Loading...
Welcome to Chinese Journal of Applied Ecology! Today is Share:

Table of Content

    25 October 1995, Volume 6 Issue 4
    Articles
    N2O emission from woody plants and its relation to their physiological activities
    Yang Sihe, Chen Guanxiong, Lin Jihui, Wu Jie, Ma Yueqiang
    1995, 6(4):  337-340. 
    Asbtract ( 1435 )   PDF (299KB) ( 386 )  
    Using gas exchange measurement system, the photosynthesis, respiration and stomatal conductance of several coniferous and broadleaved tree species were measured simultaneously.Under conditions of low and middle illumination, N2O emission is found from leaves or needles of tested tree species.There is no significant relationship between N2O flux and photosynthetic rate.The N2O absorption by plants is also observed.Its emission rate is increaed with increasing temperature and respiration rate.Stomata is probably the main pathway for N2O emission.
    Comparative study on internal and external nutrient cyclings or poplar tree under different fertilizations Ⅰ.Effect of fertilization on biomass or poplar tree and its internal and external cypling of N before and after leaf fallen
    Yu Wantai, Chen Xin, Zhang Lu, Yin Xiuyan, Shen Shanmin
    1995, 6(4):  341-345. 
    Asbtract ( 1549 )   PDF (294KB) ( 554 )  
    Fertilization can significantly increase the biomass of poplar tree, especially that of its root.Whether fertilization or not, leaf is the major N pool for the growing poplar tree, and about 63% of N in it is transfered into trunk, branch and root before its fallen.Fertilization can increase the gross flux of N by 46%, and change the structure of N cyce in poplar tree.Comparing with control, fertilization can increase the rate of internal flux vs.gross flux from 0.37 to 0.45.
    Comparative study on internal and external nutrient cyclings or poplar tree under different fertilizations Ⅱ.Effect of fertilization on concentration and storage of major nutrients in poplar leaves before and after leaf fallen
    Chen Xin, Yu Wantai, Zhang Lu, Yin Xiuyan, Shen Shanmin
    1995, 6(4):  346-348. 
    Asbtract ( 1659 )   PDF (243KB) ( 541 )  
    Poplar leaf can transfer large amount of organic matter from it into trunk, branch and root before its fallen, the output rate in unfertilization treatment being larger than that in fertilization one.Papplication does not leads its luxury absorption by popalr tree.Fertilization can increase the flux of external cyclings of major nutrient, and the output of Pand Kin poplar leaf before its fallen is 10% lower than control.
    Transpiration characteristics of tea tree
    Tao Hanzhi, Zhou Liangliu, Fang Yiping, Cheng Zhuyu, Zhou Jianjun
    1995, 6(4):  349-354. 
    Asbtract ( 1718 )   PDF (452KB) ( 442 )  
    The transpiration rate and stomatal conductance of tea tree are varied with its cultivars and leaf position.Cultivars with stronger drought resistance have a lower stomatal conductance, and fish leaf has a similar or higher transpiration rate and stomatal conductance than true leaf.The transpiratidn rate of tea leaf is highest in summer and autumn, second in spring, and lowest in winter.On clear days, the diurnal fluctuation of transpiration rate and stomatal conductance of tea leaves shows a single peak, being highest before and after noon, and related significantly to photon flux density, leaf temperature and vapor pressure deficiency.Photon flux density has a significant effect on transpiration rate and stomatal conductance.
    ESM observation of secretory salt structure in Limonium bicolor leaf
    Lu Jingmei, Li Jiandong, Hu Ailin, Li Xiliang
    1995, 6(4):  355-358. 
    Asbtract ( 1756 )   PDF (451KB) ( 685 )  
    Studies on the structure of salt gland of Limonium bicolor leaf show that being different with other halophytes, Limonium bicolor flower-like salt glands in its lower epidermis of leaf, which consist of basic and cap cells.The salt release of plant is relied on the salt-secreting holes of salt gland and the broken of basic cells, indicating that this plant has a highly evolved structure of two-ways secreting salt, which makes the plant can grow on saline-alkali soil without any suffering from salt damage.
