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Table of Content

    15 February 2003, Volume 14 Issue 2
    Seedling establishment of Fagus engleriana,a dominant in mountain deciduous forests
    GUO Ke
    2003, (2):  161-164. 
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    The survival and growth of Fagus engleriana seedlings in three light levels,and with and without supplying additional fertilizer (F1 and F0, respectively) for each light level were studied. The three light levels were to simulate the light regimes in the understorey, small gaps and clearings (L1, L2 and L3 about 1%, 18% and 100% of full sunlight, respectively).The seedling development in L1 was severely inhibited by low light intensity. Seedling mortality was remarkably higher in L1 than in L2 and L3, and in F1 than in F0. The death of the seedlings seemed to result from attack of fungal pathogens. Although seedling survival and growth were significantly improved as light intensities increased from L1 to L2, seedlings in L3 developed similarly as those in L2. It is suggested that the young seedlings could not tolerate the shade of closed forest canopy, and fertile patches on the forest floor might not improve seedling establishment.Successful regeneration of the species in the forests needs better light conditions such as those in gaps than those under the closed forest canopy, at least during the phase of seedling establishment.
    Percentage of soil absolute moisture content at different succession stages of Castanopsis platyacantha-Schima sinensis formation in central subtropical zone of Sichuan Province
    PAN Kaiwen, ZHANG Yuanbin
    2003, (2):  165-169. 
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    The temporal spatial characteristics of the percentage of soil absolute moisture content (PSAMC, defined as the percentage of soil water to dried soil) at different succession stages of C.platyacantha S.sinensis formation such as brush, 10, 40, and 200 years old C.platyacantha S.sinensis communities were studied, using the methods of orientation observation and variance analysis under the similar conditions including climates, topographies, landforms, and soils. The results indicated that the relationship between soil depth and PSAMC of all communities except for 10 years old community were significant. The effects of season on PSAMC at different stages of all C.platyacantha S. sinensis communities was not significant. Similarly, aspect had no notable effects on PSAMC of all communities but 10 years old community. Different succession phases had significant effects on PSAMC (0~60cm depth). The water retention ability of soil was restored up to 73% and 85% of primary C. platyacantha S. sinensis forests when C.platyacantha S.sinensis communities were 10 and 40 years old. PSAMC of different succession phases of C.platyacantha S. sinensis had obvious characteristics of fluctuation and chaos.
    Energy situation of Sonneratia apetala-S caseloris forest in Futian of Shenzhen
    ZAN Qijie, WAN Bosun, WANG Yongjun
    2003, (2):  170-174. 
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    Based on the measurement of biomass and productivity, the caloric value of different fractions of two species in S.apetala-S.caseloris forest, and their standing crop of energy and net energy production were determined. There were some differences in caloric values among the fractions of S. apetala and S. caseloris, and the caloric value of leaf was the highest,while that of the fine roots was the lowest. The caloric values of various fractions of S.apetala were much higher than those of S.caseloris .The standing crop of energy in S.apetala S.caseloris forest was 84744.72 kJ穖-2 . The standing crop of energy accumulated in S. apetala population was 54693.26 kJ穖-2, accounting for 64.54 % of the total, and that of S.caseloris population was 30051.46 kJ穖-2, accounting for 35.46%. The energy return value of litters was 24549.54 kJ穖-2 穣r-1,that of S.apetala population was 17233.99 kJ穖-2 穣r-1 (accounting for 70.16%), and that of S.caseloris population was 7325.55 kJ穖-2 穣r-1 (29.84%).The net energy production was 50391.4 kJ穖-2 穣r-1 for S. apetala S. caseloris forest in1999, in which the net energy production of S. apetala population was 31778 kJ穖-2 穣r-1 .
    Growth and physiological features of Salix matsudana on the Mu Us Sandland in response to shading
    HE Weiming, DONG Ming
    2003, (2):  175-178. 
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    In a pot experiment, Salix matsudana was subjected to the unshaded, partial shading and shading treatments.The growth and physiological features of its branches were compared under contrasting light environments (i.e., the branches of entirely grew under unshaded condition (Bhh), entirely grew under shading condition (Bll), grew under unshaded condition and connected to different branches under shading condition (Bhl), and grew under shading condition and connected to different branches under unshaded condition (Blh)). The results showed that the leaf natality and mortality were higher in Bhl and Bll than in Bhh and Blh, respectively. Shading had significant effects on net photosynthesis and night respiration rates of four types of branches. The branch biomass, total branch length, shoot biomass and shoot weight ratio were higher in Bhl than in Bhh, and conversely, the number of branches, branch biomass, leaf area, leaf biomass, basal diameter, total branch length, shoot biomass and shoot weight ratio were smaller in Blh than in Bll.
    Soil basal respiration and enzyme activities in the root-layer soil of tea bushes in a red soil
    YU Shen, HE Zhenli, ZHANG Rongguang, CHEN Guochao, HUANG Changyong, ZHU Bingliang
    2003, (2):  179-183. 
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    Soil basal respiration potential, metabolic quotient (qCO2), and activities of urease, invertase and acid phosphomonoesterase were investigated in the root layer of 10, 40, and 90 yr old tea bushes grown on the same type of red soil. The soil daily basal respiration potential ranged from 36.23 to 58.52 mg·kg-1 ·d-1, and the potentials in the root layer of 40 or 90 yr old were greater than that of 10 yr old tea bushes.The daily qCO2, ranging from 0.30 to 0.68, was in the reverse trend. The activities of test three enzymes changed differently with tea bushes' age. Urease activity in the root layer of all age tea bushes ranged from 41.48 to 47.72 mg·kg-1 ·h-1 and slightly decreased with tea bushes' age. Invertase activity was 189.29~363.40 mg·kg-1 ·h-1 and decreased with tea bushes' age, but its activity in the root layer of 10 year old tea bushes was significantly greater than that in the root layer soil of 40 or 90 year old tea bushes. Acid phosphomonoesterase activity (444.22~828.32 mg·kg-1 ·h-1) increased significantly with tea bushes' age. Soil basal respiration potential, qCO2 and activities of 3 soil enzymes were closely related to soil pH, soil organic carbon, total nitrogen and C/Nratio, total soluble phenol, and microbial biomass carbon, respectively.
    Effects of amino acid-N and ammonium-N on wheat seedlings under sterile culture
    MO Liangyu, WU Lianghuan, TAO Qinnan
    2003, (2):  184-186. 
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    The dry weight, total N, and glutamate oxaloacetate transaminase(GOT) and glutamate pyruvate transaminase(GPT) activities in roots and leaves of wheat seedlings (Triticum aestivum) grown with ammonium sulfate or amino acids (glycine, glutamate or lysine) were studied under sterile sand culture. The results showed that both NH4+-N and amino acid-N could be absorbed by wheat. The total Nof plant fed with NH4+-N was similar to that fed with amino acid-N. The dry weight of plants grown30 days with glycine or glutamate was significantly higher than that of plants grown with NH4+-N or free N. The dry weight of ammonium treatment was similar to that of lysine treatment or free N. NH4+-N in concentration of 0.7 mmol稬-1 significantly increased GPTactivity of roots, but had no significant effects on leaves or roots treated 6 h in concentration of 35.7 mmol稬-1 . Different species or concentrations of amino acids had different abilities to increase the GOTor GPTactivity in leaves or roots.
    Role of Rhizobium in wheat-astragalus mixed cropping system
    ZHONG Zengtao, SHEN Qirong, SUN Xiaohong, RAN Wei, MAO Zesheng
    2003, (2):  187-190. 
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    Inoculation experiments were carried out in wheat astragalus mixed cropping system to study the changes of plant biomass, nitrogen content in plants and soil, and enzyme activity of Rhizobium . The results showed that in the mixed cropping system inoculated with Rhizobium, the growth of plants was stimulated, total nitrogen of plants and soil was increased significantly, and the increment of enzyme activity of Rhizobium was also found.
    Effect of sulfate supply level on characteristics of N and S metabolism and on root vigor of corn
    WANG Kongjun, HU Changhao, DONG Shuting, LIU Kaichang, LIU Cunhui
    2003, (2):  191-195. 
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    The effects of different sulfate supply level on N and S metabolism and on root vigor of corn were quantitatively studied with Hoagland solution under greenhouse conditions.The results showed that in S-deficient solution,root vigor and leaf nitrate reductase (NR) activity significantly rdduced,top root ratio (T/R) increased,and S and N accumulation in tops and roots decreased.The partition of Sdecreased in roots and incompletely expanded leaves,but increased in senescent leaves and sheaths stems ;while the partition of N increased in roots,but decreased in incompletely and fully expanded leaves.The content of protein,protein N,protein S,and sulfate Ssignificantly reduced, percentage of non protein N increased,inorganic S/total S ratio decreased,and total N/total Sratio increased.The protein N/ protein Sratio in tops had no observable changes.but increased significantly in roots,showing that root was a sensitive organ to S deficiency.There was a close relatioinship between protein content and NR activity in S-deficiency.D eficient or excessive S supply limited Nand Smetabolism of corn plant.N/Sor inorganic S/total Sratio in roots was a sensitive index to indicate the deficiency of Ssupply,which was 10.7 or 0.302 under normal condition,respectively.
