Table of Content

18 May 2006, Volume 17 Issue 05

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Articles

Soil carbon cycle of Pinus tabulaeformis forest in Huoditang forest region of Qinling Mountains

KANG Bowen;LIU Jianjun;DANG Kunliang;CHEN Haibin

2006, 17(05):  759-764 . 

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With soil carbon cycle compartment model,this paper studied the carbon storage and flux of each carbon compartment of soil under Pinus tabulaeformis,a main forest type in the Huoditang forest region of Qinling Mountain.The results showed that the storage of soil organic carbon was 146.071 t·hm^-2，with 130.366 t·hm^-2 in mineral soil layer and 12.626 t·hm^-2 in litter layer.The storage was lower than the average value of forest soils in China and of oak Sharptooth forest soil in Huoditang,but higher than that of the soils under temperate coniferous forest and tropical forest.The annual carbon input into litter layer was 5.939 t·hm^-2,with 56.9% from above-ground litter and 43.1% from underground dead roots,while that into mineral soil layer via humic acid was 2.034 t·hm^-2.The annual amount of carbon released from the respiration of P.tabulaeformis forest soil system was 14.012 t·hm^-2,with litter layer,mineral soil layer,dead root system,and live root system occupied 15.7%,14.5%,11.7% and 58.1%,respectively.

Effects of Robinia pseudoacacia roots on deep soil moisture status.

CAO Yang^1,2_;ZHAO Zhong¹;QU Mei^1_;CHENG Xiangrong²;WANG Dihai¹

2006, 17(05):  765-768 . 

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he study on the root distribution characters of Robinia pseudoacacia and soil moisture status in the Loess Plateau showed that on shady slope,there was no obvious difference in the horizontal distribution of R.pseudoacacia fine roots within 2.0 m from the stem,and the maximal distribution depth of the roots could reach 2.0 m.In sunny slope,the vertical distribution of the roots within 0.5 m from the stem could also reach that depth.The root amount in shady slope was larger than that in sunny slope,and the affected depth of R.pseudoacacia roots on soil moisture status reached 3.3 m in shady slope,while 2.7 m in sunny slope.

Impact of soil cadmium contamination on chlorophyll fluorescence characters and biomass accumulation of four broad-leaved tree species seedlings

CAO Ling;WANG Qingcheng;CUI Donghai

2006, 17(05):  769-772 . 

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In a greenhouse pot experiment,a gradient of soil Cd concentration was established by adding 0,50,100 and 200 mg CdCl₂·kg^-1 air-dried soil,and the seedlings of one-year-old Rosa davurica,Philadelphus schrenkii,Acer mandshurica and Lonicera maackii were transplanted.The measurement of the seedlings’ chlorophyll fluorescence parameters and biomass accumulation after 70 days of transplanting showed that with increasing soil Cd content,all the test tree species had a decrease of F_v/F_m,ΦPSⅡ,qP and biomass,but an increase of qN.A.mandshurica had the greatest responses,followed by P.schrenkii and L.maackii,and R.davurica.The tolerance of these tree species to soil Cd contamination followed the order of R.davurica > P.schrenkii and L.maackii > A.mandshurica.

Responses of microbes in rhizospheric soil of Abies faxoniana to elevated atmospheric CO₂ concentration and temperature

XIAO Ling¹;WANG Kaiyun^1,2;ZHANG Yuanbin¹;WU Fuzhong¹;LU Yejiang¹

2006, 17(05):  773-777 . 

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With independent and top-enclosed chamber system,this paper studied the responses of culturable bacteria,fungi,and actinomycetes in rhizospheric soil of Abies faxoniana sapling to elevated atmospheric CO₂ concentration (ambient＋350(±25)μmol·mol^-1,EC),temperature (ambient＋2.2(±0.5)℃; ET),and their combination (ECT) under highfrigid conditions of West Sichuan Province.The results showed that in comparing with the control,treatments EC and ET increased the number of rhizospheric bacteria by 35%,164% and 312%,and 30%,115% and 209% in June,August and October,respectively,but had little effects on the numbers of rhizospheric actinomycetes and fungi.In treatment ECT,the numbers of rhizospheric actinomycetes and fungi increased by 49%,50% and 96%,and 151%,57% and 48% in June,August and October,respectively,while that of rhizospheric bacteria had little variation.EC,ET and ECT had significant effects on the total number of rhizospheric microbes,with the R/S being 1.93,1.27 and 1.46,respectively,but had little effects on non-rhizospheric microbes.

Effects of mulching and intercropping on temporal-spatial variation of soil temperature in tea plantation in subtropical hilly region

PENG Wanxia^1,2;SONG Tongqing¹;XIAO Runlin¹;YANG Zhijian²;WANG Jiurong¹;LI Shenghua³;XIA Yanjun^1,2

2006, 17(05):  778-782 . 

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The study of four years straw mulching and white clover intercropping in a tea plantation in subtropical hilly region showed that the soil temperature in the plantation presented a distinct dynamic temporal-spatial variation and hysteresis,which was greatly accorded with the fittest temperature of tea growth.Straw mulching and white clover intercropping altered the nature of soil thermal exchanging layer (soil surface),decreased daily temperature difference,enhanced the temperature stability in the same soil layer,and had duplex effects of lowering temperature when it went up and increasing and keeping temperature when it went down.The effectiveness was in the order of white clover intercropping >strawmulching>control,13:00>19:00>7:00,and lowering temperature>increasing and keeping temperature,and decreased with soil depth.Straw mulching and white clover intercropping adjusted the switching point of the temporal-spatial variation of soil temperature,and evidently decreased the emergence of harmful high temperature.During the period of continual high temperature,these measures markedly lowered soil temperature,and effectively shortened the duration of this period.