    Characteristics of soil fauna in Aneurolepidium chinense grassland
    Guo Jixun, Zhu Tingcheng
    1995, 6(4):  359-362. 
    Asbtract ( 1386 )   PDF (245KB) ( 434 )  
    Studies on the characteristics of soil fauna in Aneurolepidium chinense grassland show that it can be classified into 14 orders belonging to 4 phyla and 6 classes.Its horizontal distribution pattern is in the order of weeds community>Aneurolepidium chinense conmmunity >Calamagrostis epigeios community>Ulmus pumila sparse woods>Puccinellia tenuiflora community>Suaeda glauca community.The seasonal variation of its amount and biomass is similar and both of them have a peak value in August.Its amount is decreased with increasing soil depth, and occupies 50% of the total in 0-10cm soil later.
    Physiological effects of humic acids on drought resistance of wheat
    Cheng Fujiu, Yang Daoqi, Wu Qingsheng
    1995, 6(4):  363-367. 
    Asbtract ( 2353 )   PDF (419KB) ( 472 )  
    Under dry climate condition, spraying humic acids can decrease the loss of soil moisture and enhance the water retention ability of wheat leaf.The activities of superoxide dismutase (SOD) and catalase (CAT) in leaf cells are significantly increased, but the MDA content and leakage rate of electrolyte are significantly decreased, and hence, the chlorophyll decomposition is retarded, the photosynthetic rate and grain filling intensity are increased.the plant senescence is retarded, the drought resistance of wheat is enhanced and its thousand-grain weight is increased.
    Synergistic effect of urease inhibitor and nitrification inhibitor on urea-N transformation and N2O emission
    Chen Lijun, Shi Yi, Li Ronghua, Hu Liansheng, Zhou Likai
    1995, 6(4):  368-372. 
    Asbtract ( 1572 )   PDF (376KB) ( 608 )  
    Based on incubation tests under normal soil water condition and waterlogging,this paper discussed the effect of different combinations of urease inhibitor hydroquinone and nitrification inhibitors dicyandiamide and calcium carbide on the hydrolysis of soil urea, the adsorption,oxidation and volatilization of its released ammonia.as well as the emission of produced N2O.It's indicated that hydroquinone in cooperation with dicyandiamide can both delay the hydrolysis of soil urea and make its released ammonia be conserved in soil witll more amount and longer period,and decrease the accumulation of soil nitrate, the loss of ammonia volatilization and the formation of nitrous oxide, which shows .that there probably exists a definite synergistic effect between urease inhibitor and nitrification inhibitor,and,to make full use of this effect will be beneficial to promote the efficiency of urea application and decrease the damage of its Nloss and environmental pollution.
    A preliminary study on N2O and CH4 emissions from differentsoils on northern slope of Changbai Mountain
    Xu Hui, Chen Guanxiong, Ma Chengxin
    1995, 6(4):  373-377. 
    Asbtract ( 1587 )   PDF (369KB) ( 383 )  
    The fluxes of N2O and CH4 from tundra soil, soddy forest soil, brown coniferous forest soil and dark brown forest soil on northern slope of Changbai Mountain are measured in situ by chamber technique from June and August, 1994.The results show that all of the soils studied are the source of N2O, and the sink of CH4.The N2O flux is in the range of 6.17 and 12.33 μg·m-2·h-1, while the CH4 flux is between -85.63 and -7.58μg·m-2·h-1.There is a trade-off between N2O emission and CH4 uptake.Laboratory experiments show that upper soil layer (0-6cm) has the highest denitrification activity, which has a significant difference among different soils.The uptake of CH4 by dark brown forest soil mainly occurs in upper soil layer (0-12cm).
    CH4 and N2O emission from a rice field and effect of Azolla and fertilitaion on them
    Chen Guanxiong, Huang Guohong, Huang Bin, Wu Jie, Yu Kewei, Xu Hui, Xue Xiaohua, Wang Zhengping
    1995, 6(4):  378-382. 