    Dynamics of upland field P pool under a long-term application of fertilizer P in yellow soil area and their effects on P concentration in runoff
    LIU Fang, HUANG Changyong, HE Tengbin, QIAN Xiaogang, LIU Yuansheng, LUO Haibo
    2003, (2):  196-200. 
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    Studies on the dynamics of upland field P pool under a long term application of fertilizer-Pin yellow soil area and their effects on-Pconcentration in runoff showed that the contents of A1-P, Fe-P and Ca-P in soil cultivated layer increased greatly,and Olsen-P and algae available-Palso accumulated obviously. The correlation coefficients of algae available Pcontent in the high-P soils (Olsen-P>25 mg·kg-1) with the quantities of A1-P, Fe-P and Ca-P were 0.859**, 0.903** and 0.650*, respectively, of which,Fe-Pwas the most important. By a 30 min rainfall simulation experiment with a constant rainfall rate of 63.2 mm·h-1, the concentrations of dissolved reactive-Pand bio available-P in runoff from low-P upland fields (Olsen-P4.62~15.9 mg·kg-1) were 2.81~ 4.17 μg·L-1 and 0.723~0.876 mg·L-1, respectively, whereas their concentrations in runoff from high-P upland fields (Olsen-P29.4~59.2 mg·kg-1) were 0.026~0.714 mg·L-1 and 0.996~1.281 mg·L-1,respectively.Therefore,runoff from high-P upland fields could accelerate water eutrophication.
    Profile distribution of zinc forms under calcareous purple soil under different land use
    GAO Meirong, ZHU Bo, JIANG Mingfu, CHENG Yanao
    2003, (2):  201-204. 
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    The distribution of DTPA-Zn was influenced by other zinc forms in soil profile. In order to approach the mechanism of zinc deficiency in calcareous purple soil widely distributed in hilly regions of central Sichuan Province,four profiles(paddy field, dry land, K1c forest land and J3p forest land) under different land use were selected to study the distribution of other zinc forms. The results indicated that the distribution complication of zinc forms was in order of paddy field>dry land>forest land. The quantities of CAB-Zn(3.65%), TOM-Zn(2.81%) and COFe-Zn(22.04%) in farmland were evidently more than those (1.86%,0.84%,11.59%) in paddy field.
    Effects of plastic film mulching on soil temperature and moisture and on yield formation of spring wheat
    WANG Jun, LI Fengmin, SONG Qiuhua, LI Shiqing
    2003, (2):  205-210. 
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    Field experiments were carried out to study the effects of plastic film mulching on soil temperature and moisture, and on yield formation of spring wheat. The results showed that plastic film mulching could increase soil temperature with "U" variances in the whole growth period of spring wheat. Plastic film mulching could also increase soil available water by restraining evaporation and elevating deep water to the layer useable for roots. The promotion of soil temperature and soil water content under plastic film mulching was favorable to the development and water use of spring wheat in its earlier stage. Root developments were restrained when mulching in later stage of spring wheat, with decreases in crop water consumption and water use efficiency, and there was no significant effects on yield formation.The spring wheat yields under control (CK), pre sowing irrigation (W), mulching for whole stage (M), pre sowing irrigation adding mulching for 30 days (WM30), pre sowing irrigation adding mulching for 60 days (WM60), and pre sowing irrigation adding mulching for whole stage (WMw) were 2554, 2424, 2750, 3138, 3305, and 3123 kg·hm-2, respectively, and the optimum mulching time was at 40~60 days.
    Effect of soil water and fertilizer on soybean yield on loess slopeland
    CHEN Hongsong, SHAO Ming'an, ZHANG Xingchang
    2003, (2):  211-214. 
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    Studies on the effect of soil water and fertilizer on soybean yield on loess slope farmland showed that soybean yield (Y) increased linearly with the increase of water use efficiency (WUE).Soybean yield and WUE increase with the increase of Pfertilizer when Pfertilizer was applied alone,but increased firstly and then decreased with the increase of N fertilizer when N fertilizer was applied alone. Therefore, N fertilizer should be applied with Pfertilizer. Compared to no fertilizer, fertilizer could significantly increase soybean yield and WUE by 86.76%~470.16% and 69.64%~438.47%, respectively. Acombined application of N and P fertilizers could increase more soybean yield and WUE than applied each of them alone, and the rational ratio of N and P(P2O5) was 1.3:1.
    Effect of cutting periodicity on energy allocation and architecture of Trifolium repens
    BAO Guozhang, LI Xianglin, SHEN Wanbin, XIE Zhonglei, KANG Chunli
    2003, (2):  215-218. 
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    On the subtropical mountain swards, the effect of cutting periodicity on energy allocation, module density, number of branches and branching angle of T.repens were significant,With cutting periodicity raised, the energy allocation of stolon increased steadly,the caloric content of unit stolon dropped gradually,and the changing pattern of leaf density,stem density, branch number and internode's length was from low to high,and then to low.The branching intensity of T.repens ranged from 15 to 23.7 branches穖-2,and branching angle raried from 49.5皌o 60.2皐hile the cutting periodicity differed.
    Biogeochemical characteristics of nutrient elements in ungrazed grassland ecosystem in Xilin River Basin
    GENG Yuanbo, ZHANG Shen, DONG Yunshe, MENG Weiqi
    2003, (2):  219-222. 
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    The biogeochemical characteristics of nutrient elements in Leymus chinensis community and Stipa grandis community, which were both scarcely disturbed by human activities, in Xilin River Basin, Inner Mongolia were studied. The results showed that the storage of N, P, K, S, Ca, Mg, and Si in the soil compartment of soil plant system was higher than that in the plant subsystem of two communities,and their storage in the live shoots compartment was lower than that in the litter compartment. The disappearing rate of N, P, Kand Sfrom the litter compartment was higher than that of Ca, Mg, and Si in the two grassland communities.The decomposition rate of litter in Leymus chinensis community was higher than that in Stipa grandis community. In the grassland soil plant system,the matter flowing mass kept balance in Leymus chinensis community, but lost balance in Stipa grandis community. The matter participating in biogeochemical cycling in Leymus chinensis community was more than that in Stipa grandis community.
    Effect of prescribed burning on grassland nitrogen gross mineralization and nitrification
    LI Yuzhong, ZHU Tingcheng, LI Jiandong, ZHOU Daowei
    2003, (2):  223-226. 
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    The seasonal dynamics of nitrogen gross mineralization, nitrification,and mineral nitrogen consumption rates in burned and unburned Leymus chinensis grasslands were studied with 15N pool dilution technique . The results indicated that the gross mineralization and nitrification rates in burned area were higher than those in unburned area in April and May, and lower than those in unburned area in September. NH4+-N consumption rates were higher than unburned area in April and May, and lower in September. NO3--N consumption rates were higher than control in April and May, and lower than control in July and September. The NH4+-N concentrations were higher in burned area in April, May and July, and no difference in September.NO3--N concentrations were no difference between burned and unburned areas in April and May, and higher in burned areas in July and September.
    Physio-ecological characteristics of scallop Chlamys farreri
    ZHOU Yi, YANG Hongsheng, ZHANG Fusui
    2003, (2):  227-233. 
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    The physiological responses of scallop Chlamys farreri to changing environmental conditions were researched in semi-field water-flowing system, based on a recently developed biodeposition method. There was no significant relationship between clearance rate and stocking density or food concentration.The absorption efficiency of the scallops was not markedly affected by the stocking density and the POM. The mean POMabsorption efficiency was 75.9% and relatively high, which could be attributed to low food concentration. The energy loss by excretion of amino acid was higher than that by the excretion of ammonia. The gross ecological efficiency of N (mean value 9.9%) was higher than that of C (mean value 5.9%) or P(mean value 4.1%). In the nitrogen budget, if only NH4+-N was considered and other forms of nitrogen such as amino acids were neglected,a significant error (a mean about of 20%) could arise. It was suggested that whether in energy or element budget, the shell should not be neglected. In coastal intensive raft-culture areas, scallops might give great impact on energy flow and cyclings of matter and nutrient by filtration, respiration, excretion, egestion (biodeposition production) and growth.
    Daily change of primary productivity of phytoplankton in saline-alkaline ponds
    ZHAO Wen, DONG Shuang Lin, ZHANG Zhaoqi, SHENTU Qingchun
    2003, (2):  234-236. 
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    Daily change of the primary productivity of phytoplankton in saline alkaline ponds in Zhaodian Fishery Farm, Gaoqing County, Shandong Province, were estimated by means of dark and light bottle method, at the season of fish growth from April to September in1997. The results showed that the primary productivity of phytoplankton in saline alkaline ponds presents significant change during a day. And their distribution were correlated with some environmental factors such as light intensity, water temperature, the chlorophyll a concentration etc. The measured values of primary production in continual exposure for 24 hour with dark and light bottle methods were greatly lower than the accumulated values of exposure for 2 hour. It is proposed that diurnal production calculated by the results of exposure for 4 hour between10:00 and 14:00 was suitable in fish culture ponds.
    Influences of ration level and initial body weight on growth and size hierarchy of hybrid tilapia,Oreochromis mossambicus?Oniloticus
    WANG Yan
    2003, (2):  237-240. 
