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

Table of Content

    15 October 2004, Volume 15 Issue 10
    Previous Issue    Next Issue
    Applied ecology:Retrospect and prospect
    HE Xingyuan, ZENG Dehui
    2004, (10):  1691-1697. 
    Asbtract ( 0 )  
    Applied ecology is evolved into a principal part of modern ecology that rapidly develops.The major stimulus for the development of applied ecology roots in seeking the solutions for the problems of human populations,resources and environments.Through four decades,the science of applied ecology has been becoming a huge group of disciplines.The future for the applied ecology should concern more with human-influenced and managed ecosystems,and acknowledge humans as the components of ecosystems.Nowadays and in future,the top-priorities in applied ecology should include following fields:sustainable ecosystems and biosphere,ecosystem services and ecological design,ecological assessment of genetically modified organisms,ecology of biological invasions,epidemical ecology,ecological forecasting,ecological process and its control.The authors believe that the comprehensive and active research hotspots coupled some new traits would occur around these fields in foreseeable future.
    Applied ecology:Retrospect and prospect
    HE Xingyuan, ZENG Dehui
    2004, (10):  1691-1697. 
    Asbtract ( 923 )   PDF (680KB) ( 377 )  
    Applied ecology is evolved into a principal part of modern ecology that rapidly develops.The major stimulus for the development of applied ecology roots in seeking the solutions for the problems of human populations,resources and environments.Through four decades,the science of applied ecology has been becoming a huge group of disciplines.The future for the applied ecology should concern more with human-influenced and managed ecosystems,and acknowledge humans as the components of ecosystems.Nowadays and in future,the top-priorities in applied ecology should include following fields:sustainable ecosystems and biosphere,ecosystem services and ecological design,ecological assessment of genetically modified organisms,ecology of biological invasions,epidemical ecology,ecological forecasting,ecological process and its control.The authors believe that the comprehensive and active research hotspots coupled some new traits would occur around these fields in foreseeable future.
    Progress in pollution ecology of soil-plant systems and its expectation
    ZHOU Qixing, SUN Tieheng
    2004, (10):  1698-1702. 
    Asbtract ( 1217 )   PDF (658KB) ( 397 )  
    In order to promote the further healthy development and disciplinary construction of the rising discipline pollution ecology of soil-plant systems and give full play to its more and more important role in solving environmental pollution and food-chain safety at the national level,this paper reviewed the inceptive work and early researches in this scientific area,traced the development of disciplinary definition and connotation,and basic principles and methods,and expounded and prospected the scientific mission,principal research contents and future development of this subject.
    A review on disturbance ecology of forest
    ZHU Jiaojun, LIU Zugen
    2004, (10):  1703-1710. 
    Asbtract ( 1810 )   PDF (1213KB) ( 570 )  
    More than 80% of terrestrial ecosystems have been influenced by natural disasters,human activities and the combination of both natural and human disturbances.Forest ecosystem,as one of the most important terrestrial ecosystems,has also been disturbed without exception.Under the disturbance from natural disasters and human activities,particularly from the unreasonable activities of human beings,forest decline or forest degradation has become more and more severe.For this reason,sustaining or recovering forest service functions is one of the current purposes for managing forest ecosystems.In recent decades,the studies on disturbed ecosystems have been carried out frequently,especially on their ecological processes and their responses to the disturbances.These studies play a very important role in the projects of natural forest conservation and the construction of ecological environment in China.Based on a wide range of literatures collection on forest disturbance research,this paper discussed the fundamental concepts of disturbance ecology,the relationships between forest management and disturbance,and the study contents of forest disturbance ecology.The major research topics of forest disturbance ecology may include:1) the basic characteristics of disturbed forests;2) the processes of natural and human disturbances;3) the responses of forests ecosystem to the disturbances;4) the main ecological processes or the consequential results of disturbed forests,including the change of biodiversity,soil nutrient and water cycle,eco-physiology and carbon cycle,regeneration mechanism of disturbed forests and so on;5) the relationships between disturbances and forest management;and 6) the principles and techniques for the management of disturbed forests.This review may be helpful to the management of disturbed forest ecosystem,and to the projects of natural forest conservation in China.
    Key problems in ecological research on vegetations in Northeast China
    ZOU Chunjing, XU Wenduo
    2004, (10):  1711-1721. 
    Asbtract ( 1340 )   PDF (1859KB) ( 527 )  
    There exist many controversial problems in ecological research on vegetations in Northeast China,in despite of systemic studies for half century.In this paper,some comments were put forward on the recent researches of our concerned problems:1) The zonal distribution pattern of vegetations in Northeast China could be quantificationally explained according to Kira's warmth index (WI),coldness index (CI),and Xu Wenduo's humidity index (HI).2) There exists tundra vegetation in the north of Daxinganling Mountains with 1400 m altitude and above,which is the third tundra in China found by us firstly in 1963,and its WI<15 ℃·month.3) The vegetation boundary between Daxinganling and Xiaoxinganling Mountains is one of the first class lines in vegetation sub-area.It locates in Aihui-Guosonggou-the Nen River,and the WI here is 45 ℃·month.4) In Daxinganling Mountains,the vegetation has significant zonal differentiation.In the south,the vegetation is typical steppe;in the middle,the vegetation is forest-steppe;and in the north,the vegetation is boreal coniferous forest.The HI here are 3.5～5.5,5.5～7.5,and >7.5mm/℃·month,respectively.The broadleaved forest in the east of Daxinganling Mountains is the forest vegetation type in forest-steppe zone.5) In the eastern mountains of Northeast China,Betula ermanii forest is an important composition of vegetation vertical zone in mountains,and it is the timberline.The forest (WI is 20～15 ℃·month) is the zonal vegetation type,whereas the forest (WI >20 ℃·month) is the non-zonal vegetation type.6) In Hunshandake Sandy Land in Inner Mongolia Autonomous Region,spruce forest is the peculiar forest ecosystem type in continent,but which composition the spruce species belongs to is a controversial problem in plant class in China for a long time.It is proved further that it is a new species,namely,Picea mongolica (H.Q.Wu) W.D.Xu,cmb.nov.-Picea meyeri Rehd.et Wils var.mongolica (H.Q.Wu),according to the karyotype analysis and isozyme experiment.
    Effects of climate change on forest succession
    WANG Jijun, PEI Tiefan
    2004, (10):  1722-1730. 
    Asbtract ( 1436 )   PDF (1091KB) ( 620 )  
    Forest regeneration is an important process driven by forest ecological dynamic resources.More and more concern has been given to forest succession issues since the development of forest succession theory during the early twentieth century.Scientific management of forest ecosystem entails the regulations and research models of forest succession.It is of great practical and theoretical significance to restore and reconstruct forest vegetation and to protect natural forest.Disturbances are important factors affecting regeneration structure and ecological processes.They result in temporal and spatial variations of forest ecosystem,and change the efficiencies of resources.In this paper,some concepts about forest succession and disturbances were introduced,and the difficulties of forest succession were proposed.Four classes of models were reviewed:Markov model,GAP model,process-based equilibrium terrestrial biosphere models(BIOME series models),and non-linear model.Subsequently,the effects of climate change on forest succession caused by human activity were discussed.At last,the existing problem and future research directions were proposed.
    Regional ecological construction and mission of landscape ecology
    XIAO Duning, XIE Fuju, WEI Jianbing
    2004, (10):  1731-1736. 
    Asbtract ( 1255 )   PDF (673KB) ( 517 )  
    The eco-construction on regional and landscape scale is the one which can be used to specific landscape and intercrossing ecosystem in specific region including performing scientific administration of ecosystem and optimizing environmental function.Recently,the government has taken a series of significant projects into action,such as national forest protection item,partly forest restoration,and adjustment of water,etc..Enforcing regional eco-construction and maintaining the ecology security of the nation have become the strategic requisition.In various regions,different eco-construction should be applied,for example,performing ecological safeguard measure in ecological sensitive zone,accommodating the ecological load in ecological fragile zone,etc.,which can control the activities of human being,so that,sustainable development can be reached.Facing opportunity and challenge in the development of landscape ecology,we have some key topics:landscape pattern of ecological security,land use and ecological process,landscape changes under human activity stress,quantitative evaluation of the influence on human being activities,evaluation of zonal ecological security and advance warning of ecological risk,and planning and optimizing of model in landscape eco-construction.