    Asbtract ( 1381 )   PDF (301KB) ( 572 )  
    CH4 and N2O emission from a rice field in northeast China are monitored simultaneously and systematically by using chamber technique to estimate their fluxes from rice fields and to understand the relationship between these two gases emissions.The results show that CH4 emission from rice field in northeast China is much lower than that in south China, with a daily average emission of 0.079·m-2 and total seasonal emission of 7.4g·m-2.Rice fields almost do not emit or deposit N2O during flooding period, but substantially emit it (average flux 59 μgN2O.m-2·h-1) during non-flooding period.CH4 and N2O emissions are greatly enhanced by Azolla and fertilization.Atrade-off between CH4 and N2O emissions is observed, which should be considered when mitigation options for reducing greenhouse gas emission are proposed.
    N2O and CH4 fluxes from typical upland fields in northeast China
    Huang Guohong, Chen Guanxiong, Wu Jie, Huang Bin, Yu Kewei
    1995, 6(4):  383-386. 
    Asbtract ( 1669 )   PDF (262KB) ( 461 )  
    Closed chamber measurements of N2O and CH4 fluxes from soybean and maize fields at Shenyang Ecological Experimental Station show that the emission of N2O has significant diurnal and seasonal variations, and mainly occurs in the growing period of crops.N2O is also released from soil during thawing and after harvest.In addition, the net emission of CH4 from soybean and maize fields is very small, and hence, upland field as the sink or source of atmospheric CH4 is not significant.
    Role of several upland crops in N2O emission from farmland and its response to environmental factors
    Yu Kewei, Chen Guanxiong, Yang Sihe, Wu Jie, Huang Bin, Huang Guohong, Xu Hui
    1995, 6(4):  387-391. 
    Asbtract ( 1409 )   PDF (415KB) ( 524 )  
    The role of upland crops in N2O emission from farmland is evaluated by measuring N2O flux from several farniland ecosystems with closed chamber method,comparing with N2O flux from bare field.The effect of environmental factors on N2O flux its investigated by experiments in field and laboratory.The results show that there exists an emission peak of diurnal N2O flux both in the morning and in the afternoon from soybean field,but only one peak from spinach and spring wheat fields,which occurs in the afternoon and dusk,respectively.Plantation of soybean,which is less fertilized,strongly promotes the N2Oemission from farmland with an average emission flux of 83.8 μg·m-2·h-1.Bare field is a weak N2Osource,whose emission rate is 1.2 μg·m-2· h-1 in average,and can be a sink of atmospheric N2O from September to October,the flux rate being-11.9μg·m-2·h-1.The variation of illumination has a significant influence on N2O flux from crop.Higher emission of N2O from aroid occurs under weak illumination.
    Rhizospheric effect of organic material on coastal saline soil in Huanghe River Delta Ⅱ.soil salinity effect
    Wu Longhua, Zhang Sujun, Zhang Xiulan
    1995, 6(4):  392-396. 
    Asbtract ( 1395 )   PDF (430KB) ( 470 )  
    The effect of composted organic material on the salinity of coastal saline paddy soil and its submerged layer and the uptake of elements by rice plant is studied with rhizobox method.The results show that under no drainage condition.the application of organic material increases the salinity of soil and its submerged layer, but decreases the accumulation of salts in paddy rice rhizosphere.It can enhance the uptake of K, Ca and Mg, and decrease that of Na by rice plant.
    Translocation and transformation of supplemented trace Zn in soil
    Zou Bangji, Li Shuding, Zhu Xi
    1995, 6(4):  397-400. 
    Asbtract ( 1506 )   PDF (348KB) ( 436 )  
    The translocation and transformation of supplemented trace Zn in drab soil is studied with radioactive isotope tracer and chemical fractional extraction methods.It is found that at initial stage, most of soil 65Zn is in exchangeable and carbonate bound forms, and less in residual form.In the following 2 weeks, carbonate bound form is largely transformed into CFeOX and RES forms.After 4 months, MnOX and CFeOX forms are tended to transform into RESform.6 months later, the bulk of 65Zn is still in the labiler CARB and AFeOX forms.