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    hybrid tilapia were distributed into twelve tanks, each stocked in six fish(A,B,C,D,E,F) with different body size. The initial body weight was 62.69?1.46 g for fish A, 56.48?1.30 g for B, 50.75?1.19 g for C, 35.56?1.18 g for D, 31.05?0.88 g for E, and 27.35?0.95 g for F (mean盨E). The fish were reared under four ration levels (deprived of feed, fed at 1.5% body weight per day (BW穌-1), fed at 3.0% BW穌-1, or fed excess) throughout four weeks, respectively.The specific growth rate (SGR) and feed efficiency (FE) of the fish increased with increasing ration level up to 3.0% BW穌-1, and then, SGRmaintained at a constant level while FEdropped with continuing increase of ration.The variance coefficient of SGRand final body weight was relatively high in the fish that fed at 1.5 % BW穌-1 .For fish A, SGR was not significantly different, between 1.5 %BW穌-1,3.0% BW穌-1 and fed excess, while in fish F,relatively high variations were found among different ration treatments. This experiment revealed that the growth and size hierarchy of hybrid tilapia were related to their ration level and initial body size. Under ration levels more than 3.0% BW穌-1, SGRwas usually high, and size hierarchy was relatively weak.
    Life-table of Helicoverpa armigera in Northern China and characters of population development in Southern and Northern China
    GE Feng, LIU Xianghui, DING Yanqin, WANG Xuezhi, ZHAO Yongfa
    2003, (2):  241-245. 
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    The population dynamics of Helicoverpa armigera in Raoyang County, Hebei Province as an example in Northern China was researched, and its natural life table was established.The results showed that total mortality of first to fourth generations of cotton bollworm in Northern China were 98.3%, 98.34%, 98.69% and 99.13 %, and the population tendency index (I) were 3.97, 1.50, 1.41 and 1.09, respectively.Acomparative analysis of the natural life table of cotton bollworm in Southern China and in Northern China showed that the survival curves were concave curves in the two cotton zones. The curve showed that the mortality of cotton bollworm was higher in its egg stage to the second instar, and lower after the third instar. The key death factor of cotton bollworm was the scouring effect of rain and wind in Southern China, and the predation of its natural enemies in Northern China. The hatch period to the first instar was the key stage in Northern China and Southern China, and in this time, its larva instar was slim, fragile and sensitive to bad circumstances, so its mortality was higher. The second and third generations were the key damage generations in Northern China, while the third and fourth generations were the key damage generations in Southern China. The development and damage characters of each generation in Northern China and in Southern China were discussed.
    HPLC analysis of main flavonoid chemicals and their spatio-temporal dynamics in Bt transgenic cotton
    ZHANG Yongjun, GUO Yuyuan, WU Kongming, WANG Wugang
    2003, (2):  246-248. 
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    Flavonoids are important chemicals of resistance to pests in cotton plant. The main flavonoid chemicals and their spatio temporal dynamics of content in Bt transgenic cotton were tested by HPLC. The results showed that the flavonoid chemicals of resistance to pests mainly including rutin, isoquercitrin and quercetin could be detected and quantitatively analyzed by HPLC. The contents of rutin, isoquercitrin and quercetin were the highest in petal, but lower in calyx, bract and cotton boll. Moreover, the total content of flavonoid chemicals in top leaf was much higher at developmental stage than at seedling stage. The content of each flavonoid chemicals of resistance to pests was different during different developmental stage and in different organs. It was indicated that different flavonoid chemicals played different roles in resistance to pests.
    Effect of plant alcohol extracts on vegetable aphids and their parasitoids
    ZHOU Qiong, LIANG Guangwen
    2003, (2):  249-252. 
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    The repelling and controlling effect of alcohol extracts from 8 common plant species on3 major vegetable aphids (Myzus persicae,Aphis gossypii and Lipaphis erysimi) were studied in the laboratory, and the effect on their parasitoid was also studied. The results showed that the test 8 plant species had some effects on3 aphids. The plant alcohol extracts from Tephrosia vogelli and Cinnamomum camphora had the most effect. The deterrent rate on Myzus persicae, Aphis gossypii and Lipaphis erysimi was 0.414, 0.729, 0.547 and 0.549, 0.690, 0.729, respectively. These 2 plants had the most controlling effect on3 aphids, too. The alcohol extract of Cinnamomum camphora was safely for parasitoids (Aphidius gifuensis and Diaeretiella rapae).
    Effect of free-air CO2 enrichment on biomass accumulation and distribution in rice
    HUANG Jianye, DONG Guichun, YANG Hongjian, WANG Yulong, ZHU Jianguo, YANG Lianxin, SHAN Yuhua
    2003, (2):  253-257. 
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    Investigation on the effect of free air CO2 enrichment (FACE) on biomass accumulation and distribution in different parts of rice plant treated with 200 μmol·mol-1 CO2 elevation under field condition showed that the dry matter accumulated from transplanting to 20th day after heading and the total biomass increased significantly, while the dry mater accumulated from20th day after heading to maturity was significantly depressed under FACEtreatment. The enhancement of both leaf area index (LAI) and net assimilation rate (NAR) under FACE treatment resulted in the increase of dry matter accumulated from transplanting to heading, while the dominant reason for the increase of dry matter accumulated during 20 days after heading was the slowed decline of LAI. The decline of dry matter accumulated from20th day to maturity was mainly caused by the decrease of NAR. The percentage of dry matter distributed in stem and sheath increased under FACEtreatment, while that in leaf decreased, and that in panicle showed no significant change. The content (%) and amount of soluble sugar and starch in stem and sheath at heading was significantly elevated under FACE.The grain yield of rice under FACEtreatment could be significantly improved by raising biomass.
    Effects of free air CO2 enrichment on rice canopy energy balance
    LUO Weihong, Mayumi Yoshimoto, DAI Jianfeng, ZHU Jianguo, HAN Yong, LIU Gang
    2003, (2):  258-262. 
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    The change of crop canopy energy balance will affect crop growth and development and its water use efficiency. In this study, the FACE system (setup at at Anzhen, Wuxi, Jiangsu Province in2001) was used to investigate the effects of FACE on rice canopy energy balance. The rice canopy microclimate observations were carried out from August 26 to October 13,2001 when the rice crops were at the heading to maturing stage.The results showed that the maximum difference of rice canopy sensible and latent heat fluxes between ambient and FACE occurred at the same time of minimum air humidity, i.e.,at about 14:00. From flowering to maturing stage, the maximum difference of rice canopy sensible and latent heat flux between FACE and ambient varied between 12~55 J·m-2 ·s-1 and -15~-65 J·m-2 ·s-1, respectively. The daytime total canopy sensible and latent heat fluxes of FACE were higher and lower than those of ambient, respectively, throughout flowering to maturing stage. The differences of daytime total canopy sensible and latent heat fluxes between ambient and FACE increased with the increase of net radiation above canopy during the same development stage, but decreased with the progress of the development stage. From flowering to maturing stage, the average difference of daytime total canopy latent heat flux between ambient and FACE was about 6.7%. FACE increased and decreased the ratio of daytime total canopy sensible and latent heat flux to daytime total net radiation above canopy, respectively, the ratio differences between FACE and ambient were 5.5%.
    Egretta garzetta as a bioindicator of environmental pollution in Tai Lake region
    RUAN Luzhang, ZHANG Yingmei, ZHAO Dongqin, DONG Yuanhua, Fasola Mauro
    2003, (2):  263-268. 
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    There were four species of Ardeidae in Tai Lake. The dominant vegetations in the habitat were Pinus massoniana, Cinnamomum hupehanum, Quercus acutissema, Ulmus prmila and Myrica rubra, which were suitable for Egretta garzetta to make nests. The area of the habitat was about 7 hm2, where there were totally 4200 Egretta garzetta nests with the density of 0.38 nest per tree in average. Studies on Egretta garzetta breeding ecology showed that the incubating time was 19~21 days,the average egg weight was 23.9±4.0 g(n =41), and the average egg size was 44.5±4.1 mm×32.6±4.9 mm(n =41). The mean clutch size and brood size were 5.02 (2~8) and 3.86(2~7), respectively, and the hatching rate was 84.25%. The measurements of Egretta garzetta nestling tarsus did not show any asymmetry (P>0.05). Egretta garzetta fed mainly on small fish and shrimps in Tai Lake. The analysis results of Tai Lake samples showed that the pollutants including HCH, HCB, cyclodience, DDTs (DDT, DDE and DDD), PCBs, Cr, Hg and Pb in Egretta garzetta eggs were detected except Cd,and these pollutants accumulated through prey chain from sediments and preys to nestlings. Comparing samples from Tai Lake and those from Poyang Lake as relatively unpolluted area, only the concentration of DDTs residues was higher than 2 μg·g-1 in both lakes,and the other residues from Tai Lake like organochlorine insecticides, PCBs and heavy metals were all lower than those from Poyang Lake, and did not affect the development and breeding success of Egretta garzetta at present.
    Behavior of HTO in simulated rice-water-soil ecosystem
    SHI Jianjun, GUO Jiangfeng
    2003, (2):  269-272. 
