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Table of Content

    25 May 2000, Volume 11 Issue 3
    Nutrient content in litterfall and its translocation in plantation forests in south China
    LI Zhian, LIN Yongbiao, PENG Shaolin
    2000, (3):  321-326. 
    Asbtract ( 0 )  
    The amounts of litterfall,nutrient content in it and leaves of five plantation forests in south China were determined.The order of litterfall biomass was in sequence of Acacia mangium (11.1t穐m-2)> Pinus elliotii (7.3t穐m-2)> Schima superba (6.5t穐m-2)> Acacia auriculaiformis (4.8t穐m-2)> Eucalyptus citriodora (2.6t穐m-2). A.mangium returned soil much more nutrient to soil through litterfall than other forests did.N,P and K were largely translocated from senescing leaves for all the five forests, and especially for A.mangium.Nutrient translocated varied greatly with seasons.The translocation of other elements was not definite.
    A comparative study on chlorophyll content, chlorophyll fluorescence and diurnal course of leaf gas exchange of two ecotypes of banyan
    ZHAO Ping, SUN Guchou, ZENG Xiaoping, PENG Shaolin, MO Ximu, LI Yuxiang
    2000, (3):  327-332. 
    Asbtract ( 0 )  
    The morphological differences,chlorophyll contents,fluorescence and diurnal course of leaf gas exchange between terrestrial banyan and amphibious banyan were compared with pot culture.The amphibious banyan possesses well developed aerial and hydro adventitious roots, and wider leaf with inclination of evolution toward mesophytic traits.The chlorophyll content of terrestrial banyan was higher than that of amphibious banyan.The diurnal course of leaf gas exchange indicated that net photosynthetic rate of terrestrial banyan was slightly higher than that of amphibious banyan grown in water,but much higher than that grown in soil.The amphibious banyan grown in water had the highest transpiration rate,the terrestrial banyan had a lower one, and the amphibious banyan grown in soil had the lowest.Linear regression analysis showed a positive correlation between net photosynthetic rate and stomatal conductance,implying that the stomatal conductance was dominant factor controlling the gas exchange.In this study,the term of intrinsic water use efficiency (net photosynthetic rate/stomatal conductance ratio,Intrinsic WUE) was applied to describe the photosynthesis and water properties, and the result showed that it was a more suitable measure compared to the usual WUE(net photosynthetic rate/transpiration rate).Among the three banyan plants examined,the amphibious banyan had the highest intrinsic WUE.
    Articles
    Life table analysis of Tsuga longibracteata population
    WU Chengzhen, HONG Wei, XIE Jinshou
    2000, 11(3):  333-336. 
    Asbtract ( 183 )   PDF (1KB) ( 124 )  
    Tsuga longibracteata is a rare and endangered tree species in China.Based on the life table of population and the theory of survival analysis,the authors worked out the life table of Tsuga longibracteata population drew the curves of mortality density function,hazard rate function and survival,and analyzed the population dynamics.The results show that the population had two peaks of mortality,and the survival curve of the population trended to the type of Deevey Ⅱ.
    Structure and spatial pattern dynamics of dominant populations in a natural forest in north Guangdong Province
    SU Zhiyao, WU Darong, CHEN Beiguang
    2000, 11(3):  337-341. 
    Asbtract ( 246 )  
    Five 1000-m2 plots were set up in a forest dominated by Schima superba, Castanopsis fargesii and Pinus massoniana in Luoba Nature Reserve, Shixing County, north Guangdong Province. Field data were obtained by tally with contiguous grid quadrat method. The analysis of population structure and spatial distribution patterns of the dominant species in the forest shows that S.superba and C.fargesii had a large reserve of seedlings, with up to 1538 and 9763 seedlings per hm2, respectively, showing a pyramid shape of population structure. Both populations had a high mortality for seedlings of classes Ⅰ and Ⅱ in the process of development to saplings. The population structure of P.massoniana was an inverse pyramid type, with no seedlings and only 4 saplings per hm2, but 44 large trees per hm2. The spatial distribution patterns of P.massoniana and C.fargesii in coniferous broadleaved mixed community chiefly dominated by broadleaved trees were uniform, and in those chiefly dominated by P.massoniana were aggregated, but there were different causes of pattern dynamics for P.massoniana and C.fargesii. S.superba in both communities showed an aggregated distribution pattern. The aggregation intensity was different, with K values from 0.4280 to 0.9750. Regarding the distribution patterns in different development stages, S.superba was aggregated in different stages, while C.fargesii varied with uniform distribution pattern for the large trees and aggregated distribution pattern for the saplings and median trees. As for P.massoniana, its median trees showed an aggregated distribution pattern, while both the saplings and large trees were uniform. The variations in spatial distribution patterns of populations in different development stages were closely related to the biological and ecological characteristics of the species, but different block size had an impact on the outcome of spatial distribution patterns.
    Molecular ecology of Cryptocarya chinensis populations in different communities
    WANG Zhengfeng, ZHANG Junli, WANG Bosun, LI Mingguang
    2000, (3):  342-344. 
    Asbtract ( 0 )  
    The amplified fragment length polymorphism (AFLP) method was used to analyze two populations of Cryptocarya chinensis, the succession climax species in lower subtropical broadleaved forest, The across two communities of evergreen broadleaved forest and mixed coniferous broadleaved forest. The analysis of molecular variance (AMOVA) indicated that the genetic variation was mostly due to the difference within individuals of the population (89.55%), with high significant genetic variation (10.45%) due to the different communities. The microenvironment of different communities and population biological characteristics resulted in the genetic divergence.
    Articles
    Evaluation on soil anti-erodibility of soil and water conservation forest
    SHEN Hui, JIANG Fengqi, DU Xiaojun, LU Tiange
    2000, 11(3):  345-348. 
    Asbtract ( 155 )   PDF (1KB) ( 58 )  
    Indexes including organic matter content, water stable aggregate content, mean weight diameter of water stable aggregate, aggregate degree and disperse coefficient were selected to evaluate soil anti-erodibility of soil and water conservation forests component of different tree species at different ages. The results showed that soil and water conservation forest played an important role in improving soil anti-erodibility, especially to the topsoil. Compared with that of Chinese pine pure forests, Chinese pine broadleaved mixed forests had higher soil organic matter content, and water stable aggregate content increased by 1.71%~38.53%, and soil anti-erodibility was also increased with increasing stand age.
    Ecological process of vegetation restoration in Caragana mirophylla sand-fixing area
    CAO Chengyou, JIANG Deming, Alamsa, LUO Yongming, KOU Zhenwu
    2000, 11(3):  349-354. 
