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    10 May 2005, Volume 24 Issue 05
    Chlorophyll fluorescence characteristics of some coniferous and deciduous tree species under different irradiance
    HE Yanhong, TIAN Youliang, GUO Liansheng
    2005, (5):  467-472. 
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    Change characteristics of chlorophyll fluorescence,maximum quantum efficiency (ΦP) and the real quantum efficiency (PhiPSⅡ),and the adaptability of Pinus tabulaeformis,Populus alba cv.pyramidalis,Ulmus pumila,Platycladus orientalis,Hippophae rhamnoides,Fraxinus pennsylvanica and Picea meyeri were studied under different irradiance.The results showed that ΦP and PhiPSⅡ decreased with increasing light intensity.Light course of ΦP and PhiPSⅡ could be expressed with equation y=a+b(1-exp(-kx)),in which x and y represented light intensity and ΦP or PhiPSⅡ,respectively.ΦP showed linear increase with increasing PhiPSⅡ.The maximum quantum efficiency,turning point and minimum quantum efficiency of light course could be used to estimate the photosynthesis quantum efficiency of the tested species and their adaptability to strong light.The photosynthesis quantum efficiency of the tested species according to the maximum PhiPSⅡ decreased in order of Hippophae rhamnoides>Ulmus pumila>Populus alba cv.pyramidalis>Fraxinus pennsylvanica>Pinus tabulaeformis>Picea meyeri>Platycladus orientalis.The adaptation capability to strong light estimated from the light intensity of turning point of ΦP light course and minimum quantum efficiency was in order of Populus alba cv.pyramidalis>Ulmus pumila>Platycladus orientalis>Fraxinus pennsylvanica>Pinus tabulaeformis>Hippophae rhamnoides>Picea meyeri.The results accorded with the ecological characteristics of the tested plants.
    Analysis on transitional feature of Saihanba spermatophyte flora in Hebei Province
    WANG Qingsuo, LI Yuzhong, LU Duanzheng, LUO Juchun, FENG Zongwei
    2005, (5):  473-477. 
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    Saihanba is located in the forest-steppe ecotone in northern Hebei Province of China.The spermatophytes in Saihanba flora were abundant,which includes 75 families,318 genera and 713 species or varieties.According to the floristic geographic elements in Saihanba flora,the northern temperate,cosmopoltan and palaeo-temperate was to the 47.65%,15.36% and 14.11% of the total 313 spermatophyte genera respectively,while the others were rare.Based on plant life-form,the phanerophytes,chamaephytes,hemicryptophytes,geophytes and therophytes were 16.27%,1.54%,40.95%,25.39% and 15.85% of the total spermatophytes respectively in Saihanba region.Compared with the other five surrounding regions using the principal component method,Saihanba was an obvious forest-steppe transitional flora.The relationships of Saihanba flora with Songshan Mountain flora in the forest zone and Xilinhe River Basin flora in the steppe zone were closer than those with the other region floras.
    Effects of nocturnal low temperature on photosynthesis of seedlings of two coffee species
    GUO Yuhua, CAI Zhiquan, CAO Kunfang
    2005, (5):  478-482. 
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    To explore the effects of nocturnal low temperature on photosynthesis of Coffea liberica and Coffea arabica,the two dominant coffee species in Southern Yunnan,the potted seedlings were exposed to nocturnal low temperature (4℃) for 3 days and then recovered for another 3 days under ambient environment during the cool and foggy season of Xishuangbanna in 2003.The photosynthesis parameters and the content of H2O2 and MDA were measured in mature leaves of the two species.The results showed that after three day's nocturnal low temperature exposure,although thermal dissipation capacity (NPQ) and Car/Chl ratio increased,the net photosynthetic rate (Pn),stomatal conductance (Gs) and initial photochemical efficiency of photosystem II (Fv/Fm) at dawn decreased greatly in leaves of the two species,accompanied with the accumulation of H2O2 and MDA,which suggested that their photosynthetic apparatuses were destroyed,and both stomatal and non-stomatal limitation contributed to the decrease of net photosynthetic rate.There were no significant differences of photosynthetic ability between the two coffee species in normal conditions.But compared to C.liberica,C.arabica had less decrease of Pn and Fv/Fm,less accumulation of MDA after nocturnal low temperature exposure,and recovered more quickly than C.liberica.That means that C.arabica is more chilling-tolerant than C.liberica.The mechanism is related with its higher Car/Chl ratio,heat dissipation capacity and higher ability to recover.