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    The behavior of transportation,accumulation and disappearance of HTO (tritium water) in a simulated rice water soil ecosystem was studied by using isotope tracer techniques for simulated pollutants, and the fitting equation was confirmed by application of the open three compartment system model and nonlinear regression method. The results showed that HTOin water was not only transferred to other compartments in the ecosystem, but also vaporized into atmosphere rapidly. Both free water tritium and bound tritium were found in the rice, and tritium of hygroscopic and crystalline water was consisted in the soil. The specific activity of free water tritium (or tritium of hygroscopic water) was stronger than that of bound tritium (or tritium of crystalline water). The specific activity of total tritium reduced after reaching the maximum in the rice and soil, and the bound tritium increased slowly. The specific activity of total tritium in stem was the strongest in the rice, and reached equipoise each other in the later stage gradually. The regression equations of accumulation and disappearance for the specific activity of total tritium in the water, soil and rice were given by analyzing the obtained data with exponential regression method. The analysis results of variance showed that each regression equation could describe the behavior of accumulation and disappearance of HTO in the rice water-soil ecosystems preferably.
    Content and extractability of heavy metals in cultivated soil in Fujian Province
    ZHANG Jinbiao, HUANG Weinan, CHEN Yusen, SU Nianhua, WANG Guo
    2003, (2):  273-276. 
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    The total and extractable contents of 7 heavy metals in cultivated soil in Fujian Province were determined. Statistical results indicated that the cultivated soil in Fujian Province was polluted by heavy metals, but different heavy metals caused different pollution levels. The extractable contents of heavy metals accounted for 10.0 to 52.2 % of total contents, varying with different heavy metals. There was a significantly positive correlation between total and extractable content of Cu, Zn, Cd, Pb, and Ni. Besides, Zn, Cd, Pb and As had a significantly positive correlation to each other, while only Zn had a significantly positive correlation to Ni, and Cu and Hg were not significantly correlated to any of other heavy metals.
    Purification of eutrophicated water body by Vetiveria zizanioids
    SI Youbin, BAO Junjie, CAO Deju, PENG Jun, Yang Qiang
    2003, (2):  277-279. 
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    Studies on the purification efficiency of eutrophicated water body by Vetiveria Zizanioids on floating beds showed that V. zizanioids had a great ability to remove TN, NH4+-N, TP, PO43-, COD, and BOD, and had a significant effect on improving water quality. It was proved that V.zizanioids could be used to purify the eutrophicated water body.
    Ecological footprint calculation and development capacity analysis of China in1999
    XU Zhongmin, ZHANG Zhiqiang, CHENG Guodong, CHEN Dongjing
    2003, (2):  280-285. 
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    The ecological footprint method put forward and improved by William Rees and Mathis Wackernagel presents a methodologically simple but integrated framework for national natural capital accounting, which is capable of measuring the impact of Human's consumption on ecosystem. Based on the ecological footprint theory and calculation method, a flow network analysis method was introduced to illuminate the structure of complex ecological economic system, and the relationship among ecological footprint, diversity and development capacity was analyzed.In this paper, the ecological footprints of China and its provinces was calculated and compared with the national and local ecological carrying capacity. The results showed that the ecological footprints of China and most of its provinces were beyond the available ecological capacity, and China and its most provinces run 'national or regional ecological deficit'. In case of China, the national ecological deficit was 0.645 hm2 per cap in1999. Secondly, we introduced a flow network analysis method,taking various ecological productive area as note, and adopted Ulanowicz's development capacity formula to analyze the relationship among ecological footprint diversity, development capacity and output. The results demonstrated that Ulanowicz's development capacity was a good predictor of economic system output. At the same time, two distinct ways to change development capacity were produced. Increasing ecological footprint or increasing ecological footprint's diversity would both increase development capacity. Due to the fact that the ecological footprints had already been beyond bio capacities, the only way to increase development capacity was to increase ecological footprint's diversity. The positive relationship between ecological footprint diversity and resources utilization efficiency demonstrated that there was no conflict between increasing ecological footprint's diversity and reducing footprints while not comprising our quality of life.
    Introduction and progress of molecular microbial ecology
    ZHANG Huiwen, ZHANG Qianru, ZHOU Qixing, ZHANG Chenggang
    2003, (2):  286-292. 
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    Molecular microbial ecology is an interdisciplinary field of molecular biological techniques and microbial ecology, which deals with microbial population, diversity, function, and relationships between microorganisms and biotic and abotic environments in microbial ecosystem. All the progress in molecular microbial ecology, especially in microbial diversity, phylogeny and communities of some microoganisms, indicate the renovation in traditional microbial ecology by the introduction of molecular techniques and strategies. This article reviewed the ideation,development, key domains, main methods and the future hot fields in molecular microbial ecology .
    Advances in studies on genetically engineered microorganism ecology
    JIN Suying, ZHANG Jiazhi, WANG Yanhong, MENG Shuying
    2003, (2):  293-295. 
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    Genetically engineered microorganism ecology has been one of main research contents in microorganism molecular ecology. Along with the introduction of molecular marker and molecular biology,traditional microorganism ecology has been developed; therefore, it is possible to study the relationship between GEM and environment, environmental microorganism under molecular level. The GEM ecology has become a new and intersection borderline discipline, related to molecular biology, microbiology, ecology and so on. Moreover, it brought forward that the prosecution of the research on the transgenic organism ecology and the risk assessment, and the foundation of checking means and valuating standard that adapt to the situation of China could help to the development of GEM ecology in China.
    Advances in vermiculture and inhibition of vermicompost to soil-borne disease
    HU Yanxia, SUN Zhenjun, CHENG Wenling
    2003, (2):  296-300. 
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    The transformation of organic wastes into useful resources by vermiculture has been a biological technology for ages, and obtained a new development in1970s. This paper mainly reviewed the methods of vermiculture, the physical and chemical aspects of vermicompost, and the comprehensive utilization of vermicompost, and emphasized the inhibition of vermicompost to soil borne disease. Although the mechanisms of inhibition have not been fully understood, the application has great potentiality. The disease inhibition is related with the microflora, especially the large number antagonisms enriched in vermicompost.
    On planning methods of sustainable eco-environmental management in mining areas
    LIU Ping, TANG Wanjin
    2003, (2):  301-304. 
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    Studies on the theory and methodology of ecological planning could provide material guide and technical support for sustainable development in mining areas. As one of the most important section of ecological planning in mining areas, sustainable eco environmental managing planning run through the whole producing course. On the basis of sustainable eco environmental construction and management, the framework of eco environmental management system of mining areas was established in this paper. The material methods for confirming the indexes of eco environmental management,recognizing the factory of eco environment and making the decision of eco environmental managing project were also provided.
    Effect of inorganic nitrogen on CH4 oxidation in soils
    WANG Zhiping, HU Chunsheng, YANG Jurong
    2003, (2):  305-309. 
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    The effects of N inputs,including N fertilizer applications and atmospheric Ndepositions, on CH4 oxidation by soils were determined by CH4 oxidizing bacteria, N inputs and soil factors. These effects were inhibitory or stimulative, but inhibition was more popular than stimulation, and the inhibition of NH4+ was more popular than that of NO3-. Wealthy experiments in different soils and climate regions are required to monitor and evaluate how N inputs influence CH4 oxidation in soils. Generally, CH4 oxidation in soils following N inputs showed multiple inhibition patterns, i.e., immediate or direct inhibition, delayed inhibition, and absence of inhibition. Some researchers explained the inhibition mechanism through using competition between CH4 and NH4+ for the same enzyme sites, elevated threshold, salt effect and ion exchange, and N turnover rate and N concentration. However, the inhibitory mechanism is still unclear. Therefore, inhibitory mechanism is one of the main research concerns in future.
    Advances of studies on the effects of plant volatiles on insect behavior
    YAN Shanchun, ZHANG Dandan, CHI Defu
    2003, (2):  310-313. 
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    Plant volatiles show different effects on insect behaviors, which included luring, repelling and killing. After damaged by phytophagous insects, some host plants could send volatiles luring natural enemies as an indirect defense. Asummarize on the new advances of plant volatiles was given. The role of plant volatiles in integrated pest management in future was also discussed.
    Discussion on several indices assessing landscape dispersion
    JIN Weibin, HU Bingmin
    2003, (2):  314-316. 
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    Several indices assessing landscape dispersion, such as isolation, type divergence and nearest neighbor index, were compared. Different indices could reflect different aspects of landscape dispersion. Dispersion index was suggested to assess the dispersion more comprehensively. All the indices were computed to study the landscape dispersion in a valley basin, and the results showed that dispersion index was better to synthesize information and to be in line with practice than others.
    Preliminary study on ecological footprint in Bashang region of Zhangjiakou city
    HU Mengchun, ZHANG Yongchun, MIAO Xubo, SHEN Weishou, MA Ronghua
    2003, (2):  317-320. 
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    The ecological footprint and ecological carrying capacity in Bashang region of Zhangjiakou city were calculated with the statistical data of the region in1999. Based on calculation, the balance between ecological footprint and ecological carrying capacity was analyzed, and the threshold values of the ecological carrying capacity and population capacity of the region at the current production level were determined. Strategies on reducing ecological deficit in this region were also brought forward.