Responses of Changium smyrnioides seedlings survival and growth to light intensity

SHENG Haiyan¹;LI Weicheng²;GE Ying³

2006, 17(05):  783-788 . 

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Changium smyrnioides,a monotypic species in Umbellaceae,can only be found in Yangtze Rive basin in China,and its seedlings are rare in natural habitats. The study on the effects of light intensity on C.smyrnioides seedlings survival and growth showed that the seedlings had the highest survival rate under higher light intensity (65% of direct sun light) but the lowest one under 25% of direct sun light,indicating that medium light intensity was propitious to seedlings establishment.The seedlings growth of C.smyrnioides was also the best under 65% of direct sun light,showing the maximum values of growth rate,total leaf area,leaf biomass,root biomass,and total biomass.Low temperature pregermination gave five times higher seedlings biomass than normal germination,and helped the seedlings enduring disadvantageous environment,which provided a new approach to planting and protecting C.Smyrnioides.

Spatial heterogeneity of soil moisture in Shapotou sand-fixing artificial vegetation area

MA Fengyun¹;LI Xinrong²;ZHANG Jingguang²;LI Aixia²

2006, 17(05):  789-795 . 

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To explore the characteristics of soil moisture heterogeneity in sand-fixing artificial vegetation area is of significance in vegetation recovery and environment control in arid regions.With the methods of traditional statistics and geo-statistics,this paper studied the heterogeneity of soil moisture in the layers from 0 to 200 cm in depth in Shapotou sand-fixing vegetation area.The results showed that the variation of soil moisture in layers of 160～180 and 180～200 cm was relatively larger,with the variation coefficient being 072 and 0.73,respectively,and the next was in top layer (0～5 cm ),with a variation coefficient of 0.66.Semi-variance analysis showed that the autocorrelation of soil moisture spatial heterogeneity in total spatial heterogeneity was high,ranging from 87.7% to 99.9%.The scale of spatial heterogeneity in different soil layers was different,with the minimum in 60～80 cm layer and the maximum in 20～40 cm layer,but no regular changes being observed from surface to deep layers.The colorful contour maps of Kriging interpolation indicated that the variation of soil moisture was larger in 0 ～140 cm layer than in 140～200 cm layer.The correlation between semi-variance and distance in four directions of 0°,45°,90° and 135° was weak, suggesting that the variation of soil moisture was independent, random, and homogeneous.

Protective effects and their mechanisms of cobalt on soybean seedling’s leaf under drought stress.

JIAO Jian;LI Chaozhou;HUANG Gaobao

2006, 17(05):  796-800 . 

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This paper studied the effects of cobalt on the polyamine content,reactive oxygen level,anti-oxidative enzyme activity,and cell membrane permeability of soybean seedling’s leaf under drought stress,and discussed the mechanisms of these effects.The results showed that under drought stress,cobalt at its concentration of 30 μmol ·L^-1 could significantly inhibit the production of ethylene.This concentration of cobalt had no significant effects on the contents of MDA and chlorophyll when the drought stress lasted 0～12 days,but significantly restrained the increase of reactive oxygen level,hampered the decline of putrescine,spermidine and spermine contents and anti-oxidative enzyme activities,and thus,inhibited the accumulation of MDA and alleviated the reduction of chlorophyll content when the stress lasted 15~21 days.It could be concluded that when soybean seedling’s leaf was deeply stressed and damaged under drought stress,cobalt could alleviate the decline of polyamine content and anti-oxidative enzyme activity,and hence,alleviate the increment of reactive oxygen level and cell membrane’s damage degree through inhibiting the production of ethylene,and exerted its protective effects on the soybean seedling’s leaf under drought stress.

Effects of irradiance on boron requirement of Phaseolus aureus cutting for its adventitious root development

ZHAO Ruifen;JIAO Xiaoyan;YANG Zhiping;WANG Jinsong;NIU Shangen

2006, 17(05):  801-804 . 

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This paper studied the boron requirement of Phaseolus aureus cutting for its adventitious root development under different photosynthetic active radiation (PAR).The results showed that exogenous boron supply was necessary for the adventitious root development of the cutting under 10 days of PAR at 50 or 100 μmol·m^-2·s^-1,but unnecessary under 6 days of this irradiance and followed by 4 days of darkness.Exogenous boron supply was also necessary for the rooting under 6 days of PAR at 180 μmol·m^-2·s-¹ and followed by 4 days of darkness.When the PAR at 100 μmol·m^-2·s^-1 was employed for 10 days,the amount of soluble boron in each hypocotyl of the cutting was only half of that under 6 days of this irradiance and followed by 4 days of darkness,which might be the reason of the necessity of exogenous boron supply for the rooting under 10 days of PAR at 100 μmol·m^-2·s^-1.

Effects of different furrow irrigation modes on grape growth and water use in oasis region

DU Taisheng¹;KANG Shaozhong¹;ZHANG Ji²;YANG Xiuying²

2006, 17(05):  805-810 . 

