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1.
湿地的定义和类型划分   总被引:36,自引:2,他引:34  
湿地的定义和类型划分刘厚田(中国环境科学研究院北京100012)DefinitionandClassificationotWetlands.¥LiuHoutian(ChineseAcademyofEnvironmentalsciences,Beiji...  相似文献   

2.
洞庭湖滨湖湿地平原农村生态工程初步研究严斧,游有林,刘劲凡,卢源德,周为民(中国科学院生态环境研究中心系统生态室沅江课题组,大庸市416600)RuralEcologicalEngineeringonWetlandPlainofDongtingLakeside¥.YanFu;YouYoulin;LiuJinfan;LuYuande;ZhouWeimin(YuanjiangResearchGroup,ResearchCenterforEco-environmentalScience,A-cademiaSinica,Dayong416600).ChineseJournalofEcology,1993,12(2):45—48.AccordingtothemaintypesofresourcecombinationsonwetlandplainofDongtinglakeside,severaleco-logicalengineeringsincludinglakesidereed-forest,lowlandrice-fish-ramie,rnanure-forage-fuel,fish-pig-duckandf  相似文献   

3.
从第五届国际湿地会议看湿地保护与研究趋势   总被引:61,自引:5,他引:56  
从第五届国际湿地会议看湿地保护与研究趋势王仁卿刘纯慧晁敏(山东大学生命科学院生物系,济南250100)WetlandConservationandAdvancesDerivedfromthefifthInternationalWetlandsConf...  相似文献   

4.
梁宗琦  刘爱英 《真菌学报》1996,15(4):264-271
本文报道采用贵州省宽阔水自然保护区的9种虫草,它们是多壳虫草新咱(CordycepspolycarpicaLiang&Liusp.nov),鼠尾虫草新种(CordycepsmusicaudataLiangetLiusp.nov)针孢虫草(CordycepsacicularisRev.exBerk.)罗伯茨虫草(Cordycepsrobertsii(Hook),Gray)下垂虫草(Cordyceps  相似文献   

5.
我国南海海龟资源的调查与保护研究现状与展望王亚民(中华人民共和国农业部水产司,北京100026)AchievementandPerspectiveoftheResearchesonSoutbChinaSeaTurtleResourcesandProtectioninCbina¥WangYamin(DivisionofScienceandTechnology,DepartmentofFishery,People’sRepublicofChinaMinistryofAgriculture,Beijing100026).ChineseJournalofEcology,1993,12(6):60-61.ThispaperintroducestheresearchesinfieldofSouthChinaSeaturtleresourcesandprotectioninChina.TherearefivespeciesseaturtlesinChina,about90%ofthemliveinSouthChinasea。During1959-1988,3184.Itseaturtlewerecatched(about  相似文献   

6.
湖北省吨粮田的现状及其投肥效率分析孙先(华中农业大学,武汉430070)CurrentSituationandFertilizationEfficiencyofHighProductiveCroplandsinHubeiProvince¥SunXian-rong(CentralChinaAgricultureUniversity,Wuhan430070).ChineseJournalofEcologyl1993,12(2):55-56.Since1990,thedevelopmentofhighproductivecroplandhasbeenacceleratedandtheeffectofitsyieldandbenefitincreaseisveryobvious,But,whetherhighyieldandhighefficiencycanbesynchronizedde-servescloseattention,Inthisresearch,79highyieldcroppingpatternsareinvestigatedforthreeyearsinHubeiandtheirefficien  相似文献   

7.
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   

8.
ConformationalStudiesofArabinoglucuronomannology(AGM)ImshikLee;BaiChunli;WangChen(InstituteofChemistry,ChineseAcademyofScienc...  相似文献   

9.
农业生态学在我国发展的回顾与展望   总被引:5,自引:0,他引:5  
农业生态学在我国发展的回顾与展望骆世明(华南农业大学,广州510642)ReviewandPerspectiveonDevelopmentofAgroecologyChina.¥LuoShiming(SouthChinaAgriculturalUniversity,Guangzhou510642).ChineseJournalofEcology,1993,12(2):4-6.Inlastdecade,greatprogresshasbeenmadeintheteachingandresearchofagriculturalecologyinChi-na,butsomeobstaclesstillexistonhowtounderstandagroecology.Ifwecanrecognizethesocialde-mandofagroecologyanditspositioninagriculturalscienceandpayattentiontothedescription,assess-ment,experimentandanalysisofagroecosystemmodels,thequanti  相似文献   