    Relationship between species diversity and productivity in four types of alpine meadow plant communities
    WANG Changting, LONG Ruijun, WANG Qiji, JING Zengchun, DING Luming
    2005, (5):  483-487. 
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    The relationship between species diversity and ecosystem function is one of the core problems on biodiversity research.Productivity is an important modality of ecosystem function.The species diversity of natural communities is often strongly related to their productivity.The grassland is an important component of the terrestrial ecosystems and plays a significant role in the biodiversity and ecosystem function's study.The relationship between species diversity and productivity of natural communities were studied on four alpine meadow types.The results showed that the species diversity-productivity pattern was linearly increase in Kobresia pygmaca meadow,K.humlis meadow,Potentilla froticosa shrub,while there was no significant linear relationship in K.tibetica of swamp meadow,which indicated that the species diversity of natural community could influence the productivity.At the same time,different environmental resource and environmental heterogeneity contributes to the productivity as well,which form discrepant structural characteristics of community and distribution of species diversity.
    Service value of forest ecosystem at middle section on northern slope of Tianshan Mountain
    LI Haitao, XU Xuegong, XIAO Dunng
    2005, (5):  488-492. 
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    Employing methods of market price,shadow price,business accounting,proceeds and losing analysis,the value of forest ecosystem services at the middle section on the northern slope of Tianshan Mountain was calculated.The results showed that the total value,including direct and indirect,reached 632 million yuan,of which,43 016 million yuan was the output of wood products, 80 million yuan of tourism,240.565 million yuan of water holding,73.34 million yuan of soil conservation against erosion,49.51 million yuan of adjusting atmosphere component,67.152 million yuan of cleaning air,24 million yuan of tourism income,and 124.5 million yuan of mountainous meadow.
    Growing status and evaluation of seedling stages of grass on fly ash
    YUAN Ju, LIU Fang, ZHANG Weibing, LUO Haibo
    2005, (5):  493-496. 
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    Employing pot experiment without fertilizer,we studied the seedling of eight species of grass grown on fly ash,peat soil mixed with fly ash,sandy soil mixed with fly ash,peat soil and sandy soil.The results showed that fly ash was benefit to the growth of grass seedlings,including Trifoliun repens,T.pratense,Lolium perenne,Festuca arundinacea,and Dichondra repens.The seeds of lawn grass in the fly ash sprouted faster,with the seedling rate,seedling height,tillers better than those in the others.But the leaves were feeble with light colour at later seedling stage.The seed of Agrostis stolonifera in the fly ash sprouted slowly with a low seedling rate,while the seeds of Zoysia japonica and Festuca rubra could not sprout in fly ash.
    Population characteristics of Artemisia intramongolica at different successional stages
    LIU Huamin, PIAO Shunji, WANG Lixin, LIU Fang, WEN Yun, LIU Shigang
    2005, (5):  497-502. 
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    Artemisia intramongolica is an important semi-shrub in the Hunshandake Sandy land and it has degraded significantly in the desert succession series from shifting to fixed sandy land.In order to find out the vital reasons of its degradation,the bioecological features and its habitat characteristics of A.intramongolica were studied in shifting,semi-shifting,semi-fixed and fixed sandy lands.The results showed that there was no significant difference in soil moisture among the different plots and the layers of soil before raining period.With the sandy land fixation,the soil moisture in 0~5 cm surface layer increased gradually.After raining period,though the soil moisture among plots had no significant difference,the maximum of soil moisture all occured in 0~5 cm surface layer.The contents of soil organic material and total nitrogen in plots were significantly different,which showed increase trend with the sandy land fixing.Though there was no significant difference among ramets and modules,the characteristics which reflected the ecological functions of population,such as canopy extension,biomass and reproductive allocation,were significantly different in plots and showed decline trend with the sandy land fixing.On this condition,the compositive vigour index (CVI) for A.intramongolica population was put forward to analyze the correlation between its characteristics and soil factors.It showed that with the sandy land fixing,there were significant difference between CVI of different succession stages.Its value decreased from 0.63 of shifting sandy land to 0.38 of the fixed,which negatively correlated with the contents of soil organic material and total nitrogen.
