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    15 July 2005, Volume 16 Issue 7
    Articles
    Tree species diversity of tropical montane rain forest in Xishuangbanna, Yunnan
    LI Zongshan 1,TANG Jianwei 1,ZHENG Zheng 1,ZHU Shengzhong 2 ,DUAN Wenyong 2,SONG Junping 2,GUO Xianming 2,ZENG Rong 2
    2005, 16(07):  1183-1188 . 
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    Tropical montane rain forest (TMR),one of the main forest vegetation types in Xishuangbanna of Yunnan Province,occurs horizontally in the north (TMRFⅠ) and vertically in the south (TMRFⅡ).In order to understand its tree species diversity in different zones,six fixed plots (50 m×50m) at different sites in Xishuangbanna were established,two (plots 1 and 2) for TMRF I,and four (plots 3,4,5 and 6) for TMRF II.Grid method (10 m×10 m) was used to record all the individuals with DBH greater than 2.0 cm in each plot,and tree species richness and diversity characteristics along DBH class,as well as changing trend of tree species diversity with increasing sampling area were analyzed. The results showed that the tree stem and species richness in the six plots both declined constantly along the DBH class gradient.For the communities of TMRFⅠ (altitude was 850~1 000 m),all indices had no clear trend with the gradient,while for the communities of TMRFⅡ (altitude 1 200~2 000 m),Shannon-Wiener and Simpson indices declined constantly with gradient,but Pielou's evenness index had the opposite trend.In smaller DBH classes (≥2 cm,≥5 cm and ≥10 cm),the tree species richness,diversity,and evenness of the communities of TMRFⅡ were obviously higher than those of the communities of TMRF Ⅰ,but there was no difference between the communities of TMRFⅠand TMRFⅡ in larger DBH classes (≥20.0 cm,≥30.0 cm and ≥50.0 cm).With sampling area increased,the tree species richness, Shannon-Wiener index,Simpson index and Pielou's evenness index of the six plots all had the trend to be smooth when the sampling area increased to 2 000 m 2.
    Population structure and community characteristics of Pseudotaxus chienii in Fengyangshan National Natural Reserve
    YANG Xu 1,YU Mingjian 1,DING Bingyang 2,XU Shuangxi 3,YE Lixin 3
    2005, 16(07):  1189-1194 . 
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    Pseudotaxus chienii,an endemic plant in China,is one of the second grade state protection wild plants,and distributes in Fengyangshan Natural Reserve as one of its concentrative dwelling places.A survey in the region was carried out on 10 communities,which were dominated by P.chienii.The analysis on its size structure,spatial distribution pattern and community characteristics showed that the populations of P.chienii could grow in the communities dominated by Rhododendron simiarum,Fokienia hodginsii-R.simiarum,and evergreen broad-leaved forests.In R.simiarum communities,the size structure, survival curve,and overwhelming community distribution pattern of P.chienii showed a sustaining development,while in communities dominated by F.hodginsiiR.simiarum,though the size structure was declining,the survival curve was Deevy-Ⅲ type.Plenty of plantlets were still existed,and the populations kept steady.Two types were considered to be the most suitable ones for P.chienii populations.The important value of P.chienii reached 5%~10%. In evergreen broad-leaved forests,the populations of P.chienii showed to be a declining type,and the survival curve was Deevy-Ⅱ type. The distribution pattern was random,indicating that P.chienii populations could not fit for survive in this kind of communities.Correlation analysis showed that P.chienii populations had a positive correlation with R.simiarum and F.hodginsii,but a negative correlation with Cyclobalanopsis stewardiana and Schima superba.P.chienii could associate to the habits with the community canopy density of about 0.6~0.8.From the results mentioned above, the populations of P.chienii could be able to sustain and develop,and the existing habitat in Fengyangshan should be protected effectively.The protection of P.chienii requires more basic work to establish efficient measures to protect its habitat.
    Root biomass and underground C and N storage of primitive Korean pine and broad-leaved climax forest in Changbai Mountains at its different succession stages
    YANG Liyun1,2,LUO Tianxiang3,WU Songtao2
    2005, 16(07):  1195-1199 . 
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    With more than 200 years old primitive Korean pine and broad?leaved climax forest and its two 20 and 80 years old secondary Populus davidiana and Betula platyphylla forests in Changbai Mountains as test objects,this paper studied their root biomass and underground C and N storage.The results showed that the root biomass of 20 years old,80 years old,and climax forests was 2.437,2.742 and 4.114 kg·m-2,respectively. with forest succession,the root C storage was 1.113,1.323 and 2.023 kg·m-2,soil C storage was 11.911,11.943 and 12.587 kg·m-2,and underground C storage was 13.024,13.266 and 14.610 kg·m-2,respectively,while the root N storage was 0.035,0.032 and 0.038 kg·m-2,soil N storage was 1.207,1.222 and 0.915 kg·m-2,and underground N storage was 1.243,1.254 and 0.955 kg·m-2, respectively, which indicated that along with forest succession,forest underground became a potential “carbon sink",whereas underground N storage did not change obviously.
    Temporal and spatial dynamics of reproductive modules of endangered plant Disanthus cercidifolius var.longipes natural populations
    XIAO Yian1,2,HE Ping1,HU Wenhai2,LI Xiaohong2
    2005, 16(07):  1200-1204 . 
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    Based on field observation data,this paper studied the flowering phenology and the temporal and spatial dynamics of the reproductive modules of endangered plant Disanthus cercidifolius var.longipes natural populations.The results showed that there were certain differences of the flowering phenology among the populations in different communities,e.g.,in pure forest,the average flowering duration of individuals was the longest (75 d),while the flowering synchrony was the lowest (0.717 d),but in bamboo forest,the flowering duration of individuals was the shortest (47 d),while its flowering synchrony was the highest.The numbers of reproductive branches and inflorescences were increased with increasing individual age,and reached the highest at the age of 30~35yr.At the elevation of 810 m,the numbers of individual reproductive branches and inflorescences reached the peak,and there were significant differences among the crown levels.The reproductive branch number of individuals and the inflorescences per reproductive branch were the highest in pure forest,being 411.39 and 7.857,respectively,while the inflorescences per reproductive branch in bamboo forest were notably lower than those in other communities.The abortive ratio of reproductive modules of young individuals was higher than that of the older ones in the flower?bud,flowering,and fruit phases.The abortion of reproductive modules had no correlation with their distributed elevation,but some correlations existed with their development time,distributed crown levels and communities.The major factor affecting the abortive ratio of individual reproduction modules was probably the illumination condition in the distributed communities.
    Characteristics of Robinia pseudoacacia water physiological ecology under different habitats in North Shaanxi gully areas of Loess Plateau
    SHAN Changjuan 1,2,LIANG Zongsuo 1,HAN Ruilian 1,HAO Wenfang 1
    2005, 16(07):  1205-1212 . 
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    With locust (Robinia pseudoacacia),the main tree species in afforestation,as test material,this paper studied the characteristics of its water physiological ecology and productivity under four habitats,i.e.,sunny,shady,semi-sunny and semi-shady hillsides,in the North Shaanxi gully areas of Loess Plateau.The mean water content in 0~500 cm soil layer was 8.87% (shady),8.06% (semi-shady),7.62% (semi-sunny),and 6.96% (sunny),respectively.There was a significant discrepancy between shady,semi?shady,semi-sunny and sunnyhillsides (α=0.01),and the difference between shady,semi-shady and semi-sunny,as well as between semi-sunny and sunny hillsides was also significant (α=0.05).Remarkable relationships were found between leaf RWC,locus WSD and soil water content (SWC).The leaf RWC and locust water potential under sunny hillside were lower,but those under shady hillside were higher.The daily mean transpiration was in order of shady (4.07 μg·cm-2·s-1) > semishady (3.89 μg·cm-2·s-1) > semi-sunny (3.05 μg·cm-2·s-1) > sunny (2.70 μg·cm-2·s-1) hillside.The remarkable difference of transpiration appeared at 11:00 and 13:00,and there existed a remarkable relationship between transpiration and light intensity,RH and soil water content.All of these resulted in a diversity of locust biomass under different habitats,the highest under shady hillside,and the lowest under sunny hillside,and the differences between different habitats were all significant.It could be concluded that soil water content was the main factor affecting locust growth.
    Relationship between species distribution and habitat effective temperature in subalpine meadow of Mt.Xiaowutai
    JIANG Yuan 1,HUANG Qiuru 2,HAN Jingsha 1,HUANG Xiaoxia 1,LIU Quanru 1
    2005, 16(07):  1213-1217 . 
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    By the methods of sugar-inversion,plant community field survey and laboratory analysis,this paper measured the effective temperature of habitats,relative coverage of species,and aboveground biomass in subalpine meadow of Mt.Xiaowutai,and analyzed the relationship between species distribution and habitat effective temperature in landscape scale.The results showed that among 97 vascular plant species registered,the distribution patterns of about 36% of total species were influenced by the effective temperature of the habitats,and the relative coverage of about 20% of them correlated significantly with the effective temperature.Eight species showed a negative correlation between their relative coverage and effective temperature, and eleven species had a positive correlation between their relative coverage or aboveground biomass and effective temperature. The eleven species with a positive correlation had certain drought resistance feature or a tendency distributing towards warmer habitats.Concerning the effectiveness of species feature applied in the analysis,relative coverage could be used to determine the relationship between species distribution and effective temperature efficiently,if the species frequency ranged from 90% to 20%.But,for the dominant species with their frequency over 90%, aboveground biomass seemed to be more suitable for the analysis.
    Estimation models for vegetation water content at both leaf and canopy levels
    SHEN Yan 1,2, NIU Zheng 2,YAN Chunyan 2
    2005, 16(07):  1218-1223 . 
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    Based on spectral indices method,this paper utilized the water content (Cw) and reflectance data of 67 fresh different type leaves from LOPEX'93 database to establish the statistical model between leaf Cw and spectral indices at leaf level through 47 samples,and to test the model with the other 20 samples.The results suggested that fuel moisture content (FMC) and equivalent water thickness (EWT) as Cw demonstrators were different in reflectance spectral curves.The difference between FMC and EWT was large when they were utilized to retrieve the leaf Cw.The correlation coefficient between EWT and each spectral index was higher than FMC,but the forecast precision of FMC was better than that of EWT.The 7 spectral indices could all retrieve the leaf FMC accurately,but only the Ratio975,II and SR were suitable to estimate the leaf EWT.Spectral indices linear model on the strength of optimal subset regressions had the highest precision to retrieve the leaf Cw.Ratio975 might be the universal spectral index to estimate the leaf Cw.At canopy level,the simulated canopy spectra under different leaf area index (LAI) and Cw were derived from the PROSPECT and SAILH coupling models.In order to eliminate background influence and to precisely retrieve the Cw,soil-adjusted water index (SAWI) was proposed at the first time to indicate the information of near-infrared and short-wave infrared canopy reflectance.The ratio of SAWI and other spectral indices could dramatically eliminate the soil background,and effectively retrieve the vegetation Cw at canopy level.Spectral index (Ratio975-0.96)/(SAWI+0.2) as improved Ratio975 could be used to compute the canopy Cw more precisely when LAI was ranging from 0.3 to 8.0 and Cw from 0.0001 to 0.07cm.
    Haloxylon ammodendron community patterns in different habitats along southeastern edge of Zhunger Basin
    WANG Chunling 1,GUO Quanshui 2,TAN Deyuan 3,SHI Zuomin 2,MA Chao 2
    2005, 16(07):  1224-1229 . 