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In this paper,a field experiment was conducted in the oasis region of Hexi Corridor,Gansu Province to study the effects of alternate partial root zone furrow irrigation (AFI) and conventional furrow irrigation (CFI) on grape growth and water use under mulching and no mulching.The results indicated that AFI,either mulching or no mulching,could alternately keep a part of root zone drying and another part of it wetting,which induced the compensative growth of grape.Under AFI,more leaf stomas closed.The photosynthesis rate was less affected,but the transpiration rate decreased obviously,and the water use efficiency increased.It was suggested that AFI,especially combined with film mulching,could regulate the behaviors of leaf stoma,and promote grape growth and water use,being an effective approach in cultivating grape in the field.

Simulation of greenhouse tomato dry matter partitioning and yield prediction

NI Jiheng¹;LUO Weihong^1,2;LI Yongxiu¹;DAI Jianfeng¹;JIN Liang¹;XU Guobin¹;CHEN Yongshan¹;CHEN Chunhong²

2006, 17(05):  811-816 . 

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Based on the relationships between dry matter partitioning index,harvest index,and product of thermal effectiveness and PAR,a simulation model for greenhouse tomato dry matter partitioning and yield prediction was built,and validated by independent experimental data of different cultivars,substrates and locations.The coefficient of determination (R²) between simulated and measured shoot,root,stem,leaf and fruit dry matter weight based on 1∶1 line was 0.95,0.57,0.82,0.79 and 0.93,the root mean squared error (RMSE) between them was 647.0,78.1,279.0,496.9 and 381.8 kg·hm^-2,and the R² and RMSE between predicted and measured yield based on 1∶1 line were 0.88 and 5 828.5 kg·hm^-2,respectively.Compared to ‘sourcesink’ theory,the model developed in this study could give satisfactory prediction of the dry weight of leaf,stem,fruit and yield,with fewer parameters that could be easily obtained in practice.

Changes of crop yield and soil fertility under long-term fertilization and nutrients-recycling and reutilization on a black soil:Ⅳ.Soil organic carbon and its fractions

ZHAO Lijuan^1,2,3;WHAN Xiaozeng^1,2;WANG Shouyu^1,2;LIU Hongxiang^1,2;LI Haibo^1,2,3;MIAO Shujie^1,2,3;ANG Feng^1,2,3

2006, 17(05):  817-821 . 

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A longterm experiment was conducted on a black soil of Northeast China to study the effects of applying chemical fertilizers and recycled organic manure (ROM) on the changes of soil organic carbon and its fractions.The results showed that from 1985 to 2004,soil total organic carbon (TOC) decreased by 7.83% in control,4.56% in N application,1.61% in N+P application,and 5.56% in ROM application,but increased by 0.33% in N+P+K application.Comparing with single application of ROM,its application with chemical fertilizers, i.e.,N+ROM,N+P+ROM,and N+P+K+ROM,increased the TOC concentration by 0.35%,1.05% and 0.64%,respectively.The readily oxidized carbon (ROC) in fertilization treatments was increased by 8.64%～28.4%,and the increment was higher in treatments of chemical fertilizers plus ROM than in treatments of chemical fertilizers.The ROC was significantly correlated with soil TOC (Y=14.192 X+23.9,R²=0.802) and stalk yields (Y=19032 X-7950.6, R²=0.759).Light fraction organic carbon (LF-C) had the same trends with ROC.After 20 years fertilization,the organic carbon in soil humic acid and fulvic acid was decreased by 1.64%～26.23% and 2.33%~28.68%,respectively,but in treatments of chemical fertilizers plus ROM,the decreasing trend was slowed down.

Effects of abscisic acid on photosynthetic characteristics and antioxidant enzyme activities of wheat seedlings exposed to UV-C

LI Xuemei^1,2;ZHANG Lihong²;HE Xingyuan²;WANG Lanlan¹;CHEN Qiang¹

2006, 17(05):  822-826 . 

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This paper studied the effects of short and long term abscisic acid (ABA) treatments on the CO₂ assimilation (P_n),carboxylation efficiency(CE),response of P_n to CO₂,and antioxidant enzyme activities of wheat seedlings exposed to UV-C.The results showed that under no UV-C,short-and long term ABA treatments increased P_n by 14.69% and 20.46%,and decreased stomatal conductance (G_s) by 14.74% and 17.31%,respectively,compared to the control,while no effects were observed on intercellular CO₂ concentration (C_i) and CE.Under UV-C,the P_n,CE,G_s and C_i decreased,with the least decrease in long term ABA treatment,less in short term ABA treatment,and the most in control.ABA could increase the response of P_n to CO₂,while UV-C inhibited it.In ABA treatments,antioxidant enzyme activities were enhanced,while MDA content was decreased.Under UV-C,CAT activity increased first,reached its maximum after 1 h,and decreased then.The activities of SOD and POD in ABA treatments increased first and decreased then,with the greater increase in long term ABA treatment than in short term ABA treatment,while those in the control decreased.It was suggested that through enhancing P_n and antioxidant enzyme activities,ABA could enhance the resistance of wheat to UV-C,and long term ABA treatment had better effects than short term ABA treatment.

Effects of specific microbial biocides on N transformation in soil with glucose amendment

WANG Ge^1,2;HE Hongbo²;ZHANG Xudong²;LI Jiandong¹;HAN Lin^1,2;WANG Jingkuan¹

2006, 17(05):  827-830 . 

