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1.
里骆林区常绿阔叶林和人工杉木林气候水文效应   总被引:13,自引:2,他引:11  
里骆林区常绿阔叶林和人工杉木林气候水文效应黄承标,文受春(广西农学院林学分院南宁530001)(广西龙胜县林业局541700)ClimaticandHydrologicalEffectsofEvergreenBroad-leavedandArtificialChineseFirForestsinLiluoForestedRegion¥HuangChengbiao(ForestryCollege,CuangxiAgriculturalUniversity,Nanning530001),WenShouchun(ForestryBureau,LongshengCounty,Guangxi541700);ChineseJournalofEcol-ogy,1993,12(3):1-7.Siteinvestigationsandresearchesin1980-1990showthatevergreenbroad-leavedandartificialChinesefirfOrestsinLiluoforestedregioncanreducethevariationrangeofatmosphericandsoilt  相似文献   

2.
祁连山植被水文效应的多层次Fuzzy综合评判   总被引:8,自引:0,他引:8  
祁连山植被水文效应的多层次Fuzzy综合评判车克钧,傅辉恩(甘肃省张掖祁连山水源林研究所734000)Multiple-LevelFuzzyComprehensiveEvaluationonHydrologicalFunctionsofVegetationsontheQilianMountains¥.CheKejun;FuHuien(QilianMountainsInstituteofForestforWaterSourceConservation,Zhangye,GansuProvince734000).ChineseJournalofEcology,1993,12(3):31-35.BymeansofmuItiple-levelfuzzycomprehensiveevaluation,thehydrologicalfunctionsoffourvegetationtypesareanalyzed.PiceacrassifoliaforestisshowntobethebesttypeforwaterconservationonQilianmountains,Sabinaprzewlskiiforesta  相似文献   

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福建中亚热带村级农业生态经济类型的成因与发展机制研究林文雄,吴志强,林群慧,郑世庆,王松良,梁义元(福建农学院,福州350002)ContributingFactorandDevelopmentMecbanismofRuralAgro-ecolomicTypesinMid-subtropicalRegionofFuJianProvince¥.LinWenxiong;WuZhiqiang;LinQunhui;ZhengShiqing;WangSongliang;LiangYiyuan(FujianAgriculturalCollege,Fuzhou350002).ChineseJournalofEcology,1993,12(2):66-68.Usingsystematicanalysismethodtheauthorsstudiedthestatuecharacteristicsandtheirvariationpat-ternsofruralagro-ecolomictypeinmid-subtropicalregionofFujianprovince.11tapesofsystemstructurean  相似文献   

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生态位理论及其在森林生态学研究中的应用   总被引:47,自引:4,他引:43  
生态位理论及其在森林生态学研究中的应用朱春全(中国林业科学研究院林业研究所,北京100091)NichcTheoryanditsApplicationinForestEcology¥.ZhuChunquan(InslituteofForestry,ChineseAcademyofForestrySciences,Beijing100091),ChineseJournalofEcology,1993,12(4):41-46.Thedevelopmentofnichetheoryanditsapplicationinforestecologicalstudyarereviewedinthispaper.Itispointedoutthatthefunctionalactionofplantunitwasnotinvolvedinpreviousnicheconcepts,Theparticularitiesofnicheofplantunitarediscussedandanewmethodisdevelopedtodetermineitwithpho-tosyntheticproductionasafunct  相似文献   

5.
河西走廊农户生态系统农田能流和物流数量特征的研究   总被引:6,自引:0,他引:6  
河西走廊农户生态系统农田能流和物流数量特征的研究李发弟(甘肃农业大学畜牧系,兰州730070)QuantintiveCharacteristicsofEnergyFlowandNutrientCyclingofFarmlandinaFarmEcosysteminHexiCorridor¥LiFadi(DepartmentofAnimalHusbandry,GansuAgriculturalUnitversity).ChineseJour-nalofEcology,1993,12(6):37-40.Quantitativecharacteristicsofenergyflowandnutrientcyclingoffarmlandsubsysteminafarmecosys-teminHexiCorridorwerestudied.Theresultsshowedthatthedeflreeofopening,inputandoutputwerehigh,theratioofoutputtoinputofsubsidyenergy,nitrogenandphosphorusofthefarmlandsubsy  相似文献   