    On water saving agriculture and water resource sustainable utilization in Northeastern China
    LIU Zuoxin
    2004, (10):  1737-1742. 
    Asbtract ( 1226 )   PDF (825KB) ( 375 )  
    A strategy of systematic water saving agriculture was proposed based on the analysis of the water resource shortage regime and the agricultural water saving potential under the background of promoting the old industrial bases in Northeastern China.Different pattern areas of water saving agriculture were divided,and integrated water saving technique systems and water saving cultivation models were recommended,according to their agricultural production characteristics and development requirement in the future.The systematic strategy for sustainable utilization of water resource,the necessity of applying project for water saving and regulating rivers and watercourses synthetically,and the trends in water saving research in Northeastern China were discussed.
    Assessing forest ecosystem health IModel,method,and index system
    CHEN Gao, DAI Limin, JI Lanzhu, DENG Hongbing, HAO Zhanqing, WANG Qingli
    2004, (10):  1743-1749. 
    Asbtract ( 1213 )   PDF (943KB) ( 492 )  
    Ecosystem health assessment is one of the main researches and urgent tasks of ecosystem science in 21st century.An operational definition on ecosystem health and an all-sided,simple,easy operational and standard index system,which are the foundation of assessment on ecosystem health,are necessary in obtaining a simple and applicable assessment theory and method of ecosystem health.Taking the Korean pine and broadleaved mixed forest ecosystem as an example,an originally creative idea on ecosystem health was put forward in this paper based on the idea of mode ecosystem set and the idea of forest ecosystem health,together with its assessment.This creative idea can help understand what ecosystem health is.Finally,a formula was deduced based on a new effective health assessment method—health distance (HD),which is the first time to be brought forward in China.At the same time,aiming at it's characteristics by status understanding and material health questions,a health index system of Korean pine and broadleaved mixed forest ecosystem was put forward in this paper,which is a compound ecosystem based on the compound properties of nature,economy and society.It is concrete enough to measure sub-index,so it is the foundation to assess ecosystem health of Korean pine and broadleaved mixed forest in next researches.
    Structure characteristics and health distance assessment of various disturbed communities of Korean pine and broadleaved mixed forest in Changbai Mountains
    DAI Limin, CHEN Gao, DENG Hongbing, JI Lanzhu, HAO Zhanqing, WANG Qingli
    2004, (10):  1750-1754. 
    Asbtract ( 1270 )   PDF (574KB) ( 368 )  
    Through samples investigation,this paper analyzed and classified the community structures of overcutting original forests,secondary birch forests and larch plantation forest under different disturbances.At the same time,some indexes which can reflect the integrity and stability of stand structure were selected.Health Distance (HD) method,a new idea,was attempted to assess ecosystem health of Korean pine and broadleaved mixed forest in Changbai Mountains.The results showed that the health degree was in order of original broadleaved stand (0.14)<structure switched stand (0.23)<structure reserved stand (0.32)<structure destroyed stand (0.33)<heavy disturbed stand (0.44)<secondary birch stand (0.53)<larch plantations (0.68).Hopefully,it will be a helpful reference on the restoration of Korean pine and broadleaved mixed forest and on the regional forestry sustainable development.
    Utilization suitability of forest resources in typical forest zone of Changbai Mountains
    HAO Zhanqing, YU Deyong, XIONG Zaiping, YE Ji
    2004, (10):  1755-1759. 
    Asbtract ( 1253 )   PDF (606KB) ( 342 )  
    Conservation of natural forest does not simply equal to no logging.The Northeast China Forest Region has a logging quota of mature forest as part of natural forest conservation project.How to determine the logging spots rationally and scientifically is very important.Recent scientific theories of forest resources management advocate that the utilization of forest resources should stick to the principle of sustaining use,and pay attention to the ecological function of forest resources.According to the logging standards,RS and GIS techniques can be used to detect the precise location of forest resources and obtain information of forest areas and types,and thus,provide more rational and scientific support for space choice about future utilization of forest resources.In this paper,the Lushuihe Forest Bureau was selected as a typical case in Changbai Mountains Forest Region to assess the utilization conditions of forest resources,and some advices on spatial choice for future management of forest resources in the study area were offered.
    Quantitative methodologies for ecotone determination on north slope of Changbai Mountains
    YU Dapao, TANG Lina, WANG Shaoxian, WANG Shunzhong, DAI Limin
    2004, (10):  1760-1764. 
    Asbtract ( 1274 )   PDF (526KB) ( 310 )  
    Based on the community important values and present-absent data along elevation gradient on the north slope of Changbai Mountains and using moving split-window techniques,the width and location of vegetation ecotone were discussed in this article.The results showed that the methods of Bray-Curtis Percent Dissimilarity(PD)and Squared Euclidean Distance(SED)introduced in the analysis gave the similar results.Among the methods used in the moving split-window analysis,the SED method was the best in showing the variation of ecotone.According to the results of moving split-window techniques analysis,the ecotone between broad leaved-pine forest and dark conifer forest was gradual type,located in 1 120 m a.s.l.,spanned 200 m.;that between dark conifer forest and Betula ermanii forest was sharp type,located in 1 790 m a.s.l.,spanned 50 m;and the timberline was a sharp line,located in 2 000 m,spanned 40 m.
    Effects of soil water regimes on the growth of Quercus mongolica seedlings in Changbai Mountains
    WANG Miao, LI Qiurong, HAO Zhanqing, DONG Baili
    2004, (10):  1765-1770. 
    Asbtract ( 1258 )   PDF (313KB) ( 453 )  
    This paper studied the response of the seedlings of Quercus mongolica,one of the dominant tree species in Changbai Mountains,to the artificially controlled three soil water gradients,including their morphology,biomass and photosynthetic characteristics.The results indicated that various water regimes significantly affected the biomass and its distribution pattern in the leaves,branches and roots,as well as the leaf gas exchange.Under soil water stress,the crown structure changed,and the tree height,groundline diameter,single leaf area,and aboveground and belowground biomass were inhibited.As soil water content decreased,the ratio of belowground and aboveground biomass dry weight significantly increased.Water stress had a negative effect on net photosynthetic rate,CO2 use efficiency and carbon use efficiency.The responses of stomatal conductance,transpiration rate and water use efficiency to water stress were complicated.Only at low soil water content,the stomatal conductance and transpiration rate significantly decreased,while water use efficiency increased.It was demonstrated that Quercus mongolica was the tree species with variable resistance to drought,and the resistance could be improved by long-term soil water stress.
    Dynamics of soil nutrient contents in cutting forestlands of broad-leaved Korean pine forest on Changbai Mountains
    ZHOU Li, DAI Limin, GU Huiyan, YU Dapao
    2004, (10):  1771-1775. 
    Asbtract ( 1302 )   PDF (901KB) ( 390 )  
    A comparative study was made to analyze the dynamics of soil nutrient contents in different cutting forestlands of broad-leaved Korean pine forest on Changbai Mountains.The results showed that soil nutrient contents in different forestlands with different cutting times had obvious differences.With the cutting time going on after logging,soil pH value had the trend of declining firstly and increasing afterwards.The acidity of the topsoil was the highest after cutting for five years,and that of 10～20 cm soil layer was the strongest after cutting for ten years.The organic matter content as well as the total and available contents of nutrients increased at the first 2～5 years,and then declined rapidly,especially for those in topsoils.The cation exchange capacity (CEC),exchangeable Ca and exchangeable Mg had the same trend.Therefore,after forest cutting,artificial planting and regeneration should be carried out in time to resume the vegetation to reduce and prevent soil nutrient loss.
    Nitric oxide,a signaling component of ABA-induced stomatal closure
    WANG Miao, LI Qiurong, FU Shilei, JI Lanzhu, XIAO Dongmei, DONG Baili
    2004, (10):  1776-1780. 
    Asbtract ( 1428 )   PDF (275KB) ( 303 )  
    The present study provided the evidence that exogenous NO and ABA regulated the stomatal movement in poplar leaves.It showed that different levels of SNP and ABA induced the stomatal closure in detached leaves.NO enhanced stomatal closure that induced by ABA.The effect of NO and ABA on stomatal closure was suppressed by c-PTIO,a specific NO scavenger.It was confirmed that NO involved in ABA-mediated stomatal movement.The activities of POD were dramatically inhibited,but those of SOD hardly decreased in different levels of SNP and ABA treatment.However,in vitro experiments indicated that the activities of POD were dramatically inhibited by NO,but not ABA.The results demonstrated that NO mediated ABA-induced stomatal closure of trees,and was a signaling component of ABA-induced stomatal closure.