    Seedling establishment of Fagus engleriana,a dominant in mountain deciduous forests
    GUO Ke
    2003, (2):  161-164. 
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    The survival and growth of Fagus engleriana seedlings in three light levels,and with and without supplying additional fertilizer (F1 and F0, respectively) for each light level were studied. The three light levels were to simulate the light regimes in the understorey, small gaps and clearings (L1, L2 and L3 about 1%, 18% and 100% of full sunlight, respectively).The seedling development in L1 was severely inhibited by low light intensity. Seedling mortality was remarkably higher in L1 than in L2 and L3, and in F1 than in F0. The death of the seedlings seemed to result from attack of fungal pathogens. Although seedling survival and growth were significantly improved as light intensities increased from L1 to L2, seedlings in L3 developed similarly as those in L2. It is suggested that the young seedlings could not tolerate the shade of closed forest canopy, and fertile patches on the forest floor might not improve seedling establishment.Successful regeneration of the species in the forests needs better light conditions such as those in gaps than those under the closed forest canopy, at least during the phase of seedling establishment.
    Percentage of soil absolute moisture content at different succession stages of Castanopsis platyacantha-Schima sinensis formation in central subtropical zone of Sichuan Province
    PAN Kaiwen, ZHANG Yuanbin
    2003, (2):  165-169. 
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    The temporal spatial characteristics of the percentage of soil absolute moisture content (PSAMC, defined as the percentage of soil water to dried soil) at different succession stages of C.platyacantha S.sinensis formation such as brush, 10, 40, and 200 years old C.platyacantha S.sinensis communities were studied, using the methods of orientation observation and variance analysis under the similar conditions including climates, topographies, landforms, and soils. The results indicated that the relationship between soil depth and PSAMC of all communities except for 10 years old community were significant. The effects of season on PSAMC at different stages of all C.platyacantha S. sinensis communities was not significant. Similarly, aspect had no notable effects on PSAMC of all communities but 10 years old community. Different succession phases had significant effects on PSAMC (0~60cm depth). The water retention ability of soil was restored up to 73% and 85% of primary C. platyacantha S. sinensis forests when C.platyacantha S.sinensis communities were 10 and 40 years old. PSAMC of different succession phases of C.platyacantha S. sinensis had obvious characteristics of fluctuation and chaos.
    Energy situation of Sonneratia apetala-S caseloris forest in Futian of Shenzhen
    ZAN Qijie, WAN Bosun, WANG Yongjun
    2003, (2):  170-174. 
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    Based on the measurement of biomass and productivity, the caloric value of different fractions of two species in S.apetala-S.caseloris forest, and their standing crop of energy and net energy production were determined. There were some differences in caloric values among the fractions of S. apetala and S. caseloris, and the caloric value of leaf was the highest,while that of the fine roots was the lowest. The caloric values of various fractions of S.apetala were much higher than those of S.caseloris .The standing crop of energy in S.apetala S.caseloris forest was 84744.72 kJ穖-2 . The standing crop of energy accumulated in S. apetala population was 54693.26 kJ穖-2, accounting for 64.54 % of the total, and that of S.caseloris population was 30051.46 kJ穖-2, accounting for 35.46%. The energy return value of litters was 24549.54 kJ穖-2 穣r-1,that of S.apetala population was 17233.99 kJ穖-2 穣r-1 (accounting for 70.16%), and that of S.caseloris population was 7325.55 kJ穖-2 穣r-1 (29.84%).The net energy production was 50391.4 kJ穖-2 穣r-1 for S. apetala S. caseloris forest in1999, in which the net energy production of S. apetala population was 31778 kJ穖-2 穣r-1 .
    Growth and physiological features of Salix matsudana on the Mu Us Sandland in response to shading
    HE Weiming, DONG Ming
    2003, (2):  175-178. 
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    In a pot experiment, Salix matsudana was subjected to the unshaded, partial shading and shading treatments.The growth and physiological features of its branches were compared under contrasting light environments (i.e., the branches of entirely grew under unshaded condition (Bhh), entirely grew under shading condition (Bll), grew under unshaded condition and connected to different branches under shading condition (Bhl), and grew under shading condition and connected to different branches under unshaded condition (Blh)). The results showed that the leaf natality and mortality were higher in Bhl and Bll than in Bhh and Blh, respectively. Shading had significant effects on net photosynthesis and night respiration rates of four types of branches. The branch biomass, total branch length, shoot biomass and shoot weight ratio were higher in Bhl than in Bhh, and conversely, the number of branches, branch biomass, leaf area, leaf biomass, basal diameter, total branch length, shoot biomass and shoot weight ratio were smaller in Blh than in Bll.
    Soil basal respiration and enzyme activities in the root-layer soil of tea bushes in a red soil
    YU Shen, HE Zhenli, ZHANG Rongguang, CHEN Guochao, HUANG Changyong, ZHU Bingliang
    2003, (2):  179-183. 
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    Soil basal respiration potential, metabolic quotient (qCO2), and activities of urease, invertase and acid phosphomonoesterase were investigated in the root layer of 10, 40, and 90 yr old tea bushes grown on the same type of red soil. The soil daily basal respiration potential ranged from 36.23 to 58.52 mg·kg-1 ·d-1, and the potentials in the root layer of 40 or 90 yr old were greater than that of 10 yr old tea bushes.The daily qCO2, ranging from 0.30 to 0.68, was in the reverse trend. The activities of test three enzymes changed differently with tea bushes' age. Urease activity in the root layer of all age tea bushes ranged from 41.48 to 47.72 mg·kg-1 ·h-1 and slightly decreased with tea bushes' age. Invertase activity was 189.29~363.40 mg·kg-1 ·h-1 and decreased with tea bushes' age, but its activity in the root layer of 10 year old tea bushes was significantly greater than that in the root layer soil of 40 or 90 year old tea bushes. Acid phosphomonoesterase activity (444.22~828.32 mg·kg-1 ·h-1) increased significantly with tea bushes' age. Soil basal respiration potential, qCO2 and activities of 3 soil enzymes were closely related to soil pH, soil organic carbon, total nitrogen and C/Nratio, total soluble phenol, and microbial biomass carbon, respectively.
    Effects of amino acid-N and ammonium-N on wheat seedlings under sterile culture
    MO Liangyu, WU Lianghuan, TAO Qinnan
    2003, (2):  184-186. 
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    The dry weight, total N, and glutamate oxaloacetate transaminase(GOT) and glutamate pyruvate transaminase(GPT) activities in roots and leaves of wheat seedlings (Triticum aestivum) grown with ammonium sulfate or amino acids (glycine, glutamate or lysine) were studied under sterile sand culture. The results showed that both NH4+-N and amino acid-N could be absorbed by wheat. The total Nof plant fed with NH4+-N was similar to that fed with amino acid-N. The dry weight of plants grown30 days with glycine or glutamate was significantly higher than that of plants grown with NH4+-N or free N. The dry weight of ammonium treatment was similar to that of lysine treatment or free N. NH4+-N in concentration of 0.7 mmol稬-1 significantly increased GPTactivity of roots, but had no significant effects on leaves or roots treated 6 h in concentration of 35.7 mmol稬-1 . Different species or concentrations of amino acids had different abilities to increase the GOTor GPTactivity in leaves or roots.
    Role of Rhizobium in wheat-astragalus mixed cropping system
    ZHONG Zengtao, SHEN Qirong, SUN Xiaohong, RAN Wei, MAO Zesheng
    2003, (2):  187-190. 
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    Inoculation experiments were carried out in wheat astragalus mixed cropping system to study the changes of plant biomass, nitrogen content in plants and soil, and enzyme activity of Rhizobium . The results showed that in the mixed cropping system inoculated with Rhizobium, the growth of plants was stimulated, total nitrogen of plants and soil was increased significantly, and the increment of enzyme activity of Rhizobium was also found.
    Effect of sulfate supply level on characteristics of N and S metabolism and on root vigor of corn
    WANG Kongjun, HU Changhao, DONG Shuting, LIU Kaichang, LIU Cunhui
    2003, (2):  191-195. 
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    The effects of different sulfate supply level on N and S metabolism and on root vigor of corn were quantitatively studied with Hoagland solution under greenhouse conditions.The results showed that in S-deficient solution,root vigor and leaf nitrate reductase (NR) activity significantly rdduced,top root ratio (T/R) increased,and S and N accumulation in tops and roots decreased.The partition of Sdecreased in roots and incompletely expanded leaves,but increased in senescent leaves and sheaths stems ;while the partition of N increased in roots,but decreased in incompletely and fully expanded leaves.The content of protein,protein N,protein S,and sulfate Ssignificantly reduced, percentage of non protein N increased,inorganic S/total S ratio decreased,and total N/total Sratio increased.The protein N/ protein Sratio in tops had no observable changes.but increased significantly in roots,showing that root was a sensitive organ to S deficiency.There was a close relatioinship between protein content and NR activity in S-deficiency.D eficient or excessive S supply limited Nand Smetabolism of corn plant.N/Sor inorganic S/total Sratio in roots was a sensitive index to indicate the deficiency of Ssupply,which was 10.7 or 0.302 under normal condition,respectively.