    Asbtract ( 181 )  
    The occurrence and development of artificial vegetation after mobile sandy dunes being fixed by adopting straw check combining with seeding Caragana microphylla were studied. Especially the process of species invasion and the changes of community structure in 35 years were analyzed in detail. The results showed that the species richness of artificial community of C. microphylla increased, from 5 species (iN2 years) to 23 species in 35 years. In the structure concerning plant lifeform, therophytes were in dominant position, while the ratio of therophytes to all plant species had a tendency of decrease. The rates of species number and the quantity of hemicryptophytes and geocryptophytes increased gradually. Species diversity and community evenness indexes increased and ecological dominance index decreased gradually. The similarity index of the artificial plant community to natural one increased with age. The changes of physical and chemical property of soil were also discussed.
    A mechanistic model of phasic and phenological development of wheat I. Assumption and description of the model
    YAN Meichun, CAO Weixing, LUO Weihong, JIANG Haidong
    2000, 11(3):  355-359. 
    Asbtract ( 216 )  
    The temperature effectiveness for wheat development was non linearized and the apical and phenological development stages were systematically predicted by the scale of physiological development time which was based on the ecophysiological development process.The predicted apical development stages included single ridge stage,double ridge stage, floral initiation stage, stamen and pistil initiation stage,anther seperation stage,tetrad stage, and heading stage,while the predicted phenological development stages included germination stage, emergence stage,tillering stage, winterovering stage, green turning stage, jointing stage, booting stage, heading stage, flowering stage, grain filling stage,and maturity stage.Four cultivar specific parameters were used to describe the genotypic differences of wheat development.They were temperature sensitivity, physiological vernalization time, photoperiod sensitivity, and intrinsic earliness, reflecting the genetic properties of different cultivars in thermal effectiveness, vernalization, photoperiod response and shortest time required for reaching flowering, respectively.The four parameters determined the physiological development time required for each development stage of different cultivars.
    Articles
    Dynamics of soil P pool in a long-term fertilizing experiment of wheat-maize rotation Ⅰ. Crop yield effect of fertilizer P and dynamics of soil total P and inorganic P
    LIU Jianling, ZHANG Fusuo
    2000, 11(3):  360-364. 
    Asbtract ( 159 )  
    The effects of long-term applying fertilizer P and manure on the pools of soil total P and inorganic P and the crop yield in rotation of winter wheat-summer maize→spring maize were studied. The results showed that the pool of soil total P and inorganic P were increased by applying fertilizer P and manure, and the phosphorus mostly accumulated in soil was inorganic P. The critical amounts of fertilizer P (P2O5) for balancing soil P were 94.7 kg·hm-2 to winter wheat-summer maize and 51.5 kg·hm-2 to spring maize. Based on regression equations, the application rates of fertilizer P (P2O5) for economic optimum and highest yields were 135.8 and 149.8 kg·hm-2 to winter wheat-summer maize, and 88.6 and 95.9 kg·hm-2 to spring maize, respectively.
    Dynamics of soil P pool in a long-term fertilizing experiment of wheat-maize rotation Ⅱ. Dynamics of soil Olsen-P and inorganic P
    LIU Jianling, ZHANG Fusuo
    2000, 11(3):  365-368. 
    Asbtract ( 177 )  
    Studies on the dynamics of soil Olsen-P and different form inorganic P in the long-term fertilizing experiment of winter wheat-summer maize→spring maize rotation showed that the contents of Olsen-P and inorganic P were changed by the accumulation and consumption of P in soil. In P0 treatments, Olsen-P decreased gradually, and then, trended to the critical level. When fertilizing amount was basically equal to the intake by crops, the balance of Olsen-P was dynamically maintained. The contents of Olsen-P and inorganic P were enhanced, when applied P was larger than the P intake by crops. The major contents of residual inorganic P were Ca2-P and Ca8-P, both accounting for 52.3% of total inorganic P in average, and Ca8-P accounting for 78.3%. Al P and Fe P accounted for 26.1%, and O-P and Ca10-P accounted for 20.4% of total inorganic P.The availability of fertilizer P was obviously increased by long-term applying fertilizer P together with manure, compared with applying fertilizer P alone.
    Two-phase linear models of leaf emergence at different tillering positions in wheat and effects of different varieties and sowing dates
    CAO Weixing, LI Cundong, YAN Meichun, ZOU Wei
    2000, (3):  369-372. 
    Asbtract ( 0 )  
    Dynamics of leaf emergence shows the development progress and its relationship with growth in wheat. It was found that two phase linear model equations (phase Ⅰ faster than phase Ⅱ) divided by glum differentiation stage could describe leaf emergence progress in relation to growing degree days (GDD) after sowing in wheat. This pattern was consistent in main stems and tillers of normal development with both winter and spring type varieties. The beginning of phase Ⅱ shifted to an earlier development stage on main stems of winter type varieties of early planting (EP, September 30) and late planting (LP, March 2), and on T3 of both varieties of EP, MP (middle planting, on October 30) and LP due to their abnormal development. The thermal rate of leaf emergence on main stem was relatively high and steady during development for winter type variety of MP, and quickened with the postponing of sowing for spring type variety. The above results illustrated the difference of leaf emergence at different tillering positions, and the biological characteristics affected by different varieties and sowing dates.
    Nutrition of wheat under wet injury and its regulation
    CHANG Jiang
    2000, (3):  373-376. 
    Asbtract ( 0 )  
    With pot experiment,this paper dealt with the effects of different nutrition regulations on nutrient absorption and crop yield of wheat under waterlogged condition. N,P,K,Zn,Cu uptakes by wheat were greatly inhibited by waterlogging.The total amounts of reusable elements N,P,K and Zn in leaves decreased obviously in stems but did not in ears, compared with control;while the total amount of element Cu in all parts was reduced by waterlogging.The yield of individual wheat plant was significantly reduced under waterlogging.Additional N-fertilizer or spraying N,P and K significantly increased the uptake of nutrients and the yield for Wanmai 19 under light waterlogging,but were not effective for Yanmai 158 under heavy waterlogging.A positive correlation was found between the yield of wheat under waterlogging and the N accumulation in leaves.
    Articles
    Effects of soil moisture and shading levels on photosynthetic characteristics of cotton leaves
    LIU Xianzhso, KANG Shaozhong, SHAO Mingan, WANG Li
    2000, 11(3):  377-381. 
