Table of Content

20 May 2009, Volume 45 Issue 3

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Driving Mechanism of Human Forces to Urban Ecological Water Requirementsin Bao’an, Shenzhen

MAO Xiaoling,TIAN Kun,LI Jingping,LI Tianhong,LIU Yongwei

2009, 45(3):  1046-1054. 

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The interruption of human with the urban ecosystems will change the land use structure dramatically and result in deterioration of environmental quality as well as the remarkable change of ecological water requirements. Based on the case study of Bao’an, Shenzhen, this paper presents the quantitative relationship between urban ecological water requirements (UEWR) and the characteristic index for land use structure (SI). The driving mechanism of human activitiesto the land use change and UEWR is studied by Partial Least Squares Regression model. The estimation results indicate the significant negative correlation between UEWR and SI. The human driving forces can explain 50 % ～90 % of the deviation of the land use, especially more than 90 % of the urban construction area and SI. The explanation ability of the same driving forces to the ecological water requirements are 60 % ～80 %. The coefficients of the regression model represent the weight of the driving forces, among which the population is of the most important contribution. Through the same human driving mechanism, the UEWR can be explained and predicted by the simple index of SI.

The Key Points in Design of Inhomogeneous Field MRI and Its Applications

ZU Donglin,SUN Chunfa,ZHAO Xuna,TANG Xin,LIU Wentao,GUI Zhiqian,CAO Xueming

2009, 45(3):  377-384. 

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For the inhomogeneous magnetic field MR imager, the polarization field is virtually uniform within horizontal degrees of freedom and decreases monotonically in a direction away from the surface. The authors describe the imaging principle, and present requirements and constraints by terms of key points of physical design such as 90° excitation pulse,180° refocused pulse, encoding manner and pulse sequences. In addition, it reveals that the echo time is restricted by the diffusion effect on signal amplitude due to the huge static field gradient. The data evaluated from diffusion not only restrict the usable TE, but also determine the strength of encoding gradient G_x, G_z and RF excitation field B₁ and virtually usable RF pulse. The time spent for scanning one slice of human brain and inability of covering whole brain prohibit such MR imager from surgical intervention. It indicates that the advantage of the unilateral MR imager is portable. It can be used for arbitrary large sample to render MRI analysis of surface-layer in a non-invasive manner.

Molecular Dynamics Study on the Irradiation-Induced Damage in SiC

HE Bin,XUE Jianming,ZOU Xueqing,WANG Yugang

2009, 45(3):  385-389. 

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Molecular dynamics（MD）simulation was performed to study the irradiation-induced damage defects in SiC sample. The empirical Tersoff potential was employed to describe the interaction between SiC atoms， and 10 keV Si and 200 keV Au were used as incident ions. The electronic energy loss of the incident ions was coupled to the target atoms based on the ion track model. The simulation results indicate that the electronic energy loss can increase the maximum number of the displaced atoms. However， it only has slight influence on the final defects number， which maintains the power-law dependence on the nuclear energy loss.

Study Bottomium Production and Polarization with CMS Experiment

LIU Lie,QIAN Sijin,YANG Zongchang

2009, 45(3):  371-376. 

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The authors introduces the measurement of bottomium production cross section， the method to extract polarization parameter and the calculation of trigger rate with the CMS (Compact Muon Solenoid) detector on LHC (Large Hadron Collider). The bottomium mass resolution， reconstruction efficiency and trigger rate are simulated using CMS software. The purpose of this study is to verify the NRQCD(Non-Relativistic Quantum Chromo Dynamics) factorization method by measuring the bottomium production cross section and polarization in the hadron collision at the unprecedented high energy.

Application of Microfluidic Chips to Bacterial Metapopulations Culture by Integrating Agarose Structure

LUO Xianjia,LUO Chunxiong,LIANG Shibo,WANG Mingcong,CHEN Yong,JI Hang,OUYANG Qi

2009, 45(3):  390-394. 

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This paper introduces the fabrication of microfluidic chips based on integrating the agarose structure and their application to bacterial culture. Two designs of microfluidic chips were devised. One was a chemostat in microfluidic chip， applied to the killing kinetics of cells. The microfluidic chip showed several advantages， measuring the data on-line， simplify the experimental manipulation and feasible output of tolerant cells. Therefore it holds potential for research of the killing kinetics of cells. The other had three different high micro-culture chambers and the bacterial population was measured by two ways-fluorescent intensity and OD value， by which more information about the bacterial population was acquired. The experiments indicated that the measuring tendency of bacterial growth by OD value was consistent with one by fluorescent intensity. There are other advantages in such microfluidic chip that it is easy to fabricate the microfluidic chips and the agarose confines bacteria in the chambers and cell nutrients are diffusible in agarose， which offer a good means to research the motile bacteria.

