipitation event （3.mm） was applied to a desert shrub ecosystem in the Mu Us Sand Land of the Ordos Plateau in china. Soil respiration rate increased 2.8 4.1 times immediately after adding water in the field, and then it returned to background level within 48 h. During the experiment, soil CO2 production was between 2 047.0 and 7 3.3.0 mg m^-2. In the shrubland, soil respiration responses showed spatial variations, having stronger pulse effects beneath the shrubs than in the interplant spaces. The spatial variation of the soil respiration responses was closely related with the heterogeneity of soil substrate availability. Apart from precipitation, soil organic carbon and total nitrogen pool were also identified as determinants of soil CO2 loss in desert ecosystems.

关键词： desert shrub ecosystem Mu Us sand land soil respiration response water addition

On the Generalized Theory of Atmospheric Particle Systems

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Advances in Atmospheric sciences 1995年第4期12卷 419-438页

作者： Liu Yangang (desert research institute, Atmospheric {3. Center, Reno, Nevada 89506-0220,USA) Atmospheric sciences Center Desert Research Institute Reno USA

Unification is both necessary and challenging for studying atmospheric particle systems, which are polydispersesystems containing particles of different sizes and shapes. A general framework is proposed to realize the first order generalization. Within this generalized framework, (1) atmospheric particle shapes are unified into self-similar fractals; (2) a self-similar particle is characterized by various power-law relationships; (3. by combining these power-law relationships for a single particle with Shannon's maximum entropy principle and some concepts in statistical mechanics, unified maximum likelihoood number size distributions are of the Weibull form for atmospheric particle systems. Frontier disciplines (e. g., scaling,fractal,chaos and hierarchy) are argued to provide potential 'tools' for such unification. Several new topics are raised for future research.

关键词： Unification Self-similarity,Power-law relationships,Fractals Shannon's entropy Maximum likelihood distribution

Effect of Nitrate on Root Development and Nitrogen Uptake of Suaeda physophora Under NaCl Salinity

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Pedosphere 2010年第4期20卷 536-544页

作者： YUAN Jun-Feng FENG Gu MA Hai-Yan TIAN Chang-Yan Key Laboratory of Oasis Ecology and desert Environment Xinjiang Institute of Ecology and Geography ChineseAcademy of Sciences Urumqi 830011 （China） Graduate-UniversitY of chinese academy of sciences Beijing 100039 （China） College of Resources and Environmental sciences China Agricultural University Beijing 100094 （China）

The effects of NaCl salinity and NO^-3.on growth, root morphology, and nitrogen uptake of a halophyte Suaeda physophora were evaluated in a factorial experiment with four concentrations of NaCl （1, 150, 3.0, and 450 mmol L^-1） and three NO^-3.levels （0.05, 5, and 10 mmol L^-1） in solution culture for 3. d. Addition of NO^-3.at 10 mmol L^-1 significantly improved the shoot （P 〈 0.001） and root （P 〈 0.001） growth and the promotive effect of NO^-3.was more pronounced on root dry weight despite the high NaCl concentration in the culture solution, leading to a significant increase in the root：shoot ratio （P 〈 0.01）. Lateral root length, but not primary root length, considerably increased with increasing NaCl salinity and NO^-3.levels （P 〈 0.001）, implying that Na^＋ and NO3.- in the culture solution simultaneously stimulated lateral root growth. Concentrations of Na^＋ in plant tissues were also significantly increased by higher NaCl treatments （P 〈 0.001）. At 10 mmol L^-1 NO^-3. the concentrations of NO^-3.and total nitrogen and nitrate reductase activities in the roots were remarkably reduced by increasing salinity （P 〈 0.001）, but were unaffected in the shoots. The results indicated that the fine lateral root development and effective nitrogen uptake of the shoots might contribute to high salt tolerance of S. physophora under adequate NO^-3.supply.