    Existent forms and their diffusion of Zn supplemented into drab soil
    LI Shuding, Zou Bangji, Zhu Xi
    1995, 6(4):  401-405. 
    Asbtract ( 1470 )   PDF (379KB) ( 318 )  
    Studies on existent forms of Zn supplemented into drab soil with tracer technique and chemical sequential extraction procedure show that the amount of exchangeable and carbonate bound 65Zn occupies 63-72% of the total soil Zn.The intensity factor of soil Zn is increased with the increasing amount of added Zn, and its diffusion coefficient (D) at 4 and 100% of soil moisture content is respectively 7.9×10-8 and 6.6 × 10-5cm2s-1. At 30 and 70% of soil moisture content,the average retention time of Zn in applied area is respectively 9 and 4 days,and its diffusion degree (σ2) is increased from 0 to 0.371.
    Bioassay of simazine in water and soil water solution using aquatic flowering plants as indicators
    Ou Ziqing, Ren Liping, Jia Liangqing, Zhang Hairong, Chang Shijun, Sun Tieheng
    1995, 6(4):  406-410. 
    Asbtract ( 1549 )   PDF (429KB) ( 403 )  
    A simple, rapid and sensitiye bioassay using aquatic flowering plants as indicators is used for measuring available photosynthesis-inhibiting herbicides (simazine) in water and soil water solution.This method is based on the effect of simazine on oxygen release of photosynthesis, which can be directly measured using an oxygen electrode, and with which, the amount of simazine can be calculated.Measurement can be made within 10 min of treatment.This method is capable of measuring a minimum simazine concentration of 0.02mg·L-1.Ceratophyllum oryzetorum is a better indicator than Ranunculus trichophyllus and Alisma planlago-aquatica.The mean recoveries of simazine by bioassay using C.oryzetorum are 96 to 100%, which is comparable to those (98 to 100%) obtained by C18 column extraction and HPLC measurement.
    Impact of high temperature stress on survival of Tn5 mutants or Rhizobium fredii and phenotypic expression of Tn5 in soil
    Lin Jishang, Cui Mingxue, Jin Suying, Li Ning, Li Mingqi, Zhao Wei, Zhang Xiaodong
    1995, 6(4):  411-416. 
    Asbtract ( 1574 )   PDF (2663KB) ( 324 )  
    Awild type and thyee transposon Tn5 insertion mutants of Rhizobium fredii were used to study their survival and Tns phenotypic expression in soil under optimum temperature (28 C)and temperature stress (40 C).Survival studies with sterile and nonsterile soils show that under optimum temperature (28 C), biotic factors inhibit the growth of mutant and wild type.But, there is no significant difference (P=0.01) between the surviving populations of wild type and Tn5 mutants.Under temperature stressed condition (40 C), both wild type and mutant populations decline rapidly, and some of the mutant cells (ON-2 and ON-3) can't express kanamycin resistance.These results suggest that high temperature is a harmful factor for the survival of bacteria and the phenotypic expression of Tn5 in soil.
    Behaviors of polycyclic aromatic hydrocarbons (PAHs) and heavy metals in soil-plant system
    Song Yufang, Sun Tieheng, Zhang Lishan, A. Yediler, G. Lorinci, A. Kettrup
    1995, 6(4):  417-422. 
    Asbtract ( 1483 )   PDF (498KB) ( 654 )  
    In order to understand the fate of PAHs and heavy metals in soil-plant system,the behaviors of PAHs and heavy metals in soil of land treartment system (LTS) at western Shenyang were studied.PAHs and heavy metals are accumulated in0-20cm soil layer, and can not be found below.The PAHs content is decreased from April to October, which shows that soil microbes play an important role in the degradation of PAHs, and the degradation rate is related to ecojogical structure of soil-plant system.Phenanthrene can be determined with a high concentration in the groundwater, which indicates the possibility of its migration downward.Willow can reduce and purify heavy metals.This study shows that strict control of pollutant load of PAHs and heavy metals in wastewater and rational design of ecological structure are the key points for avoiding the accumulation of PAHs and heavy metals in soil.