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    Low-lying land,slow and gentle desert,and semi-mobile dune are the three different habitats of natural Haloxylon ammodendron community along the southeastern edge of Zhunger Basin in Xinjiang Uygur Autonomous Region.This paper studied the structural characters of H.ammodendron community from the aspects of species structure,species diversity, biomass, and distribution patterns of natural regeneration sapling.The results showed that the species of H.ammodendron community was the richest on low-lying land,the second on slow and gentle desert,and the least on semi-mobile dune.The number of plant species in the three different habitats was 16,15 and 12,respectively.The amount of H.ammodendron natural regeneration sapling was the largest (6 687 trees·hm-2) on semi-mobile dune,but its distribution was not even.Low-lying land had a slightly smaller amount (5 799 trees·hm-2) of H.ammodendron natural regeneration sapling than semimobile dune,but the distribution of the sapling was more even. The overall evaluation was that the natural regeneration of Haloxylon ammod endron community was the best on low?lying land.Its total biomass on low-lying land was 19.39 t·hm-2 ,while that on slow and gentle desert and semi-mobile dune was 9.32 and 6.69 t·hm-2,respectively.The distribution patterns of H.ammodendron natural regeneration sapling in different habitats were all aggregatice.The ground of low-lying land was fixed,with fairly good soil moisture and fertility,which was appropriate for the growth of H.ammodendron and the development of H.ammodendron community,while that of slow and gentle desert and semi-mobile dune was easier to suffer from wind erosion,with poor soil moisture and fertility and fairly serious habitat conditions.
    Phosphorus and sulphur bio-cycling in alpine tundra ecosystem of Changbai Mountains
    WEI Jing,WU Gang,WANG Huan,HAO Yingjie,SHANG Wenyan
    2005, 16(07):  1230-1234 . 
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    The study with compartment model on the phosphorus (P) and sulphur (S) bio-cycling in alpine tundra ecosystem of Changbai Mountains showed that the total storage of P and S was 16088.6 t and 26079.4 t,of which,46.14 t and 64.82 t was in vegetation pool,89.63 t and 53.16 t in litterfall pool,and 15952.8 t and 26 014.6 t in soil pool,respectively.The above?and below-ground vegetation pool stored 21.88 t and 44.21 t,and 24.28 t and 20.61 t of P and S,respectively, and the above-ground vegetation pool had 47.4% of P and 68.2% of S in the vegetation subsystem.The transferable P amount was 24.25 t·yr-1 through plant absorption and 31.59 t·yr-1 through litterfall return,while the transferable S amount was 31.18 t·yr-1,10.12 t·yr-1 and 21.06 t·yr-1 in the above-ground plant, below-ground root system,and litterfall return, respectively. The natural return ratio of S was 67.5%.
    Early responses of soil fauna in three typical forests of south subtropical China to simulated N deposition addition
    XU Guoliang 1,2,MO Jiangming 1,ZHOU Guoyi 1
    2005, 16(07):  1235-1240 . 
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    In this paper, simulated N deposition addition (0,50,100 and 150 kg·hm-2·yr-1) by spreading water or NH4NO3 was conducted to study the early responses of soil fauna in three typical native forests (monsoon evergreen broadleaf forest,pine forest,and broadleafpine mixed forest) of subtropical China.The results showed that in monsoon evergreen broadleaf forest,N deposition addition had an obviously negative effect on the three indexes for soil fauna,but in pine forest,the positive effect was significant (P<0.05),and the soil fauna community could reach the level in mixed forest,even that in monsoon evergreen broadleaf forest at sometime.The responses in mixed forest were not obvious.In monsoon evergreen broadleaf forest,the negative effects were significant (P<0.05) under medium N deposition,but not under low N deposition.In pine forest,the positive effect was significant (P<0.05) under high N deposition,especially for the number of soil fauna groups.The results obtained might imply the N saturation-response mechanisms of forest ecosystems in subtropical China,and the conclusions from this study were also consisted with some related researches.
    Ecological characteristics and modulate strategy of wintertime climate in self-controlled greenhouse
    LI Jun 1,2,YANG Qiuzhen 3,LUO Weihong 1
    2005, 16(07):  1241-1246 . 
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    Based on the five years observation data in self-controlled greenhouse at Donghai vegetable demonstration base in Shanghai,and adopting mathematical statistics methods,this paper analyzed the monthly variation characteristics of ambient illumination,temperature and CO2 concentration during wintertime,disclosed the persisting hours of favorable and unfavorable illumination grade under different weather conditions,appearing cases of different threshold air temperature,persisting hours and characteristics of CO2 shortfall,and variation characteristics of air relative humidity.The correlation equations between daytime average air temperature,CO2 concentration,relative humidity and illumination in greenhouse were set up,the main problems in self-controlled greenhouse during wintertime were pointed out,and some related modulate advises were put forward.In Shanghai area,the key points of obtaining high yields in greenhouse during wintertime should be to insure sufficient illumination,modulate air temperature at nights,raise forenoon air temperature in sunny days,and enlarge air temperature difference between daytime and night to increase net photosynthesis matters.
    Comprehensive management patterns of economic fruit forest in Dashan Village and their ecological and economic benefits
    ZHANG Tie,LI Hongkai,ZHU Yougang,YANG Xiaofei
    2005, 16(07):  1247-1251 . 
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    With the theories of economy and ecology,this paper analyzed the main management patterns of economic fruit forest in the Dashan Village,Huoqiu County,Anhui Province. The results showed that 9-year-old-mandarin-tea,5-year-old persimmon-potato-watermelon, 7-year-old pear-potato-soybean, and 7-year-old pear-balloonflower had obvious social,economic and ecological benefits.Their net economic benefits were 8 700.00,12 351.00,12 337.50 and 22 500.00 yuan·hm-2,respectively,higher than that of single crop planting.In these patterns,the crown density between rows could reach 0.3~0.4,and the light utilization rate increased by 20%~30%.
    Effects of rice-duck farming system on Oryza sativa growth and its yield
    YU Shengmiao 1,OUYANG Younan 1,ZHANG Qiuying 1,PENG Gang2,XU Dehai 1, JIN Qianyu 1
    2005, 16(07):  1252-1256 . 
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    The study showed that under rice?duck farming,the number of rice non-productive tiller reduced significantly,the ratio of its effective panicles increased by 8.08%,and its basal penetration light rate enhanced by 4.05%.At full-heading and maturing stages,the green leaf ratio under rice-duck farming was 6.01% and 10.65% higher than the control,and the leaf chlorophyll content was increased by 2.90% and 17.82%,respectively.Under rice-duck farming,the root vigour at full-heading stage and the photosynthesis capability of flag leaf at grain-filling stage were increased by 24.2% and 15.73%,which could accumulate more assimilative matter,and increase the harvest index and yield by 2.87% and 4.93%,respectively.
    Effects of genotype and environment on protein and starch quality of wheat grain
    ZHAO Chun 1,NING Tangyuan 1,JIAO Nianyuan 1,2,HAN Bin 1,LI Zengjia 1
    2005, 16(07):  1257-1260 . 
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    A field trial with 10 winter wheat varieties was conducted at 9 locations under different environmental conditions in Shandong Province to study the effects of wheat genotype and environment on the main qualitative characters of wheat grain.The results indicated that variety and environment had a marked influence on the main qualitative indexes of wheat grain,and the difference of environmental conditions was the main factor affecting the protein and gluten contents of the grain.The variation of farinogramme indexes was mainly due to the interaction between variety and environment. As for the starch content,peak viscosity,and breakdown of the grain, interactive effect was stronger than independent one,and the effect of variety was stronger than that of environment.
    Effects of osmotic stress on chlorophyll fluorescence parameters of wheat seedling
    ZHAO Liying,DENG Xiping,SHAN Lun
    2005, 16(07):  1261-1264 . 
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    By using chlorophyll fluorescence kinetics technology,this paper determined the chlorophyll fluorescence parameters Fv/Fm,ΦPSⅡ,qP,qNP,ETR of winter wheat seedling under simulated osmotic stress.The results showed that with the increase of osmotic stress, Fv/Fm and Fv/Fo had the trend of decrease-increase-decrease, indicating that photoinhibition did not happen at the first stage of osmotic stress,but the followed increase of Fv/Fm resulted in the photoinhibition and the decrease of ΦPSⅡand ETR.During the course of osmotic stress,qP and qNP decreased firstly and then increased,which was helpful to enhance the open ratio of PSⅡ reaction center,and made more photosynthetic energy use the photosynthetic electron transport to enhance the electron transport capacity.Meanwhile,the increase of non-photochemical quenching coefficient could be helpful to dissipate excess light energy,which protected the photosynthetic tissue,and mitigated the effect of environment on photosynthesis.All the results indicated that wheat seedling had its protection mechanism.Between the two test winter wheat varieties,Changwu 134 had a higher drought?resistance capacity than Shan 253.
    Photo-thermal characteristics of a non-photosensitive and extra-premature winter wheat variety
    Batur Bake 1,2,ZHENG Dawei 1,Herman van Keulen 2,Jan Verhagen 2, WU Funing 1,ZENG Xiaoguang 3
    2005, 16(07):  1265-1269 . 
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    In a sowing by stages test with winter wheat variety Jingdong 8 (JD8) as reference,this paper studied the photo?thermal characteristics of a non?photosensitive and extra-premature winter wheat variety Dongzao 5 (DZ5),and the effects of sowing stages on its growth and yield.The results showed that the harvest date of DZ5 was 4~5 days earlier than that of JD8,and its yield with standard sowing date increased by 43.4%.In addition,DZ5 had a shorter thermoperiod for ear differentiation,and didn't need strict vernalization process and photoperiod,which could be sown either before or after winter.
    Dynamics of soil active organic matter in Chinese fir plantations
    WANG Qingkui 1,2,WANG Silong 1,GAO Hong 1,YU Xiaojun 1
    2005, 16(07):  1270-1274 . 
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    Soil active organic matter is the main source of soil nutrients,and plays an important role in the formation and stabilization of soil aggregate.Chinese fir (Cunninghamia lanceolata) is the most important fast-growing timber tree species in southern China,but its continuous plantation has caused soil deterioration.The study on the active fractions of soil organic matter under the first and second generation plantations of Chinese fir and the native broad-leaved forest at Huitong Experimental Station of Forest Ecology, Chinese Academy of Sciences,in Hunan Province showed that their contents were higher under native broad-leaved forest than under Chinese fir plantations,and higher under the first than under the second generation plantation.The content of soil active organic carbon (SAOC),microbial biomass carbon (MBC),water-soluble organic carbon (WSOC) and water-soluble carbohydrate (WSC) was 18.79 g·kg-1,421.7 mg·kg-1,252.2mg·kg-1 and 136.3 mg·kg-1 under the first generation plantation of Chinese fir,and 22.31 g·kg-1,800.5 mg·kg-1,361.1 mg·kg-1 and 220.1 mg·kg-1 under the native broad-leaved forest,respectively.The corresponding values under the second generation plantation of Chinese fir were 73.6%,87.9%,66.3% and 53.2% of those under the first generation plantation of Chinese fir.The results also indicated that there existed some extent correlations among the active fractions of soil organic matter,and higher correlations between soil microbial biomass carbon and other active fractions of soil organic matter.
    Microbial diversity in continuously planted Chinese fir soil
    LI Yanmao 1,2,HU Jiangchun 1,ZHANG Jing 1,2,WANG Silong 1,WANG Shujin 1
    2005, 16(07):  1275-1278 . 
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    The study on the microbial diversity of 1st,2nd,3rd and 4th generation Chinese fir soil at Huitong Forest Experimental Station showed that with the increase of generation,the numbers of bacteria and actinomyces decreased markedly,while that of fungi increased evidently.It was found by PCR and DGGE that the bacterial diversity changed slightly and its genetic similarity among different generations reached 87%,but the fungal diversity reduced and its genetic similarity was only 45%.The numbers of pathogenic and deleterious fungi increased markedly with increasing Chinese fir generations.
    Effects of different de?farming and reafforestation patterns on changes of soil fertility quality in karst region of southwestern China
    LONG Jian 1,DENG Qiqiong 1,JIANG Xinrong 1,LIU Fang 2,3
    2005, 16(07):  1279-1284 . 
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    A ten-year fixed site harnessing was conducted in the severely eroded karst region of Ziyun County,Guizhou Province by adopting four different de?farming and reafforestation patterns,and the properties of soil chemistry,soil microbiology,and soil enzymology after harnessing were determined in 2003.The results showed that the total amount of soil microbes and the individuals of bacteria,fungi and actinomyces were increased obviously,the activities of soil hydrolytic and oxidoreductive enzymes and the soil respiration rate enhanced evidently,and the storage of soil nutrients as well as their supplying intensities promoted pronouncedly,demonstrating that the soil quality in all adopted patterns was improved in varying degrees.The values of soil integrated fertility index (IFI) had an increasing trend. Therefore,proper biological measures and essential supplementary engineering measures were effective in improving the soil fertility quality of severely degraded karst region.