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In an incubation test of soil with glucose amendment,two kinds of nitrogenous fertilizer and three kinds of specific microbial biocides were applied,and the contents of soil NH₄⁺-N,NO₃^--N,glucosamine and muramic acid were measured to differentiate the relative contribution and timing characteristics of soil microbes in nitrogen immobilization.The results showed that penicillin and streptomycin decreased the transformation rate of NH₄⁺-N markedly,with more significant effects than actidione.The amount ratio of glucosamine to muramic acid after applying penicillin and streptomycin rapidly increased first,and tended to equilibrium then.With the application of actidione,the transformation rate of NO₃^--N decreased continuously,and the synthesis of glucosamine was inhibited,while penicillin and streptomycin had no significant effects on them.At the early stage of incubation,bacteria could rapidly immobilize both NH₄⁺-N and ,NO₃^--N with NH₄⁺-N preferred,while at the later stage of incubation,fungi were the dominant contributor to nitrogen transformation,and had much stronger ability of utilizing NO₃^--N than bacteria.

Effects of longterm localized fertilization on soil humus combining form in sheltered vegetable field

ZHANG Hongling¹;LIANG Chenghua¹;DU Liyu¹;CHEN Xinzhi¹;LI Jibai²

2006, 17(05):  831-834 . 

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The study showed that on a sheltered vegetable field, a long-term application of organic plus chemical fertilizers induced a higher content of loosely combined soil humus than applying chemical fertilizers alone, while there was no significant difference in firmly combined humus content among different fertilization treatments. More tightly combined humus was observed in organic fertilizer treatments than in chemical fertilizer treatments, and the highest content (11.53 g·kg^-1) was in the treatment of organic fertilizer plus chemical NPK. The ratio of loosely/tightly combined humus tended to decrease after a longterm application of organic fertilizer, being the lowest (1.10) in the treatment of organic fertilizer plus chemical NPK.

Photosynthetic characters and fluorescence parameters of different grape stocks under water stress

QI Wei,TAN Hao,ZHAI Heng

2006, 17(05):  835-838 . 

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The study showed that water stress decreased the net photosynthetic rate (P_n),stomatal conductance (G_s),T_r transpiration rate (T_r),maximum fluorescence (F_m),ratio of variable to maximum fluorescence (F_v/F_m),and actual activities of PSⅡ (ФPSⅡ),but increased the minimal fluorescence (F_o).The alterations of test parameters differed with grape stocks.Under adequate water supply and mild water stress,the P_n of 3309C was higher than that of 1103P and 420A,while the chlorophyll fluorescence parameters of these three stocks changed a little.Under moderate water stress,the P_n of 1103P was higher than that of 420A and 3309C,the F_o of 3309C increased by 17.1% while F_v/F_mdecreased by 8.5%,and the F_o of 1103P increased by 6.8% while F_v/F_m decreased by 5.8%.Under severe water stress,the P_n of 1103P was the highest (5.6 μmol·m^-2·s^-1),which was 24% higher than that of 3309C,and the water use efficiency of 1103P was about 1.95 times as high as that of 3309C.The F_o of 3309C increased by 36.2% while F_v/F_m decreased by 20.1%,and the F_o of 1103P increased by 9.9% while F_v/F_mdecreased by 10.2%.It was implied that there was a close correlation between drought-resistance and the alteration of photosynthetic characters and chlorophyll fluorescence parameters,of which,the correlation index of F_v/F_m and P_n was the highest (r=0.9883).

Relationships between row crop evapotranspiration and two sources-energy partition and exchange under non-water stress condition

YU Chan¹;Chaolunbagen¹;GAO Ruizhong¹;CHAI Jianhua²

2006, 17(05):  839-844 . 

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crop coefficient approach presented in FAO-56,this paper estimated the available energy partitioned into two sources,canopy and soil surface (A_c and A_s),and the latent and sensible heat fluxes,λE_c,λE_s,H_c and H_s.The results showed that under non-water stress condition,the interaction between H_c and λE_c made canopy absorbed a micro-advection to enhance transpiration expressed by latent heat flux,with the value of (λE_cⁱ-A_cⁱ).The greatest enhancement of transpiration occurred at the crop development stage with leaf area index between 0.6 and 2.4,and the average of the enhancement was 4.32 MJ·m^-2·d^-1.Soil evaporation was in progress with a rate below the available energy of soil,due to the interaction between H_c and λE_c under non-water stress condition,except a few days immediately after heavy rain.The evaporation rate depended on the percentage of soil available energy dissipated as latent heat flux.The average value of minimum percentage,11.5%,occurred at mid-season stage,while that of maximum percentages,51.9%,occurred at initial stage.Latent heat fluxes were the important components of energy exchange during the process of evapotranspiration.The available energy dissipated as latent heat fluxes of the two sources during crop development,mid-season,and late season stages accounted for over 83% of the total energy.

Allelopathy of aqueous extract from Ligularia virgaurea,a dominant weed in psychro-grassland,on pasture plants

MA Ruijun^1,2;WANG Mingli²;ZHAO Kun³;GUO Shoujun¹;ZHAO Qingfang²;SUN Kun²

2006, 17(05):  845-850 . 

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Ligularia virgaurea is a noxious weed widely distributed in the alpine grassland of east Qinghai-Tibet Plateau of China.This paper studied the allelopathy of its aqueous extract on the pasture plants Festuca sinensis,Bromus magnus,Elymus nutans,Poa annua,and F. ovina in the region.The mean response index (RI) values of the pasture plants were calculated,and used to quantitatively assess the allelopathic sensitivity of the receptors at three levels,i.e.,growth items,development stages,and species.Corresponding values of the weed were also treated in similar way to assess the allelopathic potential of the donor.The results showed that the allelopathic sensitivity was in the order of P.annua>B.magnus>F.sinensis>F.ovina>E.nutans.Both the seed germination and the seedling growth of test pasture plants were inhibited at species level,suggesting that rain eluviation was one of the means by which the weed released allelochemicals.The aqueous extracts from L.virgaurea root and leaf had a significant inhibitory effect at species level,and the effect of root extract was stronger than that of leaf extract,suggesting the competition among species on the underground resources in natural grassland.Allelopathy played an important role in L.virgaurea invasion,and might be responsible to the formation of mono-dominant community and the degeneration of grassland.