    Dynamics of upland field P pool under a long-term application of fertilizer P in yellow soil area and their effects on P concentration in runoff
    LIU Fang, HUANG Changyong, HE Tengbin, QIAN Xiaogang, LIU Yuansheng, LUO Haibo
    2003, (2):  196-200. 
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    Studies on the dynamics of upland field P pool under a long term application of fertilizer-Pin yellow soil area and their effects on-Pconcentration in runoff showed that the contents of A1-P, Fe-P and Ca-P in soil cultivated layer increased greatly,and Olsen-P and algae available-Palso accumulated obviously. The correlation coefficients of algae available Pcontent in the high-P soils (Olsen-P>25 mg·kg-1) with the quantities of A1-P, Fe-P and Ca-P were 0.859**, 0.903** and 0.650*, respectively, of which,Fe-Pwas the most important. By a 30 min rainfall simulation experiment with a constant rainfall rate of 63.2 mm·h-1, the concentrations of dissolved reactive-Pand bio available-P in runoff from low-P upland fields (Olsen-P4.62~15.9 mg·kg-1) were 2.81~ 4.17 μg·L-1 and 0.723~0.876 mg·L-1, respectively, whereas their concentrations in runoff from high-P upland fields (Olsen-P29.4~59.2 mg·kg-1) were 0.026~0.714 mg·L-1 and 0.996~1.281 mg·L-1,respectively.Therefore,runoff from high-P upland fields could accelerate water eutrophication.
    Profile distribution of zinc forms under calcareous purple soil under different land use
    GAO Meirong, ZHU Bo, JIANG Mingfu, CHENG Yanao
    2003, (2):  201-204. 
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    The distribution of DTPA-Zn was influenced by other zinc forms in soil profile. In order to approach the mechanism of zinc deficiency in calcareous purple soil widely distributed in hilly regions of central Sichuan Province,four profiles(paddy field, dry land, K1c forest land and J3p forest land) under different land use were selected to study the distribution of other zinc forms. The results indicated that the distribution complication of zinc forms was in order of paddy field>dry land>forest land. The quantities of CAB-Zn(3.65%), TOM-Zn(2.81%) and COFe-Zn(22.04%) in farmland were evidently more than those (1.86%,0.84%,11.59%) in paddy field.
    Effects of plastic film mulching on soil temperature and moisture and on yield formation of spring wheat
    WANG Jun, LI Fengmin, SONG Qiuhua, LI Shiqing
    2003, (2):  205-210. 
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    Field experiments were carried out to study the effects of plastic film mulching on soil temperature and moisture, and on yield formation of spring wheat. The results showed that plastic film mulching could increase soil temperature with "U" variances in the whole growth period of spring wheat. Plastic film mulching could also increase soil available water by restraining evaporation and elevating deep water to the layer useable for roots. The promotion of soil temperature and soil water content under plastic film mulching was favorable to the development and water use of spring wheat in its earlier stage. Root developments were restrained when mulching in later stage of spring wheat, with decreases in crop water consumption and water use efficiency, and there was no significant effects on yield formation.The spring wheat yields under control (CK), pre sowing irrigation (W), mulching for whole stage (M), pre sowing irrigation adding mulching for 30 days (WM30), pre sowing irrigation adding mulching for 60 days (WM60), and pre sowing irrigation adding mulching for whole stage (WMw) were 2554, 2424, 2750, 3138, 3305, and 3123 kg·hm-2, respectively, and the optimum mulching time was at 40~60 days.
    Effect of soil water and fertilizer on soybean yield on loess slopeland
    CHEN Hongsong, SHAO Ming'an, ZHANG Xingchang
    2003, (2):  211-214. 
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    Studies on the effect of soil water and fertilizer on soybean yield on loess slope farmland showed that soybean yield (Y) increased linearly with the increase of water use efficiency (WUE).Soybean yield and WUE increase with the increase of Pfertilizer when Pfertilizer was applied alone,but increased firstly and then decreased with the increase of N fertilizer when N fertilizer was applied alone. Therefore, N fertilizer should be applied with Pfertilizer. Compared to no fertilizer, fertilizer could significantly increase soybean yield and WUE by 86.76%~470.16% and 69.64%~438.47%, respectively. Acombined application of N and P fertilizers could increase more soybean yield and WUE than applied each of them alone, and the rational ratio of N and P(P2O5) was 1.3:1.
    Effect of cutting periodicity on energy allocation and architecture of Trifolium repens
    BAO Guozhang, LI Xianglin, SHEN Wanbin, XIE Zhonglei, KANG Chunli
    2003, (2):  215-218. 
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    On the subtropical mountain swards, the effect of cutting periodicity on energy allocation, module density, number of branches and branching angle of T.repens were significant,With cutting periodicity raised, the energy allocation of stolon increased steadly,the caloric content of unit stolon dropped gradually,and the changing pattern of leaf density,stem density, branch number and internode's length was from low to high,and then to low.The branching intensity of T.repens ranged from 15 to 23.7 branches穖-2,and branching angle raried from 49.5皌o 60.2皐hile the cutting periodicity differed.
    Biogeochemical characteristics of nutrient elements in ungrazed grassland ecosystem in Xilin River Basin
    GENG Yuanbo, ZHANG Shen, DONG Yunshe, MENG Weiqi
    2003, (2):  219-222. 
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    The biogeochemical characteristics of nutrient elements in Leymus chinensis community and Stipa grandis community, which were both scarcely disturbed by human activities, in Xilin River Basin, Inner Mongolia were studied. The results showed that the storage of N, P, K, S, Ca, Mg, and Si in the soil compartment of soil plant system was higher than that in the plant subsystem of two communities,and their storage in the live shoots compartment was lower than that in the litter compartment. The disappearing rate of N, P, Kand Sfrom the litter compartment was higher than that of Ca, Mg, and Si in the two grassland communities.The decomposition rate of litter in Leymus chinensis community was higher than that in Stipa grandis community. In the grassland soil plant system,the matter flowing mass kept balance in Leymus chinensis community, but lost balance in Stipa grandis community. The matter participating in biogeochemical cycling in Leymus chinensis community was more than that in Stipa grandis community.
    Effect of prescribed burning on grassland nitrogen gross mineralization and nitrification
    LI Yuzhong, ZHU Tingcheng, LI Jiandong, ZHOU Daowei
    2003, (2):  223-226. 
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    The seasonal dynamics of nitrogen gross mineralization, nitrification,and mineral nitrogen consumption rates in burned and unburned Leymus chinensis grasslands were studied with 15N pool dilution technique . The results indicated that the gross mineralization and nitrification rates in burned area were higher than those in unburned area in April and May, and lower than those in unburned area in September. NH4+-N consumption rates were higher than unburned area in April and May, and lower in September. NO3--N consumption rates were higher than control in April and May, and lower than control in July and September. The NH4+-N concentrations were higher in burned area in April, May and July, and no difference in September.NO3--N concentrations were no difference between burned and unburned areas in April and May, and higher in burned areas in July and September.
    Physio-ecological characteristics of scallop Chlamys farreri
    ZHOU Yi, YANG Hongsheng, ZHANG Fusui
    2003, (2):  227-233. 
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    The physiological responses of scallop Chlamys farreri to changing environmental conditions were researched in semi-field water-flowing system, based on a recently developed biodeposition method. There was no significant relationship between clearance rate and stocking density or food concentration.The absorption efficiency of the scallops was not markedly affected by the stocking density and the POM. The mean POMabsorption efficiency was 75.9% and relatively high, which could be attributed to low food concentration. The energy loss by excretion of amino acid was higher than that by the excretion of ammonia. The gross ecological efficiency of N (mean value 9.9%) was higher than that of C (mean value 5.9%) or P(mean value 4.1%). In the nitrogen budget, if only NH4+-N was considered and other forms of nitrogen such as amino acids were neglected,a significant error (a mean about of 20%) could arise. It was suggested that whether in energy or element budget, the shell should not be neglected. In coastal intensive raft-culture areas, scallops might give great impact on energy flow and cyclings of matter and nutrient by filtration, respiration, excretion, egestion (biodeposition production) and growth.
    Daily change of primary productivity of phytoplankton in saline-alkaline ponds
    ZHAO Wen, DONG Shuang Lin, ZHANG Zhaoqi, SHENTU Qingchun
    2003, (2):  234-236. 
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    Daily change of the primary productivity of phytoplankton in saline alkaline ponds in Zhaodian Fishery Farm, Gaoqing County, Shandong Province, were estimated by means of dark and light bottle method, at the season of fish growth from April to September in1997. The results showed that the primary productivity of phytoplankton in saline alkaline ponds presents significant change during a day. And their distribution were correlated with some environmental factors such as light intensity, water temperature, the chlorophyll a concentration etc. The measured values of primary production in continual exposure for 24 hour with dark and light bottle methods were greatly lower than the accumulated values of exposure for 2 hour. It is proposed that diurnal production calculated by the results of exposure for 4 hour between10:00 and 14:00 was suitable in fish culture ponds.
    Influences of ration level and initial body weight on growth and size hierarchy of hybrid tilapia,Oreochromis mossambicus?Oniloticus
    WANG Yan
    2003, (2):  237-240. 