A Novel Scheme for Application-Dependent Testing of FPGAs

LIN Teng,FENG Jianhua,ZHAO Jianbing,WANG Yangyuan

2009, 45(3):  402-408. 

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A novel scheme for application-dependent testing of FPGAs (field_programmable gate arrays) is proposed. This scheme models a design configuration (DC) of an FPGA as a network of LUTs(look-up-tables), non-LUT logic gates, flip-flops and interconnects, and the stuck-at faults on the interconnects (SAFIs) and the functional faults on the used LUTs (FFLs) are targeted. Two alternative types of test configurations (TCs) are proposed to improve the coverage of SAFIs obtained by automatic test pattern generation (ATPG) tools, while TCs under which exhaustive testing can be performed on the used LUTs are used to detect the FFLs. Experimental results show that, for the seven largest ISCAS89 benchmarks, this scheme can obtain the coverage ranging from 86.82% to 99.16% for the SAFIs, and 100% coverage for the FFLs.

Comparative Embryology of Aerial and Subterranean Flowers of Amphicarpaea edgeworthii Benth. (Leguminosae)

SHAN Jinggang,ZHANG Yi,GENG Shilei,RAO Guangyuan

2009, 45(3):  395-401. 

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Amphicarpaea edgeworthii Benth. is an amphicarpic legume widespread in China， of which three types of flowers can be produced in the same individual： aerial chasmogamous flowers， aerial cleistogamous flowers， and subterranean cleistogamous flowers. The morphological and embryological characteristics of aerial and subterranean flowers were examined by light and scanning electronic microscopes. The anther of aerial chasmogamous flowers was 4-sporangiate， and of Glandular tapetum. Cytokinesis of microspore mother cells in meiosis was of the Successive type， and tetrads were tetradedral. The mature pollen grains were 2-celled. The ovule was biteguminous and crassinucellate. The development of embryo sac was of the Polygonum type. The embryogeny was of the Onagrad type， and endosperm development corresponded to the Nuclear type. The embryological characteristics of the subterranean flowers were quite similar to those of aerial chasmogamous flowers. The main differences from the latter were： the anther was 2-sporangiate； the meiosis of microspore mother cells was accompanied by the Simultaneous and Successive types， and tetrads were tetrahedral and isobilateral. Meanwhile， embryological data available in Papilionoideae plants were analyzed， and the phylogenetic position of A.edgeworthii was discussed.

The Research of Estimation Method for GPS C/N0

JIANG Junwei,DUAN Xiaohui,LIN Yang

2009, 45(3):  409-414. 

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In order to analyze and estimate the important technical parameter C/N_0, firstly, expatiations of two classical estimation methods VSM (variance summing method) and PRM(power ratio method) are put forward, which are based on the same GPS signal and noise expressions. The reason why the M parameter for PRM should be set that way is presented. A new estimation algorithm MVM(max frequency component divided variance method) is proposed. After that, it analyzes how the navigation data transition impacts on the three algorithms, and enhances the PRM method's immunity from the effects of navigation data transition. Finally, a comparative analysis to these three algorithms in accuracy and stability is provided.

Modeling and Optimizing of Carbon Nanotube Based CMOS Logic Circuit

WANG Hao,ZHANG Zhiyong,WANG Sheng,CHEN Qing

2009, 45(3):  415-420. 

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Carbon nanotube based CMOS (complementary metal-oxide-semiconductor) field effect transistor inverters were modeled through SPICE(simulation program with integrated ciruit emphasis) by using table-lookup model. Simulation results were verified by the experimental results and good agreement was achieved. The effects of supplied voltage and the threshold voltage to the power and the delay characteristics of the inverters were investigated by DC analysis and TRAN analysis, and optimum strategy was given. In addition, optimum strategies for NOR and NAND logic circuits were given by the simulation using the semi-empirical table-lookup model.

Analysis of the Effects of the Proactive Personality on Graduates' Career Decision-Making Self-Efficacy

SHANG Jiayin,GAN Yiqun

2009, 45(3):  548-554. 