Effects of light intensity on resveratrol and polydatin production in Rumex gmelini root

WANG Zhenyue¹;CUI Honghua²;WANG Zongquan¹;LI Ruiming¹;KANG Yihua¹

2006, 17(05):  851-854 . 

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he study under controlled conditions showed that short-term shading resulted in the increase of resveratrol and polydatin contents in Rumex gmelini root,while long-term shading led to the decrease of them.The increase and decrease were more obvious with increasing shading degree and time.The production of resveratrol reached the maximum in August,while that of polydatin was in September.Shading had a negative effect on the resveratrol and polydatin accumulation in R.gmelini root,but severe shading at the late growth period of R.gmelini increased the production of resveratrol and polydatin.

Long-term effects of different planting proportion on forest landscape in Great Hing’anling Mountains after the catastrophic fire in 1987

WANG Xugao^1,2;LI Xiuzhen¹;HE Hongshi^1,3;XIE Fuju^1,2

2006, 17(05):  855-861 . 

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With LANDIS model,this paper simulated the long-term dynamics of 100% larch (P₁),70% larch and 30% Mongolian Scotch pine (P₂),50% larch and 50% Mongolian Scotch pine (P₃),30% larch and 70% Mongolian Scotch pine (P₄),and 100% Mongolian Scotch pine (P₅) in the Tuqiang Forest Bureau at the northern slope of Great Hing’anling Mountains after the catastrophic fire in 1987,taking the forest under natural regeneration as the reference.The results showed that at the early,medium,and late stages of succession,different planting proportion all had significant effects on the abundance of larch,Mongolian Scotch pine,and white birch.The abundance of larch increased with time,while that of Mongolian Scotch pine was in a converse way.Larch and Mongolian Scotch pine had an increased abundance with their increasing planting proportion,but the abundance of white birch was higher under natural regeneration than under different proportions of planting.The abundance of white birch was positively affected by the planting proportions of larch and Mongolian Scotch pine.As for the total abundance of larch and Mongolian Scotch pine,it had no significant difference under P₂,P₃ and P₄,but was higher than that under P₁ and P₅,indicating that individual-species planting should not be used in the forest landscape.

Land use and land cover changes and driving forces in the upper reach of Minjiang River

ZHAO Yonghua^1,2,3;HE Xingyuan¹;HU Yuanman¹;CHANG Yu¹

2006, 17(05):  862-866 . 

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The upper reach of Minjiang River is the representative of mountainous area in Southwest China in the aspects of natural environment,ecosystem structure,economic development,and social culture.The characteristics of the dynamic changes of its land use and land cover stood for the common questions occurred in the land resources and usage of this area.Woodland and grassland are the main types of land use and land cover,and many changes in land use/cover types happened from 1974 to 2000.Among forestland,shrub land,economic forestland,grassland,cropland and resident land,changes mainly happened between woodland and grassland,and all occurred bilaterally.The area of forestland changed mostly and kept decreasing from 1974 to 2000,while that of other land types increased.The changes of land use and land cover happened between 1974 and 1986 were larger than those happened between 1986 and 2000.Population and economy were the main driving factors for the changes of land use and land cover in the upper reach of Minjiang River.Since the programs of Natural Forest Protection and Withdrawing Cropland to Woodland and Grassland carried into execution,the land use and land cover have changed rationally.

heoretical analysis of ecological diversity models and their application in Fukang of Xinjiang Uygur Autonomous Region

YUE Tianxiang¹;MA Shengnan^1,2;WU Shixin³;ZHAN Jinyan¹

2006, 17(05):  867-872 . 

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Ecological diversity refers to a combination of the richness and evenness of an investigation object.Based on this,the widely used model,Shannon model,and a recently developed model,Scaling ecological diversity model,were theoretically analyzed in this paper.It was indicated that Shannon model had many limitations,e.g.,it could be available only when the number of each type of investigation object was more than 100,did not include any information of scale,and could not express the richness of diversity.In other words,Shannon model could only express the evenness of diversity.A case-study in Fukang of Xinjiang Uygur Autonomous Region showed that the richness and Shannon evenness were always resolution-dependent,while the ecotope diversity calculated by Scaling ecological diversity model was resolution-independent when the spatial resolution ranged from 30 m×30 m to 150 m×150 m,and strictly increased when the spatial resolution ranged from 150 m×150 m to 480 m×480 m.

Temporal-spatial characteristics of land use in Xinjian County,Jiangxi Province

CHEN Wenbo^1,2;ZHAO Xiaofan¹;CUI Lijuan³

2006, 17(05):  873-877 . 

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With the support of RS and GIS,and using a series of indices in characterizing the dynamics of land use,this paper studied the temporal-spatial characteristics of land use in Xinjian County,Jiangxi Province,between 1991 and 2000.The results indicated that among single land use types,the area for construction changed mostly.The annual change speed of comprehensive land dynamic index between 1991 and 1995 was 0.5 times higher than that between 1996 and 2000,and the utilization grade in 1991,1996 and 2000 was 243.7,44.1 and 244.9,respectively,being a little higher than the national average grade.The land inflow and outflow in 1996~2000 was lower than that in 1991～1995,and the land use change was from bilateral dynamics to unilateral unbalanced dynamics.