6.
落叶松人工林土壤肥力变化的研究   总被引:10,自引:1,他引:9  
落叶松人工林土壤肥力变化的研究阎德仁(内蒙古林业科学研究院呼和浩特市010010)SoilFertilityVariationsUnderArtificialLarchForest¥.YanDeren(ForesiryInstiluteofInnerMongolia,Huhhot010010).ChiineseJournalofEcology,1993,12(3):8-10.Thispaperstudiesthevariationofsoilfertilityunderpureartificiallarch(Larixgmelinii)forestfromas-pectsofsoilhumusandenzymeactivity.Withincreasingageofforeststand,soilfertilitytendstode-crease,butsoilenzymeactivitytendstoincrease.Underforestwith20yearsofage,thecontentsofsoilhumus,humicacidandfulvicacidandtheratioofhumicacid  相似文献   

7.
生物固氮─—生态农业的一个重要启动因素陈士平(辽宁省农业科学院土壤肥料研究所,沈阳110161)BiologicalNitrogenFixation—AnImportantRunningFactorofEcologicalAgriculture¥.ChenShiping(SoilandFertilizerInstilute,LiaoningAcademyofAgriculturalSciences,Shenyang110161).ChineseJournalofEcology,1993,12(2):31—33.LeguminousgreenmanurecropssuchassweetcloverandAstragalushuangheensis,canprovidedefiniteamountofbiologicallyfixed-NtomakeN-budgetbalance,promotesoilphysicalandchemicalproper-ties,reducesoilandwatererosion,andthus,increaseperunitareayieldandtotaloutputwhe  相似文献   

8.
南山暖性次生针叶林的Fuzzy数学分类余小平(重庆师范学院生物系,630047)FuzzyNumericalClassificationofWarmSecondaryConiferousForestatNansanMountain¥.YuXiaoping(DepartmentofBiology,ChongqingTeachers’College,630047);ChineseJournalofEcology,1993,12(4):23-26.NumericalclassificationsaremadeformassonpinecommunitiesinwarmsecondarvconiferousforestatNansanmountain.Fuzzyaggregationanalysisisapplied,andsixasxoclationgroupsandtenassociationsareclassified.Theresultsofclassificationcoincidewithactualconditionsofvegetationresources.Keywords:association  相似文献   

9.
TBP的联结因子TAFs的结构与功能潘建伟赵章杏朱睦元(杭州大学生命科学学院,杭州310012)潘伟槐黄承才(绍兴文理学院生化系,绍兴31200)StructuresandFunctionsofTBP-asociatedFactorsTAFsPANJ...  相似文献   

10.
洞庭湖滩血吸虫易感地带保水生态灭螺的试验研究张元培,朱南屏(湖南省水产科学研究所沅江413100)(湖南省华容县血防站414200)EcologicalEIiminationofSnail(Oncomelania)byRctainingWaterinBloodFluke(Schistosoma)Suscepti-bleRegionsAroundDongtingLake¥.ZhangYuanpei(InstituteofFisheriesResearchofHunanProvince,Yuanjiang413100),ZhuNanbing(StationofSnailFeverControlofHuarongCounty,HunanProvince,414200).ChineseJournalofEcology,1993,12(3):23-25.Inbloodfluke(Schistosoma)susceptibleregionsofthelakebeach,experimentsofwaterinundatedelimi-natingsnail(Oncomelania)arecarriedoutbybuil  相似文献   

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It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.  相似文献   

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Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.  相似文献   

17.
Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.  相似文献   

18.
肝癌中HBV和HCV基因和抗原的分布及意义   总被引:1,自引:0,他引:1  
采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细  相似文献   

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For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.  相似文献   

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