    A preliminary study on wood-inhabiting fungi on charred wood in Daxinganling forest areas
    YU Changjun, DAI Yucheng, WANG Zhengquan
    2004, (10):  1781-1784. 
    Asbtract ( 1293 )   PDF (1057KB) ( 418 )  
    Study on wood-inhabiting fungi is one of the active fields of mycology during past 30 years in China,and the study mostly focused on natural forest without fire disturbing.Forest fire changes forest ecology dramatically,and the fungi on charred wood are different from those in nature forests without fires.In this paper,we focused on the wood-inhabiting fungi growing on charred wood in Daxinganling forest areas.Seventeen species were reported:Antrodia sp.,Antrodia xantha,Ceriporiopsis mucida,Diplomitoporus lindbladii,Gloeophyllum carbonarium,Gloeophyllum sepiarium,Gloeoporus taxicola,Laurilia sulcata,Oligoporus sericeomollis,Phellinus igniarius,Postia caesia,Postia leucomallella,Postia tephroleuca,Schizopora flavipora,Skeletocutis ochroalba,Skeletocutis vulgaris,and Trichaptum fuscoviolaceum.Among them,eight species caused brown rot,and nine species caused white rot.Based on our field studies,eight species were pioneer fungi in charred wood,four species were common one,and three species were rare or threatened in the studied area.Setting up nature reserve should be the best way to protect the rare or threatened species of wood-inhabiting fungi.
    Distribution patterns of moss species in Shanghai city
    CAO Tong, CHEN Yi, YU Jing, SONG Guoyuan
    2004, (10):  1785-1791. 
    Asbtract ( 1232 )   PDF (1018KB) ( 406 )  
    The mosses on the floor of 22 sites at 20 main parks and 2 chemical plants in Shanghai city were investigated and sampled.Based on 75 recorded moss species and their coverage,Two-way Indicator Species Analysis (TWINSPAN) and Detrended Correspondence Analysis (DCA) were used to analyze their distribution patterns.The results showed that the study sites could be identified as three groups.Group 1 included two chemical plants and two parks at the center of the city,with 23 moss species and the smallest total coverage of 21.29%;group 2 included part of the parks at the center of the city and surrounding areas,with 44 moss species and total coverage of 37.94%;and group 3 mainly included the parks at surrounding areas and suburbs of the city,with 49 moss species and total coverage of 49.66%.The results reflected a certain correlation of the distribution of moss species with different habitats and polluted and disturbed environments in the city.
    A comparative study on soil fauna in native secondary evergreen broad-leaved forest and Chinese fir plantation forests in subtropics
    YAN Shaokui, WANG Silong, HU Yalin, GAO Hong, ZHANG Xiuyong
    2004, (10):  1792-1796. 
    Asbtract ( 1178 )   PDF (563KB) ( 386 )  
    In this study,we investigated the response of soil animal communities to the replacement of native secondary forest by Chinese fir plantation forest and successive rotation of Chinese fir in subtropics.Three adjacent forest stands,i.e.,native secondary evergreen broad-leaved forest stand (control) and Chinese fir plantation stands of first (20 yr) and second (20 yr) rotations were selected for the comparison of soil fauna.All animals were extracted from the floor litter and 0～15 cm soil layer of the stands in Summer,2003 by using Tullgren method,wet funnel method and hand-sorting method.Compared to two Chinese fir plantation forests,the native secondary evergreen broad-leaved forest had a higher abundance and a higher taxonomic diversity of animals in soil and litter,but there were no significant differences in the biomass and productivity of soil fauna between all study stands.The abundance or diversity did not differ significantly between the first rotation and second rotation stands,too.The results supported that vegetation cover might be one of the main forces driving the development of soil animal communities,and the effect of successive rotation of Chinese fir on the development of soil fauna was a slow-running process.
    Landscape pattern change at the upper reaches of Minjiang River and its driving force
    HU Zhibin, HE Xingyuan, JIANG Xiaobo, ZHAO Yonghua, HU Yuanman, CHANG Yu, LI Yuehui, HAN Wenquan, LIU Miao
    2004, (10):  1797-1803. 
    Asbtract ( 1236 )   PDF (1088KB) ( 343 )  
    The upper reaches of Minjiang River is an ecological sensitive and vulnerable area in southwest of China.It is of great significance to the ecological pattern safety in China.In this study,we analyzed the landscape pattern change through the interpretation of TM imageries in 1986,1995 and 2000.The results showed that the matrix landscape in this area was grass landscape.Forest landscape patches were embedded in the grass landscape.The forest landscape area increased from 1986 to 1995 and decreased from 1995 to 2000.However,the number of patches of forest landscape was increasing during all the time.This suggested that the intensity of anthropogenic disturbances including harvesting,forest landscape reclaiming and excessive grazing were persistently increasing from 1986 to 2000.The ecological driving forces of the landscape change in this area were the intensified anthropogenic disturbances as a result of the population boom including the predacious harvesting of forest and excessive grazing.The natural disturbances such as the global climatic change also partly influenced the landscape change in this area.
    Depth of edge influence on agriculture-forestry boundary in arid valley of upper reaches of Minjiang River,China
    LI Liguang, HE Xingyuan, LI Xiuzhen, WEN Qingchun, ZHAO Yonghua, HU Zhibin, CHANG Yu, ZHU Yaping
    2004, (10):  1804-1808. 
    Asbtract ( 1190 )   PDF (281KB) ( 234 )  
    By using moving split-window techniques (MSWT),this study estimated how far the edge effects penetrated the forest and agricultural fields in the arid valley of upper reaches of Minjiang River,southwestern China.Its aim was to provide general information on vegetation along edge to interior gradients in order to assist in interpretation and prediction of biological phenomena associated with agriculture-forestry boundary,and to improve current management practices in such areas.Three types of boundaries (10 transects) were investigated and sampled.The results showed that when the window width reached 6～10,the change of the SED curve on the graph tended to become stable,and one or two peaks occurred.The depth of edge influence was clearly different for different types of boundaries,and could be estimated within 50 m from the edge to interior.The depth of edge influence (DEI) on vegetation diversity almost varied between 12～30 m,mainly depending on the patch type,topography and microclimate,but seldom on slope orientation.Of the 6 forest transects in the three types of boundaries,the DEI was detected only in the forest part transects M2 and M6,but almost detectable in the agricultural part of all transects.MSWT was considered to be a useful tool for characterizing edge dynamics if enough data was available,and became a simple and powerful technique for analyzing the boundary.The results will provide further knowledge for understanding the interaction between forestry and agriculture in the arid valley.
    Landscape pattern variation of forest resources in typical forest zone of Changbai Mountains
    YU Deyong, HAO Zhanqing, JIANG Ping, XIONG Zaiping, YANG Hui
    2004, (10):  1809-1814. 
    Asbtract ( 1287 )   PDF (375KB) ( 258 )  
    Based on GIS and RS data of 1985 and 1999 and the ground infornmation from Lushuihe Forest Bureau, this paper studied the forest landscape pattern and its changes in typical forest zone of Changbai Mountains. According to the standard variance of patch areas in 1985 and 1999, the patch area distribution of mature conifer forest, mature broad-leaved forest, middle-aged conifer forest,and middle-aged broad-leaved forest、less symmetrical, showing that these land covers had landscape diversity and species diversity, According to landscape similarity index, the mature conifer forest, mature broad-leaved forest, middle-aged conifer forest and middle-aged broad-leaved forest,which were relatively stable than other land covers, made the majority of the landscape in the study area. According to patch density, the porosity of wetland was high in 1985 and 1999, indicating that wetland had little ho-mogenization and formed more mosaics. The fragmentation extent of farming land, due to multiple cultivating types, azimuths and shapes, was high in both phases. Attributing greatly to anthropogenic factors, the fragmentation extent of wetland was high all along. In brief, the forest landscape pattern was changed greatly in the studied phases, and human activities affected heavily on it.
    Impact of groundwater resource temporal-spatial change in Minqin oasis on ecological security of irrigation region landscape
    SONG Dongmei, XIAO Duning, MA Mingguo, WANG Jianhua
    2004, (10):  1815-1820. 