    Adsorption of polycyclic aromatic hydrocarbons on soils
    He Yaowu, Ou Ziqing, Sun Tieheng, Ayfer Yediler
    1995, 6(4):  423-427. 
    Asbtract ( 1839 )   PDF (352KB) ( 679 )  
    The adsorption of several polycyclic aromatic hydrocarbons (PAHs) on soils is studied in this paper.Through a continuous applying-sampling apparatus, the adsorption of fluoranthene and phenanthrene on soils from both China and abroad is measured without the interference of any other organic solvents.The results show that adsorption of fluoranthene and phenenthrene on soil correlated significantly with organic carbon contents of soils used as adsorbents.Investigations on the relations between LogKoc and molecular structure, LogKoc and physico-chemical characteristics of chemicals, such as octanol-water partition coefficients (Kow) and aquatic solubility (Sw) show that LogKoc is linearly correlated with LogSw, LogKow and the number of benzene loops in the molecular structure of PAHs.
    Effect of degraded products from mineral oil on translocation and transformation of Cd In soil-plant system
    Xiong Xianzhe, He Yongtian, Zhang Xuexun, Song Shenghuan, Wu Tiezheng, Li Ying
    1995, 6(4):  428-432. 
    Asbtract ( 1361 )   PDF (365KB) ( 366 )  
    Studies on the effect of palmitic acid, catechol and vanillic acid on behavior of Cd in soil show that the toxic concentration of catechol to rice plant is 100 mg·kg-1, and that of vanillic acid is 500 mg·kg-1.When the soil content of catechol is 5000 mg·kg-1, the concentration of Cd in rice grain is reduced to 0.008 mg·kg-1,and that in leached solution from soil column is lowered to 0.005 mg·L-1.All of these three organic compounds can increase the proportion of soil organic bound Cd,which occupies 48.71% of total id when the soil is amended with 5000rug·kg-1 catechol.
    Impact of heavy metal combined pollution on soybean growth and its integrated assessment
    Yu Guoying, Wu Yanyu, Wang Xin
    1995, 6(4):  433-439. 
    Asbtract ( 1670 )   PDF (514KB) ( 529 )  
    The impact of Cd,Pb,Cu, Zn and As combined pollution on soybean growth is studied with Hogland solution culture.The results show that under condition of combined pollution, the accumulation of heavy metals in root is in the order of As>Pb>Cu>Cd>Zn and that in stem and leaf is in the order of Cd>Cu>Zn>As>Pb.The type of their interaction is depended on the added concentration of elements and the proportion of coexistent ones.As and Cu are the main elements toxic to the growth of soybean.Relative ionic intensity is an effective index for indicating and controlling the integrated effect of combined pollution.
    Effect of modification treatments on behaviour of heavy metals in combined polluted soil
    Wang Xin, Wu Yanyu
    1995, 6(4):  440-444. 
    Asbtract ( 1414 )   PDF (419KB) ( 734 )  
    The effect of Ca,Mg and Pfertilization on the migration and accumulation of heavy metals in combined polluted soil and the response of crops to heavy metals are studied with field tests.The results show that on polluted soil, fertilization with Ca, Mg and Pcan restrain the migration and accumulation of heavy metals, especially Cd, Ph and As to and in crop grains.After fertilization, the adsorption amount of Cd by rice and wheat is decreased by 31.5-55 %.The amount of absorbed Ph in four crops is decreased by 23.4-57.8%, and that of Cu and Zn is slightly decreased.The absorbed As in rice is increased by 56.8%, and that in wheat and soybean is decreased by 61.8-81.1%.The existed forms of heavy metals in soils are changed, i.e., the percentage of exchangeable Cd, Ph and Zn is decreased, that of their carbonates is increased, and their available contents are declined.