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251.
对生长在柽柳荒漠生境中最常见的4种早春短命植物离子草(Chorispora tenella (Pall.) DC.)、角果毛茛(Ceratocephalus testiculatus (Crantz) Bess.)、东方旱麦草(Eremopyrum orientale (L.) Jaub et. Spash)和弯果婆婆纳(Veronica campylopoda Boiss.)进行取样调查, 分析了柽柳灌丛下和灌丛外的4种植物丛枝菌根(AM)的形成状况、根际AM真菌的孢子密度和群落组成, 并探讨了柽柳灌丛对其菌根侵染状况、根际AM真菌群落组成的影响. 结果表明, 柽柳灌丛下短命植物的侵染率和根际土壤中AM真菌孢子的密度显著低于灌丛外的植物, 并且灌丛下AM真菌的种类(12种)少于灌丛外(19种). 灌丛下短命植物根际土壤由于受到柽柳灌丛的影响, 其养分含量除速效钾外, 都高于灌丛外; 灌丛下碱解氮和速效磷的含量分别为65.37和44.50 mg/kg, 而灌丛外的含量则为32.33和33.85 mg/kg. 本研究共从短命植物根际分离到21种AM真菌, 其中无梗囊霉属有5种、原囊霉属1种、球囊霉属13种和类球囊霉属2种. 通过上述结果得出以下结论: 柽柳灌丛影响着土壤的理化特性及其下生长的短命植物丛枝菌根的形成和根际AM真菌群落的组成. 相似文献
252.
Comparative analysis of A,B,C and D genomes in the genus Oryza with C_0t-1 DNA of C genome 总被引:1,自引:0,他引:1
LAN Weizhen* QIN Rui * LI Gang & HE Guangcun. Key Laboratory of State Ethnic Affairs Commission for Biological Technology College of Life Sciences South-Central University for Nationalities Wuhan China . Key Laboratory of Ministry of Education for Plant Developmental Biology College of Life Sciences Wuhan University Wuhan China 《科学通报(英文版)》2006,51(14)
The genus Oryza includes two cultivated species, O. sativa L. and O. glaberrima Steud. and comprises more than 20 species[1]. The genomes of Oryza are classified into 10 types: AA, BB, CC, BBCC, CCDD, EE, FF, GG, HHJJ and HHKK[2,3]. Morphological variatio… 相似文献
253.
JIAO Minghai~ YAN Ping~ JIANG Huiyan~ .Computer Center Northeastern University Shenyang Liaoning China .School of Information Science Engineering Northeastern University Shenyang Liaoning China 《武汉大学学报:自然科学英文版》2006,11(5):1065-1068
0 IntroductionThe useful texts information in the Web is analyzed bythe method of Web information retrieval according tothe requirement of the user . To get the information of citingtexts and relative key words fromthe Web,we can searchforlots of correlativeinformation data storedinthe Web databaseby Webinformationretrieval .This paper appliedthe method-ology of data mining to Web information retrieval since thepurpose of data miningisto discover thefrequent patternfromthe Web.Alot of studi… 相似文献
254.
Microbial starch-binding domains (SBD) and granule-bound starch synthase I (GBSSI) are proteins which are accumulated in potato starch granules. The efficiency of SBD and GBSSI for targeting active luciferase reporter proteins to granules during starch biosynthesis was compared. GBSSI or SBD sequences were fused to the N- or C-terminus of the luciferase (LUC) gene, via an artificial Pro-Thr encoding linker sequence. The genes were introduced into an amylose-free (amf) potato mutant. It appeared that SBD was superior to GBSSI as a targeting sequence, mainly because the luciferase retained higher activity in the SBD-containing fusion proteins than in the GBSSI-containing ones. 相似文献
255.
QIAN Shahua~ LUO Yan~ MO Shaobo~ WENG Yue~ . College of Resources Environmental Sciences Wuhan University Wuhan Hubei China . College of Chemistry Molecular Sciences Wuhan University Wuhan Hubei China 《武汉大学学报:自然科学英文版》2006,11(2):437-440
0Introduction Vanadiumplaysanimportantroleinmodernindustry,es peciallyinsteelandchemicalindustry.Forinstance,itscompoundsarewidelyappliedintheproceduresofvitrioland petroleumchemicalmanufactureascatalyzers[14].Vanadium hasseveralvalences,butgenerallyitslowvalencesturnintohighoneseasilyinenvironment[5].BecauseV(Ⅴ)isthemost stableandpoisonousone,weoftenlayemphasisonitinenvi ronmentalpollutioncontrol.Vanadiumexistsinenvironmentalwaterwithextremelylowconcentration.Inseawateritscontentislessthan… 相似文献
256.
LIU Jianzhong~ ZHANG Yiling~ . College of Chemical Engineering Technology Wuhan University of Science Technology Wuhan Hubei China . College of Animal Science Technology Northwestern University of Science Technology in Agriculture Forest Yangling Shannxi China 《武汉大学学报:自然科学英文版》2006,11(2):447-450
0Introduction Afterthecarryingoutofopen doorpolicies,espe ciallyinthelatesttenyears,livestockandpoul try’sraisingbusinessdevelopedveryfastinChina,whichhelpeduscompletelyshrugofftheembarrassed situationofsevereshortagesofanimalproteininthepastlongperiodandgreatlyexcitedandencouraged us.Meanwhilewemustclearlyrealizethepotentialdangersbehindthepresentprosperities.Ourbreeds arebecominglessandless,manynativebreedswithlowperformancedisappearedcompletely,thetendency oftheirextinctionisincreasinginth… 相似文献
257.
Ground granulated blast furnace slag(GGBFS)and steelmaking slag have been used as a raw material for cement production or as an aggregate to make concrete,which contribute aluminum,calcium,iron,and silicon oxides.The suitability of the slag for a particular application depends on its reactivity,cost,availability,and its influence on the properties of the resulting concrete.For the interest of durability studying of concrete in the presence of slag,the accelerated carbonation products and leaching behavior of the slag and Portland cement(PC)were studied.The experimental results confirmed that the slag was more resistant to carbonation compared to PC.The carbonation degree of GGBFS reduced by 17.74%;and the carbonation degrees of steelmaking slags reduced by 9.51%-11.94%.Carbonation neutralized the alkaline nature of the hydrated pastes and gave rise to the redox potential of the leachate slightly(30-77 mV).The carbonation also increased the release of most of the elements presented,except for calcium,to the aqueous environment.It is concluded that blend cements(PC plus slag)have economical advantages and better durability compared to PC. 相似文献
258.
政策制订者需要短期气候预报来就典型的 2 0年规划远景制订对付气候变化的策略 ,有两项新的研究增加我们对这些气候预报的信心 相似文献
259.
260.
早-中元古代Columbia超级大陆研究进展 总被引:17,自引:1,他引:17
地球在过去25亿年里曾发生过几次全球性大规模碰撞造山事件(如 Grenville事件,Pan-African事件等);地质学家由此推测大陆块自早元古代以来曾发生过周期性拼合和分离,从而导致古超级大陆的形成和裂解[1].在过去10年里(1991~2001年),被认为由约1.0 Ga Grenville造山事件所形成的超级大陆Rodinia已成为古大陆重建的一个热点[2,3].然而,地质学家们在重建Rodinia 过程中发现,并非全部Rodinia组成陆块都是由Grenville造山带所焊接,而 相似文献