    Spatial variability of slope land soil solute transport parameters
    ZHENG Jiyong 1,SHAO Mingan 1,2,ZHANG Xingchang 1,LI Shiqing 1
    2005, 16(07):  1285-1289 . 
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    In this paper,the transport parameters of chlorine in a slope land soil were determined in situ by fitting breakingthough curve,and the spatial variability of the parameters in a 41 m×5 m runoff plot was analyzed by using traditional and geo-statistics.The results showed that the average pore-water velocity increased gradually from the top to the bottom of the slope,and the diffusive-dispersive coefficient (D) had no remarkable variation within 20m away from the top but gradually increased with the distance beyond 20m.The dispersivity (α) had the same characteristics as D.The pore-water velocity (v) had a floating feature on the slope,while parameters D and α showed obvious spatial correlation characteristics,the range of the spatial correlation being 21m and 10m,respectively.
    Correlation between inhibition activity of endophytic fungus from Euphorbia pekinensis and its host
    DAI Chuanchao1,2,YU Boyang2,ZHAO Yuting1,YANG Qiyin1,JIANG Jihong3
    2005, 16(07):  1290-1294 . 
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    To develop endophytic fungi resources from medicinal plants,this paper studied the correlation between endophytic fungus Fusariium sp.E5 from Euphorbia pekinensis and its host through analyzing the inhibition activity of this pathogen.An endophytic strain S12 (Alternaria sp.) from Sapium sebiferum was used as contrast.The results showed that E5 had an inhibitory effect on the host,while S12 and E.pekinensis extract didn't have it.The inhibition activity of E5 could be stimulated by the extract of host leaf,and its inhibitory effect could only be found when it was cultured with enough oxygen.The inhibition activity was affected by pH,temperature,and ultra-violet.These characters of endophytic fungus E5 showed a good correlation with its host,and this correlation was mutualism.
    Effects of elevated CO2 concentration on rhizosphere soil microbes under Pinus koraiensis and Pinus sylvestriformis seedlings
    JIA Xia1,2,3,HAN Shijie1,ZHOU Yumei1,ZHANG Junhui1,ZOU Chunjing1
    2005, 16(07):  1295-1298 . 
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    The study showed that under Pinus sylvestriformis seedlings,the amount of rhizosphere soil bacteria,but not fungi and actinomyces,increased significantly (P≤0.001) with CO2 enrichment (700 and 500 μmol·mol-1),and the same (P≤ 0.001) was under Pinus koraiensis seedlings,with the exceptions of 700 μmol CO2·mol-1 in August and 500 μmol CO2·mol-1 in July,compared to the ambient chamber and the ambient in each month.No significant effect of elevated CO2 was found on the amount of rhizosphere soil fungi except in September (P≤0.01),and the response of actinomyces to elevated CO2 was also insignificant.
    N2O emission factor for agricultural soils
    LU Yanyu 1,HUANG Yao 1,2,ZHENG Xunhua 2
    2005, 16(07):  1299-1302 . 
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    Based on the direct measurements of annual N2O emission from 207 field experiments reported in literatures between 1982 and 2003,this paper established a database of annual N2O emission from agricultural fields.Correlation analysis indicated that the N2O emission from agricultural soils was significantly correlated with climatic factors temperature and precipitation,while no significant correlations were observed between N2O emission and edaphic parameters pH,organic carbon and nitrogen.According to the definition of N2O emission factor and its quantification by the Intergovernmental Panel on Climate Change,the N2O emission factor was modified by annual mean temperature and annual precipitation,respectively. The results suggested that the modification with precipitation might significantly reduce the estimated error of N2O emission by about 16%,while that with temperature did not reduce the error,in comparison with the default emission factor by the Intergovernmental Panel on Climate Change.
    Effects of organic manures on CO2 and CH4 fluxes of farmland
    DONG Yuhong 1,2,OUYANG Zhu 1
    2005, 16(07):  1303-1307 . 
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    This paper studied the effects of chicken manure,swine waste and cattle manure on the CO2 and CH4 fluxes of a farmland planted with summer maize.The results showed that the CO2 flux had the same trend under different organic manure application,which was influenced by soil temperature and soil water content.The flux was significantly related with air temperature,soil surface temperature and soil temperature (P<0.05).When soil temperature was not a limiting factor,soil water content was significantly related with soil CO2 flux.At most maize growth stages,soil was a sink of CH4.The variation of CH4 source-sink was influenced by environmental factors,but the correlation was not significant.The mean seasonal flux of CO2 was from 0.5124 to 0.8518 g·m-2·h-1,and that of CH4 was from-0.0068 to -0.0484 mg·m-2·h-1.Compared with CK2,maize planting and organic manure application enhanced CO2 emission.The application of organic manures inhibited the CH4 uptake by soil,and higher application rate had a higher inhibitory effect.
    Geostatistics analysis on spatial patterns of Myzus persicae and Erigonidium graminicola in plum orchard
    DING Chengcheng,ZOU Yunding,BI Shoudong,GAO Caiqiu,LIU Xiaolin,CAO Cuanwang,MENG Qinglei,LI Changgen
    2005, 16(07):  1308-1312 . 
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    Investigations on the spatial construction and distribution of Myzus persicae and Erigonidium graminicola in a plum orchard were conducted from March 2003 to November 2003.The results indicated that the semivariogram of Myzus persicae could be described by spherical model,except on June 27 and November 22,which should be described by lined model,and that of Erigonidium graminicola could be described by spherical model,except on May 21,May 31,October 19 and November 22,which should be described by lined model.It could be concluded that the amount and spatial distribution of Erigonidium graminicola was closely related to those of Myzus persicae.
    Effects of corn cultivar on Tetranychus truncatus Ehara (Acarina:Tetranychidae) population parameters
    PANG Baoping 1,LIU Jiaxiang 2,ZHOU Xiaorong 1,ZHANG Ruifeng 1
    2005, 16(07):  1313-1316 . 
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    The laboratory study at 28 ℃ showed that on four different corn cultivars,the durations of ovum,nymph and pre?oviposition,adult?longevity,fecundity,egg production per day,net reproductive rate (R0),finite rate of increase (λ),intrinsic rate of increase (rm),mean generation time (T),and the days needed to double population size (DDP) of Tetranychus truncatus were significantly different.The hatching rate on Zea mays cv.Zhongdan 2,Nongda 108,Chidan 202 and Badan 3 was 95.8%,94.0%,90.0% and 84.0%,and the survival rate on these cultivars was 90.5%,86.0%,84.0%,and 72.0%,respectively.All the survival curves were of Deevey Ⅰ.The net reproductive rate (R0) was the highest on Zhongdan 2,and the lowest on Badan 3.The mite displayed a decreasing preference in order of Zhongdan 2> Nongda 108> Chidan 202> Badan 3.
    Controlling effects of plant extracts and pesticides on Myzus persicae and Lipaphis erysimi populations
    ZHOU Qiong1,LIANG Guangwen2,ZENG Ling2,SHEN Shuping2,CEN Yijing 2
    2005, 16(07):  1317-1321 . 
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    This paper studied the controlling effects of Xanthium sibiricum and Syngonium podophyllum ethanol extracts,mobile oil emulsion and 0.3% azadirachtin EC on Myzus persicae and Lipaphis erysimi populations both in laboratory and in field.The results showed that in laboratory,X.sibiricum extract was the key deterrent to Myzus persicae,while sprayed it with S.podophyllum extract and with petroleum spray oil or 0.3% azadirachtin EC,the deterrent effect could be improved.As for pterigota Lipaphis erysimi,the extracts of the two plants were the main deterrents,and their interference effect was non?linear.In field,S.podophyllum extract had a stronger deterrent effect when sprayed independently.L.erysimi population could be successfully controlled by the mixtures of plant extracts and insecticides,with an efficiency of 95.7%.The best treatment against M.persicae population was X.sibiricum extract,with an efficiency of 87%,while S.podophyllum extract mixed with 0.3% azadirachtin EC,and X.sibiricum extract mixed with 0.3% azadirachtin EC had an efficiency of >80%.
    Roles of olfaction and vision in orientation behavior of adult Campylomma chinensis Schuh (Hemiptera:Miridae) toward Lantana plants (Verbanaceae)
    WU Weijian1,GAO Zezheng1,2,YU Jinyong1,LIANG Guangwen1
    2005, 16(07):  1322-1325 . 
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    Investigations were carried out on the orientation behavior of adult Campylomma chinensis Schuh (Hemiptera:Miridae) toward plant hosts Lantana camara,L.camara cv.‘Flava',and L.montevidensis (Spreng.) Briq.(Verbanaceae).Surveys on three Lantana plants showed that the distribution of C.chinensis in inflorescences was not related to floral color (partial correlation coefficient was 0.240,P=0.147,n=40),but to the number of Thrips hawiiensis Morgan (partial correlation coefficient was 0.512, P<0.0001,n=40) and the flowers per inflorescence (partial correlation coefficient was 0.451,P<0.0001,n=40).In a colour preference experiment,no adult C.chinensis attracted to six different colour plates in longan field.The testing results of fou-armed olfactometer indicated that adult C.chinensis had a significantly higher preference for L.camara.It was concluded that olfactory stimuli played an important role in searching for plant hosts of C.chinensis. Solid phase micro-extraction (SPME) and GC-MS were employed to analyze the volatiles compounds of Lantana,and seven same chemical constituents were detected from the volatiles of three Lantana plants inflorescence.
    Relationships of Aulacophora beetles feeding behavior with cucurbitacin types in host crops
    YANG Xiao1,KONG Chuihua1,2,LIANG Wenju2,ZHANG Maoxin1,HU Fei1
    2005, 16(07):  1326-1329 . 
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    Aulacophora fermoralis chinensis and Aulacophora cattigarensis are the two related Aulacophora beetles,but their host selectivity and feeding behavior are significantly different.A.fermoralis chinensis usually feeds upon Cucumis sativus and Cucurbita moschata,but never upon Luffa acutangula,Momordica charantia and Citrullas lanatus.Its feeding behavior on hosts is to snip a circular trench on their leaves,and then,to feed the leaf tissues isolated by the trench.On the contrary, A.cattigarensis only feeds L.acutangula,and its trenching behavior rarely occurs.This study showed that the host selectivity and feeding behavior of the two beetles were significantly correlated with the types of cucurbitacin biosynthesized by host melon crops.C.sativus and C.moschata might be induced to produce cucurbitacin I by A.fermoralis chinensis feeding,and this compound was responsible for feeding deterrent on A.fermoralis chinensis.Therefore,the feeding behavior of A.fermoralis chinensis was to block the translocation of cucurbitacin I to feeding sites.M.charantia and C.lanatus contained deterrent cucurbitacin D,and thus,both beetles never fed upon them,while L.acutangula contained stimulants cucurbitacin B and E,and made A.cattigarensis directly feed upon it without trenching.The results suggested that the taste responses of insects on specific allelochemicals from plants may play an important role in host selectivity and feeding behavior.
    Population dynamics of Bactrocera dorsalis (Diptera:Tephritidae) in Xishuang banna of Southern Yunnan
    YE Hui,LIU Jianhong
    2005, 16(07):  1330-1334 . 