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The present study revised the Chinese proactive personality scale and explored the effects of college graduates' proactive personality on their career decision-making self-efficacy(CDMSE), and the moderate role of the job hunting stress in the path. A sample of 120 graduates completed the preliminary back-translated Chinese version of proactive personality scale(PPS). Another sample of 196 graduates completed a battery of structured questionnaires including the final Chinese version of PPS, scale of CDMSE for university students and employ stress questionnaires for college seniors (ESQ). Reliability and validity of PPS were analyzed and a hierarchical regression analysis was processed to examine the moderate role of job hunting stress in the path between proactive personality and CDMSE. All psychometric indexes of the revised PPS were satisfying (the Cronbach α index were 0.86). Proactive personality is significantly associated with CDMSE, accounted for 15.3% of the total variance of CDMSE. The product of centered PPS and job hunting stress had significant contributions, accounted for 4.0% of the total variance of CDMSE.

Approximating 2-Connected k-Dominating Fault-Tolerant Virtual Backbone

FENG Wangsen,CHEN Ping,ZHANG Bei,MA Hao

2009, 45(3):  421-425. 

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Because of the inherent node (link) failures in wireless networks, virtual backbones should be fault-tolerant. Fault-tolerant virtual backbones were modeled as 2-connected k-dominating sets. An approximation algorithm was designed to find a 2-connected k-dominating virtual backbone in wireless ad-hoc networks by analyzing the properties of maximal independent sets in unit disk graphs and the block-cutvertex tree structure of connected graphs. The time complexity and the performance ratio of the algorithm were analyzed and proved to be a constant, respectively.

Design of AES Coprocessor Used on the Node of Wireless Sensor Network

LI Yuwen,ZHANG Xing,JIANG Anping

2009, 45(3):  426-430. 

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To design an AES coprocessor used on the mode of WSN(wireless sensor network), a method of reusing some given modules or other resources is presented. Also, a novel circuit of mixcolumn module is designed to reduce the whole area of the system. Some methods such as insulation of the operands, dynamic power management and optimization of coding are adopted to reduce the power consumption. The AES coprocessor on the node of WSN of this paper is integrated in Virtex4 FPGA, and meets all the requirements of WSN.

Seasonal Variations of Tropospheric NO₂ over Megalopolis in Eastern China Using Satellite Remote-Sensing Data and Chemistry-Transport Model

YUE Jie,LIN Yunping,DENG Zhaoze,ZHAO Chunsheng

2009, 45(3):  431-438. 

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Spatial distributions of tropospheric NO₂ over China and variations of tropospheric NO₂ for selected regions in China are studied using of satellite monitoring data (GOME and SCIAMACHY) from March 1996 to March 2008. Global Chemistry-Transport Model (MOART-2) simulation is carried out to reveal significant seasonal variations of tropospheric NO₂ over megalopolis areas in eastern China. Results show that: 1) Maximum distribution of tropospheric NO₂ lies in region of Beijing-Hebei-Tianjing, Yangtze Delta, Perl river delta. Obvious increasing trend can be seen over East China, with a yearly increasing rate of 0.9×1015cm_-2. 2) Becacuse of effective eliminating of NO₂ by OH, tropospheric NO₂ over megalopolis in East China shows significant seasonal variations: tropospheric NO₂ maximum appears in winter, and decreases sharply in summer. In background area West China where natural emissions dominates, tropospheric NO₂ shows reversed phenomenon compared to the East.

Temporal Variation in Volume Flux of Hawaii Plume through 35 Ma

HAN Shuoshuo,CHEN Yongshun

2009, 45(3):  444-450. 

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A flexure model is formulated to estimate mantle plume volume flux through hotspot swell topography. By using the model curve to best fit the actual seafloor topography on 27 cross-sections of Hawaiian swell, the temporal variation in volume flux of Hawaiian plume during the past 35 Ma is estimated, and two volume flux peaks at 3-4 Ma and 17-19 Ma before present are observed.

A Study on Determining Aerodynamic Parameters over Gobi Desert Surface

HE Yufei,ZHANG Hongsheng,LIU Mingxing,KANG Ling

2009, 45(3):  439-441. 