10.
沈阳水资源保护与水质管理李秀鸿(沈阳环境科学研究所,110005)WaterResourceConscrvancyandWaterQualityControlinShenyang¥LiXiouhong(ShenyangInstituteofEnvironmentalscieilce,110005).(ChineseJournalofEcology,1993,12(5):45-48。Theoverallandlongtermimpactsofwaterresourceshortageandwaterpollutiononeconomicdevelop-ment,humanlifeandecologicalenvironmentinShenyangarediscussedinthispaper.Itispointedoutthatinordertosolvetheseproblems,areasonablecontrolpolicyandcorrespondingtechnologymustbeadoptedincombiningwiththedevelopmentandConservancyofexistin  相似文献   

11.
The functional properties of the anaerobic responsive element (ARE) of the maize Adh1 gene have been analysed using a transient expression assay in electroporated maize protoplasts. The ARE functions in both orientations although inversion of the ARE sequence relative to the TATA box element produces slightly weaker promoter activity under anaerobic conditions and elevated expression under aerobic conditions. Promoter activity under anaerobic conditions is proportional to the number of complete ARE sequences in the Adh1 promotor. The ARE contains two sub-regions and dimers of sub-region II are as efficient as the wild-type sequence in activating gene expression under anaerobic conditions. However, sub-region I dimers do not appear capable of inducing gene expression in response to anaerobic stress. We conclude that sub-region II is essential for anaerobic induction of gene expression. Reporter gene expression remains constant when the spacing between sub-regions of the ARE is increased up to at least 64 bp, but increased spacing of 136 bp or greater abolishes expression in both aerobic and anaerobic conditions, indicating that a close association of the two sub-regions is required both for anaerobic responsiveness and for maximal levels of aerobic gene expression. When the ARE is placed upstream of position –90 of the CaMV 35S promoter, the ARE produces a high level of expression in both aerobic and anaerobic conditions. The general enhancement of gene expression driven by the hybrid ARE/35S promoter in aerobic conditions requires an intact sub-region II motif since mutation or deletion of sub-region II from the hybrid promoter reduces the level of expression to that observed for the truncated 35S promoter alone. In addition, mutation of the sub-region I sequences in the ARE/35S hybrid promoter does not significantly reduce expression in aerobic conditions, relative to pARE/35S(-90), suggesting that sub-region I does not contribute to this general enhancer function.  相似文献   

12.
厌氧颗粒污泥(anaerobicgranularsludge,AnGS)是由多种功能微生物组成的自固定化聚集体,具有容积负荷高、工艺简单、剩余污泥产量低等优点,在废水处理领域中显示出巨大的技术和经济潜力,被认为是一种很有前景的低碳废水处理工艺。本文系统总结了近年来厌氧颗粒污泥微生物结构和功能的研究成果,从微生物学角度讨论了厌氧颗粒污泥形成及稳定的影响因素,并对今后厌氧颗粒污泥的研究进行了展望,以期为后续厌氧颗粒污泥技术的深入研究和实际工程应用提供参考。  相似文献   

13.
Longterm performance and stability of two upflow anaerobic sludge blanket (UASB) reactors inoculated with granular sludge and treating a synthetic waste water containing pentachlorophenol (PCP) and phenol were studied. A similar system consisting of two fixed-film reactors inoculated with anaerobic digested sewage sludge were further studied. One reactor in each series received glucose in addition to the phenols. Dechlorination of PCP proceeded via two different dominating pathways in the respective reactor systems, suggesting that two distinct microbial populations were present, probably originating from the different inocula. Dechlorinating activity was maintained for more than 18 months in the UASB reactors and was generally higher than in the fixed-film reactors. In the fixed-film reactors, dechlorination of PCP suddenly decreased after 15.5 months of operation compared to earlier performance. Since no operational parameters had been changed, this indicated that the enriched culture was unstable on a longterm basis. Addition of yeast extract to the medium restored activity. General process stability in both reactor systems was clearly enhanced by the addition of glucose and was superior in the UASB/granular sludge system. The better performance and the higher stability in the UASB/granular sludge reactor highlights the importance of thorough screening of inocular prior to start-up of processes treating waste waters containing xenobiotic compounds.Abbreviations PCP pentachlorophenol - TeCP tetrachlorophenol - TCP trichlorophenol - DCP dichlorophenol - UASB upflow anaerobic sludge blanket - HRT hydraulic retention time  相似文献   