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    In the study,an all year round monitoring through luretraps in 1997,2000 and 2003 was conducted on the population dynamics of oriental fruit fly,Bactrocera dorsalis (Diptera:Tephritidae) in Xishuangbanna of Southern Yunnan,and the factors in relation with its population fluctuation,including temperature,rainfall,and host species were analyzed.The fruit fly occurred year?round in Xishuangbanna,with a low population level from November to February,and increased steadily from March to July or August.An increasing peak appeared in July or August,depending on the rainfall amount in that year.Afterwards,the fly population declined markedly until to October. Temperature,rainfall,and host fruits were supposed to be the major factors affecting the population fluctuation.The monthly average temperature in Xishuangbanna was in the ranges suitable for the development and reproduction of the fly,but the monthly average minimum temperature from December to February appeared to be lower than the suitable temperature, which was suggested to be responsible for the low populations in the winter months.Rainfall was another essential factor affecting population fluctuation. The population was depressed when the monthly rainfall amount was lower than 50 mm,but increased when the amount ranged between 100 and 200 mm.Under conditions the monthly rainfall amount was higher than 250 mm,the fruit fly population was reduced markedly,which explained the decreasing population in July or August when the heavy rain occurred. Mango,orange,pear,longan,and peach were the main host species of the fly,among which,mango and longan were most preferred by the fly. Therefore, their planted area,fruiting period and productivity exerted essential effects on the fly population fluctuation,and regarded as another major factor affecting the fly population in this area.
    Hydrochemical characteristics of three kinds of wetland in Gongbiela Basin
    MAN Xiuling 1,2,CAI Tijiu 1
    2005, 16(07):  1335-1340 . 
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    The study on the hydrochemical characteristics of three representative kinds of wetland in Gongbiela Basin showed that in the water of test wetlands, HCO3- was the dominant anion,accounting for 81.91%~85.46% of total anions,and Ca2+ was the dominant cation,accounting for 56.80%~69.32% of total cations.The hydrochemical type belonged to that of bicarbonate calcium.In the three kinds of wetland,water pH ranged from 6.2 to 7.1,mineralization degree ranged from 112.56 to 461.23 mg·L-1,and hardness ranged from 14.31 to 148.53 mg·L-1.On the whole,the water quality of the wetlands met the grade 1 and grade 2 national environmental water quality standards,but the Fe and Mn contents exceeding the standards influenced the water resource quality of this area.The spatial and temporal changes of hydochemical characteristics of the wetlands and the trace element contents in the water were also discussed and analyzed.
    Zooplankton in north branch waters of Changjiang Estuary
    XU Zhaoli
    2005, 16(07):  1341-1345 . 
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    Based on the investigation data during the high-water (July,2003) and low-water (January,2004) periods,a causal analysis was made on the variation of zooplankton distribution in the north branch waters of the Changjiang Estuary.The results showed that in high-water period,the average of zooplankton biomass was 234.38 mg·m-3,being 141.35 mg·m-3 in flood tide and 327.40 mg·m-3 in ebb tide,while in low-water period,it was 188.81 mg·m-3,being 184.69 mg·m-3 in flood tide and 192.93 mg·m-3 in ebb tide.The biomass increased from the east to the west in flood tide,but a contrary trend was observed in ebb tide.The species number did not change obviously both in flood tide and in ebb tide.The value of diversity index (H') was higher in flood tide than in ebb tide.In high-water period,the biomass near the north shore was higher than that near the south shore,but it was contrary in the ebb tide.The difference between the waters of two shores was not obvious in low-water period as in high-water period,though the trend of biomass variation was similar.The variation of zooplankton distribution in the north branch waters of the Changjiang Estuary had a close relation with the seasonal changes of zooplankton biomass outside the Changjiang Estuary and the tide,but not significantly related with the Changjiang runoff water.Coriolis force accounted for the difference of zooplankton biomass in the waters of two shores via tide movement.
    Recruitment dynamics of bloom?forming cyanobacteria in Meiliang Bay of Taihu Lake
    ZHANG Xiaofeng1,2,KONG Fanxiang1,CAO Huansheng1,3,TAN Jiankang2,TAO Yi 2, WANG Meilin 2
    2005, 16(07):  1346-1350 . 
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    A collection trap was installed on the sediments in Meiliang Bay of Taihu Lake during the period from March to June to investigate the recruitment of phytoplankton,and cyanobacteria in particular.The algal abundance in the trap was monitored,and compared with that in water column and surface sediments.The results showed that the algal recruitment was related to the temperature,irradiance,DO content,and oxidation?reduction potential (ORP) in surface sediment.After over wintering on the sediments,the colonies of cyanobacteria experienced a prior developmental process before re?invasion of the water column.During the investigation period,the recruitment rates of chlorophyll a and b and PC were 59.84%,76.83% and 466.98%,and the recruitment amounts accounted for 7.18%,3.71% and 9.33% of their maximum pelagic counterparts in water column,respectively.These results showed that shallow lake was the important seed bank to the pelagic populations,and water bloom was formed as the result of the recruitment and biomass accumulation of cyanobacteria.
    Accumulation of non?point source pollutants in ditch wetland and their uptake and purification by plants
    JIANG Cuiling,FAN Xiaoqiu,ZHANG Yibing
    2005, 16(07):  1351-1354 . 
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    The study on the vertical and horizontal distribution of organic matters and total nitrogen (TN) in the sediment of ditch wetland naturally grown with reed (Phragmites communis) and wild rice (Zizania latifolia) showed that the sediment below 40 cm depth had a significant effectiveness in retaining and accumulating organic matters and TN,but in its surface layer,this effectiveness varied largely with seasons,and the maximum was more than twofold of the minimum.TN was highly correlated with organic matters,the correlation coefficient being 0.9876 in reed wetland and 0.9335 in wild rice wetland,and in water phase,it was positively related to NH4+-N and NO3-N,indicating that the main composition of TN was organic N,and the mineralization of organic N was the sources of inorganic N.The harvest of reed in each autumn could take away 818 kg·hm-2 of N and 103.6 kg·hm-2 of P,and that of wild rice could take away 131 kg·hm-2 of N and 28.9 kg·hm-2 of P.Zizania caduciflora had a high assimilation ability of nutrients.Its cultivation in ditch wetland to replace wild helophytes would be a good approach to attain higher absorbing ability of N and P,and to resolve the secondary pollution problem of emerged plants,because farmers could harvest it voluntarily.
    Impacts of petroleum?containing wastewater irrigation on microbial population and enzyme activities in paddy soil of Shenfu irrigation area
    LI Hui 1,2,CHEN Guanxiong 1,3,YANG Tao 1,4,ZHANG Chenggang 1
    2005, 16(07):  1355-1359 . 
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    The study showed that the upper reaches of main petroleum-containing wastewater irrigation channels had the highest accumulation and distribution of total petroleum hydrocarbon (TPH) (5 213.37 mg·kg-1 dry soil),and the CFU of soil bacteria and fungi was increased with increasing soil TPH concentration,the correlation coefficient being 0.928 (P<0.001) and 0.772 (P<0.05),respectively.The activities of soil dehydrogenase,catalase and polyphenoloxidase had a significantly positive correlation with soil TPH concentration,their correlation coefficient being 0.974 (P<0.001),0.957 (P<0.001) and 0.886 (P<0.001),respectively,while soil urease activity showed a significantly negative correlation (P=0.002),which could be used as the most sensitive indicator of petroleum contamination.The substrate-induced respiration (SIR) of polluted soil was significantly correlated with soil TPH concentration (P<0.001),dehydrogenase activity (P<0.001),and heterotrophic bacterial CFU (P=0.006).
    Effects of environmental factors on Cd biotoxicity and phytochelatins production in Triticum aestivum
    SUN Qin,YUAN Xinfang,WANG Xiaorong
    2005, 16(07):  1360-1365 . 
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    In this paper,a solution culture experiment was conducted to study the effects of environmental factors on Cd biotoxicity and phytochelatins (PCs) production in wheat.The results showed that Cd stress had significant inhibitory effects on wheat growth and PCs overproduction.The Cd biotoxicity and Cd uptake by wheat were affected in varying degrees by soil pH,Ca and S,and the levels of PCs production in root were consistent with the changes of Cd biotoxicity.Furthermore,the Cd biotoxicity was decreased with increasing P supply,coinciding with the decrease of PCs level in root.Mg had no obvious effect on both Cd biotoxicity and PCs level in root.The present results further confirmed that the induced PCs production level by Cd was related to Cd biotoxicity in plant,suggesting that PCs could be a promising biomarker for estimating Cd phytotoxicity.
    Effects of urbanization on landscape pattern of Beijing
    SUN Yajie,WANG Qingxu,LU Zhaohua
    2005, 16(07):  1366-1369 . 
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    Landscape pattern of Beijing urban areas within the six-ringed road was classified based on 1997 and 2002 remote sensing data. The indices from landscape level were computed using Fragstats3.3 to study the landscape pattern change of Beijing urban areas from 1997 to 2002.The results showed that the number of patches increased by 106.6%,the mean patch area decreased by 51.6%,the splitting index increased by 94.3%, and the landscape diversity index increased by 17.8%.The landscape pattern tended to be fragmentized and diversified in those five years. The reason of this change was the increased need for construction land due to the growing population and the improvement of living standard. Landscape pattern change of Beijing might influence the changes of substance flow and energy flow. It also provided some fundamental landscape scale data and some suggestions for development and planning of Beijing city.
    Ecological footprint and available ecological capacity in Chongqing region
    SUN Fan,MONG Linbing
    2005, 16(07):  1370-1374 . 
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    Based on the statistical data of Chongqing,the ecological footprint of Chongqing was calculated in this paper.The results showed that the per capita ecological footprint was 1.653566 hm2,per capita ecological capacity was 0.280393 hm2,and ecological surplus of deficit was 1.373173 hm2.The per capita ecological footprint was 0.5335 hm2(47.64%) higher but the per capita ecological capacity was 0.5196 hm2 (64.95%) lower,and the ecological surplus of deficit was about 3.43 times of the average national level.These results showed that the ecological footprint of Chongqing was beyond the available ecological capacity,and its social and economic development was not sustainable.The strategies on reducing ecological deficit in this region,such as reducing ecosystem population,increasing public finance income,and controlling environmental pollution,were also put forward.
    Animal immunocompetence and its effect on population regulation and life history tradeoff
    ZHANG Zhiqiang 1,2,WANG Dehua 1
    2005, 16(07):  1375-1379 . 
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    Immunocompetence is a common conception in biomedical and animal sciences, and refers to the ability of organisms against diseases.In recent years,a new field,ecological immunology,has been received much attention, which deals with the variation of immunocompetence in wildlife by immune methods.This paper introduced the conception of immunocompetence,the factors affecting its performance,and its roles in regulating animal population dynamics.Some hypotheses on population regulation in small mammals,such as immunocompetence handicap hypothesis,immunocompetence selection hypothesis and winter immune enhancement hypothesis were summarized. The relationships among energy metabolism,endocrine controlling mechanism and immune system were introduced,and the recent progress on immunocompetence and life history tradeoff was analyzed.The tradeoff between survival and immunocompetence,as well as between reproduction and immunocompetence were discussed,and some developing perspectives and new problems in ecological immunology were proposed.
    Bacterial flora composition and its dynamics in tidalflat Sinonovacula constricta aquaculture area
    JIN Shan 1,XUE Chaobo 1,2,WANG Guoliang 1,LU Tongxia 1,WANG Yinong1, CHEN Yiner 1
    2005, 16(07):  1380-1382 . 
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    In this study,the bacteria from the mud in tidal?flat Sinonovacula constricta aquaculture area were isolated each month from March to December, 2002,and the temporal and spatial distribution of heterotrophic bacteria, ammonifying bacteria,denitrifying bacteria,and sulphate reducing bacteria were analyzed.The results showed that all the 515 isolated bacteria mainly belonged to 1 family and 13 genera.The bacterial flora in different layers of the mud was almost consistent,while the composition was different.The predominant genera were Clostridium,Bacillus, Corynebacterium, Photobacterium, and some Enterobacteriaceae.The number of heterotrophic bacteria in the surface layer and the bottom fluctuated in 7.6×103 cfu·g-1~2.0×105 and 1.6×10 3~1.0×105 cfu·g-1,ammonifying bacteria fluctuated in 1.5×10 6~9.0×107 and 9.0×10 5~1.0×10 7 cfu·g-1,denitrifying bacteria fluctuated in 9.0×10 3~4.0×10 6 and 1.9×10 4~2.0×10 6 and 5.0×10 2~1.9×10 6 cfu·g-1,and sulphate reducing bacteria fluctuated in 5.0×10 4~5.0×10 6 ~4.0×10 6 cfu·g-1,respectively.The detection rates of ammonifying bacteria,denitrifying bacteria and sulphate reducing bacteria in the mud were all 100%,and these bacteria increased significantly in the second half of the year,indicating that the environment of the Sinonovacula constricta aquaculture area was deteriorated due to the accumulation of NH3, nitrite and H2S,and it is important to regulate the breed capacity and redistribute the breeding environment.