    Asbtract ( 1241 )   PDF (664KB) ( 305 )  
    By the GIS technology,this paper studied the impact of groundwater resource temporal-spatial change in the lake area of Minqin Oasis on the ecological security of irrigation region landscape.The results showed that the depth of groundwater was descending continuously,the velocity of groundwater line change in the center of irrigation region was faster than that in the edge region,and consequently,the area of the descending funnel of groundwater line was enlarged.From 1987 to 2001,the area with a groundwater depth deeper than 3 m was increased from 81.2% to 97.4%.The descending of groundwater line due to soil water reducing was the main reason that resulted in the destruction and deadness of forests.When the depth of groundwater was deeper than 8m and soil water content was less than 12%,the die-back rate of tree was morn than 90%,and that of shrub was more than 50%.Impacted by the descend of groundwater depth,the area of forest land,shrub land and open-canopy land was decreased by 67%,54% and 31%,and the number of their patches was decreased by 35,42 and 50,respectively.The mineralization degree of groundwater in northern irrigation region increased obviously,and changed the safe pattern of crop growth.The benefit of agriculture decreased,and the adjustment of planting construction was restricted seriously,which became the main impact factor on the ecological security of irrigation region.Reasonably distributing water resource between upper and lower river basin,reducing unreasonable land use,decreasing farmland area,and constructing safety landscape pattern could lead to the balance between the exploitation and replenishment of groundwater resource,prevent the descend of groundwater depth and the increase of groundwater mineralization,and improve the ecological security of the irrigation region.
    Application of spatially explicit landscape model in soil loss study in Huzhong area
    XU Chonggang, HU Yuanman, CHANG Yu, LI Xiuzhen, BU Renchang, HE Hongshi, LENG Wenfang
    2004, (10):  1821-1827. 
    Asbtract ( 1170 )   PDF (408KB) ( 249 )  
    Universal Soil Loss Equation(USLE)has been widely used to estimate the average annual soil loss.In most of the previous work on soil loss evaluation on forestland,cover management factor was calculated from the static forest landscape.The advent of spatially explicit forest landscape model in the last decade,which explicitly simulates the forest succession dynamics under natural and anthropogenic disturbances(fire,wind,harvest and so on)on heterogeneous landscape,makes it possible to take into consideration the change of forest cover,and to dynamically simulate the soil loss in different year(e.g.10 years and 20 years after current year).In this study,we linked a spatially explicit landscape model(LANDIS)with USLE to simulate the soil loss dynamics under two scenarios:fire and no harvest,fire and harvest.We also simulated the soil loss with no fire and no harvest as a control.The results showed that soil loss varied periodically with simulation year,and the amplitude of change was the lowest under the control scenario and the highest under the fire and no harvest scenario.The effect of harvest on soil loss could not be easily identified on the map;however,the cumulative effect of harvest on soil loss was larger than that of fire.Decreasing the harvest area and the percent of bare soil increased by harvest could significantly reduce soil loss,but had no significant effects on the dynamic of soil loss.Although harvest increased the annual soil loss,it tended to decrease the variability of soil loss between different simulation years.
    Dynamics of heat balance during growing season of broadleaved Korean pine forest in Changbai Mountains
    GUAN Dexin, WU Jiabing, WANG Anzhi, ZHAO Xiaosong, JIN Mingshu, XU Hao, DAI Guanhua, HE Xiu
    2004, (10):  1828-1832. 
    Asbtract ( 1298 )   PDF (498KB) ( 402 )  
    Based on the gradient measurement of microclimate factors,radiation and soil heat flux from late May to early October,2001 and by the method of Bowen ratio-energy balance (BREB),this paper estimated the latent heat and sensible heat above the broadleaved Korean pine forest in Changbai Mountains.The energy storage of forest air and vegetative was calculated,and the seasonal variations of heat balance components of the forest were analyzed.The results showed that the net radiation of the forest and the solar radiation were linearly correlated.All the heat balance components had the similar characteristics of diurnal variation to the net radiation,showing curves positive at daytime and negative at night,and the terms ranged as net radiation>latent heat>sensible heat>storage.The time of keeping positive terms in a day became shorter from June to October as influenced by shinning time.The highest net radiation was in June and the lowest in October.The monthly averaged net radiation was 0～527 and 0～-121 W·m-2,and the latent heat was 0～441 and 0～-81 W·m-2 for day and night,respectively.Sensible heat was 0～80 and 0～-26 W·m-2,and energy storage was 0～44 and 0～-26 W·m-2 for day and night,respectively.The ratio of latent heat to net radiation at daytime decreased gradually from August to October,and the ratio of sensible heat and energy storage increased correspondingly.Especially 2～3 days after the first sever frost,a sudden drop of latent heat and a sudden bounce of sensible heat were appeared.The instruments and measurement methods of heat flux were also concisely discussed in this paper.
    Impact of time series correction on forest CO2 flux
    WU Jiabing, GUAN Dexin, ZHAO Xiaosong, HAN Shijie, JIN Changjie
    2004, (10):  1833-1836. 
    Asbtract ( 1176 )   PDF (642KB) ( 365 )  
    Detrending correction and sonic anemometer tilt correction were made to modify the raw time series measured from eddy covariance system in broad-leaved Korean pine forest of Changbai Mountains during the growing season of 2003,and the impact of different correction methods on CO2 flux was analyzed quantificationally.The results showed that the forest CO2 flux during growing season was overestimated when calculated from raw time series.The ratio of correction to origin flux (Fcraw) was 1.6% and 1.8% for linear and nonlinear detrend,respectively,which suggested that there was little difference between these two detrending methods.It was 3.7% and 4.7% for the planar fit coordinate transforming (PF) correction and the streamline coordinate system transforming (ST) correction,respectively,suggesting that there was a clear difference between these two sonic anemometer tilt correction methods.When detrended time series used,it was 5.5 % and 4.6% for ST correction and PF correction,respectively.It was recommended that raw time series should be corrected synthetically with linear detrend method and PF method.
    Changes of carbon storage and carbon sequestration in plantation ecosystems on purple soil
    YU Zhanyuan, YANG Yusheng, CHEN Guangshui
    2004, (10):  1837-1841. 
    Asbtract ( 1163 )   PDF (809KB) ( 369 )  
    This paper studied the carbon storages and carbon sequestration capacities of degraded plantation ecosystems in purple soil area.Using space-time replacement method,four ecological restoration treatments (Ⅰ,Ⅱ,Ⅲ and Ⅳ) were selected on the basis of erosion intensions from high to low in Ninghua,Fujian.Treatment Ⅰ was not treated with any other measures after afforestation.Treatment Ⅱ adopted engineering soil and water conservation measure after afforestation.In treatment Ⅲ,the engineering measure associated biological measure was taken after afforestation.As for treatment Ⅳ,enclosure was adopted to protect against anthropogenic disturbances after afforestation.We observed that the carbon sequestration potential was increased with weakening erosion degree,i.e.,Ⅰ<Ⅱ<Ⅲ<Ⅳ.The carbon storage of 4 treatments was 1.4,8.5,25.6 and 37.6 t·hm-2,and the annual assimilation of CO2 was 712.87,1458.01,9718.10 and 11109.56 kg·hm-2,respectively.It was suggested that the restored forest ecosystem was one of the important carbon sinks in this area.Engineering soil and water conservation measure associated biological measure would be the main means of restoring degraded ecosystem.But presently,the reasonable strategy was to decrease human's disturbances,and hence,the enclosure for reforestation could be used to transform forest ecosystem into carbon sink.
    Soil biochemical characters of Pinus koraiensis and Pinus sylvestriformis plantations under different elevated CO2 concentration
    JIA Xia, HAN Shijie, ZHOU Yumei
    2004, (10):  1842-1846. 
    Asbtract ( 1278 )   PDF (818KB) ( 359 )  
    The aim of this study was to determine the dynamics of soil microbial biomass C,cellulose decomposition rate and catalase activity in Pinus koraiensis and Pinus sylvestriformis plantations exposed to elevated CO2 (700 mg稬-1 and 500 mg稬-1) during the growth season.The five years results indicated that in Autumn,the soil microbial biomass C of Pinus koraiensis and Pinus sylvestriformis plantations was in the order of ambient CO2-chamber>500 mg稬-1 CO2-chamber >700 mg稬-1 CO2-chamber.The monthly dynamics of cellulose decomposition rate in 5 and 10 cm depth soils showed that for both Pinus sylvestriformis and Pinus koraiensis plantations,it was always higher under 500 mg稬-1 CO2 than under 700 mg稬-1 CO2 in growth season.Between different CO2 concentration treatments,soil catalase activity of Pinus koraiensis and Pinus sylvestriformis plantations displayed a definite pattern of its monthly dynamics.