    Climate suitability change of winter wheat in Henan Province
    QIAN Huaisui, JIAO Shixing, ZHAO Feng
    2005, (5):  503-507. 
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    Employing the climate suitability degree model,the annual climate suitability change was calculated.The results showed that the fluctuation of precipitation suitability was very strong while that of temperature and sunbeam is less strong,and their vibrating amplitude has become weaker and weaker since 1980s.In terms of the change trend,temperature,sunbeam and climate suitability degree in turn increased at the speed of 0.003/10yr,0.005/10yr and 0.006/10yr,while precipitation suitability degree decreased at the speed of 0.002/10yr.
    Relationships between canopy temperature and biological characters of wheat under drought conditions
    FENG Baili, GAO Xiaoli, ZHAO Lin, GAO Jinfeng, WANG Changfa, ZHANG Songwu
    2005, (5):  508-512. 
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    Based on the long-term observation of canopy temperature and biological characters of wheat,we discovered a kind of cold type wheat that can maintain a low canopy temperature.Under drought condition,its canopy temperature was continuously lower than that of control,especially during milk-filling stage.Many of its biological characters,such as chlorophyll content,net photosynthetic rate,soluble protein content and SOD activity etc,were superior to those of warm type wheat,which make it grow more efficiently under drought condition.The discovery is very important to the variety selection and is useful to improve wheat yield and quality in dry farmlands.
    Horizontal distribution of phytoplankton quantity and the correlation with the nutrients in culturing waters of Kaozhou Bay based on GIS
    CAI Wengui, LI Chunhou, LIN Qin, JIA Xiaoping, YANG Meilan, ZHANG Hanhua
    2005, (5):  513-517. 
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    Supported by GIS and SPSS,the horizontal distribution of phytoplankton quantity and its correlation with water nutrients during highstand and lowstand seasons in culturing waters of Kaozhou Bay were studied with data interpolation,correlation analysis and regression analysis methods.The results showed that during the highstand,the distribution of phytoplankton quantity was even with the dense area locating in the estuary of Jilong River,while during the lowstand,it varied greatly with the dense area occurring in the waters from the mouth of the bay to the north of Yanzhou Island,which showed an increasing tendency from the northwest to the mouth of the bay.Comparing the two survey seasons,the phytoplankton quantity during highstand was obviously higher than that in the lowstand.The correlations between phytoplankton quantity and inorganic nitrate or phosphate were not significant,while there was a significant correlation between phytoplankton quantity and silicate which showed positive during the lowstand and negative during the highstand.
    Growth factors of unialgal strain and axenic strain of Microcystis aeruginosa in Songhua Lake
    WANG Xia, LU Xianguo, ZHANG Xuelin, ZHANG Zhuqing
    2005, (5):  518-522. 
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    Employing capillary-pipette washing method,the unialgal strain and axenic strain of Microcystis aeruginosa from Songhua Lake were isolated and purified,and effects of temperature,illuminance,nitrogen,phosphorus,and iron on their growth were investigated.The results showed that there was no significant difference under the influences of temperature,illuminance,nitrogen,phosphorus,and iron on the maximum specific growth rate of the unialgal strain and axenic strain.It reaches the maxirnum specific growth rate under the conditions of 33 ℃ of temperature,5 000 Lx (2 000 Lx) of illuminance,1.2 mg·L-1 of NO3--N,0.06 mg·L-1 of PO43--P and 0.05 mg·L-1 (0.04 mg·L-1) of ferric citrate.With the increase of N,P and Fe concentrations,maximum growth of the unialgal strain was much higher than that of the axenic strain.Thus,it would be able to improve the growth of M.aeruginosa if the associated bacteria presented.In view of N,P and Fe concentrations and the conditions of temperature and illumination in Songhua Lake,there exist the conditions of water-bloom in somepart of Songhua Lake.