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    hybrid tilapia were distributed into twelve tanks, each stocked in six fish(A,B,C,D,E,F) with different body size. The initial body weight was 62.69?1.46 g for fish A, 56.48?1.30 g for B, 50.75?1.19 g for C, 35.56?1.18 g for D, 31.05?0.88 g for E, and 27.35?0.95 g for F (mean盨E). The fish were reared under four ration levels (deprived of feed, fed at 1.5% body weight per day (BW穌-1), fed at 3.0% BW穌-1, or fed excess) throughout four weeks, respectively.The specific growth rate (SGR) and feed efficiency (FE) of the fish increased with increasing ration level up to 3.0% BW穌-1, and then, SGRmaintained at a constant level while FEdropped with continuing increase of ration.The variance coefficient of SGRand final body weight was relatively high in the fish that fed at 1.5 % BW穌-1 .For fish A, SGR was not significantly different, between 1.5 %BW穌-1,3.0% BW穌-1 and fed excess, while in fish F,relatively high variations were found among different ration treatments. This experiment revealed that the growth and size hierarchy of hybrid tilapia were related to their ration level and initial body size. Under ration levels more than 3.0% BW穌-1, SGRwas usually high, and size hierarchy was relatively weak.
    Life-table of Helicoverpa armigera in Northern China and characters of population development in Southern and Northern China
    GE Feng, LIU Xianghui, DING Yanqin, WANG Xuezhi, ZHAO Yongfa
    2003, (2):  241-245. 
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    The population dynamics of Helicoverpa armigera in Raoyang County, Hebei Province as an example in Northern China was researched, and its natural life table was established.The results showed that total mortality of first to fourth generations of cotton bollworm in Northern China were 98.3%, 98.34%, 98.69% and 99.13 %, and the population tendency index (I) were 3.97, 1.50, 1.41 and 1.09, respectively.Acomparative analysis of the natural life table of cotton bollworm in Southern China and in Northern China showed that the survival curves were concave curves in the two cotton zones. The curve showed that the mortality of cotton bollworm was higher in its egg stage to the second instar, and lower after the third instar. The key death factor of cotton bollworm was the scouring effect of rain and wind in Southern China, and the predation of its natural enemies in Northern China. The hatch period to the first instar was the key stage in Northern China and Southern China, and in this time, its larva instar was slim, fragile and sensitive to bad circumstances, so its mortality was higher. The second and third generations were the key damage generations in Northern China, while the third and fourth generations were the key damage generations in Southern China. The development and damage characters of each generation in Northern China and in Southern China were discussed.
    HPLC analysis of main flavonoid chemicals and their spatio-temporal dynamics in Bt transgenic cotton
    ZHANG Yongjun, GUO Yuyuan, WU Kongming, WANG Wugang
    2003, (2):  246-248. 
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    Flavonoids are important chemicals of resistance to pests in cotton plant. The main flavonoid chemicals and their spatio temporal dynamics of content in Bt transgenic cotton were tested by HPLC. The results showed that the flavonoid chemicals of resistance to pests mainly including rutin, isoquercitrin and quercetin could be detected and quantitatively analyzed by HPLC. The contents of rutin, isoquercitrin and quercetin were the highest in petal, but lower in calyx, bract and cotton boll. Moreover, the total content of flavonoid chemicals in top leaf was much higher at developmental stage than at seedling stage. The content of each flavonoid chemicals of resistance to pests was different during different developmental stage and in different organs. It was indicated that different flavonoid chemicals played different roles in resistance to pests.
    Effect of plant alcohol extracts on vegetable aphids and their parasitoids
    ZHOU Qiong, LIANG Guangwen
    2003, (2):  249-252. 
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    The repelling and controlling effect of alcohol extracts from 8 common plant species on3 major vegetable aphids (Myzus persicae,Aphis gossypii and Lipaphis erysimi) were studied in the laboratory, and the effect on their parasitoid was also studied. The results showed that the test 8 plant species had some effects on3 aphids. The plant alcohol extracts from Tephrosia vogelli and Cinnamomum camphora had the most effect. The deterrent rate on Myzus persicae, Aphis gossypii and Lipaphis erysimi was 0.414, 0.729, 0.547 and 0.549, 0.690, 0.729, respectively. These 2 plants had the most controlling effect on3 aphids, too. The alcohol extract of Cinnamomum camphora was safely for parasitoids (Aphidius gifuensis and Diaeretiella rapae).
    Effect of free-air CO2 enrichment on biomass accumulation and distribution in rice
    HUANG Jianye, DONG Guichun, YANG Hongjian, WANG Yulong, ZHU Jianguo, YANG Lianxin, SHAN Yuhua
    2003, (2):  253-257. 
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    Investigation on the effect of free air CO2 enrichment (FACE) on biomass accumulation and distribution in different parts of rice plant treated with 200 μmol·mol-1 CO2 elevation under field condition showed that the dry matter accumulated from transplanting to 20th day after heading and the total biomass increased significantly, while the dry mater accumulated from20th day after heading to maturity was significantly depressed under FACEtreatment. The enhancement of both leaf area index (LAI) and net assimilation rate (NAR) under FACE treatment resulted in the increase of dry matter accumulated from transplanting to heading, while the dominant reason for the increase of dry matter accumulated during 20 days after heading was the slowed decline of LAI. The decline of dry matter accumulated from20th day to maturity was mainly caused by the decrease of NAR. The percentage of dry matter distributed in stem and sheath increased under FACEtreatment, while that in leaf decreased, and that in panicle showed no significant change. The content (%) and amount of soluble sugar and starch in stem and sheath at heading was significantly elevated under FACE.The grain yield of rice under FACEtreatment could be significantly improved by raising biomass.
    Effects of free air CO2 enrichment on rice canopy energy balance
    LUO Weihong, Mayumi Yoshimoto, DAI Jianfeng, ZHU Jianguo, HAN Yong, LIU Gang
    2003, (2):  258-262. 
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    The change of crop canopy energy balance will affect crop growth and development and its water use efficiency. In this study, the FACE system (setup at at Anzhen, Wuxi, Jiangsu Province in2001) was used to investigate the effects of FACE on rice canopy energy balance. The rice canopy microclimate observations were carried out from August 26 to October 13,2001 when the rice crops were at the heading to maturing stage.The results showed that the maximum difference of rice canopy sensible and latent heat fluxes between ambient and FACE occurred at the same time of minimum air humidity, i.e.,at about 14:00. From flowering to maturing stage, the maximum difference of rice canopy sensible and latent heat flux between FACE and ambient varied between 12~55 J·m-2 ·s-1 and -15~-65 J·m-2 ·s-1, respectively. The daytime total canopy sensible and latent heat fluxes of FACE were higher and lower than those of ambient, respectively, throughout flowering to maturing stage. The differences of daytime total canopy sensible and latent heat fluxes between ambient and FACE increased with the increase of net radiation above canopy during the same development stage, but decreased with the progress of the development stage. From flowering to maturing stage, the average difference of daytime total canopy latent heat flux between ambient and FACE was about 6.7%. FACE increased and decreased the ratio of daytime total canopy sensible and latent heat flux to daytime total net radiation above canopy, respectively, the ratio differences between FACE and ambient were 5.5%.
    Egretta garzetta as a bioindicator of environmental pollution in Tai Lake region
    RUAN Luzhang, ZHANG Yingmei, ZHAO Dongqin, DONG Yuanhua, Fasola Mauro
    2003, (2):  263-268. 
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    There were four species of Ardeidae in Tai Lake. The dominant vegetations in the habitat were Pinus massoniana, Cinnamomum hupehanum, Quercus acutissema, Ulmus prmila and Myrica rubra, which were suitable for Egretta garzetta to make nests. The area of the habitat was about 7 hm2, where there were totally 4200 Egretta garzetta nests with the density of 0.38 nest per tree in average. Studies on Egretta garzetta breeding ecology showed that the incubating time was 19~21 days,the average egg weight was 23.9±4.0 g(n =41), and the average egg size was 44.5±4.1 mm×32.6±4.9 mm(n =41). The mean clutch size and brood size were 5.02 (2~8) and 3.86(2~7), respectively, and the hatching rate was 84.25%. The measurements of Egretta garzetta nestling tarsus did not show any asymmetry (P>0.05). Egretta garzetta fed mainly on small fish and shrimps in Tai Lake. The analysis results of Tai Lake samples showed that the pollutants including HCH, HCB, cyclodience, DDTs (DDT, DDE and DDD), PCBs, Cr, Hg and Pb in Egretta garzetta eggs were detected except Cd,and these pollutants accumulated through prey chain from sediments and preys to nestlings. Comparing samples from Tai Lake and those from Poyang Lake as relatively unpolluted area, only the concentration of DDTs residues was higher than 2 μg·g-1 in both lakes,and the other residues from Tai Lake like organochlorine insecticides, PCBs and heavy metals were all lower than those from Poyang Lake, and did not affect the development and breeding success of Egretta garzetta at present.
    Behavior of HTO in simulated rice-water-soil ecosystem
    SHI Jianjun, GUO Jiangfeng
    2003, (2):  269-272. 