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    The effects of different soil moistures and shading levels on stomatal conductance(Gs),net photosynthetic rates(Pn),transpiration and leaf water potential (LWP) of cotton (variety Zhongmian No.23) grown in pots from the seedling to flower bud stages in summer noon were evaluated.We designed three shading levels:no-shading(CK),75% shading (DN), 40% shading(SN);and three soil moistures:85~100%(high water,HW),65%~85% (mediun water,MW)and 45%~65%(low water,LW)of field water-bolding capacity.The Gs of DN and SN increased by 16.69% and 28.01% compared with CK at HW,respectively,while the Pn of DN and SN declined by 45.74% and 20.54%,respectively.The G5 of DN and SN enhanced by 28.86% and 23.28% compareds with CK at MW,respectively,while the Pn of DN and SN decreased by 31.97% and 1.64%,respectively.The Gs of CK,DN and SN did not exhibit significant differences at LW,while Pn of DN and SN reduced by 46.22% and 13.45%,respectively.Significant difference in Gs did not exist between DN and SN at the same soil moisture,but there was significant differnece in Pn between them (except at LW).It was suggested that Gs declined with the increasing of leaf-to-air vapor pressure difference(VPD) and showed weak correlation with Pn by regression.The combined effects of soil moistures and shading levels on LWP and transpiration rate were not significant.There was no significant difference in LWP and transpiration rate among three shading treatments.Contrasted to treatment CK,intercellular CO2 concentration (Ci) in DN and SN at HW,MW and LW increased significantly,except no arrarent change of Ci in SN at MW.
    Effect of lanthanum on growth and biochemical property of Sclerotinia sclerotiorum
    ZHANG Jian, CHENG Heyuan, GAO Qian, ZHANG Zili, LIU Qingdu
    2000, 11(3):  382-384. 
    Asbtract ( 138 )  
    The study shows that La2O3 at a concentration of 30~450mg·L-1 could inhibit the growth of S.sclerotiorum in both solid and liquid media and the inhibition effect was increased with its increasing concentration.The activity of pectinase produced by S.sclerotiorum in liquid mediumwas was also increased with increasing La2O3 concentration.
    Articles
    CO2 release from typical Stipa grandis grassland soil
    CUI Xiaoyong, CHEN Siqing, CHEN Zuozhong
    2000, 11(3):  390-394. 
    Asbtract ( 160 )  
    Determinations on the soil respiration in a typical Stipa grandis grassland of Inner Mongolica by the method of static chamber/alkaline absorbing show that there existed great spatial and temporal variances of soil respiration,and the factors controlling these variances were different.The seasonal variance of soil respiration had a close relationship with the aboveground biomass of S.grandis and the status of soil moisture.The total amount of annual CO2 release in 1995,1997 and 1998 was estimated as 180,45.8 and 225 gC·m-2 ·yr-1, respectively.Overgrazing greatly decreased the biomass of the community,and also, decreased the CO2 release from the soil.The possibility of establishing a dynamic model of soil respiration in grassland with precipitation as a driven factor was discussed.
    Behavior response of four Leis axyridis varieties to volatiles from tea and Toxoptera aurantii
    HAN Baoyu, CHEN Zongmao
    2000, 11(3):  413-416. 
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    The behavior response of the adults of four Leis axyridis varieties to kairomone from Toxoptera aurantii was determined by Y shape olfaction instrument. The results showed that when supplied with two-two-combinations of Toxoptera aurantii,Brevicoryne brassicae and Lipaphis erysimi, tea aphids plus aphid-damaged vs. normal shoots,and aphid-damaged vs. normal shoots, Leis axyridis had a preference for tea aphids,tea aphids plus aphid-damaged tea shoots,or aphid-damaged tea shoots.There existed a Logistic curve relationship(P<0.01) between odor source tendency rate of Leis axyridis and odor source quality, when 8~9 kinds of odor gradients including tea aphids plus aphid-damaged tea shoots,aphid-damaged tea shoots and tea aphids were used as odor sources.The tendency rates of Leis axyridis ab. bimaculata,Leis axyridis ab. conspicua and Leis axyridis var. novemdecimpunctata showed single left tilting peak curves to the aphid number(P<0.01).Ether and n hexane ringes of Toxoptera aurantii body surface also showed an attraction to all varieties. Leis axyridis var. spectabilis was the most sensitive variety.
    Articles
    Grey system analysis on dominant natural enemies influencing Aphis gosspyii population
    BI Shoudong, ZOU Yunding, CHEN Gaochao, MENG Qinglei, WANG Gongming
    2000, 11(3):  417-420. 
    Asbtract ( 146 )  
    The populations of Aphis gosspyii and its natural enemies before cotton boll stage were investigated systematically in 1983, 1984, 1986, 1988, 1994 and 1995. The relationship between daily total predation of natural enemies and Aphis gosspyii population size was studied with the grey system theory and method, and the relational grade of various natural enemies to ideal superior natural enemies was analyzed. The results show that Propylaca japonica was the major natural enemy influencing Aphis gossypii, followed by Chrysopa septempunctata, then by Therdion octomaculatum and Erigonidium graminicola.
    Nutrient content in litterfall and its translocation in plantation forests in south China
    LI Zhian, LIN Yongbiao, PENG Shaolin
    2000, (3):  321-326. 
    Asbtract ( 1137 )   PDF (739KB) ( 261 )  
    The amounts of litterfall,nutrient content in it and leaves of five plantation forests in south China were determined.The order of litterfall biomass was in sequence of Acacia mangium (11.1t穐m-2)> Pinus elliotii (7.3t穐m-2)> Schima superba (6.5t穐m-2)> Acacia auriculaiformis (4.8t穐m-2)> Eucalyptus citriodora (2.6t穐m-2). A.mangium returned soil much more nutrient to soil through litterfall than other forests did.N,P and K were largely translocated from senescing leaves for all the five forests, and especially for A.mangium.Nutrient translocated varied greatly with seasons.The translocation of other elements was not definite.
    A comparative study on chlorophyll content, chlorophyll fluorescence and diurnal course of leaf gas exchange of two ecotypes of banyan
    ZHAO Ping, SUN Guchou, ZENG Xiaoping, PENG Shaolin, MO Ximu, LI Yuxiang
    2000, (3):  327-332. 
    Asbtract ( 1122 )   PDF (890KB) ( 272 )  
    The morphological differences,chlorophyll contents,fluorescence and diurnal course of leaf gas exchange between terrestrial banyan and amphibious banyan were compared with pot culture.The amphibious banyan possesses well developed aerial and hydro adventitious roots, and wider leaf with inclination of evolution toward mesophytic traits.The chlorophyll content of terrestrial banyan was higher than that of amphibious banyan.The diurnal course of leaf gas exchange indicated that net photosynthetic rate of terrestrial banyan was slightly higher than that of amphibious banyan grown in water,but much higher than that grown in soil.The amphibious banyan grown in water had the highest transpiration rate,the terrestrial banyan had a lower one, and the amphibious banyan grown in soil had the lowest.Linear regression analysis showed a positive correlation between net photosynthetic rate and stomatal conductance,implying that the stomatal conductance was dominant factor controlling the gas exchange.In this study,the term of intrinsic water use efficiency (net photosynthetic rate/stomatal conductance ratio,Intrinsic WUE) was applied to describe the photosynthesis and water properties, and the result showed that it was a more suitable measure compared to the usual WUE(net photosynthetic rate/transpiration rate).Among the three banyan plants examined,the amphibious banyan had the highest intrinsic WUE.