    Relationship between mineral salt contents of host trees and Kerria lacca
    CHEN Youqing, CHEN Xiaoming, LI Kun, SHI Lei, CHEN Zhiyong
    2005, (5):  523-527. 
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    With comparison and cluster analysis methods,the relationship between mineral salt contents of host trees and Kerria lacca was studied.The results showed that mineral salt contents of 7 different host trees and branches hosted by K.lacca or not were different significantly,which could be divided into 4 groups.Cluster analysis suggested that mineral salt contents of 7 host trees hosted by K.lacca could be divided into 7 kinds.There were some relationships between mineral salt contents of hosted branches and the thickness of raw lac,mortality,fecundity and secretion amount of K.lacca but not significant.Compared with control,the contents of nitrogen,phosphorus(P2O5) and iron in host branches of Schleichera oleosa decreased to different degrees,while that of sodium nearly had no change and that of potassium,calcium,magnesium,copper,zinc and manganese increased incoordinately,especially the calcium content,which was 5.3 times as that of the control branch.The mineral salts contents of the other host trees also increased or decreased.
    Seedrain of wild apricot and predation by small rodents
    LU Jiqi, LI Hongjun, ZHANG Zhibin
    2005, (5):  528-532. 
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    Wild apricot (Prunus armeniaca),a shrub-like small arbor,is distributed widely on sunny slopes of mountainous areas of Beijing,that survives well under dry conditions with poor soil or in deforested hills.Few studies had been done on the production and seed-rain,much less on the effect of consumption and removal by small rodents on dynamics of seed-bank.During July,2002 and July to September,2003,we estimated the production and seed-rain of wild apricot using collecting basket.The sample size was 16 and 20,in 2002 and 2003,respectively.The differences between consumed seeds and removed seeds within exclosure and ground quadrat,and the differences between exclosure and ground quadrat were compared.The results showed that the seed production of wild apricot varied significantly among years,and the peak of seeds falling occurred from late July to early August,among which the aborted seeds fell prior to the intact ones.There was significant difference between consumed and removed seeds both within exclosure and ground quadrat,which suggested that rodents tended to eat and transport seeds from the same sites.The difference of consumed seeds and removed seeds,respectively,between exclosure and ground qnadrat were not significant,which indicated that rodents were the main factor affecting the fate of seeds in seed-bank of wild apricot in the course of seed-rain,and the impact from birds was negligible.The percentage of seeds consumed and removed by rodents was low compared to the productivity.
    Control technologies on urban surface runoff pollution in China
    YIN Wei, LI Peijun, KE Xin, SU Dan, LI Haibo, GUO Wei
    2005, (5):  533-536. 
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    Urban surface runoff pollution with characteristics of extensive and random distribution and complex origination is a kind of typical non-point source pollution,which has become one of the important factors that aggravate water environment pollution.A control measure of urban surface runoff pollution was put forward in this paper,which included the treatment at pollution source,the control of pollutants during delivering and moving,and the sink treatment.Some specific technologies used to control,treat,and manage contamination were discussed among which effective interception of runoff should be focused on in the future.
    Research and application advances in leaf area index (LAI)
    WANG Xiqun, MA Luyi, JIA Zhongkui, XU Chengyang
    2005, (5):  537-541. 
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    This paper reviewed the research and application advances of leaf area index (LAI),which was put forward in 1947,in plant photosynthesis,transpiration and their connection,productivity forming,carbon,energy and water flux of forest-stands at landscape and regional scales,in the growth model of forest ecosystem,and in the study of energy and water exchange with remote sensing techniques.As an important physiological parameter of population and community growth analysis,LAI has been extensively applied in agriculture,horticulture,forestry,biology and ecology.
    Composition and vertical distribution of plant resources at the middle section on the northern slope of Tianshan Mountains
    FENG Ying, ZHANG Weidong, LI Xinjie
    2005, (5):  542-546. 