    Tree species diversity of tropical montane rain forest in Xishuangbanna,Yunnan
    LI Zongshan, TANG Jianwei, ZHENG Zheng, ZHU Shengzhong, DUAN Wenyong, SONG Junping, GUO Xianming, ZENG Rong
    2005, 16(7):  1183-1188. 
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    Tropical montane rain forest (TMR),one of the main forest vegetation types in Xishuangbanna of Yunnan Province,occurs horizontally in the north (TMRFⅠ) and vertically in the south (TMRFⅡ).In order to understand its tree species diversity in different zones,six fixed plots (50 m×50m) at different sites in Xishuangbanna were established,two (plots 1 and 2) for TMRF I,and four (plots 3,4,5 and 6) for TMRF II.Grid method (10 m×10 m) was used to record all the individuals with DBH greater than 2.0 cm in each plot,and tree species richness and diversity characteristics along DBH class,as well as changing trend of tree species diversity with increasing sampling area were analyzed.The results showed that the tree stem and species richness in the six plots both declined constantly along the DBH class gradient.For the communities of TMRFⅠ (altitude was 850~(1000) m,all indices had no clear trend with the gradient,while for the communities of TMRFⅡ (altitude 1 200~2 000 m),Shannon-Wiener and Simpson indices declined constantly with gradient,but Pielou's evenness index had the opposite trend.In smaller DBH classes (≥2 cm,≥5 cm and ≥10 cm),the tree species richness,diversity,and evenness of the communities of TMRFⅡ were obviously higher than those of the communities of TMRF Ⅰ,but there was no difference between the communities of TMRFⅠand TMRFⅡ in larger DBH classes (≥20.0 cm,≥30.0 cm and ≥50.0 cm).With sampling area increased,the tree species richness,Shannon-Wiener index,Simpson index and Pielou's evenness index of the six plots all had the trend to be smooth when the sampling area increased to 2 000 m2.
    Population structure and community characteristics of Pseudotaxus chienii in Fengyangshan National Natural Reserve
    YANG Xu, YU Mingjian, DING Bingyang, XU Shuangxi, YE Lixin
    2005, 16(7):  1189-1194. 
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    Pseudotaxus chienii,an endemic plant in China,is one of the second grade state protection wild plants,and distributes in Fengyangshan Natural Reserve as one of its concentrative dwelling places.A survey in the region was carried out on 10 communities,which were dominated by P.chienii.The analysis on its size structure,spatial distribution pattern and community characteristics showed that the populations of P.chienii could grow in the communities dominated by Rhododendron simiarum,Fokienia hodginsii-R.simiarum,and evergreen broad-leaved forests.In R.simiarum communities,the size structure,survival curve,and overwhelming community distribution pattern of P.chienii showed a sustaining development,while in communities dominated by F.hodginsii-R.simiarum,though the size structure was declining,the survival curve was Deevy-Ⅲ type.Plenty of plantlets were still existed,and the populations kept steady.Two types were considered to be the most suitable ones for P.chienii populations.The important value of P.chienii reached 5%~10%. In evergreen broad-leaved forests,the populations of P.chienii showed to be a declining type,and the survival curve was Deevy-Ⅱ type.The distribution pattern was random,indicating that P.chienii populations could not fit for survive in this kind of communities.Correlation analysis showed that P.chienii populations had a positive correlation with R.simiarum and F.hodginsii,but a negative correlation with Cyclobalanopsis stewardiana and Schima superba.P.chienii could associate to the habits with the community canopy density of about 0.6~0.8.From the results mentioned above,the populations of P.chienii could be able to sustain and develop,and the existing habitat in Fengyangshan should be protected effectively.The protection of P.chienii requires more basic work to establish efficient measures to protect its habitat.
    Root biomass and underground C and N storage of primitive Korean pine and broad-leaved climax forest in Changbai Mountains at its different succession stages
    YANG Liyun, LUO Tianxiang, WU Songtao
    2005, 16(7):  1195-1199. 
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    With more than 200 years old primitive Korean pine and broad-leaved climax forest and its two 20 and 80 years old secondary Populus davidiana and Betula platyphylla forests in Changbai Mountains as test objects,this paper studied their root biomass and underground C and N storage.The results showed that with forest succession,the root biomass of 20 years old,80 years old,and climax forests was 2.437,2.742 and 4.114 kg·m-2,respectively.The root C storage was 1.113,1.323 and 2.023 kg·m-2,soil C storage was 11.911,11.943 and 12.587 kg·m-2,and underground C storage was 13.024,13.266 and 14.610 kg·m-2,respectively,while the root N storage was 0.035,0.032 and 0.038 kg·m-2,soil N storage was 1.207,1.222 and 0.915 kg·m-2,and underground N storage was 1.243,1.254 and 0.955 kg·m-2,respectively,which indicated that along with forest succession,forest underground became a potential “carbon sink",whereas underground N storage did not change obviously.
    Temporal and spatial dynamics of reproductive modules of endangered plant Disanthus cercidifolius varlongipes natural populations
    XIAO Yian, HE Ping, HU Wenhai, LI Xiaohong
    2005, 16(7):  1200-1204. 
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    Based on field observation data,this paper studied the flowering phenology and the temporal and spatial dynamics of the reproductive modules of endangered plant Disanthus cercidifolius var.longipes natural populations.The results showed that there were certain differences of the flowering phenology among the populations in different communities,e.g.,in pure forest,the average flowering duration of individuals was the longest (75 d),while the flowering synchrony was the lowest (0.717 d),but in bamboo forest,the flowering duration of individuals was the shortest (47 d),while its flowering synchrony was the highest.The numbers of reproductive branches and inflorescences were increased with increasing individual age,and reached the highest at the age of 30~35 yr.At the elevation of 810 m,the numbers of individual reproductive branches and inflorescences reached the peak,and there were significant differences among the crown levels.The reproductive branch number of individuals and the inflorescences per reproductive branch were the highest in pure forest,being 411.39 and 7.857,respectively,while the inflorescences per reproductive branch in bamboo forest were notably lower than those in other communities.The abortive ratio of reproductive modules of young individuals was higher than that of the older ones in the flower-bud,flowering,and fruit phases.The abortion of reproductive modules had no correlation with their distributed elevation,but some correlations existed with their development time,distributed crown levels and communities.The major factor affecting the abortive ratio of individual reproduction modules was probably the illumination condition in the distributed communities.
    Characteristics of Robinia pseudoacacia water physiological ecology under different habitats in North Shaanxi gully areas of Loess Plateau
    SHAN Changjuan, LIANG Zongsuo, HAN Ruilian, HAO Wenfang
    2005, 16(7):  1205-1212. 
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    With locust (Robinia pseudoacacia),the main tree species in afforestation,as test material,this paper studied the characteristics of its water physiological ecology and productivity under four habitats,i.e.,sunny,shady,semi-sunny and semi-shady hillsides,in the North Shaanxi gully areas of Loess Plateau.The mean water content in 0~500 cm soil layer was 8.87% (shady),8.06% (semi-shady),7.62% (semi-sunny),and 6.96% (sunny),respectively.There was a significant discrepancy between shady,semi-shady,semi-sunny and sunnyhillsides (α=0.01),and the difference between shady,semi-shady and semi-sunny,as well as between semi-sunny and sunny hillsides was also significant (α=0.05).Remarkable relationships were found between leaf RWC,locus WSD and soil water content (SWC).The leaf RWC and locust water potential under sunny hillside were lower,but those under shady hillside were higher.The daily mean transpiration was in order of shady (4.07 μg·cm-2·s-1) > semi-shady (3.89 μg·cm-2·s-1) > semi-sunny (3.05 μg·cm-2·s-1) > sunny (2.70 μg·cm-2·s-1) hillside.The remarkable difference of transpiration appeared at 11:00 and 13:00,and there existed a remarkable relationship between transpiration and light intensity,RH and soil water content.All of these resulted in a diversity of locust biomass under different habitats,the highest under shady hillside,and the lowest under sunny hillside,and the differences between different habitats were all significant.It could be concluded that soil water content was the main factor affecting locust growth.
    Relationship between species distribution and habitat effective temperature in subalpine meadow of Mt.Xiaowutai
    JIANG Yuan, HUANG Qiuru, HAN Jingsha, HUANG Xiaoxia, LIU Quanru
    2005, 16(7):  1213-1217. 
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    By the methods of sugar-inversion,plant community field survey and laboratory analysis,this paper measured the effective temperature of habitats,relative coverage of species,and aboveground biomass in subalpine meadow of Mt.Xiaowutai,and analyzed the relationship between species distribution and habitat effective temperature in landscape scale.The results showed that among 97 vascular plant species registered,the distribution patterns of about 36% of total species were influenced by the effective temperature of the habitats,and the relative coverage of about 20% of them correlated significantly with the effective temperature.Eight species showed a negative correlation between their relative coverage and effective temperature,and eleven species had a positive correlation between their relative coverage or aboveground biomass and effective temperature.The eleven species with a positive correlation had certain drought resistance feature or a tendency distributing towards warmer habitats.Concerning the effectiveness of species feature applied in the analysis,relative coverage could be used to determine the relationship between species distribution and effective temperature efficiently,if the species frequency ranged from 90% to 20%.But,for the dominant species with their frequency over 90%,aboveground biomass seemed to be more suitable for the analysis.
    Estimation models for vegetation water content at both leaf and canopy levels
    SHEN Yan, NIU Zheng, YAN Chunyan
    2005, 16(7):  1218-1223. 
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    Based on spectral indices method,this paper utilized the water content (Cw) and reflectance data of 67 fresh different type leaves from LOPEX'93 database to establish the statistical model between leaf Cw and spectral indices at leaf level through 47 samples,and to test the model with the other 20 samples.The results suggested that fuel moisture content (FMC) and equivalent water thickness (EWT) as Cw demonstrators were different in reflectance spectral curves.The difference between FMC and EWT was large when they were utilized to retrieve the leaf Cw.The correlation coefficient between EWT and each spectral index was higher than FMC,but the forecast precision of FMC was better than that of EWT.The 7 spectral indices could all retrieve the leaf FMC accurately,but only the Ratio975,II and SR were suitable to estimate the leaf EWT.Spectral indices linear model on the strength of optimal subset regressions had the highest precision to retrieve the leaf Cw.Ratio975 might be the universal spectral index to estimate the leaf Cw.At canopy level,the simulated canopy spectra under different leaf area index (LAI) and Cw were derived from the PROSPECT and SAILH coupling models.In order to eliminate background influence and to precisely retrieve the Cw,soil-adjusted water index (SAWI) was proposed at the first time to indicate the information of near-infrared and short-wave infrared canopy reflectance.The ratio of SAWI and other spectral indices could dramatically eliminate the soil background,and effectively retrieve the vegetation Cw at canopy level.Spectral index (Ratio975-0.96)/(SAWI+0.2) as improved Ratio975 could be used to compute the canopy Cw more precisely when LAI was ranging from 0.3 to 8.0 and Cw from 0.0001 to 0.07cm.
    Haloxylon ammodendron community patterns in different habitats along southeastern edge of Zhunger Basin
    WANG Chunling, GUO Quanshui, TAN Deyuan, SHI Zuomin, MA Chao
    2005, 16(7):  1224-1229. 