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A method is proposed for determining the surface roughness length. In order to obtain z_０, only the fine wind profile observation are required, thus the measurement errors can be quite low. This method is particular useful for circumstances when near-neutral conditions are rare in observation. Based on the atmospheric boundary layer observation over the Gobi desert area in Hexi Corridor, the roughness z_０ is estimated to be 0.60mm, close to the value of 0.78mm obtained by other method, which demonstrates the reliability of the authors' method. Besides, since observation at different height represent characteristics of different surface area, the height should be taken into account when determining the value of surface roughness.

A Study of Sublepidodendron in the Early Carboniferous of South China and Its Taxonomic Implication

CUI Li,WANG Deming

2009, 45(3):  451-460. 

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Sublepidodendron mirabile, S. songziense, correlative strobilus and rhizomorph are described from the Lower Carboniferous Gaolishan Formation in Linxiangxi Section, Ziqiu Town, Changyang County of Hubei Province. Morphology of leaf cushions of these two Sublepidodendron species are reinvestigated, and the whole-plant concept of Sublepidodendron is further confirmed. The biological features of S. mirabile, S. songziense and S. grabaui are compared in detail, the taxonomy of Sublepidodendron in China is discussed, and a new grouping scheme is proposed.

Fluctuations of Stable Carbon Isotopes around the Permian-Triassic Boundary in Huaying of Sichuan, South China: Its Characteristics and Biogeochemical Origin

CUI Ying,LIU Jianbo,EZAKI Yoichi

2009, 45(3):  461-471. 

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Detailed researches on the stable carbon isotopes at the Loufangwan Section, Huaying, Sichuan Province show the stable carbon isotopes has the similarities with many other Permian-Triassic records around the world. A larger mean value of Δ_B in earliest Triassic than that in latest Permian indicates increasing concentration of phosphate and bloom of primary producers in the ocean. Large volcanic eruption and enhanced weathering that began in the end of Permian were possible triggers for a slow decrease in δ¹³C_carb. Synchronously, quick decreases in δ¹³C_carb and δ¹³C_org in the earliest Triassic, indicating a global carbon cycle change, might be due to the main episode of the mass extinction and upwelling of anoxic deep-water masses during sea level rise. Therefore, the carbon isotopes profile around the Permian-Triassic boundary may reflect combined results of volcanic activity, sea level change, mass extinction of marine and land biomass decrease and anoxic water upwelling.

Mg-Carpholite Metapelite and Its Implications for Ancient Oceanic Subduction in the North Qilian Suture Zone, NW China

YU Xiaoning,SONG Shuguang,WEI Chunjing,ZHANG Lifei

2009, 45(3):  472-480. 

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A typical Early Paleozoic oceanic suture zone, which consists of ophiolite, arc volcanic rocks and high-pressure low-temperature metamorphic rocks, occurs in the North Qilian Mountains, Northwestern China. Eclogite facies metapelites with index mineral assemblage of Mg-carpholite + garnet + chloritoid + phengite were studied in details in petrology and mineralogy. Using THERMORCAL (V3.23), the authors calculated the P-T conditions of the stability field for Carpholite (cr) + garnet (g) + chloritoid (ct) + phengite (ph) assemblage at P=2.2-2.5GPa and T=530-580℃. Based on the calculated stability fields of carpholite and chloritoid, the authors confirmed that the North Qilian suture zone was a “cold" oceanic subduction zone in Early Paleozoic time with geothermal gradients of 6.5-7.5℃/km, similar to Mesozoic-Cenozoic subduction zones. This study plays an important role in understanding the thermo-structure of the Early Paleozoic subduction zones and dehydration of HP metamorphic pelitic rocks.

Concession of Tourism Operation in Nature Reserves with the Domination of Local Government: A Case Study

LIU Yining,LI Wenjun

2009, 45(3):  541-547. 

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Based on the case observation, this paper indentifies the important stakeholders in T Nature Reserve, and analyzes their behaviors. The authors argue that, although the management agency has the legal right to supervise and manage the tourism operating firm, it is hard to supervise and manage the tourism operating effectively to prevent the acts damaging environment because of the interference of local government. The reason why the management agency is obedient to the local government's interference is that local government is one of the most important financial sources of T Nature Reserve management agency and has the right to appoint personnel of T Nature Reserve management agency, and the reason why local governments interfere with the affairs of the management agency is that local officials will be devoted to economic development at local level in China now.

Logging Response to the Volcanic Cycles of the First Member of Yingcheng Formation in Xujiaweizi Fault Depression

ZHANG Liwei,SHI Yongmin,LI Jianghai

2009, 45(3):  481-487. 