    Articles
    Life table analysis of Tsuga longibracteata population
    WU Chengzhen, HONG Wei, XIE Jinshou
    2000, (3):  333-336. 
    Asbtract ( 1468 )   PDF (227KB) ( 458 )  
    Tsuga longibracteata is a rare and endangered tree species in China.Based on the life table of population and the theory of survival analysis,the authors worked out the life table of Tsuga longibracteata population drew the curves of mortality density function,hazard rate function and survival,and analyzed the population dynamics.The results show that the population had two peaks of mortality,and the survival curve of the population trended to the type of Deevey Ⅱ.
    Structure and spatial pattern dynamics of dominant populations in a natural forest in north Guangdong Province
    SU Zhiyao, WU Darong, CHEN Beiguang
    2000, (3):  337-341. 
    Asbtract ( 1392 )   PDF (811KB) ( 678 )  
    Five 1000-m2 plots were set up in a forest dominated by Schima superba, Castanopsis fargesii and Pinus massoniana in Luoba Nature Reserve, Shixing County, north Guangdong Province. Field data were obtained by tally with contiguous grid quadrat method. The analysis of population structure and spatial distribution patterns of the dominant species in the forest shows that S.superba and C.fargesii had a large reserve of seedlings, with up to 1538 and 9763 seedlings per hm2, respectively, showing a pyramid shape of population structure. Both populations had a high mortality for seedlings of classes Ⅰ and Ⅱ in the process of development to saplings. The population structure of P.massoniana was an inverse pyramid type, with no seedlings and only 4 saplings per hm2, but 44 large trees per hm2. The spatial distribution patterns of P.massoniana and C.fargesii in coniferous broadleaved mixed community chiefly dominated by broadleaved trees were uniform, and in those chiefly dominated by P.massoniana were aggregated, but there were different causes of pattern dynamics for P.massoniana and C.fargesii. S.superba in both communities showed an aggregated distribution pattern. The aggregation intensity was different, with K values from 0.4280 to 0.9750. Regarding the distribution patterns in different development stages, S.superba was aggregated in different stages, while C.fargesii varied with uniform distribution pattern for the large trees and aggregated distribution pattern for the saplings and median trees. As for P.massoniana, its median trees showed an aggregated distribution pattern, while both the saplings and large trees were uniform. The variations in spatial distribution patterns of populations in different development stages were closely related to the biological and ecological characteristics of the species, but different block size had an impact on the outcome of spatial distribution patterns.
    Molecular ecology of Cryptocarya chinensis populations in different communities
    WANG Zhengfeng, ZHANG Junli, WANG Bosun, LI Mingguang
    2000, (3):  342-344. 
    Asbtract ( 985 )   PDF (194KB) ( 241 )  
    The amplified fragment length polymorphism (AFLP) method was used to analyze two populations of Cryptocarya chinensis, the succession climax species in lower subtropical broadleaved forest, The across two communities of evergreen broadleaved forest and mixed coniferous broadleaved forest. The analysis of molecular variance (AMOVA) indicated that the genetic variation was mostly due to the difference within individuals of the population (89.55%), with high significant genetic variation (10.45%) due to the different communities. The microenvironment of different communities and population biological characteristics resulted in the genetic divergence.
    Articles
    Evaluation on soil anti-erodibility of soil and water conservation forest
    SHEN Hui, JIANG Fengqi, DU Xiaojun, LU Tiange
    2000, (3):  345-348. 
    Asbtract ( 1330 )   PDF (583KB) ( 406 )  
    Indexes including organic matter content, water stable aggregate content, mean weight diameter of water stable aggregate, aggregate degree and disperse coefficient were selected to evaluate soil anti-erodibility of soil and water conservation forests component of different tree species at different ages. The results showed that soil and water conservation forest played an important role in improving soil anti-erodibility, especially to the topsoil. Compared with that of Chinese pine pure forests, Chinese pine broadleaved mixed forests had higher soil organic matter content, and water stable aggregate content increased by 1.71%~38.53%, and soil anti-erodibility was also increased with increasing stand age.
    Ecological process of vegetation restoration in Caragana mirophylla sand-fixing area
    CAO Chengyou, JIANG Deming, Alamsa, LUO Yongming, KOU Zhenwu
    2000, (3):  349-354. 
    Asbtract ( 1288 )   PDF (1097KB) ( 209 )  
    The occurrence and development of artificial vegetation after mobile sandy dunes being fixed by adopting straw check combining with seeding Caragana microphylla were studied. Especially the process of species invasion and the changes of community structure in 35 years were analyzed in detail. The results showed that the species richness of artificial community of C. microphylla increased, from 5 species (iN2 years) to 23 species in 35 years. In the structure concerning plant lifeform, therophytes were in dominant position, while the ratio of therophytes to all plant species had a tendency of decrease. The rates of species number and the quantity of hemicryptophytes and geocryptophytes increased gradually. Species diversity and community evenness indexes increased and ecological dominance index decreased gradually. The similarity index of the artificial plant community to natural one increased with age. The changes of physical and chemical property of soil were also discussed.
    A mechanistic model of phasic and phenological development of wheat I. Assumption and description of the model
    YAN Meichun, CAO Weixing, LUO Weihong, JIANG Haidong
    2000, (3):  355-359. 
    Asbtract ( 1674 )   PDF (630KB) ( 491 )  
    The temperature effectiveness for wheat development was non linearized and the apical and phenological development stages were systematically predicted by the scale of physiological development time which was based on the ecophysiological development process.The predicted apical development stages included single ridge stage,double ridge stage, floral initiation stage, stamen and pistil initiation stage,anther seperation stage,tetrad stage, and heading stage,while the predicted phenological development stages included germination stage, emergence stage,tillering stage, winterovering stage, green turning stage, jointing stage, booting stage, heading stage, flowering stage, grain filling stage,and maturity stage.Four cultivar specific parameters were used to describe the genotypic differences of wheat development.They were temperature sensitivity, physiological vernalization time, photoperiod sensitivity, and intrinsic earliness, reflecting the genetic properties of different cultivars in thermal effectiveness, vernalization, photoperiod response and shortest time required for reaching flowering, respectively.The four parameters determined the physiological development time required for each development stage of different cultivars.
    Articles
    Dynamics of soil P pool in a long-term fertilizing experiment of wheat-maize rotation Ⅰ. Crop yield effect of fertilizer P and dynamics of soil total P and inorganic P
    LIU Jianling, ZHANG Fusuo
    2000, (3):  360-364. 