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    Low-lying land,slow and gentle desert,and semi-mobile dune are the three different habitats of natural Haloxylon ammodendron community along the southeastern edge of Zhunger Basin in Xinjiang Uygur Autonomous Region.This paper studied the structural characters of H.ammodendron community from the aspects of species structure,species diversity,biomass,and distribution patterns of natural regeneration sapling.The results showed that the species of H.ammodendron community was the richest on low-lying land,the second on slow and gentle desert,and the least on semi-mobile dune.The number of plant species in the three different habitats was 16,15 and 12,respectively.The amount of H.ammodendron natural regeneration sapling was the largest (6 687 trees穐m-2) on semi-mobile dune,but its distribution was not even.Low-lying land had a slightly smaller amount (5 799 trees穐m-2) of H.ammodendron natural regeneration sapling than semi-mobile dune,but the distribution of the sapling was more even.The overall evaluation was that the natural regeneration of H. ammodendron community was the best on low-lying land.Its total biomass on low-lying land was 19.39 t穐m-2,while that on slow and gentle desert and semi-mobile dune was 9.32 and 6.69 t穐m-2,respectively.The distribution patterns of H.ammodendron natural regeneration sapling in different habitats were all aggregatice.The ground of low-lying land was fixed,with fairly good soil moisture and fertility,which was appropriate for the growth of H.ammodendron and the development of H.ammodendron community,while that of slow and gentle desert and semi-mobile dune was easier to suffer from wind erosion,with poor soil moisture and fertility and fairly serious habitat conditions.
    Phosphorus and sulphur bio-cycling in alpine tundra ecosystem of Changbai Mountains
    WEI Jing, WU Gang, WANG Huan, HAO Yingjie, SHANG Wenyan
    2005, 16(7):  1230-1234. 
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    The study with compartment model on the phosphorus (P) and sulphur (S) bio-cycling in alpine tundra ecosystem of Changbai Mountains showed that the total storage of P and S was 16 088.6 t and 26 079.4 t,of which,46.14 t and 64.82 t was in vegetation pool,89.63 t and 53.16 t in litterfall pool,and 15952.8 t and 26 014.6 t in soil pool,respectively.The above- and below-ground vegetation pool stored 21.88 t and 44.21 t,and 24.28 t and 20.61 t of P and S,respectively,and the above-ground vegetation pool had 47.4% of P and 68.2% of S in the vegetation subsystem.The transferable P amount was 24.25 t穣r-1 through plant absorption and 31.59 t穣r-1 through litterfall return,while the transferable S amount was 31.18 t穣r-1,10.12 t穣r-1 and 21.06 t穣r-1 in the aboveground plant,belowground root system,and litterfall return,respectively.The natural return ratio of S was 67.5%.
    Early responses of soil fauna in three typical forests of south subtropical China to simulated N deposition addition
    XU Guoliang, MO Jiangming, ZHOU Guoyi
    2005, 16(7):  1235-1240. 
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    In this paper,simulated N deposition addition (0,50,100 and 150 kg穐m-2穣r-1) by spreading water or NH4NO3 was conducted to study the early responses of soil fauna in three typical native forests (monsoon evergreen broadleaf forest,pine forest,and broadleaf-pine mixed forest) of subtropical China.The results showed that in monsoon evergreen broadleaf forest,N deposition addition had an obviously negative effect on the three indexes for soil fauna,but in pine forest,the positive effect was significant (P<0.05),and the soil fauna community could reach the level in mixed forest,even that in monsoon evergreen broadleaf forest at sometime.The responses in mixed forest were not obvious.In monsoon evergreen broadleaf forest,the negative effects were significant (P<0.05) under medium N deposition,but not under low N deposition.In pine forest,the positive effect was significant (P<0.05) under high N deposition,especially for the number of soil fauna groups.The results obtained might imply the N saturation-response mechanisms of forest ecosystems in subtropical China,and the conclusions from this study were also consisted with some related researches.
    Ecological characteristics and modulate strategy of wintertime climate in self-controlled greenhouse
    LI Jun, YANG Qiuzhen, LUO Weihong
    2005, 16(7):  1241-1246. 
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    Based on the five years observation data in self-controlled greenhouse at Donghai vegetable demonstration base in Shanghai,and adopting mathematical statistics methods,this paper analyzed the monthly variation characteristics of ambient illumination,temperature and CO2 concentration during wintertime,disclosed the persisting hours of favorable and unfavorable illumination grade under different weather conditions,appearing cases of different threshold air temperature,persisting hours and characteristics of CO2 shortfall,and variation characteristics of air relative humidity.The correlation equations between daytime average air temperature,CO2 concentration,relative humidity and illumination in greenhouse were set up,the main problems in self-controlled greenhouse during wintertime were pointed out,and some related modulate advises were put forward.In Shanghai area,the key points of obtaining high yields in greenhouse during wintertime should be to insure sufficient illumination,modulate air temperature at nights,raise forenoon air temperature in sunny days,and enlarge air temperature difference between daytime and night to increase net photosynthesis matters.
    Comprehensive management patterns of economic fruit forest in Dashan Village and their ecological and economic benefits
    ZHANG Tie, LI Hongkai, ZHU Yougang, YANG Xiaofei
    2005, 16(7):  1247-1251. 
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    With the theories of economy and ecology,this paper analyzed the main management patterns of economic fruit forest in the Dashan Village,Huoqiu County,Anhui Province.The results showed that 9-year-old mandarin-tea,5-year-old persimmon-potato-watermelon,7-year-old pear-potato-soybean,and 7-year-old pear-balloonflower had obvious social,economic and ecological benefits.Their net economic benefits were (8 700.00),(12 351.00),(12 337.50) and (22 500.00) yuan·hm-2,respectively,higher than that of single crop planting.In these patterns,the crown density between rows could reach 0.3~0.4,and the light utilization rate increased by 20%~30%.
    Effects of rice-duck farming system on Oryza sativa growth and its yield
    YU Shengmiao, OUYANG Younan, ZHANG Qiuying, PENG Gang, XU Dehai, JIN Qianyu
    2005, 16(7):  1252-1256. 
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    The study showed that under rice-duck farming,the number of rice non-productive tiller reduced significantly,the ratio of its effective panicles increased by 8.08%,and its basal penetration light rate enhanced by 4.05%.At full-heading and maturing stages,the green leaf ratio under rice-duck farming was 6.01% and 10.65% higher than the control,and the leaf chlorophyll content was increased by 2.90% and 17.82%,respectively.Under rice-duck farming,the root vigour at full-heading stage and the photosynthesis capability of flag leaf at grain-filling stage were increased by 24.2% and 15.73%,which could accumulate more assimilative matter,and increase the harvest index and yield by 2.87% and 4.93%,respectively.
    Effects of genotype and environment on protein and starch quality of wheat grain
    ZHAO Chun, NING Tangyuan, JIAO Nianyuan, HAN Bin, LI Zengjia
    2005, 16(7):  1257-1260. 
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    A field trial with 10 winter wheat varieties was conducted at 9 locations under different environmental conditions in Shandong Province to study the effects of wheat genotype and environment on the main qualitative characters of wheat grain.The results indicated that variety and environment had a marked influence on the main qualitative indexes of wheat grain,and the difference of environmental conditions was the main factor affecting the protein and gluten contents of the grain.The variation of farinogramme indexes was mainly due to the interaction between variety and environment.As for the starch content,peak viscosity,and breakdown of the grain,interactive effect was stronger than independent one,and the effect of variety was stronger than that of environment.
    Effects of osmotic stress on chlorophyll fluorescence parameters of wheat seedling
    ZHAO Liying, DENG Xiping, SHAN Lun
    2005, 16(7):  1261-1264. 
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    By using chlorophyll fluorescence kinetics technology,this paper determined the chlorophyll fluorescence parameters Fv/Fm,ΦPSⅡ,qP,qNP,ETR of winter wheat seedling under simulated osmotic stress.The results showed that with the increase of osmotic stress,Fv/Fm and Fv/Fo had the trend of decrease-increase-decrease,indicating that photoinhibition did not happen at the first stage of osmotic stress,but the followed increase of Fv/Fm resulted in the photoinhibition and the decrease of ΦPSⅡand ETR.During the course of osmotic stress,qP and qNP decreased firstly and then increased,which was helpful to enhance the open ratio of PSⅡ reaction center,and made more photosynthetic energy use the photosynthetic electron transport to enhance the electron transport capacity.Meanwhile,the increase of non-photochemical quenching coefficient could be helpful to dissipate excess light energy,which protected the photosynthetic tissue,and mitigated the effect of environment on photosynthesis.All the results indicated that wheat seedling had its protection mechanism.Between the two test winter wheat varieties,Changwu 134 had a higher drought-resistance capacity than Shan 253.
    Photo-thermal characteristics of a non-photosensitive and extra-premature winter wheat variety
    Batur Bake, ZHENG Dawei, Herman van Keulen, Jan Verhagen, WU Funing, ZENG Xiaoguang
    2005, 16(7):  1265-1269. 
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    In a sowing by stages test with winter wheat variety Jingdong 8 (JD8) as reference,this paper studied the photo-thermal characteristics of a non-photosensitive and extra- premature winter wheat variety Dongzao 5 (DZ5),and the effects of sowing stages on its growth and yield.The results showed that the harvest date of DZ5 was 4~5 days earlier than that of JD8,and its yield with standard sowing date increased by 43.4%.In addition,DZ5 had a shorter thermoperiod for ear differentiation,and didn't need strict vernalization process and photoperiod,which could be sown either before or after winter.
    Dynamics of soil active organic matter in Chinese fir plantations
    WANG Qingkui, WANG Silong, GAO Hong, YU Xiaojun
    2005, 16(7):  1270-1274. 
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    Soil active organic matter is the main source of soil nutrients,and plays an important role in the formation and stabilization of soil aggregate.Chinese fir (Cunninghamia lanceolata) is the most important fast-growing timber tree species in southern China,but its continuous plantation has caused soil deterioration.The study on the active fractions of soil organic matter under the first and second generation plantations of Chinese fir and the native broad-leaved forest at Huitong Experimental Station of Forest Ecology,Chinese Academy of Sciences,in Hunan Province showed that their contents were higher under native broad-leaved forest than under Chinese fir plantations,and higher under the first than under the second generation plantation.The content of soil active organic carbon (SAOC),microbial biomass carbon (MBC),water-soluble organic carbon (WSOC) and water-soluble carbohydrate (WSC) was 18.79 g穔g-1,421.7 mg穔g-1,252.2 mg穔g-1 and 136.3 mg穔g-1 under the first generation plantation of Chinese fir,and 22.31 g穔g-1,800.5 mg穔g-1,361.1 mg穔g-1 and 220.1 mg穔g-1 under the native broad-leaved forest,respectively.The corresponding values under the second generation plantation of Chinese fir were 73.6%,87.9%,66.3% and 53.2% of those under the first generation plantation of Chinese fir.The results also indicated that there existed some extent correlations among the active fractions of soil organic matter,and higher correlations between soil microbial biomass carbon and other active fractions of soil organic matter.
    Microbial diversity in continuously planted Chinese fir soil
    LI Yanmao, HU Jiangchun, ZHANG Jing, WANG Silong, WANG Shujin
    2005, 16(7):  1275-1278. 
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    The study on the microbial diversity of 1st,2nd,3rd and 4th generation Chinese fir soil at Huitong Forest Experimental Station showed that with the increase of generation,the numbers of bacteria and actinomyces decreased markedly,while that of fungi increased evidently.It was found by PCR and DGGE that the bacterial diversity changed slightly and its genetic similarity among different generations reached 87%,but the fungal diversity reduced and its genetic similarity was only 45%.The numbers of pathogenic and deleterious fungi increased markedly with increasing Chinese fir generations.
    Effects of different de-farming and reafforestation patterns on changes of soil fertility quality in karst region of southwestern China
    LONG Jian, DENG Qiqiong, JIANG Xinrong, LIU Fang
    2005, 16(7):  1279-1284. 
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    A ten-year fixed site harnessing was conducted in the severely eroded karst region of Ziyun County,Guizhou Province by adopting four different de-farming and reafforestation patterns,and the properties of soil chemistry,soil microbiology,and soil enzymology after harnessing were determined in 2003.The results showed that the total amount of soil microbes and the individuals of bacteria,fungi and actinomyces were increased obviously,the activities of soil hydrolytic and oxidoreductive enzymes and the soil respiration rate enhanced evidently,and the storage of soil nutrients as well as their supplying intensities promoted pronouncedly,demonstrating that the soil quality in all adopted patterns was improved in varying degrees.The values of soil integrated fertility index (IFI) had an increasing trend.Therefore,proper biological measures and essential supplementary engineering measures were effective in improving the soil fertility quality of severely degraded karst region.