Ecosystem services value of coastal tidal zone in Dongtai City of Jiangsu Province

ZHU Zesheng¹;SUN Ling²

2006, 17(05):  878-882 . 

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The study with satellite remote sensing technique and Costanza method showed that from 1984 to 2003,the total area of various ecosystems in the coastal tidal zone of Dongtai City,Jiangsu Province increased from 108.54 to 171.31 km² or by 57.83% due to natural siltation,of which,the area of natural ecosystem decreased from 60.82 to 21.64 km² or by 64.42%,while that of artificial ecosystem increased from 47.72 to 195.23 km² or by 309.12%. During the same period,the total value of ecosystem services in this zone increased by 76.96%,with natural ecosystem services value dropped from 56.26×10⁴ to 17.19×10⁴ US$ or by 69.45%,while artificial ecosystem services value raised from 40.55×10⁴ to 154.13×10⁴ US$ or by 280.10%. The decrease of natural ecosystem area and the increase of artificial ecosystem area illustrated clearly that the costal tidal ecosystem of this city was being degenerated seriously,and the decline of natural ecosystem services value was resulted from this degradation and the decrease of natural ecosystem area.

Temporal and spatial distribution characteristics and indicator effects of Corbicula fluminea in coastal flat of Changjiang estuary

LI Lina;CHEN Zhenlou;XU Shiyuan;HOU Jing;BI Chunjuan;SHI Guitao

2006, 17(05):  883-886 . 

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Corbicula fluminea is a kind of macrobenthos commonly seen in the coastal wetland ecosystem of Changjiang estuary.This paper studied the temporal and spatial distribution characteristics of its population density and biomass,and analyzed the heavy metals concentrations in its body and in suspended particles and sediments.The results showed that the distribution of C.fluminea was discrepant in different seasons,sampling sites,and even,sampling sections of same sampling site.The population density and biomass of C.fluminea were higher in spring and autumn but lower in summer,and higher in mid-tidal flat than in low and high flats of Chongming.Its annual average population density and biomass was the maximal in Xupu.C.fluminea had definite accumulation ability to copper and zinc,but not to lead and chromium.There was a significant negative correlation between the lead concentrations in C.fluminea and sediments.

Phytoplankton biomass and high frequency of Prorocentrum donghaienseharmful algal bloom in Zhoushan sea area in spring

ZHOU Weihua^1,2;YIN Kedong^1,3;ZHU Dedi⁴

2006, 17(05):  887-893 . 

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Based on the two cruises comprehensive survey on Prorocentrum donghaiense harmful algal bloom (HAB) in Zhoushan sea area in spring 2002 and 2003,this paper studied the distribution pattern of phytoplankton biomass and its relationships with environmental factors.As to the grid station,the mean Chla concentration in surface water layer in spring 2002 was 1.09±1.63 mg·m^-3,ranged from 0.25 to 9.08 mg·m^-3.While in spring 2003,the survey was conducted in the sea area with an isobath of 50 m,where the topography changed suddenly and HAB happened frequently,the mean Chla of surface water layer was 4.21±5.33 mg·m^-3, ranged from 0.44 to 24.32 mg·m^-3.The maximum phytoplankton biomass appeared at the Changjiang Diluted Water frontal zone between 122.5°E and 123°E,where had ample nutrients and good conditions for light penetration in the water column.During the tracking investigation,the Chla concentration in surface water layer in spring 2002 and 2003 was 18.45±11.04 mg·m^-3 and 12.47±8.15 mg·m^-3,respectively.By the tracking investigation of P.donghaiense HAB,four results were found: a) the optimum salinity was between 26 and 30,b) the large scale and long lasted HAB algae was limited by P,c) suitable light condition,nutrients enrichment and water column stabilization were the three important conditions for HAB,and d) the convergent zone in plume front enhanced the gathering of P.donghaiense.

Environmental quality of Guangzhou sea area

JIANG Sheng^1,2;GU Jiguang¹;FENG Jiahe²;FENG Jieping^2,3;YANG Yufeng¹

2006, 17(05):  894-898 . 

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Based on the water quality investigation data from August 2003 to August 2004,and by using single water quality parameter model,integrated water quality index model and eutrophication assessment model,this paper assessed the environmental quality of Guangzhou sea area.The results showed that the key pollutants were dissolved inorganic nitrogen (DIN),dissolved inorganic phosphorus,oil,Cu and Pb,with their annual average concentrations of 1.87 mg·L^-1,0.049 mg·L^-1,0.107 mg·L^-1,6.07 μg·L^-1 and 1.43 μg·L^-1,respectively.Among the pollutants,DIN was the most important one.Its concentration exceeded the fourth standard of sea water quality,and decreased gradually from inner bay to outer bay.Under the effects of Pearl River water flow and land-based pollutants,most part of Guangzhou sea area was seriously polluted,and the annual averages of single parameter pollution index,integrated water quality index,and eutrophication index were 2.22,6.80 and 48.44,respectively,which also decreased gradually from inner bay to outer bay,and from nearshore to offshore.

Consanguinity of sixteen olethreutid moth species in northeast China based on RAPD-PCR analysis

LIU Yanbin;CHI Defu;YAN Shanchun

2006, 17(05):  899-902 . 