    Effects of free-air CO2 enrichment (FACE) on soil microbial biomass under rice-wheat rotation
    LI Yang, XU Guoqiang, HUANG Guohong, SHI Yi
    2004, (10):  1847-1850. 
    Asbtract ( 1261 )   PDF (492KB) ( 405 )  
    The effect of CO2 enrichment on soil microbial biomass in 0～5 cm and 5～10 cm soil layers under rice -wheat rotation was studied under the conditions of routine cultivation,irrigation and fertilization.The results showed that FACE treatment could significantly increase the amount of soil bacteria in 0～5 cm and 5～10 cm soil layers during rice jointing stage and wheat wintering and ripening stages.Elevated CO2 only significantly increased the amount of soil fungi in 0～5 cm soil layer during rice ripening stage.During the whole period of rotation,the amount of soil bacteria was greater than that of soil fungi.
    Effects of illumination,carbon source and reducing power on N2O emission from maize and soybean seedlings
    LI Yueying, YANG Yu, ZHANG Xudong, CHEN Guanxiong
    2004, (10):  1851-1854. 
    Asbtract ( 1296 )   PDF (485KB) ( 362 )  
    The closed chamber measurement of N2O emission from soybean and maize seedlings showed that there were two peaks (10:30 and 14:30) of N2O flux at the daytime.There was a correlation between N2O emission and illumination.The variation of illumination had a significant influence on N2O flux from soybean and maize seedlings.There was a positive correlation between N2O emission and illumination when the illumination was below 11 345 Lx (for soybean,R2 = 0.7332) or 2 000 Lx (for maize,R2 =0.8711),and a negative correlation when the illumination was over 11 345 Lx (for soybean,R2 = 0.7755) or 20 000 Lx (for maize,R2 =0.8972).Addition of carbon source (glucose) and NADH (reducing power) decreased N2O flux.
    Soil N2O and CH4 fluxes in broad-leaved Korean pine forest of Changbai Mountains
    XIAO Dongmei, WANG Miao, JI Lanzhu, HAN Shijie, WANG Yuesi
    2004, (10):  1855-1859. 
    Asbtract ( 1344 )   PDF (567KB) ( 431 )  
    The soil N2O and CH4 fluxes in the broad-leaved Korean pine forest of Changbai Mountains under two treatments were measured by static chamber-gas chromatograph.The results showed that litter significantly influenced N2O emission and CH4 uptake,and the effect efficiency was 36.9% and 23.4%,respectively.The N2O emission fluxes of the two treatments showed similar seasonal variations,with the highest in spring,higher in summer,and lower in autumn and winter.Furthermore,their diurnal variations were the same,the maxima both occurred at 18 o'clock,and the minima appeared at 12 o'clock and 14 o'clock.As for CH4 uptake fluxes,their seasonal variations were similar.The CH4 uptake fluxes were significantly higher in summer and autumn than in spring and autumn,and their diurnal variations were also the same,both went up from 14 o'clock to 18 o'clock and then started to go down until 6 o'clock.The results also indicated that soil N2O emission fluxes were negatively linear-correlated to CH4 uptake fluxes in the broad-leaved Korean pine forest.
    Soil seed bank in Keerqin meadow grassland under grazing and harvesting
    JIANG Deming, LI Rongping, LIU Zhimin, YAN Qiaoling
    2004, (10):  1860-1864. 
    Asbtract ( 1180 )   PDF (957KB) ( 372 )  
    This study on the size and composition of seed bank and its relationship with vegetation showed in Keerqin meadow grassland,the density of soil seed bank was 6 158?1 647 grains穖-2 under grazing and 8 312?2 540 grains穖-2 under harvesting.Under grazing,the seed bank was mainly composed of some dwarf and short-life annuals.The seeds of the annuals and biennials accounted for 81.66% of the seeds in seed bank.The four species with largest proportion of seed bank were Chloris virgata,Chenopodium glaucum,Digitaria cilliaris and Setaria viridis,and the proportions were 38.55%,15.42%,14.95%,and 9.83%,respectively.The density of perennials in soil seed bank was 1 129?302 grains穖-2.Under harvesting,the seeds of annuals and biennials accounted for 68.08% of the seed in seed bank,and the proportion of Setaria viridis was 52.7%.In the harvesting meadow grassland,the seed density of perennials was 2 653?811 grains穖-2.There was no significant correlation between the seed density in soil and the vegetation under grazing,but a significant correlation between the seed density in soil and the species abundance of vegetation under harvesting (r=0.76,P<0.01).The index of Shannon-Wiener and richness of grazing meadow grassland were 2.96 and 2.98,respectively,distinctly smaller than 3.10 and 5.09 of harvesting meadow,which showed that free grazing made the diversity of seed bank decrease easily.
    Effects of sand-burying on seed germination and seedling emergence of six psammophytes species
    LI Rongping, JIANG Deming, LIU Zhimin, LI Xuehua, LI Xiaolan, YAN Qiaoling
    2004, (10):  1865-1868. 
    Asbtract ( 1391 )   PDF (549KB) ( 427 )  
    This paper studied the effects of sand-burying on the seed germination and seedling emergence of six dominance plants in Keerqin Sandy Land.Six treatments of artificially sand-burying to depths 0,2,4,6,8,10 and 12 cm were designed.The results showed that the seed germination of Agriophyllum squarrosum was significantly different(P<0.05)between different treatments,but that of Artemesia halodendron was only significantly different(P<0.05)between 2 cm and other burial depths.For other four plants,their seed germination was significantly different(P<0.05)only between 0 cm and other burial depths.Sand-burying significantly affected the seedling emergence of all plant species.The emergence rate decreased with increasing burial depth.Higher emergence percentages were obtained at 2 and 4 cm burial depths.The species with larger seeds emerged from deeper depth,and the maximum burial depth of seedling emergence was Sophora flavescdens>Atraphaxis manshurica≥Agriophyllum squarrosum>Hedysarum fruticosum>Bassia dasyphylla>Artemesia halodendron.
    A comparative study on mucilaginous diaspores of four plant species
    LIU Zhimin, YAN Qiaoling, LUO Yongming, WANG Hongmei, LI Rongping, LI Xuehua
    2004, (10):  1869-1872. 
    Asbtract ( 1219 )   PDF (470KB) ( 352 )  
    A comparative study was conducted on the mucilaginous diaspores of Thymus serpyllum,Plantago depressa,Plantago maritima,and Linum stelleroides.The mucilage amount was estimated by the sand-holding capacity of seed under soaking and watering conditions.Soaking and watering experiments each had 4 treatments.The results indicated that under different soaking time treatments,the mucilage amount of Linum stelleroides and Plantago depressa was of nonsignificant difference,but that of Plantago maritima and Thymus serpyllum was increased with prolonged soaking-time.Under different watering treatments,the mucilage amount of the 4 plant species all had an increasing trend along with the increased water volume.After soaking for 80 min,the weight of sand-holding seed of Plantago maritima was 60 times more than its seed weight,Plantago depressa was 10 times,and Thymus serpyllum and Linum stelleroides was 4～6 times.After watering with 8 mm rainfall,the weight of sand-holding seed of Plantago maritima was 20 times more than its seed weight,Plantago depressa was 6～10 times,and Thymus serpyllum and Linum stelleroides was 2～7 times.In averaging various treatments,the percentage of the sand-holding seed to the total seed of Linum stelleroides,Thymus serpyllum,Plantago depressa and Plantago maritima was 67.7%,94.5%,97.7% and 99.5%,respectively.
    Introduction of upland rice cultivars to eastern Keerqin sandy land and their biological characteristics
    ZENG Dehui, ZHANG Chunxing, WANG Guirong, FAN Zhiping
    2004, (10):  1873-1877. 