    Spatial variability of slope land soil solute transport parameters
    ZHENG Jiyong, SHAO Mingan, ZHANG Xingchang, LI Shiqing
    2005, 16(7):  1285-1289. 
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    In this paper,the transport parameters of chlorine in a slope land soil were determined in situ by fitting breaking-though curve,and the spatial variability of the parameters in a 41 m×5 m runoff plot was analyzed by using traditional and geo-statistics.The results showed that the average pore-water velocity increased gradually from the top to the bottom of the slope,and the diffusive-dispersive coefficient (D) had no remarkable variation within 20m away from the top but gradually increased with the distance beyond 20m.The dispersivity (α) had the same characteristics as D.The pore-water velocity (v) had a floating feature on the slope,while parameters D and α showed obvious spatial correlation characteristics,the range of the spatial correlation being 21m and 10m,respectively.
    Correlation between inhibition activity of endophytic fungus from Euphorbia pekinensis and its host
    DAI Chuanchao, YU Boyang, ZHAO Yuting, YANG Qiyin, JIANG Jihong
    2005, 16(7):  1290-1294. 
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    To develop endophytic fungi resources from medicinal plants,this paper studied the correlation between endophytic fungus Fusariium sp.E5 from Euphorbia pekinensis and its host through analyzing the inhibition activity of this pathogen.An endophytic strain S12 (Alternaria sp.) from Sapium sebiferum was used as contrast.The results showed that E5 had an inhibitory effect on the host,while S12 and E.pekinensis extract didn't have it.The inhibition activity of E5 could be stimulated by the extract of host leaf,and its inhibitory effect could only be found when it was cultured with enough oxygen.The inhibition activity was affected by pH,temperature,and ultra-violet.These characters of endophytic fungus E5 showed a good correlation with its host,and this correlation was mutualism.
    Effects of elevated CO2 concentration on rhizosphere soil microbes under Pinus koraiensis and Pinus sylvestriformis seedlings
    JIA Xia, HAN Shijie, ZHOU Yumei, ZHANG Junhui, ZOU Chunjing
    2005, 16(7):  1295-1298. 
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    The study showed that under Pinus sylvestriformis seedlings,the amount of rhizosphere soil bacteria,but not fungi and actinomyces,increased significantly (P≤0.001) with CO2 enrichment (700 and 500 μmol·mol-1),and the same (P≤ 0.001) was under Pinus koraiensis seedlings,with the exceptions of 700 μmol CO2·mol-1 in August and 500 μmol CO2·mol-1 in July,compared to the ambient chamber and the ambient in each month.No significant effect of elevated CO2 was found on the amount of rhizosphere soil fungi except in September (P≤0.001),and the response of actinomyces to elevated CO2 was also insignificant.
    N2O emission factor for agricultural soils
    LU Yanyu, HUANG Yao, ZHENG Xunhua
    2005, 16(7):  1299-1302. 
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    Based on the direct measurements of annual N2O emission from 207 field experiments reported in literatures between 1982 and 2003,this paper established a database of annual N2O emission from agricultural fields.Correlation analysis indicated that the N2O emission from agricultural soils was significantly correlated with climatic factors temperature and precipitation,while no significant correlations were observed between N2O emission and edaphic parameters pH,organic carbon and nitrogen.According to the definition of N2O-N emission factor and its quantification by the Intergovernmental Panel on Climate Change,the N2O-N emission factor was modified by annual mean temperature and annual precipitation,respectively.The results suggested that the modification with precipitation might significantly reduce the estimated error of N2O emission by about 16%,while that with temperature did not reduce the error,in comparison with the default emission factor by the Intergovernmental Panel on Climate Change.
    Effects of organic manures on CO2 and CH4 fluxes of farmland
    DONG Yuhong, OUYANG Zhu
    2005, 16(7):  1303-1307. 
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    This paper studied the effects of chicken manure,swine waste and cattle manure on the CO2 and CH4 fluxes of a farmland planted with summer maize.The results showed that the CO2 flux had the same trend under different organic manure application,which was influenced by soil temperature and soil water content.The flux was significantly related with air temperature,soil surface temperature and soil temperature (P<0.05).When soil temperature was not a limiting factor,soil water content was significantly related with soil CO2 flux.At most maize growth stages,soil was a sink of CH4.The variation of CH4 source-sink was influenced by environmental factors,but the correlation was not significant.The mean seasonal flux of CO2 was from 0.5124 to 0.8518 g穖-2-1,and that of CH4 was from-0.0068 to -0.0484 mg穖-2-1.Compared with CK2,maize planting and organic manure application enhanced CO2 emission.The application of organic manures inhibited the CH4 uptake by soil,and higher application rate had a higher inhibitory effect.
    Geostatistics analysis on spatial patterns of Myzus persicae and Erigonidium graminicola in plum orchard
    DING Chengcheng, ZOU Yunding, BI Shoudong, GAO Caiqiu, LIU Xiaolin, CAO Cuanwang, MENG Qinglei, LI Changgen
    2005, 16(7):  1308-1312. 
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    Investigations on the spatial construction and distribution of Myzus persicae and Erigonidium graminicola in a plum orchard were conducted from March 2003 to November 2003.The results indicated that the semivariogram of Myzus persicae could be described by spherical model,except on June 27 and November 22,which should be described by lined model,and that of Erigonidium graminicola could be described by spherical model,except on May 21,May 31,October 19 and November 22,which should be described by lined model.It could be concluded that the amount and spatial distribution of Erigonidium graminicola was closely related to those of Myzus persicae.
    Effects of corn cultivar on Tetranychus truncatus Ehara (Acarina:Tetranychidae) population parameters
    PANG Baoping, LIU Jiaxiang, ZHOU Xiaorong, ZHANG Ruifeng
    2005, 16(7):  1313-1316. 
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    The laboratory study at 28 ℃ showed that on four different corn cultivars,the durations of ovum,nymph and pre-oviposition,adult longevity,fecundity,egg production per day,net reproductive rate (R0),finite rate of increase (λ),intrinsic rate of increase (rm),mean generation time (T),and the days needed to double population size (DDP) of Tetranychus truncatus were significantly different.The hatching rate on Zea mays cv.Zhongdan 2,Nongda 108,Chidan 202 and Badan 3 was 95.8%,94.0%,90.0% and 84.0%,and the survival rate on these cultivars was 90.5%,86.0%,84.0%,and 72.0%,respectively.All the survival curves were of Deevey Ⅰ.The net reproductive rate (R0) was the highest on Zhongdan 2,and the lowest on Badan 3.The mite displayed a decreasing preference in order of Zhongdan 2> Nongda 108> Chidan 202> Badan 3.
    Controlling effects of plant extracts and pesticides on Myzus persicae and Lipaphis erysimi populations
    ZHOU Qiong, LIANG Guangwen, ZENG Ling, SHEN Shuping, CEN Yijing
    2005, 16(7):  1317-1321. 
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    This paper studied the controlling effects of Xanthium sibiricum and Syngonium podophyllum ethanol extracts,mobile oil emulsion and 0.3% azadirachtin EC on Myzus persicae and Lipaphis erysimi populations both in laboratory and in field.The results showed that in laboratory,X.sibiricum extract was the key deterrent to Myzus persicae,while sprayed it with S.podophyllum extract and with petroleum spray oil or 0.3% azadirachtin EC,the deterrent effect could be improved.As for pterigota Lipaphis erysimi,the extracts of the two plants were the main deterrents,and their interference effect was non-linear.In field,S.podophyllum extract had a stronger deterrent effect when sprayed independently.L.erysimi population could be successfully controlled by the mixtures of plant extracts and insecticides,with an efficiency of 95.7%.The best treatment against M.persicae population was X.sibiricum extract,with an efficiency of 87%,while S.podophyllum extract mixed with 0.3% azadirachtin EC,and X.sibiricum extract mixed with 0.3% azadirachtin EC had an efficiency of >80%.
    Roles of olfaction and vision in orientation behavior of adult Campylomma chinensis Schuh (Hemiptera:Miridae) toward Lantana plants (Verbanaceae)
    WU Weijian, GAO Zezheng, YU Jinyong, LIANG Guangwen
    2005, 16(7):  1322-1325. 
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    Investigations were carried out on the orientation behavior of adult Campylomma chinensis Schuh (Hemiptera:Miridae) toward plant hosts Lantana camara,L.camara cv.‘Flava',and L.montevidensis (Spreng.) Briq.(Verbanaceae).Surveys on three Lantana plants showed that the distribution of C.chinensis in inflorescences was not related to floral color (partial correlation coefficient was 0.240,P=0.147,n=40),but to the number of Thrips hawiiensis Morgan (partial correlation coefficient was 0.512,P<0.0001,n=40) and the flowers per inflorescence (partial correlation coefficient was 0.451,P<0.0001,n=40).In a colour preference experiment,no adult C.chinensis attracted to six different colour plates in longan field.The testing results of four-armed olfactometer indicated that adult C.chinensis had a significantly higher preference for L.camara.It was concluded that olfactory stimuli played an important role in searching for plant hosts of C.chinensis.Solid phase micro-extraction (SPME) and GC-MS were employed to analyze the volatiles compounds of Lantana,and seven same chemical constituents were detected from the volatiles of three Lantana plants inflorescence.
    Relationships of Aulacophora beetles feeding behavior with cucurbitacin types in host crops
    YANG Xiao, KONG Chuihua, LIANG Wenju, ZHANG Maoxin, HU Fei
    2005, 16(7):  1326-1329. 
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    Aulacophora fermoralis chinensis and Aulacophora cattigarensis are the two related Aulacophora beetles,but their host selectivity and feeding behavior are significantly different.A.fermoralis chinensis usually feeds upon Cucumis sativus and Cucurbita moschata,but never upon Luffa acutangula,Momordica charantia and Citrullas lanatus.Its feeding behavior on hosts is to snip a circular trench on their leaves,and then,to feed the leaf tissues isolated by the trench.On the contrary,A.cattigarensis only feeds L.acutangula,and its trenching behavior rarely occurs.This study showed that the host selectivity and feeding behavior of the two beetles were significantly correlated with the types of cucurbitacin biosynthesized by host melon crops.C.sativus and C.moschata might be induced to produce cucurbitacin I by A.fermoralis chinensis feeding,and this compound was responsible for feeding deterrent on A.fermoralis chinensis.Therefore,the feeding behavior of A.fermoralis chinensis was to block the translocation of cucurbitacin I to feeding sites.M.charantia and C.lanatus contained deterrent cucurbitacin D,and thus,both beetles never fed upon them,while L.acutangula contained stimulants cucurbitacin B and E,and made A.cattigarensis directly feed upon it without trenching.The results suggested that the taste responses of insects on specific allelochemicals from plants may play an important role in host selectivity and feeding behavior.
    Population dynamics of Bactrocera dorsalis (Diptera:Tephritidae) in Xishuangbanna of Southern Yunnan
    YE Hui, LIU Jianhong
    2005, 16(7):  1330-1334. 
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    In the study,an all year round monitoring through lure-traps in 1997,2000 and 2003 was conducted on the population dynamics of oriental fruit fly,Bactrocera dorsalis (Diptera:Tephritidae) in Xishuangbanna of Southern Yunnan,and the factors in relation with its population fluctuation,including temperature,rainfall,and host species were analyzed.The fruit fly occurred year-round in Xishuangbanna,with a low population level from November to February,and increased steadily from March to July or August.An increasing peak appeared in July or August,depending on the rainfall amount in that year.Afterwards,the fly population declined markedly until to October.Temperature,rainfall,and host fruits were supposed to be the major factors affecting the population fluctuation.The monthly average temperature in Xishuangbanna was in the ranges suitable for the development and reproduction of the fly,but the monthly average minimum temperature from December to February appeared to be lower than the suitable temperature,which was suggested to be responsible for the low populations in the winter months.Rainfall was another essential factor affecting population fluctuation.The population was depressed when the monthly rainfall amount was lower than 50 mm,but increased when the amount ranged between 100 and 200 mm.Under conditions the monthly rainfall amount was higher than 250 mm,the fruit fly population was reduced markedly,which explained the decreasing population in July or August when the heavy rain occurred.Mango,orange,pear,longan,and peach were the main host species of the fly,among which,mango and longan were most preferred by the fly.Therefore,their planted area,fruiting period and productivity exerted essential effects on the fly population fluctuation,and regarded as another major factor affecting the fly population in this area.