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With RAPD-PCR technique,the phylogenetic tree of 16 olethreutid moth species in northeast China was constructed,and their consanguinity was analyzed.The results showed that the clustering of 3 Pandemis species,2 Argyrotaenia species and 4 Archips species on this phylogenetic tree was coincident with their morphological taxology,but that of some other species was not.For example,Clepsis rurinana and C.pallidana were not on the same clade,but on the clade with Pandemis cinnamomeana and Ptycholoma imitartor,respectively.Genetic distance could be an index for genus,and 0.7 was the boundary.The species genetic distance from the same genus was less than 0.7,while that from different genus was more than 0.7.

Effects of transgenic Bt cry1Abrice on collembolan population in paddy field

BAI Yaoyu^1,2;JIANG Mingxing¹;CHENG Jia′an¹;WANG Dun¹

2006, 17(05):  903-906 . 

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To assess the potential ecological risk of transgenic Bt rice to non-target soil organisms in paddy field,transgenic cry1Ab rice KMD1 and KMD2 and their parental control rice line XS11 were planted in experimental fields,and collembolan species and their densities were investigated during grain-filling and post-harvest stages in 2003～2004.By using an arthropod-sucking machine,two collembolan species,Entomobrya griseoolivata and Bourletiella christianseni,were collected from the leaf litter at soil surface during grainfilling stage (September,2003),and the population densities of E.griseoolivata in KMD1 and KMD2 paddy fields were significantly higher than those in XS11 paddy field.With bags contained rice stem-leaf litter and initially placed in the paddy field at harvest time (November,2003),four collembolan species, E.griseoolivata,B.christianseni,Hypogastrura matura and Isotoma monochaeta,were collected during post-harvest stages (April,2004),and the densities of E.griseoolivata and H.matura in KMD1 and KMD2 paddy fields were also significantly higher than those in XS11 paddy field.The biomass loss of KMD1 and KMD2 stem-leaf litter was significantly greater than that of XS11^,s.

Chemical components of Artemisia scoparia volatile oil and its poison activity to mosquito

ZHOU Tian^1,2;GUO Jixun¹;HAN Defu^1,2;XING Fu¹;TIAN Shangyi¹

2006, 17(05):  907-910 . 

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he study showed that Artemisia scoparia contained 0.38% of volatile oil,in which,a total of 38 chemical components were identified,accounting for 87.53% of the substances detected,and 12 kinds of terpenoids compounds were the main components,accounting for 45.04% of the total.The oil had a high and rapid poison activity on Culex pipiens pallens larva and adult.The LC₅₀ value for the larva was 12.5 mg·L^-1 within 2 days,and the mortality of the adult in 24 hours was 70% and 100% when the dosage was 1 and 10 μg·cm^-2.

Effects of insecticides on insect pest-natural enemy community in early rice fields

JIANG Junqi;MIAO Yong;ZOU Yunding;LI Guiting

2006, 17(05):  911-914 . 

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This paper studied the effects of triazophos,shachongshuang,abamectin,and Bt + imidacloprid on the insect pestnatural enemy community in early rice fields in the Yangtze-Huaihe region of Anhui Province.The results showed that all of the test insecticides had significant effects in controlling the growth of major insect pest populations.The average value of insect pestnatural enemy community diversity under effects of triazophos,shachongshuang,abamectin,and Bt+imidacloprid was 1.545,1.562,1.691 and 1.915,respectively,while that in control plot was 1.897.After two weeks of applying insecticides,the plots applied with shachongshuang and abamectin had a similar composition of insect pest-natural enemy community,but the community composition was significantly different between the plots applied with triazophos and Bt + imidacloprid.From the viewpoints of community stability and pest control,Bt + imidacloprid had the best effect,and shachongshuang and abamectin were better than triazophos.

Insect community structure and its dynamics in Chinese prickly ash plantations at different altitudes in Yunnan Province

ZHANG Chengzuo¹;YAO Lizhong¹;LI Qiang¹;LI Zhengyue¹;SONG Jiaxiong²;RUAN Yingzhen²

2006, 17(05):  915-919 . 

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With community character indices and principal component analysis,this paper studied the variation of insect community composition and structure in Chinese prickly ash plantations at four altitudes in Yunnan Province,and analyzed the temporal patterns of the variation and its affecting factors.The results showed that with the increase of altitude,the species diversity,abundance and evenness of the community decreased gradually, while the population number had a certain increase.Such a variation was more obvious with time.The factor dominating the variation was the gradual change of the species and individuals numbers of natural enemy subcommunity to those of pest sub-community.

Isolation and identification of Bacillus cereus strain Jp-A and its capability in phenol degradation

LI Shubin;CHEN Zhenjun;QIU Lili,WU Juan;LAI Zhanpeng

2006, 17(05):  920-924 . 

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In this study,a bacterial strain named as Jp-A was isolated from the activated sludge of a steel factory.Through morphological observation,physiological and biochemical test,and 16srRNA sequence analysis,the strain was identified as Bacillus cereus.Under laboratory condition,the phenol at its initial concentration of 5,10 and 15 mmol·L-1 could be completely degraded by the strain within 16,24 and 32 h,respectively,but the growth of the strain was inhibited when the phenol concentration was 30 mmol·L^-1.The strain could also utilize and degrade other aromatic hydrocarbons, e.g., benzene, toluene, chlorophenol and nitrophenol,as its sole source of carbon and energy. Dioxygenase test indicated that the strain degraded phenol via metapathways.The key enzyme catechol 2,3-dioxygenase was an induced enzyme,which was mainly located on the cell membrane,and adding glucose could inhibit its generation.