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The volcanic rocks of the Yingcheng formation in the Songliao Basin were formed by multiple and intermittent eruptions. Based on the core drilling data, the high-resolution volcanic cycles of the first member of Yingcheng formation in Xujiaweizi fault depression were divided, the volcanic cycle model were built, and the well logging characteristics of different lithology and lithofacies were summarized. The results reveal that, the first member of Yingcheng formation could be divided into 3 volcanic cycles, from the top to the bottom of each cycle, the values of gamma-ray and resistivity were higher and higher, the amplitude and frequency of the well logs in the interface of different cycles changed greatly, indicating the existence of the weathering crust or the sedimentary layer. Logging data of gamma-ray, resistivity and density were considered to be more sensitive in recognition of different volcanic lithology and lithofacies.

Modeling the Dynamic Evolvement of Road Networks Based on Object Version Management Methods

LIU Yuefeng,LU Binbin,ZHANG Yibo,LIU Ting

2009, 45(3):  488-494. 

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A spatio-temporal data model is proposed to represent dynamic road networks based on Base State with Amendments model and object-version management theories. The network is considered to be comprised of road links and intersections, of which the evolution processes are studied respectively. Moreover, three operators on the objects: creation, deletion and update, as well as integrity constrains, are all discussed. On the basis above, a spatio-temporal data model is established and query algorithms are proposed. Database and query system are developed with the road networks data of Beijing. The status can not only be reflected, but also the historical states and evolution process can be described effectively in this model.

Relationships between the Types, Pattern Characteristics of Urban Green Space and Land Surface Temperature： A Case Study in Shenzhen Special Economic Zone

CHENG Haohao,ZENG Hui,WANG Zishu,JIAN Xia

2009, 45(3):  495-501. 

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This paper took Shenzhen Special Economic Zone as an example, using the TM and Quickbird images of Shenzhen in November 2005, and further inversion of surface temperature and manual interpretation of urban green space based on them, discussed the relationship between the types, attribute characteristics of urban green space and the spatial differentiation of urban thermal environment. The results show that the land surface temperature differed in green space types, and the artificial green space was generally higher than that of natural green space. Furthermore, the sample plots analysis in the research area revealed significant relationships among the selected indices. The HI index was positively correlated with the average NDVI index and the contagion index; besides, the HI index was negatively correlated with the average evenness index and the fragmentation index.Since the types, structure and pattern characteristics of urban green space could have significant influence on the spatial differentiation of urban thermal environment, more attention should be paid to the thermal impacts of urban green space in order to gain better ecological services.

Comparison of Cu/Zn/Pb Extraction from MSWI Fly Ash by Different Processes: Water Washing, Acid Washing and Water-Washing Combining Acid-Washing

ZHENG Liting,LIU Yangsheng

2009, 45(3):  502-510. 

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This study compared the extraction efficiencies of Cu, Zn and Pb from the fly ash of municipal solid waste incineration (MSWI) by three different processes: water washing, acid washing and wash+acid washing. XRD and SEM/EDS analysis were exploited to illustrate the variation of morphology, mineralogical and chemical composition for treated fly ash during different processes. Results show that the treatment of fly ash by water washing or acid washing can not separate Cu, Zn and Pb from fly ash. Meanwhile, the water washing process followed by the acid washing process can effectively extract Cu and Zn, and Pb will be kept in the residue. In this combining process, the acid-residue ratio is the key parameter for the metal extraction. The optimum process parameters for the metal extraction are water-washing (water/ash=3∶1) combining acid-washing (acid/ash=6∶1). Results of XRD analysis demonstrate that the water washing or acid washing process remove several kinds of soluble compounds and mineralogy phases are newly formed. Results of SEM/EDS analysis show that contents of Si and O in the residues will increase due to the solubility of salts and hydration of some oxide compounds.

Soil Dissolved Organic Carbon Decreased Following 40-year Grassland Afforestation

LIU Chang,REN Yanlin,HE Jinsheng

2009, 45(3):  511-518. 

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To determine the change of soil dissolved organic carbon (DOC) following grassland afforestation, the authors compared soil DOC, soil organic carbon (SOC) and soil total N (STN) of top 30cm soils under Leymus chinensis meadow steppe, Pinus sylvestris var. mongolica plantation, and Larix principis-rupprechtii. plantation in Saihanba, Hebei Province. DOC, SOC and STN of coniferous plantation soils were less than those of meadow steppe soils; DOC, SOC, and STN decreased following 40-year grassland afforestation. Soil heterogeneities of coniferous plantations were lower than meadow steppes.