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    Based on field investigation and relative data,the composition of grassland plant resources at the middle section on the northern slope of Tianshan Mountain was analyzed.The results showed that the complicated ecological and geographical conditions resulted in abundan plant resources in this area,and the maximum of the species richness appeared in the alpine meadow.The heterogeneity of species along the vertical zone and the diversity of habitats at different parts could be reflected obviously by β index.The vertical differentiation of grassland species resulted from the habitat and environment evolvement.The conclusion could provide a scientific foundation to the conservation of biodiversity in this region.
    Quorum sensing in nitrogen-fixation rhizobia
    ZHENG Huiming, ZHONG Zengtao, CHEN Yi'nan, ZHU Jun
    2005, (5):  547-550. 
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    Bacteria can regulate gene expression by producing signal molecules termed autoinducers at high cell density.In general,Gram-negative nitrogen-fixation rhizobia use acylated homoserine lactones (acy1-HSLs) as autoinducers.Quorum sensing plays important roles in coordinating the symbiotic process during the interactions between rhizobia and their legume hosts.This review summarized the composition and regulation mechanisms of AHLs-mediated quorum sensing,physiological activity changes and symbiotic nitrogen-fixing effects caused by quorum sensing in rhizobia.
    Sensitivity of rocky desertification and its spatial distribution in southwestern China
    XIAO Rongbo, OUYANG Zhiyun, WANG Xiaoke, ZHAO Tongqian
    2005, (5):  551-554. 
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    Rocky desertification is one of the most serious eco-environmental problems.It is necessary to identify the most sensitive region and to offer scientific foundation to tackle rocky desertification.Based on the studies on rocky desertification and correlative eco-environmental problems,four leading factors,namely,lithology,precipitation,slope and vegetation were identified to be accountable for rocky desertification,with their influence on sensitivity classified.The integrated assessment of rocky desertification sensitivity in Southwestern China was proposed which could reflect the fact on the whole.The central,south and west of Guizhou,west and east of Guangxi,and east of Yunnan are the most sensitive areas to rocky desertification,while it is relatively less harmful in Sichuan and Chongqing.
    Economic effect analysis of climate protection policy based on increasing carbon sink
    ZHENG Yiping, WANG Zheng
    2005, (5):  555-560. 
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    At present,the climate protection policy based on increasing carbon sinks has become a hot point of the world.Then,how about its economic feasibility? This issue must be discussed within the general equilibrium of macroeconomic.Aiming at this question,this paper put forward a technical route to analyze the impact of the climate protection policy based on increasing carbon sinks on the economic security,and established a dynamic macroeconomic model for analysis.
    Review on bioremediation of immobile or slow surface waters with immobilized microbe techniques
    LI Haibo, LI Peijun, ZHANG Yi, JU Jingli, YIN Wei, GUO Wei, XU Huaxia
    2005, (5):  561-566. 
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    The remediation of contaminated surface water is a widely concerned environmental topic in recent years.Sometimes the conventional techniques cannot work effectively restricted by the waters' particularities.The technique of immobilized microbe,abbreviated IM,is becoming an important remediation method because of its significant advantages.It can not only provide a special microenvironment to protect dominant microbe from malignant competition of aboriginal microbe,but shield microbe from the environment.Base on the analysis of IM technical characteristics and its feasibility,some key techniques to be solved were put forward to remediate immobile or slow-flow urban surface waters with IM.
    Chemical defense of fruits (seeds) and the adaptive strategies of frugivorous animals
    LU Changhu
    2005, (5):  567-572. 
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    Seed plants should protect the fruits and seeds from predating by frugivores when fruits become ripe,and disperse the seeds to the habitat suitable for seed germination.The plants which rely on frugivores to finish seed dispersal are called animal-dispersed plants.Chemical defene of fruits (seeds) is an important way for plants to avoid seed predators.Various secondary substances exist in fruits and seeds including alkaloid,cyanogenic glycoside,terpenoid,and phenolic etc,with the content varied during the growth period of fruits.Secondary substances can defense the frugivores with general toxicity to both seed dispersers and seed predators.The pulp secondary substance can influence the dispersing efficiency by means of changing guts retention time acting as laxatives.The production of secondary substances not only depends on the environment factors of plants,but has some relationship with fruits quality.In temperate zone,content of secondary substances is low in summer small-seeded (SS) fruits,while high in fall low-quality (FL) fruits.Frugivores can adjust their foraging behavior,or get special substance from the environment or enough nutrients to reduce the influence of secondary substances.The research of secondary substances is important for the theory of animal-plant interaction and their coevolution.