Effects of metolachlor on biological activities in celery rhizophere and non-rhizosphere soil

CHEN Bo;XU Dongmei;LIU Guangshen;LIU Weiping

2006, 17(05):  925-928 . 

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The study with rhizobag showed that in celery rhizophere and non rhizosphere soil,metolachlor had a certain inhibitory effect on catalase activity,but stimulated dehydrogenase activity.Generally,the enzyme activities in rhizosphere soil were higher than those in non-rhizosphere soil.After 45 days of metolachlor treatment,the numbers of bacteria and fungi in rhizosphere soil were higher than those in non-rhizosphere soil,and the R/S was 1.76～2.51.The numbers of actinomycetes were relatively stable,and the rhizosphere effect was not significant.The degradation rate of metolachlor in rhizosphere and nonrhizosphere soil was 0.0217 and 0.0176,and the corresponding half-live was 31.9 and 39.4 days,respectively.The degradation of metolachlor was enhanced greatly in rhizosphere soil.

Farmland ecosystem service and its formation mechanism

YIN Fei^1,2;MAO Renzhao²;FU Bojie¹;LIU Guohua¹

2006, 17(05):  929-934 . 

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Farmland ecosystem service has a real and far-reaching effect on the sustainable development of human society,and its study is one of the hotspots in ecology.This paper introduced the connotations of farmland ecosystem service and its valuation methodology,and summarized the present status in researching the formation mechanism of farmland ecosystem service from the aspects of the characteristics of abiotic environment,biota,ecosystem process,and human activity.It’s considered that besides its importance in supplying human society a great number of products,farmland ecosystem is of significance in providing environmental service and maintaining regional ecological safety.Abiotic environment,biota,ecosystem process,and their interactions are the bases of the formation of farmland ecosystem service,and human activity is the primary driving force.It’s imperative to build up an indices system to valuate farmland ecosystem service,and to strengthen the research of the effects of human activity on the farmland ecosystem service formation.

Research advances in depth of edge influence of landscape boundary

LI Liguang^1,2;HE Xingyuan²;LI Xiuzhen²

2006, 17(05):  935-938 . 

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Depth of edge influence of landscape boundary is an important component of landscape boundary research,and also,the hotspot of ecological research at home and abroad.This paper summarized the recent decades’ research advances abroad in depth of edge influence,including quantitative methods,depth of edge influence on abiotic and biotic factors,and affecting factors on depth of edge influence .The studies on depth of edge influence in our country were also discussed,with the development trend prospected.

Responses of enzymes in terrestrial plants to enhanced UV-B radiation

YAO Xiaoqin^1，2;LIU Qing¹

2006, 17(05):  939-942 . 

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With the destruction of ozone layer,ultraviolet-B (UV-B,280～320nm) radiation has being enhanced at the earth’s surface.The energy of UV-B irradiation is far higher than that of visible light,which could be absorbed by biomacromolecules such as protein and nuclei acid.Enzyme is a sort of protein catalyzing the biochemical processes,and its content and activity in plant have strong responses to enhanced UV-B radiation.This paper summarized the research advances in the effects of enhanced UV-B radiation on the key enzymes,mainly including antioxidant enzymes,ribulose-1,5-diphosphoscarboxylase,nitrate reductase and glutamine synthetase in terrestrial plants. Some suggestions for future research in this field were put forward.

Changes of nutrients in soil of transgenic Bt crops

SUN Caixia^1,2;ZHANG Yulan²;MIAO Lu¹;CHEN Lijun²;WU Zhijie²

2006, 17(05):  943-946 . 

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Pot experiment showed that after 30 days of transgenic Bt rice planting and by the end of the growth season of transgenic Bt cotton,the contents of soil total C,total N,alkalihydrolyzable N,and available P and S had no significant difference with the control,which suggested that there was a little disturbance in the cycle and balance of soil nutrients after a short period of transgenic Bt crops planting.

Changes of species diversity in gap gradient of mid-subtropical evergreen broad-leaved forest in Wanmulin Forest

YAN Shujun¹;HONG Wei²;HONG Tao²;WU Chengzhen²

2006, 17(05):  947-950 . 

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Based on the investigation of gap and non-gap stands in the midsubtropical evergreen broad-leaved forest in Wanmulin Nature Reserve of Fujian Province,this paper studied the changes of species diversity in gap gradient and in gaps with different sizes.The results showed that the species richness and diversity decreased gradually from gap center to nongap,ecological dominance was higher in center and lower in edges,and species evenness was in adverse to ecological dominance.The species diversity in all areas of gap was the maximum when the gap size was 200～300 m².

Effects of habitat patch on Lophura nycthemera population

ZHENG Jiawen^1,2;DING Ping¹;XU Xiaojiang¹;XIA Guirong¹

2006, 17(05):  951-953 . 

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To understand the relationships between the distribution of Lophura nycthemera population and the attributes of habitat patch,this paper investigated the population of L.nycthemera in the National Gutian Mountain Natural Reserve and its periphery area in Zhejiang Province from September 1998 to August 1999.The relative population density of L.nycthemera in each patch was determined by transect census with collecting molted feathers,and the effects of vegetation and landscape characteristics on the relative population density and patch occupancy were analyzed by statistic methods.The results showed that the occurrence of L.nycthemera was significantly affected by patch area,total cover,arbor cover,and shrub height.High frequency occurrence of L.nycthemera was observed in the patches with large area,dense total cover,dense arbor cover and high shrub height,and high relative population density was found in large size patches. There was a significant positive linear correlation between relative population density and patch area.