    Asbtract ( 1316 )   PDF (1002KB) ( 363 )  
    The effects of long-term applying fertilizer P and manure on the pools of soil total P and inorganic P and the crop yield in rotation of winter wheat-summer maize→spring maize were studied. The results showed that the pool of soil total P and inorganic P were increased by applying fertilizer P and manure, and the phosphorus mostly accumulated in soil was inorganic P. The critical amounts of fertilizer P (P2O5) for balancing soil P were 94.7 kg·hm-2 to winter wheat-summer maize and 51.5 kg·hm-2 to spring maize. Based on regression equations, the application rates of fertilizer P (P2O5) for economic optimum and highest yields were 135.8 and 149.8 kg·hm-2 to winter wheat-summer maize, and 88.6 and 95.9 kg·hm-2 to spring maize, respectively.
    Dynamics of soil P pool in a long-term fertilizing experiment of wheat-maize rotation Ⅱ. Dynamics of soil Olsen-P and inorganic P
    LIU Jianling, ZHANG Fusuo
    2000, (3):  365-368. 
    Asbtract ( 1400 )   PDF (539KB) ( 261 )  
    Studies on the dynamics of soil Olsen-P and different form inorganic P in the long-term fertilizing experiment of winter wheat-summer maize→spring maize rotation showed that the contents of Olsen-P and inorganic P were changed by the accumulation and consumption of P in soil. In P0 treatments, Olsen-P decreased gradually, and then, trended to the critical level. When fertilizing amount was basically equal to the intake by crops, the balance of Olsen-P was dynamically maintained. The contents of Olsen-P and inorganic P were enhanced, when applied P was larger than the P intake by crops. The major contents of residual inorganic P were Ca2-P and Ca8-P, both accounting for 52.3% of total inorganic P in average, and Ca8-P accounting for 78.3%. Al P and Fe P accounted for 26.1%, and O-P and Ca10-P accounted for 20.4% of total inorganic P.The availability of fertilizer P was obviously increased by long-term applying fertilizer P together with manure, compared with applying fertilizer P alone.
    Two-phase linear models of leaf emergence at different tillering positions in wheat and effects of different varieties and sowing dates
    CAO Weixing, LI Cundong, YAN Meichun, ZOU Wei
    2000, (3):  369-372. 
    Asbtract ( 949 )   PDF (273KB) ( 223 )  
    Dynamics of leaf emergence shows the development progress and its relationship with growth in wheat. It was found that two phase linear model equations (phase Ⅰ faster than phase Ⅱ) divided by glum differentiation stage could describe leaf emergence progress in relation to growing degree days (GDD) after sowing in wheat. This pattern was consistent in main stems and tillers of normal development with both winter and spring type varieties. The beginning of phase Ⅱ shifted to an earlier development stage on main stems of winter type varieties of early planting (EP, September 30) and late planting (LP, March 2), and on T3 of both varieties of EP, MP (middle planting, on October 30) and LP due to their abnormal development. The thermal rate of leaf emergence on main stem was relatively high and steady during development for winter type variety of MP, and quickened with the postponing of sowing for spring type variety. The above results illustrated the difference of leaf emergence at different tillering positions, and the biological characteristics affected by different varieties and sowing dates.
    Nutrition of wheat under wet injury and its regulation
    CHANG Jiang
    2000, (3):  373-376. 
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    With pot experiment,this paper dealt with the effects of different nutrition regulations on nutrient absorption and crop yield of wheat under waterlogged condition. N,P,K,Zn,Cu uptakes by wheat were greatly inhibited by waterlogging.The total amounts of reusable elements N,P,K and Zn in leaves decreased obviously in stems but did not in ears, compared with control;while the total amount of element Cu in all parts was reduced by waterlogging.The yield of individual wheat plant was significantly reduced under waterlogging.Additional N-fertilizer or spraying N,P and K significantly increased the uptake of nutrients and the yield for Wanmai 19 under light waterlogging,but were not effective for Yanmai 158 under heavy waterlogging.A positive correlation was found between the yield of wheat under waterlogging and the N accumulation in leaves.
    Articles
    Effects of soil moisture and shading levels on photosynthetic characteristics of cotton leaves
    LIU Xianzhso, KANG Shaozhong, SHAO Mingan, WANG Li
    2000, (3):  377-381. 
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    The effects of different soil moistures and shading levels on stomatal conductance(Gs),net photosynthetic rates(Pn),transpiration and leaf water potential (LWP) of cotton (variety Zhongmian No.23) grown in pots from the seedling to flower bud stages in summer noon were evaluated.We designed three shading levels:no-shading(CK),75% shading (DN), 40% shading(SN);and three soil moistures:85~100%(high water,HW),65%~85% (mediun water,MW)and 45%~65%(low water,LW)of field water-bolding capacity.The Gs of DN and SN increased by 16.69% and 28.01% compared with CK at HW,respectively,while the Pn of DN and SN declined by 45.74% and 20.54%,respectively.The G5 of DN and SN enhanced by 28.86% and 23.28% compareds with CK at MW,respectively,while the Pn of DN and SN decreased by 31.97% and 1.64%,respectively.The Gs of CK,DN and SN did not exhibit significant differences at LW,while Pn of DN and SN reduced by 46.22% and 13.45%,respectively.Significant difference in Gs did not exist between DN and SN at the same soil moisture,but there was significant differnece in Pn between them (except at LW).It was suggested that Gs declined with the increasing of leaf-to-air vapor pressure difference(VPD) and showed weak correlation with Pn by regression.The combined effects of soil moistures and shading levels on LWP and transpiration rate were not significant.There was no significant difference in LWP and transpiration rate among three shading treatments.Contrasted to treatment CK,intercellular CO2 concentration (Ci) in DN and SN at HW,MW and LW increased significantly,except no arrarent change of Ci in SN at MW.
    Effect of lanthanum on growth and biochemical property of Sclerotinia sclerotiorum
    ZHANG Jian, CHENG Heyuan, GAO Qian, ZHANG Zili, LIU Qingdu
    2000, (3):  382-384. 
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    The study shows that La2O3 at a concentration of 30~450mg·L-1 could inhibit the growth of S.sclerotiorum in both solid and liquid media and the inhibition effect was increased with its increasing concentration.The activity of pectinase produced by S.sclerotiorum in liquid mediumwas was also increased with increasing La2O3 concentration.
    Production and reduction of nitrous oxide in agricultural and forest soils
    YU Kewei, CHEN Guanxiong, StenStruwe, Annelise KjФller
    2000, (3):  385-389. 