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    The behavior of transportation,accumulation and disappearance of HTO (tritium water) in a simulated rice water soil ecosystem was studied by using isotope tracer techniques for simulated pollutants, and the fitting equation was confirmed by application of the open three compartment system model and nonlinear regression method. The results showed that HTOin water was not only transferred to other compartments in the ecosystem, but also vaporized into atmosphere rapidly. Both free water tritium and bound tritium were found in the rice, and tritium of hygroscopic and crystalline water was consisted in the soil. The specific activity of free water tritium (or tritium of hygroscopic water) was stronger than that of bound tritium (or tritium of crystalline water). The specific activity of total tritium reduced after reaching the maximum in the rice and soil, and the bound tritium increased slowly. The specific activity of total tritium in stem was the strongest in the rice, and reached equipoise each other in the later stage gradually. The regression equations of accumulation and disappearance for the specific activity of total tritium in the water, soil and rice were given by analyzing the obtained data with exponential regression method. The analysis results of variance showed that each regression equation could describe the behavior of accumulation and disappearance of HTO in the rice water-soil ecosystems preferably.
    Content and extractability of heavy metals in cultivated soil in Fujian Province
    ZHANG Jinbiao, HUANG Weinan, CHEN Yusen, SU Nianhua, WANG Guo
    2003, (2):  273-276. 
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    The total and extractable contents of 7 heavy metals in cultivated soil in Fujian Province were determined. Statistical results indicated that the cultivated soil in Fujian Province was polluted by heavy metals, but different heavy metals caused different pollution levels. The extractable contents of heavy metals accounted for 10.0 to 52.2 % of total contents, varying with different heavy metals. There was a significantly positive correlation between total and extractable content of Cu, Zn, Cd, Pb, and Ni. Besides, Zn, Cd, Pb and As had a significantly positive correlation to each other, while only Zn had a significantly positive correlation to Ni, and Cu and Hg were not significantly correlated to any of other heavy metals.
    Purification of eutrophicated water body by Vetiveria zizanioids
    SI Youbin, BAO Junjie, CAO Deju, PENG Jun, Yang Qiang
    2003, (2):  277-279. 
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    Studies on the purification efficiency of eutrophicated water body by Vetiveria Zizanioids on floating beds showed that V. zizanioids had a great ability to remove TN, NH4+-N, TP, PO43-, COD, and BOD, and had a significant effect on improving water quality. It was proved that V.zizanioids could be used to purify the eutrophicated water body.
    Ecological footprint calculation and development capacity analysis of China in1999
    XU Zhongmin, ZHANG Zhiqiang, CHENG Guodong, CHEN Dongjing
    2003, (2):  280-285. 
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    The ecological footprint method put forward and improved by William Rees and Mathis Wackernagel presents a methodologically simple but integrated framework for national natural capital accounting, which is capable of measuring the impact of Human's consumption on ecosystem. Based on the ecological footprint theory and calculation method, a flow network analysis method was introduced to illuminate the structure of complex ecological economic system, and the relationship among ecological footprint, diversity and development capacity was analyzed.In this paper, the ecological footprints of China and its provinces was calculated and compared with the national and local ecological carrying capacity. The results showed that the ecological footprints of China and most of its provinces were beyond the available ecological capacity, and China and its most provinces run 'national or regional ecological deficit'. In case of China, the national ecological deficit was 0.645 hm2 per cap in1999. Secondly, we introduced a flow network analysis method,taking various ecological productive area as note, and adopted Ulanowicz's development capacity formula to analyze the relationship among ecological footprint diversity, development capacity and output. The results demonstrated that Ulanowicz's development capacity was a good predictor of economic system output. At the same time, two distinct ways to change development capacity were produced. Increasing ecological footprint or increasing ecological footprint's diversity would both increase development capacity. Due to the fact that the ecological footprints had already been beyond bio capacities, the only way to increase development capacity was to increase ecological footprint's diversity. The positive relationship between ecological footprint diversity and resources utilization efficiency demonstrated that there was no conflict between increasing ecological footprint's diversity and reducing footprints while not comprising our quality of life.
    Introduction and progress of molecular microbial ecology
    ZHANG Huiwen, ZHANG Qianru, ZHOU Qixing, ZHANG Chenggang
    2003, (2):  286-292. 
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    Molecular microbial ecology is an interdisciplinary field of molecular biological techniques and microbial ecology, which deals with microbial population, diversity, function, and relationships between microorganisms and biotic and abotic environments in microbial ecosystem. All the progress in molecular microbial ecology, especially in microbial diversity, phylogeny and communities of some microoganisms, indicate the renovation in traditional microbial ecology by the introduction of molecular techniques and strategies. This article reviewed the ideation,development, key domains, main methods and the future hot fields in molecular microbial ecology .
    Advances in studies on genetically engineered microorganism ecology
    JIN Suying, ZHANG Jiazhi, WANG Yanhong, MENG Shuying
    2003, (2):  293-295. 
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    Genetically engineered microorganism ecology has been one of main research contents in microorganism molecular ecology. Along with the introduction of molecular marker and molecular biology,traditional microorganism ecology has been developed; therefore, it is possible to study the relationship between GEM and environment, environmental microorganism under molecular level. The GEM ecology has become a new and intersection borderline discipline, related to molecular biology, microbiology, ecology and so on. Moreover, it brought forward that the prosecution of the research on the transgenic organism ecology and the risk assessment, and the foundation of checking means and valuating standard that adapt to the situation of China could help to the development of GEM ecology in China.
    Advances in vermiculture and inhibition of vermicompost to soil-borne disease
    HU Yanxia, SUN Zhenjun, CHENG Wenling
    2003, (2):  296-300. 
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    The transformation of organic wastes into useful resources by vermiculture has been a biological technology for ages, and obtained a new development in1970s. This paper mainly reviewed the methods of vermiculture, the physical and chemical aspects of vermicompost, and the comprehensive utilization of vermicompost, and emphasized the inhibition of vermicompost to soil borne disease. Although the mechanisms of inhibition have not been fully understood, the application has great potentiality. The disease inhibition is related with the microflora, especially the large number antagonisms enriched in vermicompost.
    On planning methods of sustainable eco-environmental management in mining areas
    LIU Ping, TANG Wanjin
    2003, (2):  301-304. 
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    Studies on the theory and methodology of ecological planning could provide material guide and technical support for sustainable development in mining areas. As one of the most important section of ecological planning in mining areas, sustainable eco environmental managing planning run through the whole producing course. On the basis of sustainable eco environmental construction and management, the framework of eco environmental management system of mining areas was established in this paper. The material methods for confirming the indexes of eco environmental management,recognizing the factory of eco environment and making the decision of eco environmental managing project were also provided.
    Effect of inorganic nitrogen on CH4 oxidation in soils
    WANG Zhiping, HU Chunsheng, YANG Jurong
    2003, (2):  305-309. 
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    The effects of N inputs,including N fertilizer applications and atmospheric Ndepositions, on CH4 oxidation by soils were determined by CH4 oxidizing bacteria, N inputs and soil factors. These effects were inhibitory or stimulative, but inhibition was more popular than stimulation, and the inhibition of NH4+ was more popular than that of NO3-. Wealthy experiments in different soils and climate regions are required to monitor and evaluate how N inputs influence CH4 oxidation in soils. Generally, CH4 oxidation in soils following N inputs showed multiple inhibition patterns, i.e., immediate or direct inhibition, delayed inhibition, and absence of inhibition. Some researchers explained the inhibition mechanism through using competition between CH4 and NH4+ for the same enzyme sites, elevated threshold, salt effect and ion exchange, and N turnover rate and N concentration. However, the inhibitory mechanism is still unclear. Therefore, inhibitory mechanism is one of the main research concerns in future.
    Advances of studies on the effects of plant volatiles on insect behavior
    YAN Shanchun, ZHANG Dandan, CHI Defu
    2003, (2):  310-313. 
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    Plant volatiles show different effects on insect behaviors, which included luring, repelling and killing. After damaged by phytophagous insects, some host plants could send volatiles luring natural enemies as an indirect defense. Asummarize on the new advances of plant volatiles was given. The role of plant volatiles in integrated pest management in future was also discussed.
    Discussion on several indices assessing landscape dispersion
    JIN Weibin, HU Bingmin
    2003, (2):  314-316. 
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    Several indices assessing landscape dispersion, such as isolation, type divergence and nearest neighbor index, were compared. Different indices could reflect different aspects of landscape dispersion. Dispersion index was suggested to assess the dispersion more comprehensively. All the indices were computed to study the landscape dispersion in a valley basin, and the results showed that dispersion index was better to synthesize information and to be in line with practice than others.
    Preliminary study on ecological footprint in Bashang region of Zhangjiakou city
    HU Mengchun, ZHANG Yongchun, MIAO Xubo, SHEN Weishou, MA Ronghua
    2003, (2):  317-320. 
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    The ecological footprint and ecological carrying capacity in Bashang region of Zhangjiakou city were calculated with the statistical data of the region in1999. Based on calculation, the balance between ecological footprint and ecological carrying capacity was analyzed, and the threshold values of the ecological carrying capacity and population capacity of the region at the current production level were determined. Strategies on reducing ecological deficit in this region were also brought forward.