    Hydrochemical characteristics of three kinds of wetland in Gongbiela Basin
    MAN Xiuling, CAI Tijiu
    2005, 16(7):  1335-1340. 
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    The study on the hydrochemical characteristics of three representative kinds of wetland in Gongbiela Basin showed that in the water of test wetlands,HCO3- was the dominant anion,accounting for 81.91%~85.46% of total anions,and Ca2+ was the dominant cation,accounting for 56.80%~69.32% of total cations.The hydrochemical type belonged to that of bicarbonate calcium.In the three kinds of wetland,water pH ranged from 6.2 to 7.1,mineralization degree ranged from 112.56 to 461.23 mg·L-1,and hardness ranged from 14.31 to 148.53 mg·L-1.On the whole,the water quality of the wetlands met the grade 1 and grade 2 national environmental water quality standards,but the Fe and Mn contents exceeding the standards influenced the water resource quality of this area.The spatial and temporal changes of hydochemical characteristics of the wetlands and the trace element contents in the water were also discussed and analyzed.
    Zooplankton in north branch waters of Changjiang Estuary
    XU Zhaoli
    2005, 16(7):  1341-1345. 
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    Based on the investigation data during the high-water (July,2003) and low-water (January,2004) periods,a causal analysis was made on the variation of zooplankton distribution in the north branch waters of the Changjiang Estuary.The results showed that in high-water period,the average of zooplankton biomass was 234.38 mg穖-3,being 141.35 mg穖-3 in flood tide and 327.40 mg穖-3 in ebb tide,while in low-water period,it was 188.81 mg穖-3,being 184.69 mg穖-3 in flood tide and 192.93 mg穖-3 in ebb tide.The biomass increased from the east to the west in flood tide,but a contrary trend was observed in ebb tide.The species number did not change obviously both in flood tide and in ebb tide.The value of diversity index (H') was higher in flood tide than in ebb tide.In high-water period,the biomass near the north shore was higher than that near the south shore,but it was contrary in the ebb tide.The difference between the waters of two shores was not obvious in low-water period as in high-water period,though the trend of biomass variation was similar.The variation of zooplankton distribution in the north branch waters of the Changjiang Estuary had a close relation with the seasonal changes of zooplankton biomass outside the Changjiang Estuary and the tide,but not significantly related with the Changjiang runoff water.Coriolis force accounted for the difference of zooplankton biomass in the waters of two shores via tide movement.
    Recruitment dynamics of bloom-forming cyanobacteria in Meiliang Bay of Taihu Lake
    ZHANG Xiaofeng, KONG Fanxiang, CAO Huansheng, TAN Jiankang, TAO Yi, WANG Meilin
    2005, 16(7):  1346-1350. 
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    A collection trap was installed on the sediments in Meiliang Bay of Taihu Lake during the period from March to June to investigate the recruitment of phytoplankton,and cyanobacteria in particular.The algal abundance in the trap was monitored,and compared with that in water column and surface sediments.The results showed that the algal recruitment was related to the temperature,irradiance,DO content,and oxidation-reduction potential (ORP) in surface sediment.After over-wintering on the sediments,the colonies of cyanobacteria experienced a prior developmental process before re-invasion of the water column.During the investigation period,the recruitment rates of chlorophyll a and b and PC were 59.84%,76.83% and 466.98%,and the recruitment amounts accounted for 7.18%,3.71% and 9.33% of their maximum pelagic counterparts in water column,respectively.These results showed that shallow lake was the important seed bank to the pelagic populations,and water bloom was formed as the result of the recruitment and biomass accumulation of cyanobacteria.
    Accumulation of non-point source pollutants in ditch wetland and their uptake and purification by plants
    JIANG Cuiling, FAN Xiaoqiu, ZHANG Yibing
    2005, 16(7):  1351-1354. 
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    The study on the vertical and horizontal distribution of organic matters and total nitrogen (TN) in the sediment of ditch wetland naturally grown with reed (Phragmites communis) and wild rice (Zizania latifolia) showed that the sediment below 40 cm depth had a significant effectiveness in retaining and accumulating organic matters and TN,but in its surface layer,this effectiveness varied largely with seasons,and the maximum was more than twofold of the minimum.TN was highly correlated with organic matters,the correlation coefficient being 0.9876 in reed wetland and 0.9335 in wild rice wetland,and in water phase,it was positively related to NH4+-N and NO3-N,indicating that the main composition of TN was organic N,and the mineralization of organic N was the sources of inorganic N.The harvest of reed in each autumn could take away 818 kg穐m-2 of N and 103.6 kg穐m-2 of P,and that of wild rice could take away 131 kg穐m-2 of N and 28.9 kg穐m-2 of P.Zizania caduciflora had a high assimilation ability of nutrients.Its cultivation in ditch wetland to replace wild helophytes would be a good approach to attain higher absorbing ability of N and P,and to resolve the secondary pollution problem of emerged plants,because farmers could harvest it voluntarily.
    Impacts of petroleum-containing wastewater irrigation on microbial population and enzyme activities in paddy soil of Shenfu irrigation area
    LI Hui, CHEN Guanxiong, YANG Tao, ZHANG Chenggang
    2005, 16(7):  1355-1359. 
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    The study showed that the upper reaches of main petroleum-containing wastewater irrigation channels had the highest accumulation and distribution of total petroleum hydrocarbon (TPH) (5 213.37 mg穔g-1 dry soil),and the CFU of soil bacteria and fungi was increased with increasing soil TPH concentration,the correlation coefficient being 0.928 (P<0.001) and 0.772 (P<0.05),respectively.The activities of soil dehydrogenase,catalase and polyphenoloxidase had a significantly positive correlation with soil TPH concentration,their correlation coefficient being 0.974 (P<0.001),0.957 (P<0.001) and 0.886 (P<0.001),respectively,while soil urease activity showed a significantly negative correlation (P=0.002),which could be used as the most sensitive indicator of petroleum contamination.The substrate-induced respiration (SIR) of polluted soil was significantly correlated with soil TPH concentration (P<0.001),dehydrogenase activity (P<0.001),and heterotrophic bacterial CFU (P=0.006).
    Effects of environmental factors on Cd biotoxicity and phytochelatins production in Triticum aestivum
    SUN Qin, YUAN Xinfang, WANG Xiaorong
    2005, 16(7):  1360-1365. 
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    In this paper,a solution culture experiment was conducted to study the effects of environmental factors on Cd biotoxicity and phytochelatins (PCs) production in wheat.The results showed that Cd stress had significant inhibitory effects on wheat growth and PCs overproduction.The Cd biotoxicity and Cd uptake by wheat were affected in varying degrees by soil pH,Ca and S,and the levels of PCs production in root were consistent with the changes of Cd biotoxicity.Furthermore,the Cd biotoxicity was decreased with increasing P supply,coinciding with the decrease of PCs level in root.Mg had no obvious effect on both Cd biotoxicity and PCs level in root.The present results further confirmed that the induced PCs production level by Cd was related to Cd biotoxicity in plant,suggesting that PCs could be a promising biomarker for estimating Cd phytotoxicity.
    Effects of urbanization on landscape pattern of Beijing
    SUN Yajie, WANG Qingxu, LU Zhaohua
    2005, 16(7):  1366-1369. 
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    Landscape pattern of Beijing urban areas within the six-ringed road was classified based on 1997 and 2002 remote sensing data. The indices from landscape level were computed using Fragstats3.3 to study the landscape pattern change of Beijing urban areas from 1997 to 2002.The results showed that the number of patches increased by 106.6%,the mean patch area decreased by 51.6%,the splitting index increased by 94.3%, and the landscape diversity index increased by 17.8%.The landscape pattern tended to be fragmentized and diversified in those five years.The reason of this change was the increased need for construction land due to the growing population and the improvement of living standard.Landscape pattern change of Beijing might influence the changes of substance flow and energy flow.It also provided some fundamental landscape scale data and some suggestions for development and planning of Beijing city.
    Ecological footprint and available ecological capacity in Chongqing region
    SUN Fan, MONG Linbing
    2005, 16(7):  1370-1374. 
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    Based on the statistical data of Chongqing,the ecological footprint of Chongqing was calculated in this paper.The results showed that the per capita ecological footprint was 1.653566 hm2,per capita ecological capacity was 0.280393 hm2,and ecological surplus of deficit was 1.373173 hm2.The per capita ecological footprint was 0.5335 hm2 (47.64%) higher but the per capita ecological capacity was 0.5196 hm2 (64.95%) lower,and the ecological surplus of deficit was about 3.43 times of the average national level.These results showed that the ecological footprint of Chongqing was beyond the available ecological capacity,and its social and economic development was not sustainable.The strategies on reducing ecological deficit in this region,such as reducing ecosystem population,increasing public finance income,and controlling environmental pollution,were also put forward.
    Animal immunocompetence and its effect on population regulation and life history trade-off
    ZHANG Zhiqiang, WANG Dehua
    2005, 16(7):  1375-1379. 
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    Immunocompetence is a common conception in biomedical and animal sciences,and refers to the ability of organisms against diseases.In recent years,a new field,ecological immunology,has been received much attention,which deals with the variation of immunocompetence in wildlife by immune methods.This paper introduced the conception of immunocompetence,the factors affecting its performance,and its roles in regulating animal population dynamics.Some hypotheses on population regulation in small mammals,such as immunocompetence handicap hypothesis,immunocompetence selection hypothesis and winter immune enhancement hypothesis were summarized.The relationships among energy metabolism,endocrine controlling mechanism and immune system were introduced,and the recent progress on immunocompetence and life history trade-off was analyzed.The trade-off between survival and immunocompetence,as well as between reproduction and immunocompetence were discussed,and some developing perspectives and new problems in ecological immunology were proposed.
    Bacterial flora composition and its dynamics in tidal-flat Sinonovacula constricta aquaculture area
    JIN Shan, XUE Chaobo, WANG Guoliang, LU Tongxia, WANG Yinong, CHEN Yiner
    2005, 16(7):  1380-1382. 
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    In this study,the bacteria from the mud in tidal-flat Sinonovacula constricta aquaculture area were isolated each month from March to December,2002,and the temporal and spatial distribution of heterotrophic bacteria,ammonifying bacteria,denitrifying bacteria,and sulphate reducing bacteria were analyzed.The results showed that all the 515 isolated bacteria mainly belonged to 1 family and 13 genera.The bacterial flora in different layers of the mud was almost consistent,while the composition was different.The predominant genera were Clostridium,Bacillus,Corynebacterium,Photobacterium,and some Enterobacteriaceae.The number of heterotrophic bacteria in the surface layer and the bottom fluctuated in 7.6×103 cfu·g-1~2.0×105 and 1.6×103~1.0×105 cfu·g-1,ammonifying bacteria fluctuated in 1.5×106~9.0×107 and 9.0×105~1.0×107 cfu·g-1,denitrifying bacteria fluctuated in 9.0×103~4.0×106 and 5.0×102~1.9×106 cfu·g-1,and sulphate reducing bacteria fluctuated in 5.0×104~5.0×106 and 1.9×104~2.0×106 cfu·g-1,respectively.The detection rates of ammonifying bacteria,denitrifying bacteria and sulphate reducing bacteria in the mud were all 100%,and these bacteria increased significantly in the second half of the year,indicating that the environment of the Sinonovacula constricta aquaculture area was deteriorated due to the accumulation of NH3,nitrite and H2S,and it is important to regulate the breed capacity and redistribute the breeding environment.