14.
从64只感染根管中的58只根管分离到144株无芽胞厌氧菌,其中类杆菌54株,厌氧性链球菌23株,韦荣氏球菌17株,真杆菌11株,梭杆菌10株,放线菌8株,双岐杆菌2株,消化链球菌和消化球菌19株。40只根管为厌氧菌和兼性厌氧菌或需氧菌混合感染,18只根管和6只根管分别为单独厌氧菌和兼性厌氧菌感染。33只根尖周炎根管分别采集牙髓和根尖渗出物样本进行培养,实验结果表明牙髓样本中革兰氏阳性厌氧杆菌检出率较高,根尖渗出物中以产黑素类杆菌属的细菌检出率较高。根尖周炎和牙槽脓肿患者的感染根管中产黑素类杆菌属的细菌检出率明显高于蜂窝组织炎患者。  相似文献   

15.
硫酸盐还原菌的分离纯化方法   总被引:3,自引:0,他引:3  
硫酸盐还原菌在硫元素的地球生物循环及环境保护中都发挥着重要作用。介绍了硫酸盐还原菌的分离与纯化的方法,比较了厌氧袋、厌氧罐、厌氧工作站、厌氧管等方法的应用,以及在使用中需要注意的问题;同时介绍了分子生物学技术在硫酸盐还原菌分离纯化方面的应用,旨在为硫酸盐还原菌的分离纯化提供一定的参考依据。  相似文献   

16.
Abstract A bank of 5000 random gene fusions to lacZ was screened for amino acid auxotrophs and for gene fusions in which β-galactosidase was only expressed anaerobically. Since the number of genes involved in the synthesis of amino acids is known, estimation of the number of anaerobically regulated genes is possible. This estimate that Escherichia coli contains about 50 anaerobically induced genes, is somewhat larger but of the same order as the number of anaerobically induced polypeptides seen on the 2-D gels of Smith and Neidhardt.  相似文献   

17.
Aims: To investigate the influence of aerobic or vacuum pack storage of beef trimmings on the microbiology, colour and odour of subsequently produced mince. Methods and Results: Trimmings stored aerobically for 7 or 10 days and in vacuum packs for 7, 10, 14 or 22 days at 0 or 5°C were minced, stored aerobically at 0 or 5°C for up to 7 days and examined daily to determine Total viable, Pseudomonas, Lactic acid bacteria, Brochothrix thermosphacta, and Enterobacteriaceae counts, colour and odour. Mincing reduced counts, particularly of Pseudomonas, B. thermosphacta and Enterobacteriaceae, probably because of the action free radicals released from muscle and bacterial cells. Storage of vacuum‐packed trimmings for 22 days resulted in improved mince colour and inhibition of the growth of Pseudomonas. Conclusions: The shelf life of mince from trimmings is directly influenced by the trimmings storage conditions, and longer‐term vacuum storage of trimmings produced improvements in mince quality. Significance and Impact of the Study: There appears to be no scientific rationale for limiting the storage of vacuum packaging beef trimmings to 15 days, prior to mince production, as stated in EU 835/2004. This study identifies advantages in storing trimmings in vacuum packs for at least 21 days prior to mincing, in terms of improved mince quality.  相似文献   

18.
19.
Abstract Experiments were carried out with slurries of saltmarsh sediment to which varying concentrations of nitrate were added. The acetylene blocking technique was used to measure denitrification by accumulation of nitrous oxide, while reduction of nitrate to nitrite and ammonium was also measured. There was good recovery of reduced nitrate and at the smallest concentration of nitrate used (250 μM) there was approximately equal reduction to either ammonium or nitrous oxide (denitrification). Nitrite was only a minor end-product of nitrate reduction. As the nitrate concentration was increased the proportion of the nitrate which was denitrified to nitrous oxide increased, to 83% at the greatest nitrate concentration used (2 mM), while reduction to ammonium correspondingly decreased. This change was attributed either to a greater competitiveness by the denitrifiers for nitrate as the ratio of electron donor to electron acceptor decreased; or to the increased production of nitrite rather than ammonium by fermentative bacteria under high nitrate, the nitrite then being reduced to nitrous oxide by denitrifying bacteria.  相似文献   

20.
在青藏高原地区的低温条件下通过滚管技术分离了一类耐低温产甲烷菌,并利用气相色谱法测定了产气活性。结果表明:这类甲烷菌最低产气温度为8℃,甲烷气体产生的高峰期在厌氧培养的第7 d;pH值与盐浓度对其产气活性均有影响,最佳条件为pH值7.0、盐度4%。  相似文献   

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