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    A soil water slurry experiment was conducted to study the potentials of N2O production and reduction in denitrification of agricultural and beech forest soils in Denmark. The effects of nitrate and ammonium additions on denitrification were also investigated. The forest soil showed a higher denitrification potential than the agricultural soil. However, N2O reduction potential of the agricultural soil was higher than the beech forest soil, shown by the ratio of N2O/N2 approximately 0.11 and 3.65 in the agricultural and the beech forest soils, respectively. Both nitrate and ammonium additions stimulated the N2O production in the two soils, but reduced the N2O reduction rates in the agricultural soil slurries. In contrast to the effect on the agricultural soil, nitrate reduced the N2O reduction rate in the beech forest soil, while ammonium showed a stimulating effect on the N2O reduction activity. After one week incubation, all of the N2O produced was reduced to N2 in the agricultural soil when nitrate was still present. Nitrous oxide reduction in the beech forest soil occurred only when nitrate almost disappeared. The different nitrate inhibitory effect on the N2O reduction activity in the two soils was due to the difference in soil pH. Inhibition of nitrate on N2O reduction was significant under acidic condition. Consequently, soil could serve as a sink of atmospheric N2O under the conditions of anaerobic, pH near neutral and low nitrate content.
    Articles
    CO2 release from typical Stipa grandis grassland soil
    CUI Xiaoyong, CHEN Siqing, CHEN Zuozhong
    2000, (3):  390-394. 
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    Determinations on the soil respiration in a typical Stipa grandis grassland of Inner Mongolica by the method of static chamber/alkaline absorbing show that there existed great spatial and temporal variances of soil respiration,and the factors controlling these variances were different.The seasonal variance of soil respiration had a close relationship with the aboveground biomass of S.grandis and the status of soil moisture.The total amount of annual CO2 release in 1995,1997 and 1998 was estimated as 180,45.8 and 225 gC穖-2 穣r-1, respectively.Overgrazing greatly decreased the biomass of the community,and also, decreased the CO2 release from the soil.The possibility of establishing a dynamic model of soil respiration in grassland with precipitation as a driven factor was discussed.
    Influence of plant species diversity on productivity of sandy grassland in Kerqin Region
    CHANG Xueli, ZHAO Halin, YANG Chi, XU Jie
    2000, (3):  395-398. 
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    The relationship between species diversity indices and sandy grassland productivity was studied in Kerqin sandy land, and the results showed that the relations could be divided in to two categories based on the indices and productivity.The first type includes function and composition diversities, their maximal biomass varied form 299 to 336g穖-2, and had a simple linear relation with the productivity. Their correlation coefficient was remarkably significant.The species richness and Shannon-Wiener indices attribute to second type, their maximal biomass varied from 426 to 433 g穖-2, and had a complex parabola relations with the productivity. Their correlation coefficient was also significant.Meanwhile,the grey correlation analysis showed that the species composition diversity index was the most important factor that influences productivity.According to the grey correlation degree, the order of the different indices affecting productivity was:composition diversity(0.74),function diversity (0.72),species richness (0.66) and Shannon-Wiener index (0.14).It is suggested that increasing plant species richness (species introduction) and consequent composition diversity could be the practices of improving the degraded grassland in Kerqin.
    Effect of grazing on reproduction in Leymus chinensis population
    WANG Renzhong
    2000, (3):  399-402. 
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    The experiment on the effect of grazing on the asexual and sexual reproduction and biomass allocation in Leymus chinensis population was conducted in Songnen grassland. The results show that animal grazing reduced both asexual and sexual reproductive channels.With the increase of grazing intensity,the densities of asexual shoots and rhizome tillers, seed biomass, numbers of seeds per inflorescence and sexual shoot ratio decreased significantly,especially after heavy grazing.The rates of biomass allocation to rhizome increased significantly with increasing grazing intensity, while the rates of biomass allocation to assimilation, unassimilation organs and seed production decreased remarkably.In the haviest grazing stage,there were almost no sexual shoots.
    Age structure of tillers of Hordeum brevisulatum clone in Songnen plain of China
    LI Hong, YANG Yunfei, QIAO Xibo
    2000, (3):  403-407. 
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    The tillers of Hordeum brevisulatum clone have a significantly expanding age structure, which includes three age classes. The 1st age class tillers are absolutely dominant in the reproductive growth of the clone. The older the tillers, the smaller the rate of quantitative increase, and the less the accumulative nutrients are. The quantity and biomass of the 1st and 2nd age classes increase with the size and the tiller number of the clone, while the 3rd age class tillers are positively linearly interrelated to the total tillers of the clone. The mean weight per tiller decreases with the age class increased. The mean weight per reproductive tiller is relatively constant among three age classes, and that of the 1st tillers of clone has a negative respondence to the density of tiller. The age structure of the potential population of clone is also of an obviously expanding type. The buds on the vegetative tillers are always more than those on the reproductive tillers. The buds on the vegetative or reproductive tillers of every age class are all positively interrelated to the size and the total tillers of clone.
    β-diversity of Stipa communities in Inner Mongolia Plateau
    BAI Yongfei, XING Xuerong, XU Zhixin, LI Dexin
    2000, (3):  408-412. 
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    The β-diversity characteristics of four Stipa communities (S.baicalensis, S.grandis, S.krylovii and S.klemenzii) were studied using comparable plots methods. As a measurement of species turnover within communities, Whittacker's index(βws) was size dependent, and reduced gradually with the increasing quadrat size.Under the same scale,βws indices of the communities were similar.Cody's index (βc)was also affected by sampling size.βc increased initially as quadrat size enlarged,then stabilized over the size of 0.5m2 for S.baicalensis and S.grandis communities, and 2 m2 for S. krylovii and S.klemenzii communities. S.baicalensis community had the highest Cody index, while S.klemenzii community had the lowest one. In most cases, the within community distance interval had a relatively high effect on Cody index; From S.baicalensis to S.klemenzii community,the functional group diversities of forbs,perennial bunch and rhizome grasses decreased greatly,the diversity of intermediate xerads reduced significantly,and the diversity of xerads increased firstly, and then declined for S.klemenzii community.The changes in species composition of four Stipa communities could give a reflection to the degrees of community replacement along ecological gradients,and Cody indices between the communities reduced gradually.The Morisita Horn similarity coefficient between S.baicalensis and S.grandis community was significantly higher (0.72) than those between S.grandis and S.krylovii communities (0.55),and between S.krylovii and S.klemenzii communities(0.42).
    Behavior response of four Leis axyridis varieties to volatiles from tea and Toxoptera aurantii
    HAN Baoyu, CHEN Zongmao
    2000, (3):  413-416. 
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    The behavior response of the adults of four Leis axyridis varieties to kairomone from Toxoptera aurantii was determined by Y shape olfaction instrument. The results showed that when supplied with two-two-combinations of Toxoptera aurantii,Brevicoryne brassicae and Lipaphis erysimi, tea aphids plus aphid-damaged vs. normal shoots,and aphid-damaged vs. normal shoots, Leis axyridis had a preference for tea aphids,tea aphids plus aphid-damaged tea shoots,or aphid-damaged tea shoots.There existed a Logistic curve relationship(P<0.01) between odor source tendency rate of Leis axyridis and odor source quality, when 8~9 kinds of odor gradients including tea aphids plus aphid-damaged tea shoots,aphid-damaged tea shoots and tea aphids were used as odor sources.The tendency rates of Leis axyridis ab. bimaculata,Leis axyridis ab. conspicua and Leis axyridis var. novemdecimpunctata showed single left tilting peak curves to the aphid number(P<0.01).Ether and n hexane ringes of Toxoptera aurantii body surface also showed an attraction to all varieties. Leis axyridis var. spectabilis was the most sensitive variety.