    Asbtract ( 1221 )   PDF (261KB) ( 256 )  
    Developing water-saving rice cultivation is one important strategy for food security in China.This paper reported the experimental results of introducing six upland rice cultivars to eastern Keerqin sandy land.The filed experiment results showed that under the condition of 60% water-saving,the yield of cultivars XH 95-13 and XH 95-13-6 was 10.2% and 5.5% higher than the control,respectively,while other four cultivars decreased by 6.7%～18.6%.Economically,all the cultivars except JP 121 had a higher income than the control,and the profitability of cultivars XH 95-13 and XH 95-13-6 reached 24.0% and 19.3%,respectively.The water productivity of all the six cultivars was over 0.566 kg·m-3,increased by 59.89%～116.38%.Pot experiment showed that 12.1%～16.3% of soil moisture in 0～15 cm layer was beneficial to the growth of upland rice.In eastern Keerqin sandy land,effective tillers occurred before July 18.In brief,upland rice production could be extensively applicable in eastern Keerqin sandy land to gradually alternate the traditional lowland rice cultivation with continuous flooding,and save much underground water.
    Photosynthetic characters and Bt toxin content of different transgenic Bt cottons
    SUN Caixia, CHEN Lijun, WU Zhijie, WU Qiong, CHEN Cuiwei
    2004, (10):  1878-1882. 
    Asbtract ( 1230 )   PDF (667KB) ( 341 )  
    The study on the photosynthetic characters and Bt toxin content of different Bt cottons(ZK,GK)and non-Bt cotton(CZ)indicated that Bt cottons GK and ZK had different total expressed amount of Bt toxin and its distribution in different tissues.The Bt cottons had obviously different chlorophyll contents,responses of photosynthetic rate to photosynthetic active radiation,and diurnal changes of photosynthetic rate and transpiration rate,but the diurnal change of leaf temperature,CO2 concentration inside leaf cells and stomatal limit values were approximately the same.There was a significant difference between two transgenic Bt cottons in the diurnal average value of CO2 concentration inside leaf cells,but the differences in other characteristics were not significant among different cottons.
    Influence of acetochlor on Pb forms and their bioavailability in phaiozem of northeast China
    ZHOU Qixing, SUN Fuhong, GUO Guanlin, SUN Tieheng
    2004, (10):  1883-1886. 
    Asbtract ( 1214 )   PDF (228KB) ( 406 )  
    By using Pb-fractionation analytical methods and Pb-acetochlor response experiments,it was studied the Pb forms in clean and polluted phaiozems of northeast China and the response of Pb bioavailability to acetochlor application.The results showed that the dominant Pb forms in these soils were low bio-available organic-sulfide Pb and residual Pb,and the concentrations of high bio-available water-soluble and exchangeable Pb were relatively low.However,the ratio of bio-available Pb to total Pb was lower in polluted phaiozem than in clean phaiozem.The bioavailability of Pb in the soil was obviously increased after high dose of acetochlor was applied.The main reason was the contribution of organic-sulfide Pb to bio-available Pb interacted with acetochlor.
    Accumulation of soil inorganic nitrogen in mono-harvesting farmlands of northeast China in late autumn
    CHEN Xin, ZHANG Qingzhong, LU Caiyan, SHI Yi, ZHANG Lu
    2004, (10):  1887-1890. 
    Asbtract ( 1158 )   PDF (224KB) ( 330 )  
    The study showed that in northeast China,the farmlands with a mono-harvesting agricultural system had a low accumulation of soil inorganic nitrogen after harvest.In late autumn,there was an interval of about 20～30 days when the temperature and humidity were appropriate to soil N mineralization,but the mineralized nitrogen could not be used by crops in this non-growing season.The accumulation of inorganic nitrogen in upland soil reached a high level before freezing.Its inorganic nitrogen content in 1m depth soil was 99.9 kg·hm-2 in the treatment of commercial fertilizers(N 150 kg·hm-2;P 16.4 kg·hm-2;K 62.3 kg·hm-2)and 145.4 kg·hm-2 in the treatment of commercial fertilizers plus manure(pig manure by a reutilization of 80% product).While in rice field,its inorganic nitrogen content was relatively low before freezing.The reason might be that the soil permeability was not as good as that in upland for its long-term water-logging,and its insufficient aeration would be favorable to denitrification which induces the inorganic nitrogen loss via N2O emission.
    Dynamics of microbial biomass N in different fertilized black soil and its related factors
    LI Dongpo, CHEN Lijun, WU Zhijie, ZHU Ping, REN Jun, LIANG Chenghua, PENG Chang, GAO Hongjun
    2004, (10):  1891-1896. 
    Asbtract ( 1213 )   PDF (864KB) ( 412 )  
    This paper studied the dynamics of microbial biomass N in a black soil long-term fertilized with farmyard manure(M2 and M4)and chemical fertilizer(NPK)during crop growth season.The results showed that the soil microbial biomass N was 25.52～239.12 mg·kg-1 in M4,10.40～94.31 mg·kg-1 in M2,6.27～87.04 mg·kg-1 in NPK,and 9.15～69.81 mg·kg-1 in CK.In same treatment,the highest value was 7～14 times higher than the lowest value.Treatments NPK and M2 had the highest value of microbial biomass N at reproductive growth stage,while M4 and CK had it at vegetative growth stage.The significant difference of soil microbial biomass N caused by different treatments was not changed with plant growth stages.The dynamics of soil microbial biomass N had a significant correlation some soil biological,physical and chemical properties.A significant positive correlation was found between soil microbial biomass N and soil biological,physical and chemical properties,plant N,P and K contents,soil moisture,and grain crude protein.
    Dynamics of microbial biomass P and its affecting factors in a long-term fertilized black soil
    LI Dongpo, WU Zhijie, CHEN Lijun, ZHU Ping, REN Jun, LIANG Chenghua, PENG Chang, GAO Hongjun
    2004, (10):  1897-1902. 
    Asbtract ( 1094 )   PDF (734KB) ( 420 )  
    This paper studied the microbial biomass P in a long-term fertilized black soil.The soil was fertilized by farmyard manure(M2,M4)and chemical fertilizer(NPK),and the dynamics of soil microbial biomass P was monitored during crop growth season.The results showed that the microbial biomass P in different treatments was 8.75～47.68 mg·kg-1(M4),3.02～37.16 mg·kg-1(M2),1.59～10.62 mg·kg-1(NPK),and 0.76～6.74 mg·kg-1(CK).The microbial biomass P in M4 and M2 was the highest at reproductive growth stage,and that in NPK and CK was the highest at early growth stage.The significant difference of soil microbial biomass P induced by different amounts and types of fertilizer application was not varied with the period and stage of plant growth.In all treatments,no significant correlation was found between the dynamics of soil microbial biomass P and the soil biological,physical and chemical properties in plant growth period.Soil microbial biomass P had a very significant positive correlation with soil biological,physical and chemical properties(expect K),and a significant positive correlation with the N,P and K contents of plants and soil water content.
    Effects of urease/nitrification inhibitors on soil available N and microbial biomass N and on N uptake of wheat
    JIAO Xiaoguang, LIANG Wenju, CHEN Lijun, JIANG Yong, WEN Dazhong
    2004, (10):  1903-1906. 
    Asbtract ( 1264 )   PDF (527KB) ( 540 )  
    With an aquic brown earth as test soil,this paper studied the effects of urease inhibitor(NBPT),nitrification inhibitor(DCD)and their combinations on the dynamics of soil available N and microbial biomass N.The results showed that the treatments of inhibitors,especially the combined application of NBPT and DCD,could increase soil NH4+-N by 2%～53%,inhibit NH4+ oxidation,decrease soil NO3--N concentration,increase soil total available N by 34%～44%,and increase wheat N uptake by 0.26%～6.79%.The best treatment was urease inhibitor combined with nitrification inhibitor.The application of inhibitors increased soil microbial biomass N immobilization at the early growth stage of wheat,and promoted soil N mineralization at filling stage.
    Effects of long-term fertilization on soil microorganism and its role in adjusting and controlling soil fertility
    SUN Ruilian, ZHU Lusheng, ZHAO Bingqiang, ZHOU Qixing, XU Jing, ZHANG Fudao
    2004, (10):  1907-1910. 
    Asbtract ( 1328 )   PDF (583KB) ( 827 )  
    To clarify the relationships between soil microorganisms and soil fertility under the condition of long-term fertilization,a 12-year fertilization experiment was installed on a fluvo-aquic soil,and the amount of soil microorganisms and the content of soil nutrients were determined and analyzed.The results showed that chemical fertilizers combined with organic manure could significantly improve soil fertility and increase the amount of soil microorganisms.Organic manure was obviously superior to corn straw in improving soil fertility.The correlation between soil microorganisms and soil fertility was significant.A positive correlation was found between the amount of bacteria and azotobacteria and the contents of organic matter,total N,alkalified N,total P and available P.The relationship between the amount of fungi and actinomycetes and the content of soil nutrients was not obvious.