    Advances in studies on dissolved organic nitrogen in terrestrial ecosystems
    LIU Yan, ZHOU guoyi, LIU Juxiu
    2005, (5):  573-577. 
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    Due to its active and effective character,dissolved organic nitrogen (DON) plays an important role in the terrestrial nitrogen cycle.The paper summarized the origin,property and flux of dissolved organic nitrogen in terrestrial ecosystems.Some suggestions for further study were put forward,which included,the assessment of hydrological process controls on the release and retention of DON in terrestrial ecosystems; quantification of sources and sinks of DON in terrestrial ecosystems; the ecological significance of DON in mineralization,immobilization,leaching and plant uptake process; differences in the dynamics of DON and DOC;and the relationship between DON and plant nutrition and carbon accumulation.
    Soil microbial biomass in degenerated and recovered grasslands of Huangfuchuan watershed
    SHAO Yuqin, AO Xiaolan, SONG Guobao, LIU Ruifeng, LI Hua
    2005, (5):  578-580,584. 
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    Soil microbial biomass was investigated in degenerated and recovered grasslands of Huangfuchuan watershed,in Inner Mongolia,China.The results showed that the vertical distribution of total soil microbial biomass in both degenerated and recovered grasslands was in order of 0~10>10~20>20~30>30~40>40~50 cm,which decreased with soil depths.Total bacteria and filamentous microbial biomass in 0~10cm were more than that in the other soil layers.Compared with the degenerated grassland,the biomass of soil microbial was higher in the recovered grassland.The distribution characteristics of soil microbial biomass in natural grassland was significantly related to soil fertility factors.The status of recovered grassland was superior to that of degenerated grassland,which meant that to recover grassland is the key measure to improve soil quality and to protect the ecological environment of Huangfuchuan watershed.
    Fractal properties of the spatial pattern of Alsophila spinulosa population in Mopangou,Fuling
    SHI Shengyou, GUO Qigao, CHENG Minghao, LIANG Guolu
    2005, (5):  581-584. 
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    Using box dimension of fractal theory,the fractal properties of spatial pattern of Alsophila spinulosa population in Mopangou,Fuling were studied.The results showed that distribution pattern of Alsophila spinulosa population possessed fractal properties.At different altitudes,the box dimension of the horizontal distribution patterns of Alsophila spinulosa populations was different,which closely related to the environmental factors.The box-counting dimensions of Alsophila spinulosa population in six community-types was in order of Symplocos laurina-Lophatherum gracile> Engelhardtia roxburghiana-Debregeasia edulis > Rhus chinensis-Veronicastrum slenostachyum > Macaranga tanarius-Miscanthus sinensis > Quercus fabri-Cyperus compressus>Litsea mollis-Polygonum chinensis.The box dimension reflected the spatial occupation degree of the population.The box dimension of the clumped population was higher than that of the random population.
    An improved top-open chamber for research on effects of elevated CO2 on agricultural pests in field
    CHEN Fajun, GE Feng, SU Jianwei
    2005, (5):  585-590. 
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    An improved top-open chamber was designed to study the effects of elevated CO2 on the interactions across host plants,pests and their natural enemies.This system includes CO2 source,CO2-measure-control system and top-open chamber.The top-open chamber,consist of no-color and transparent grass (2.5-mm thickness) wall,iron frame and hollow pedestal (octagon),and ventilation (eight 0.235 m3-1 exhaust fans per side).It can automatically control CO2 concentrations.CO2 concentrations,temperature and relative humidity were all well distributed at horizontal and vertical in top-open chamber,which is similar to natural environment.It was perceived that the setup of this apparatus was reasonable,and the usage performance was stable.We suggested that the improved top-open chamber could be used to study the effect of concentration changes of some atmospheric components on agriculture and ecosystem.