关键词： halophyte lateral roots nitrate reductase activity root morphology

Effects of soil-plant system change on ecohydrology during revegetation for mobile dune stabilization, chinese arid desert

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research in Cold and Arid Regions 2009年第3期1卷 230-237页

作者： HongLang Xiao, Juan Ren, XinRong Li Key Laboratory of Ecohydrology and River Basin Science, Shapotou desert research and Experiment Station, Cold and Arid Regions Environmental and Engineering research {3., chinese academy of sciences, lanzhou, Gansu 730000, china. chinese Acad Sci Cold & Arid Reg Environm & Engn Res Inst Key Lab Ecohydrol & River Basin Sci Shapotou Desert Res & Expt Stn Lanzhou 730000 Gansu Peoples R China

Soil-plant systems play an important role in sand fixing and surface protection in the arid desert of china. This study examines the ecohydrological responses after a soil-plant system change for mobile dune stabilization by using a series of soil hydrological experiments and ecological investigation. The study results showed that decades of succession of soil-plant system has endangered the stability of the protection system. With the accumulated water and nutrient, a bio-logical system develops in a thinner and thinner surface soil. Redistribution of precipitation has changed completely in the ecosystem. In 3.15 mm of soil, a high capacity of crust water retention ultimately limits most rainfall from infiltrating below 10–20 cm deep. When that takes place, lower plants begin to compete for water with grasses and shrubs. A drought horizon forms in 20–500 cm depth with shrub transpiration. Artificial shrubs with deep roots obtain hardly rainfall supply and are gradually eliminated from the protection system. All changes in water environment affect the structure and func-tion and stabilization of whole protection systems. It is necessary to establish a relatively stable water environment by managing the soil-plant system for constructing a sustainable protective system in arid desert.

关键词： drought layer ecohydrology soil-plant system water cycle

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内蒙古后山地区土壤风蚀问题初论

土壤侵蚀与水土保持学报 1997年第2期3卷 84-90页

作者：董治宝陈广庭中国科学院兰州沙漠研究所

内蒙古后山地区的风蚀景观表明，该区的土壤风蚀是一个历史悠久的环境问题。实地调查表明，该区强烈的风蚀始于５０年代末和６０年代初。农田与草原的现状风蚀量之差异说明，土地开垦是导致该区土壤风蚀加剧的主要原因。应用粒度对比分... 详细信息

内蒙古后山地区的风蚀景观表明，该区的土壤风蚀是一个历史悠久的环境问题。实地调查表明，该区强烈的风蚀始于５０年代末和６０年代初。农田与草原的现状风蚀量之差异说明，土地开垦是导致该区土壤风蚀加剧的主要原因。应用粒度对比分析法对本区现状土壤风蚀量的计算结果为，草原平均５ｃｍ，农田一般在１０ｃｍ以上。若将农田与草原现状风蚀量之差视为草原开垦以后的农田风蚀量，并以５０年作为该区农田的平均开垦年限，可以计算出内蒙古后山地区草原农垦区近５０年的平均年风蚀厚度为０．１～０．３ｃｍ，风蚀模数约为１５００～４５００ｔ／（ｋｍ２·ａ），平均为３０００ｔ／（ｋｍ２·ａ）。因此，该区属于强烈土壤风蚀区。

关键词：内蒙古后山地区风蚀景观土壤风蚀量农田土壤风蚀模数草原粒度对比分析法

research ON AERODYNAMIC ROUGHNESS

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RESEARCH ON AERODYNAMIC ROUGHNESS

Relationship between the Malan Loess and the Salawusu Formation in the Salawusu River Area,Ordos,and Their Geological Ages

庆祝中国力学学会成立50周年暨中国力学学会学术大会’2007

作者： MU Qingsong~(*,+) MIAO Tiande~* DONG Zhibao~+ *(Department of Mechanics,School of Civil engineering and Mechanics,lanzhou University,lanzhou 730000,{3.) +(Key Laboratory of desert & desertification,Cold and Arid Regions Environmental and Engineering research institute,chinese academy of sciences,lanzhou 730000,{3.)

Theoretical analysis and numerical simulation are used to explain important experimental *** examples,when the wind velocity above the boundary layer increases,the aerodynamic roughness length decreases nonlinearly wi... 详细信息

关键词： wind velocity roughness length shear velocity displacement height geometric shape of roughness elements Nikuradse’s hydro-dynamical theory of roughness

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Acta Geologica Sinica(English Edition) 1988年第1期1卷 29-43页

作者： Li Baosheng Dong Guangrong Gao Shangyu Shao Yajun lanzhou desert research {3., Academia Sinica lanzhou desert research {3. Academia Sinica

In the middle and lower reaches of the Salawusu River. the Salawusu Formation regarded traditionallyas fluvio-lacustrine deposits actually includes a series of strata which mainly consist of eolian sandy depositsnamed as "Chengchuan Formation" by the authors. The eolian sand of the Chengchuan Formation and theMalan loess distributed in the upper reaches of the Salawusu River are deposits of sand and loess faciesformed by wind action during the same period. The relationship of the Chengchuan Formation and theMalan Loess with the Salawusu Formation which is really of fluvio-lacustrine deposits is that the formertwo superpose the latter. This can be demonstrated by the difference of the extinct species proportion of thefaunas in different strata. In this area. the Salawusu formed during the early period of Late *** the Malan Loess and the Chengchuan Formation deposited during the late period of the LatePleistocene.