    Articles
    Grey system analysis on dominant natural enemies influencing Aphis gosspyii population
    BI Shoudong, ZOU Yunding, CHEN Gaochao, MENG Qinglei, WANG Gongming
    2000, (3):  417-420. 
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    The populations of Aphis gosspyii and its natural enemies before cotton boll stage were investigated systematically in 1983, 1984, 1986, 1988, 1994 and 1995. The relationship between daily total predation of natural enemies and Aphis gosspyii population size was studied with the grey system theory and method, and the relational grade of various natural enemies to ideal superior natural enemies was analyzed. The results show that Propylaca japonica was the major natural enemy influencing Aphis gossypii, followed by Chrysopa septempunctata, then by Therdion octomaculatum and Erigonidium graminicola.
    Geostatistical analysis on spatial patterns of Aphis gossypii and Propylaca japonica
    BI Shoudong, ZOU Yunding, GENG Jiguang, WANG Gongming, CHEN Gaochao, MENG Qinglei
    2000, (3):  421-424. 
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    The spatial construction and distribution of Aphis gossypii and Propylaca japonica at different period were investigated with geostatistics.The results showed that the semivariogram of Aphis gossypii was described by spherical model,indicating an aggregated spatial arrangement,the range was 8.21~10.81m.The semivariograms of Propylaca japonica was fitted by spherical model too,also indicating an aggregated spatial arrangement,its range was 8.01~14.25m.The amount and spatial distribution of Propylaca japonica was closely related to that of Aphis gossypii. It reveals that Propylaca japonica is dominant natural enemies of influening population of Ahphis gossypii.
    Effect of plumular axis-cutted cotton on growth and development of cotton bollworm
    LI Ping, ZHANG Qingwen, CAI Qingnian
    2000, (3):  425-427. 
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    The method of plumular axis cutting was used to induce the resistance of cotton plants to cotton bollworms(Heliothis armigera). The bollworm was cultured in the laboratory, and the effect of induced cotton on the duration of larval development and weights of larvae and pupae was studied.In the treatments of infection and control,the lengths of larval period were delayed by 3 days and 0.5 days,the weights of larvae were decreased by 19.60% and 11.45%,and the pupae weights were decreased by 10.81% and 6.54%,respectively.After the 8 days old larvae were reared with induced cotton leaves for 3 days,the infected and uninfected cutted plants resulted in a decrease of the relative growth rates of larvae by 22.9% and 17.2% respectively,and in a decrease of the relative feeding rates by 26.1% and 21.4% respectively.It is suggested that plumular axis cutting could induce the resistance of cotton plants to bollworm,and influence the growth and development speed of bollworms through retarding their feeding and digestion.Combining with the treatment of Pseudomona gladioli D-2251 strain could obviously increase the insect resistance of cotton plants.
    Community characteristics of soil ciliated protozoan at Dapeng Peninsula
    XU Runlin, SUN Yixiang
    2000, (3):  428-430. 
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    With the qualitative and quantitative analysis, the community characteristics of soil ciliated protozoan sample from Dapeng Peninsula,Guangdong province was studied.The comunity consisted of 42 species of ciliates, including 4 new records in China.The major species were Cohnilembus vexillarius,Colpoda henneguy,Clopoda steinii,Histriculus muscorum,Gonostomum affine,Drepanomonas revolata,Leptopharynx costatus and Dileptus alpinus. Culturing the ciliated protozoan in laboratory showed that the species succession of domimant speies during the culture was from Gonostomum affine and Histriculus muscorum n the early stage to Cohnilembus vexillaria, and then to Colpoda spp.The difference of soil cliated communities between in Dapeng Peninsula and other regions was compared,and the possible factors affecting the difference were analyzed.
    Effect of rhizospheric environment of VA-mycorrhizal plants on forms of Cu,Zn,Pb and Cd in polluted soil
    HUANG Yi, CHEN Youjian, TAO Shu
    2000, (3):  431-434. 
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    Maize (Zea mays L.) was inoculated with or without VA-mycorrhizal (Glomus mosseae) and cultivated in a heavy metals contaminated soil. The distribution and dynamics of Cu,Zn,Pb and Cd forms in rhizosphere of maize inoculated with or without VA-mycorrhizal were analyzed with the technique of sequential extraction. Comparing with control soil, exchangeable Cu in rhizospheric soil increased significantly, and the exchangeable Cd trended down. In rhizosphere of VA-mycorrhizal maize, the amounts of Cu, Zn and Pb bound to organic matter were significantly higher than those in rhizosphere of non-mycorrhizal maize, while the four tested metals bound to carbonates and to iron and manganese oxides were constant in rhizosphere of mycorrhizal and non-mycorrhizal maize. These results illustrated that the plant roots could influence the distribution and dynamics of metal forms in rhizosphere, and much for mycorrhizal plants than for non-mycorrhizal plants. At excessive concentration of soil metals, mycorrhizal roots might decrease the bio availability of toxic heavy metals by changing their forms. The factors that caused the change of metal fractions in rhizosphere of mycorrhizal and non-mycorrhizal plants were also discussed.
    A preliminary approach on mass-balance ecopath model of the Bohai Sea
    TONG Ling, TANG Qisheng, DanielPauly
    2000, (3):  435-440. 
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    A Bohai Sea mass-balance ecopath model is constructed on the basis of fisheries resources data from the ecosystem survey conducted from April 1982 to May 1983. It is the first ecopath model which consists of 13 function groups (boxes), and only covers the main trophic flow in the Bohai Sea ecosystem. P/B and Q/B parameters (P:production, B:biomass, Q:consumption) for most groups were estimated from similar function groups in other ecopath models of the same latitude regions around. The value of EE (Ecotrophic Efficiency) is the main parameter to check the equilibration of the model. The EE parameters in the model are of high value (>0.808) for most groups, because the fishing pressure was very high and small living organisms were being heavily preyed upon in the ecosystem. The biomass density of the species commercially utilized estimated by the model is 12.33 ton穔m-2. Even though the value is low compared with the density in other ecosystems, such as Caribbean coral reef ecosystem and the Southern B.C. shelf model, it is higher than the value published by some papers on the Bohai Sea using other methods. Considering the lower value estimated by the stock assessment using bottom trawl survey data, the output here is reasonable. It is concluded that the biomass of commercial fishing species in the sea is 950 thousand metric tons, and 338 thousand tons are fish species in the value.