    Effects of intermittent irrigation on ecological and physiological water requirement of rice in north China
    WANG Xiaoying, LIANG Wenju, WEN Dazhong
    2004, (10):  1911-1915. 
    Asbtract ( 1298 )   PDF (255KB) ( 268 )  
    The ecological and physiological water requirement of rice was studied in a paddy field of north China,and the field experiment was conducted at Shenyang Experimental Station of Ecology,Chinese Academy of Sciences.Under continuous flooding irrigation(CSF) and intermittent irrigation(IT) conditions,the evapotranspiration and soil evaporation of paddy fields were measured by non-weighing lysimeters and micro-lysimeters,respectively.The results showed that compared with continuous flooding irrigation,the transpiration under intermittent irrigation condition was not significantly reduced,but 16% and 24% of water amounts were reduced by decreasing the water losses through soil water evaporation and percolation,respectively.The water use efficiency of intermittent irrigation was increased 10%,without any adverse effects on biomass and grain yield of rice.Although the amount of water requirement under IT treatment was reduced significantly compared with CSF treatment,about 60% of total water requirement was still lost through deep percolation.Based on the results obtained,the corresponding countermeasures to reduce the amounts of soil water evaporation and percolation and to increase the water use efficiency were put forward in this paper.
    Comprehensive evaluation of cultivated black soil fertility
    MA Qiang, YU Wantai, ZHAO Shaohua, ZHANG Lu, SHEN Shanmin, WANG Yongbao
    2004, (10):  1916-1920. 
    Asbtract ( 1284 )   PDF (274KB) ( 412 )  
    Black soil is one of the main soil types in northeastern China,and is a valuable soil resource of this country.Based on the analysis of the physical and chemical properties of soil samples collected from the north-south transaction of black soil,the index system of black soil fertility was established,the fertility level was evaluated and classified by Fuzzy and Factor Analysis,and the fertility map of black soil zone was drawn with GIS software ArcInfo.It was found that the humus layer in black soil region was thick in north and thin in south,which was due to the climatic condition and soil-forming process.The soil fertility level was high in east and low in west.From north to south,it was decreased in the order of central part >northern part >south part.In most part of this region,soil fertility level was medium,and the area accounted for 73.6% of the black soil area.
    Effects of water managements on soil nematode communities in a paddy field
    OU Wei, LI Qi, LIANG Wenju, JIANG Yong, WEN Dazhong
    2004, (10):  1921-1925. 
    Asbtract ( 1370 )   PDF (276KB) ( 249 )  
    This paper studied the effect of water managements on the abundance,trophic groups and community composition of soil nematodes in a paddy field in the Lower Reaches of Liaohe Plain at the depths of 0～10 cm,10～20 cm and 20～30 cm during rice(Oryza sativa L.)growth season.The total number of nematodes at 0～10 cm soil depth was lower in percolation-controlling treatments than in control during pre-tillage and yellow ripeness stage.No significant difference was found in the total number of nematodes at 10～20 cm soil depth during the study period,but significant difference was observed in 20～30 cm soil depth during pre-tillage and yellow ripeness stage.Sixteen families and 22 genera were observed,and Plectus,Tylenchus and Monhystera were the dominant genera.Plectus and Tylenchus were sensitive to different water managements.Significant difference was found in the number of bacterivores at 0～10 cm soil depth during pre-tillage and yellow ripeness stage in percolation-controlling treatments,which exhibited a similar trend with the total number of nematodes.Bacterivores and plant-parasites were the most abundant trophic groups in all plots and at all soil depths during the study period,averaging 60.8% and 33.8% of the nematode communities,respectively,and omnivores-predators were the least abundant groups.
    Accumulation of pollutants in sediments and their eco-toxicity in the wastewater irrigation channel of western Shenyang
    SONG Yufang, ZHOU Qixing, SONG Xueying, ZHANG Wei, SUN Tieheng
    2004, (10):  1926-1930. 
    Asbtract ( 1246 )   PDF (572KB) ( 327 )  
    Sediment samples were collected from several sites in the upper,mid and lower reaches of the petroleum wastewater irrigation channel in western Shenyang of China,and the concentrations of their heavy metal Cd and mineral oil were determined.The results showed that pollutants were accumulated in all test sediments,with 400～12 500 mg·kg-1 mineral oil and 1.6～27.2 mg·kg-1 Cd.The sediments had significant inhibition effects on plant and earthworm.The inhibition rate of root elongation based on germination test was 10%～60%.During 14 d and 28 d exposure,the mortality rate of earworm was 0%～70% and 0%～85%,and the inhibition rate of its body weight growth was -21.9%～17.7% and -18.6%～37.0%,respectively.It indicated that a long-term irrigation with wastewater resulted in the accumulation of pollutants in channel sediments and enhanced eco-toxicity.As an important source of pollution,the migration and release of pollutants in sediments possessed potential risks to underground water and soil.
    Seasonal dynamics of Batrachospermum gelatinosum growth and distribution in Niangziguan spring,China
    XIE Shulian
    2004, (10):  1931-1934. 
    Asbtract ( 1257 )   PDF (221KB) ( 218 )  
    This paper studied the seasonal dynamics of the growth and distribution of freshwater rhodophyte Batrachospermum gelatinosum in Niangziguan of Pingding County,Shanxi Province,North China,from September 1992 to June 1994.The water temperature,pH,current velocity,occurrence frequency,mean cover,plant height,whorl diameter,fascicle length,carpogonial branch length,carpogonium length,carpogonial diameter,carposporophyte number per whorl,carposporophyte diameter,carposporangium length and carposporangium diameter were examined regularly.The results showed that water temperature was the maximum in July and minimum in January,water pH had little change,and the variation of current velocity was irregular.The occurrence frequency and mean cover of the alga were increased from Autumn to Spring,and the highest were in May.The seasonal growth dynamics of this alga were evident.It developed well from late Autumn to early Summer,and peaked in May.It was positively correlated to each other among morphological characteristics,and the development was synchronal in all parts of the plant.
    Ecological function of wood-inhabiting fungi in forest ecosystem
    WEI Yulian, DAI Yucheng
    2004, (10):  1935-1938. 
    Asbtract ( 1339 )   PDF (501KB) ( 423 )  
    Wood-inhabiting fungi are one of the most important parts of forest ecosystem,and play an important role in degrading the wood in forest ecosystem.The major species of these fungi include the groups of Aphyllophorales (Basidiomycota),Discomycetes (Ascomycota) and some imperfect fungi.They have the ability to degrade cellulose,hemicelluloses and lignin of wood.Three type of wood decaying have been found,i.e.,white rot,brown rot and soft rot.Many other organisms of forest ecosystem have symbiosis relationship with wood-decaying fungi.Wood-inhabiting fungi could offer the nutrition for many insects and birds,and spores of many wood-rotting species are spread by some insects.The high biodiversity of wood-decaying fungi is one of the important factors for the health of forest ecosystem.
    Research advances in bryophyte ecological function
    YE Ji, HAO Zhanqing, YU Deyong, YAN Haibing, FENG Dequan
    2004, (10):  1939-1942. 
    Asbtract ( 1249 )   PDF (523KB) ( 470 )  
    Though the body of bryophyte is small,its species is abundant (about 23000),being an important part of biodiversity.The previous studies were focused on its taxology,while its ecological functions in ecosystem were ignored.Bryophyte can adapt to various environments,distribute in many extreme surroundings,and has rebuilding ability to environments.It has a very strong ability of holding and absorbing water,especially the epiphytic bryophyte can intercept a great deal of rain,and its function in water circulation is very obvious.Bryophyte can absorb a lot of nutrient elements by body surface,but its function in nutrient cycling was usually ignored.In some extreme environments,bryophyte is the important primary producer.Sphagnum biomass is more enormous,and maybe,is the important C pool.Bryophyte can sensitively response to the air and heavy metal pollution,and is a kind of bio-indicators.In order to promote the further studies on bryophyte ecological function,the related research advances were reviewed in this paper.
    Function and application of soil microorganisms in forest ecosystem
    LI Yanmao, HU Jiangchun, WANG Silong, WANG Shujin
    2004, (10):  1943-1946. 