关键词： Relationship between the Malan Loess and the Salawusu Formation in the Salawusu River Area,Ordos,and Their Geological Ages

A preliminary study on ecological waterdemand estimation in the arid region─A case in the Qaidam Basin

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Journal of Geographical sciences 1999年第2期9卷 155-162页

作者： ZHANG Xing-you SHEN Yuan-cun (institute of Geography, chinese academy of sciences, Beijing 100101, china)

The paper emphasized the relationship between environment and water taking ecological demand water (EWD) in the Qaidam Basin─an inner basin in northwestern china, as a key issue to discuss based on landscape umpping. First of all. the spatial heterogeneity of ecosystem can be reflected well by landscape pattern; secondly, landscape patterns adjust closely with environmental changes; finally, water condition is the key ecological factor for landscape pattern in the arid *** landsat TM image of 1:100,000 on September 22, 1996 were calibrated with topographical map of the same scale, and then landscape patterns were interpreted and mapped. As a result the Qaidam Basin could be divided into 14 main types, including 67 subtypes. Concerning the characteristics of the EWD of each sub-type, the EWD in the whole basin could be estimated according to the following formula:V= (E - P ) * S = r (KEo - P ) * S Where, V is the ecological demand for Water (m3., E is the evaporation potential on terrestrial surface (m). P is the precipitation in landscape unit (m), S is the area of landscape unit (m2), Eo is the evaporation potential on water surface (m), K is the evaporation coefficient, and r is the *** to the results, the ecological demand for water of desert vegetation is about 9,65×108m3. while it is about 24.48×108m3.for the lake in the inner basin. Therefore, the total EWD occupies approximately 65.7％ of the total water resources in the basin. In conclusion, the quantitative method based on landscape ecological mapping is feasible, which attentively transfers the 'point'information to the 'area'. However, the preliminary results are expccted to improve by further field delta.

关键词： the Qaidam Basin ecological water demand landscape pattern

Influence of environmental,root,and stand parameters on soil surface CO_2 efflux in a Populus euphratica of desert forest in extreme arid region

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research in Cold and Arid Regions 2009年第4期1卷 348-355页

作者： ZongQiang Chang,Qi Feng,YongHong Su,JianHua Si, HaiYang Xi,ShengKui Cao,Rui Guo Alashan desert Eco-Hydrology Experimental research Station,Cold and Arid Regions Environmental and Engineering research {3.,chinese academy of sciences,lanzhou 730000,china. chinese Acad Sci Cold & Arid Reg Environm & Engn Res Inst Alashan Desert Eco Hydrol Expt Res Stn Lanzhou 730000 Peoples R China

Spatial variation in soil surface CO2 efflux was measured in a stand of Populus euphratica in the Ejina Oasis of desert riparian forest in the extreme arid region in northwestern china from April 2007 through October *** were taken with a gas-exchange analyzer linked to a soil-respiration *** mean soil CO2 efflux in the stand was 2.71 μmol/(m2·s) during the growing season and 1.3. μmol/(m2·s) in the nongrowing *** seasonal maximum (end of May through early June) andminimum (October) CO2 efflux were 3.3. and 0.69 μmol/(m2·s),*** diurnal fluctuation of CO2 efflux was relatively small (3.) and soil moisture (R2=0.213..When all variables were considered simultaneously,only soil temperature (R2=0.3.8),soil moisture (R2=0.147),and root volume density (R2=0.021) explained a significant amount of variance in soil surface CO2 *** volumes were not correlated with soil CO2 efflux on our sites.

关键词： soil surface CO2 efflux Populus euphratica Oliv parameters Ejina Oasis

Novel Terpenoid Constituent from the Whole Plant of Lappula anocarpa C. J. Wang

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Novel Terpenoid Constituent from the Whole Plant of Lappula ...