    Assimilation efficiency of pacific oyster Crassortrea gigas
    WANG Jun, JIANG Zuhui, ZHANG Bo, SUN Yao, TANG Qisheng
    2000, (3):  441-444. 
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    The effects of body size,food density and its quality on assimilation efficiency of pacific oyster (Crassostrea gigas) were studied under artificial conditions in laboratory.The experimental results show that the filtration and ingestion rates of pacific oyster increased with its body size,which tallied with power function.The assimilation efficiency of pacific oyster was not significantly correlated with its body size,but correlated positively with the organic matter content of food and negatively with food density.
    A preliminary study on influence of N and P on population constituent of planktonic diatoms in seawater
    QU Keming, CHEN Bijuan, YUAN Youxian, XIN Fuyan
    2000, (3):  445-448. 
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    Experiment was conducted to study the influence of N and P on population constiuent of planktonic diatoms in seawater.The concentrations of N and P and their ratios might significantly affect the population constituent of planktonic diatoms in seawater,the more the concentrations of N and P and the bigger the N/P ratio to Redfield ratio,the less the species of planktonic diatoms and Shannon's index.The experimental result was verified in the investigation from shrimp culturing ponds.
    Effects of salinity and alkalinity on plankton and water chemical factors
    SHENTU Qingchun, DONG Shuanglin, ZHAO Wen, ZHANG Zhaoqi
    2000, (3):  449-454. 
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    This paper dealt with the effects of increasing salinity and alkalinity on the chemical and hydrobiological factors in saline alkaline ponds.The experiment was conducted in Daluhu Aquaculture Company,Gaoqing County,Shandong Province during July and August,1998.Raw salt and NaHCO-3 were used to adjust the salinity and alkalinity.The results showed that increasing alkalinity from HCO-3- rsulted in the reduction of pH value,calcium ion concentration and COD in a short term.When alkalinity was increased from 6.64?0.40 to 13.47?0.31 mmol稬-1,no significant effect on plankton was observed. However,when salinity was increased from 2.10?0.22 to 11.29?0.99 g稬-1,it decreased the plankton biomass,species number and diversity index decreased,and affected the composition of plankton community structure.
    Concept of ecosystem management and its essential elements
    REN Hai, WU Jianguo, PENG Shaolin
    2000, (3):  455-458. 
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    Ecosystem management originates from the tradition fields of natural resources management and utilization,and develops in the 1990's.Based on our best understanding of the ecosystem composition,structure and function,and in definite spatiotemporal scales,it integrates human values and social-economic principles into managing ecosystems to resotre and/or sustain ecosystem integrity and sustainability.Ecosystem management requires the collection of field data and the monitoring of ecosystem dynamics at multiple scales.The essential elements of ecosystem management include clear management goals,definite ecological boundaries and units,sound ecological understanding,appropriate scale and hierarchic structure,understanding of ecosystem uncertainty,adaptive management,cooperation between agency and individuals,and viewing human and its value as ecosystem components.The goal of ecosystem management focuses on ecosystem sustainbility.
    Primary research on interface ecology in agroforestrial ecosystems
    WU Gang, LI Jing, DENG Hongbing
    2000, (3):  459-460. 
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    In this paper,the fundamental conception,major research content of interface ecology and its application in agroforestrial systems were discussed.The action mechanism between trees and crops in agroforestrial systems mainly embodied aboveground interface for competitve light,quantity of heat and water,and underground interface for competitiye nutrient and water. It was showed in the interchange and transmission of nutrient,energy and information through interface.
    Plant functional type and its significance in ecological research
    TANG Haiping, JIANG Gaoming
    2000, (3):  461-464. 
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    In recent years,plant functional type is a new ecological concept introduced in the research of global change.This paper reviewed the definition,classification,ecological significance of plant functional type.The theories and methodologies of systematic biology were used to understand the concept of plant functional type. And finally,the significance of this term in ecological studies,especially its role in the study of global change and terrestrial ecosystem was explained.
    BIOME 6000 Project:latest advances of reconstructing palaeobiome
    NI Jian
    2000, (3):  465-471. 
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    Global change research needs the data about the past states of the Earth system,e.g.,the pollen and plant macrofossil records for specified time slices (for example,the mid Holocene interval, ca 6,000 aBP,and the last glacial maximun,LGM, ca 18,000 aBP).In the past,the utilization of these palaeoecological data is mostly scattered and point fixed,and the reconstruction of palaeovegetation is often qualitatively descriptive.The establishment of international collaboration project BIOME 6000 (a global palaeovegetation mapping program)of the International Geosphere Biosphere Project (IGBP) breaks a new approach for the synthesis and quantitative study of palaeoecological data.In the projescts The methodology of biomization for assigning palaeoeclogical records to biomes is emphasized,in which,plant pollen taxa are assigned to one or more plant functional types (PFTs)by collecting widely global palaeoecological records which have quality assurance,and by using PFT definition based on the principles of modern ecology.Through combining PFTs into biome types,the global synthesis of biomes reconstructed by using palaeoecological data can be realized. The biomization method might provide a benchmark for coupled atmosphere-biosphere.This trend will facilitate biome mapping for other time slices,and co-evolution of atmosphere-biosphere modeling and palaeodata synthesis and analysis will continue.
    Some comments on ecological field
    WANG Deli
    2000, (3):  472-476. 
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    Based on the data of plant ecological field studies,this paper reviewed the conception of ecological field, field eigenfunctions, graphs of ecological field and its application of ecological field theory in explaining plant interactions.It is suggested that the basic character of ecological field is material, and based on the current research level, it is not sure whether ecological field is a kind of specific field different from general physical field.The author gave some comments on the formula and estimation of parameters of basic field function-ecological potential model on ecological field. Both models have their own characteristics and advantages in specific conditions. The author emphasized that ecological field had even more meaning of ecological methodology, and applying ecological field theory in describing the types and processes of plant interactions had three characteristics: quantitative, synthetic and intuitionistic. Field graphing might provide a new way to ecological studies, especially applying the ecological field theory might give an appropriate quantitative explanation for the dynamic process of plant populations (coexistence and interference competition).
    Advance in soil sampling methods in rhizosphere microzone study
    SU Baoling, HAN Shijie
    2000, (3):  477-480. 
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    Soil sampling methods in rhizosphere microzone study since 1960's were reviewed. It was suggested that the trend of rhizosphere soil sampling was from field coarse sampling to fine division of indoor simulated experiment. The simulated equipment was applied for field experiments, and the purpose guiding production practice could be achieved finally. Meanwhile, with the widening of the concept of rhizosphere, such as ecoboundary layer, rhizosphere soil sampling tends to keep unvarnished and fine.