Non-Structural Carbohydrate, N, and P Allocation Patterns of Two Temperate Tree Species in a Semi-Arid Region of Inner Mongolia

YIN Jingjing,GUO Dali,HE Siyuan,ZHANG Lei

2009, 45(3):  519-527. 

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To examine patterns of nutrient concentrations in different organs, stoichiometry of various nutrients, and the relation of nutrient concentrations with species and the environment, the concentrations of total non-structural carbohydrate (TNC), nitrogen (N), and phosphorus (P) among leaves, stems, tap roots, and first order roots in Asian white birch (Betula platyphylla) and Meyer spruce (Picea meyeri) were studied. The two species were located in the southeastern edge of Inner Mongolia. For TNC, leaves had the highest and first order roots had the lowest concentrations ; the largest difference between them was less than 53%. For N and P, however, there were much higher concentrations in leaves and first order roots than that in stems and the tap roots; the largest difference between them was about 98%. These patterns were determined by the physiological roles (carbohydrate production, nutrient uptake and storage, etc.) that different organs play. In addition, both TNC∶ N and TNC∶ P of Meyer spruce were higher than those of Asian whiter birch, reflecting the physiology of different species and variations in soil nutrient conditions.

Modeling the Grazing Behavior in Early and Intermediate Grassland Contract Stage and the Involved Ecological Compensation Mechanism

SONG Bo,XIN Yongliang,CAO Wentian

2009, 45(3):  528-532. 

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Understanding and regulating of the grazing behavior of local herdsman can be propitious to avoid overgrazing, which is regarded as the dominant driving force of grassland degradation. The grazing behavior in early and intermediate stage of grassland contract was analyzed by employing the model of growth and consumption in pasture system，into which the discount rate was introduced. The result shows that herdsmen like to maximize their grazing intensity in early grazing stage, no matter how perfect the institution of pasture property right is. However, in intermediate grazing stage, herdsmen will lower the grazing intensity, so they can keep green biomass stable at the economicial optimalizing level. The intermediate grazing intensity is positively related to the discount rate, and the economicial optimalizing green biomass is negatively related to the discount rate. Therefore, it is possible to keep the economicial optimalizing green biomass above a given threshold by paying herdsmen ecological compensation in theory. Particularly, the monetary value can be obtained by compensation coefficient times green biomass. In addition, compensation coefficient is positively related to the discount rate，and negatively related to the threshold.

Effects of Throughfall Manipulation on the Dynamics of Soil Microbial Biomass Carbon and Microbial Quotient in a Pinus sylvetris var. mongolica Plantation

WEI Tianfeng,REN Yanlin,ZENG Hui,HE Jinsheng

2009, 45(3):  533-540. 

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A field experiment manipulating throughfall was constructed in a Pinus sylvetris var. mongolica plantation at PKU-SOGES. This study investigated the response of two indicators of belowground ecosystem processes, soil microbial biomass carbon and microbial quotient, to±30% throughfall amount. During the growing season from May to September, 2007, soil microbial biomass carbon (260.7 mg/kg) and microbial quotient (1.84 %) decreased with soil depth. Generally, the effects of ±30% throughfall amount on the means of soil microbial biomass carbon and soil microbial quotient in the growing season were not significant. Interestingly, the dynamics were much clear for the -30% throughfall treatment, with soil microbial biomass ranged from 243.1 mg/kg to 354.3 mg/kg and microbial quotient from 1.43% to 2.16%, and the highest value was in May and the lowest was in July. This indicates that the decrease of precipitation in a growing season may lead to a stronger fluctuation in soil microbial activity, thus alter the dynamics of belowground carbon cycle processes.

A New Type of Chrysanthemum Stone

WANG Zhenghua,GUO Lishuang,GUO Guolin,HE Guojin,LI Jianhui,LIU Yulin

2009, 45(3):  555-558. 

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The new type of chrysanthemum with white ground and black pattern is of great value on ornament for its well distributed and more solid leaves. It occurs in the Altai of Xinjiang and is formed by steam-water hydrothermal process. The leaves are holmoustite and the ground is mainly mica schist. This type of chrysanthemum stone is more rigid and compact, and is convenience for collection.