    Asbtract ( 1503 )   PDF (491KB) ( 726 )  
    Soil microorganism is an important part of forest ecosystem,and plays an important role in sustainable development of forestry.In this paper,we summarized the main functions of soil microorganisms in forest sustainable development from the aspects of 1)the role of soil microorganism and microbiomass;2)the function of mycorrhizal fungi;3)the impact of pathogen;and 4)the effect of PGPR.Finally,we also discussed the research trends of forest soil microorganism and its application.Some study areas which should be further studied were also proposed.
    An overview on studies of soil organic matter in Chinese fir plantation
    WANG Qingkui, WANG Silong, FENG Zongwei, DENG Shijian, GAO Hong
    2004, (10):  1947-1952. 
    Asbtract ( 1155 )   PDF (247KB) ( 323 )  
    Soil organic matter(SOM) is an important component of soil and an important carbon pool of terrestrial ecosystems,which plays an important role in soil nutrient cycling and in the balance of global carbon cycle.This paper discussed the SOM quality in Chinese fir plantation,the influence of rotation on SOM content,the change of SOM during Chinese fir growth,and the effect of human activities such as burning,site preparations and fertilization on SOM.Human activities changed soil environment including soil moisture,temperature,total porosity and nutrient contents,and hence,made the turnover of SOM slower or quicker.The content and quality of SOM in mixed forests were higher than those in pure Chinese fir plantations,and decreased with rotation.In the last part of this paper,some issues to be further researched were put forward,including the turnover model of SOM,its components,and its relationship with global carbon cycle.
    Degradation mechanism of Chinese fir plantation
    CHEN Longchi, WANG Silong, CHEN Chuying
    2004, (10):  1953-1957. 
    Asbtract ( 1179 )   PDF (579KB) ( 331 )  
    Chinese fir (Cunninghamia lanceolata) is a fast-growing species native to China,and has a very important status in production of commercial timber.In response to the growing need for timber,pure Chinese fir plantations have been extensively replanted on the same site in successive rotations,which has resulted in serious problems of soil fertility degradation and productivity decline,and these problems have caused considerable attention from foresters,microbiologists,soil scientists and ecologists.They have also done a lot of work on these problems and studied the mechanism of productivity decline of replanted Chinese fir plantation.In this article,the author described the characteristics of productivity decline and soil degradation,and summed up the factors caused lower productivity,and analyzed the degradation mechanism of replanted Chinese fir plantation.In sum,productivity decline and soil physical and chemical characteristics deterioration were the main properties of replanted Chinese fir plantation.The factors summarized primarily as two kinds of reasons.One was the unreasonable management that was the edogenic factor,and another was the biotic self-characteristics of Chinese fir that was the intrinsic factor of poor establishment of replanted Chinese fir plantation.The combination of the edogenic and intrinsic factors reduced the productivity decline and soil degradation of the replanted Chinese fir plantation.
    Research advances in soil fungal diversity and molecular ecology
    ZHANG Jing, ZHANG Huiwen, LI Xinyu, ZHANG Chenggang
    2004, (10):  1958-1962. 
    Asbtract ( 2095 )   PDF (568KB) ( 782 )  
    Fungi are a kind of important soil microorganisms that participate in the decomposition of organic materials and supply nutrients to the plant through symbiosis.But,they can also reduce the output of food due to the existence of pathogenic fungi.Soil fungal diversity plays a fundamentally unique role in maintaining the balance of ecosystem and in supplying large amount of undeveloped resources for the people.In this paper,soil fungal diversity was expatiated from the viewpoints of species diversity,habitant diversity and functional diversity,and furthermore,the research advances in the molecular ecology of soil fungal diversity were reviewed from the aspects of the fungal diversity of farmland,woodland,pasture,extreme environment,and other complex environments.The affecting factors of soil fungal diversity were discussed,and the development trend of the study on soil fungal diversity was also approached.
    Research advances in plant growth-promoting rhizobacteria and its application prospects
    HU Jiangchun, XUE Delin, MA Chengxin, WANG Shujin
    2004, (10):  1963-1966. 
    Asbtract ( 1766 )   PDF (532KB) ( 1124 )  
    The study of plant growth-promoting rhizobacteria will provide possible methods to overcome the difficulties in controlling soil borne plant diseases.PGPR can colonize in rhizosphere at high population density,inhibit plant pathogens and deleterious microorganisms there,and promote crop growth and its yield.More importantly,some PGPR strains applied as biocontrol agents can make treated plant produce induced systemic resistance (ISR),and thus,increases plant overall health.In recent two decades,the researches of PGPR in abroad are very active,and many PGPR products have been applied successfully.In our contry,more attention should be paid to the study of the basic theory and application of GPPR and the industrialization of PGPR products.
    Research advances in wheat (Triticum aestivum) allelopathy
    ZHANG Xiaoke, JIANG Yong, LIANG Wenju, KONG Chuihua
    2004, (10):  1967-1972. 
    Asbtract ( 1341 )   PDF (695KB) ( 479 )  
    Wheat (Triticum aestivum) is the main food crop in the world,and plays an important role in agricultural production.In order to enhance wheat yield,herbicides and germicides were intensively applied and made negative effects on the environment.Wheat possesses allelopathic potential for weed suppression and disease control through the release of secondary metabolites from its living plants or residues,which could avoid the environment pollution brought by herbicides and germicides.This paper reviewed the research advances in wheat allelopathy.Hydroxamic acids and phenolic acids are the predominant allelochemicals frequently reported which could produce plant natural defense against weed,pest and disease.The allelopathic activity of allelochemicals is determined not only by the allelochemicals,but also by the factors of inheritance,environment and biology.The retention,transportation and transformation processes of allelochemicals,and the relationship between wheat allelopathy and soil biota and its mechanism were seldom studied and still needed to be researched profoundly.Utilizing wheat allelopathy in plant protection,environment protection and crop breeding would improve the stress-resistance,yield and quality of wheat in agricultural production.
    Soil nematode as a bioindicator of environment pollution
    ZHANG Wei, SONG Yufang, SUN Tieheng, SONG Xueying, ZHOU Qixing
    2004, (10):  1973-1978. 
    Asbtract ( 1244 )   PDF (931KB) ( 593 )  
    As a part of mesofauna in soil ecosystem,nematode plays an important role in essential soil processes.Because of its unique attributes,nematode was widely used in the study of soil health indication.Based on the current studies at home and abroad,this paper discussed the function and application of nematode in indicating and diagnosing soil pollution,and the indices (maturity index,diversity index,similarity index,key species,N/C ratio,and physiological index) and their characteristics of nematode communities used as indicators.As a useful index of bioindicators in ecotoxicological diagnosis,the prospect of soil nematode application was of potential.
    Bio-indicating function of soil protozoa to environmental pollution
    SONG Xueying, SONG Yufang, SUN Tieheng, ZHANG Wei, ZHOU Qixing
    2004, (10):  1979-1982. 
    Asbtract ( 1874 )   PDF (499KB) ( 521 )  
    Due to the abundant species and huge biomass,soil protozoa play an important role in soil ecosystem.As a bio-indicator,soil protozoa have many advantages over other soil animals.Studies on the community structures,quantities,and dynamic variations of biodiversity of soil protozoa could provide powerful means to evaluate natural environmental changes and to monitor the environmental pollution brought by anthropic activities.Based on the current study at home and abroad,this paper gave a review on the function of soil protozoa in ecosystems,their advantages as bio-indicator,and their responses to environmental factors,soil contaminants and the change of atmospheric CO2.The application prospect of soil protozoa in eco-toxicity diagnosis was also discussed.
    Research advances in DNA adducts:Their formation,diagnosis and pollution-exposure indication
    WANG Mei'e, ZHOU Qixing
    2004, (10):  1983-1987. 
    Asbtract ( 1394 )   PDF (873KB) ( 379 )  
    With the cognitive penetration of ecotoxicological effects into a molecular level,more attention has been paid to the research on DNA adducts.This paper analyzed toxic mechanisms and formative processes of DNA adducts,and introduced in brief their diagnostic methods,including chromatogram-mass spectrum method, 32P post-labeling method,immunology method and fluorescence method.The pollution-exposure indication of DNA adducts was expounded as an effective molecular biomarker,and thus,DNA adducts could be used by ecotoxicologists as a good caution signal in forecasting hazardous effects of pollutants.