简介:Heterosisistheuniversalphenomenainnature,anditsformationmechanismhasbeenthefocusofresearch.Onthisbasis,anumberoftheoreticalhypotheseshavebeenproposedforthereasonofheterosis,suchasthedominancehypothesis,epistaticeffect,generegulationnetworks,etc.Forthepastyears,manyresearchershaveattemptedtoelaboratethemechanismofheterosisatphysiological&biochemicallevelandmolecularlevel.Theresultsshowedheterosisplantshaveastrongerphotosyntheticcapacity,relativelywell-developedtissuesandgreateradaptionandbufferingabilitytoexternalenvironment.Theheterosisisoftenmorepronouncedinrelativelylowlight,lowtemperatureandlowCO2concentration.Inaddition,geneticdistance,differencesingeneexpressionandDNAmethylationareallcloselyrelatedwithheterosis.Thisstudyreviewedresearchresultsofforestryandagriculture,anddiscussedthefutureresearchdirectionofthisfield.
简介:Thepaperanalyzedthebottlenecksofinternationalforestfinancingdevelopmentfromtheperspectiveofthedevelopmentstateofforestfinancingmechanism.Italsoanalyzedthedevelopmentpossibilitiesofemergingfinancingchannelswhileintroducingofficialdevelopmentassistanceandnon-financialdevelopmentassistanceintheframeworkofinternationalforestfinancingmechanism,andpooledthevariousexistingforest-involvedfundstoproposeafeasiblearchitecturedirectionforpossiblefuturedevelopment.
简介:Globalwarmingisoneofthehottestenvironmentproblems.OneofthereasonsisthesharpincreaseofCO2inatmosphere.Soilrespirationinforestecosystemsaccountsto60%-90%oftotalecosystemrespirationandisthereforeoneofthekeycomponentsoftheglobalCcycle.Thispapersummarizeddifferentresponsesofsoilrespirationtoforestmanagementmeasures,anddescribedtherelevantresearchesathomeandabroadontheeffectofmanagementmeasureslikeharvesting,forestfertilization,soilimproving(Liming),litterremoval,andprescribedburningonsoilrespiration.
简介:Thepaperelaboratesindetailscertificationmechanismforsustainableforestmanagement,includingthedefinition,contents,objectives,costs,benefits,characteristics,proceduresandimpactsofcertificationaswellasmaincertificationsystems.ItalsointroducesindetailsthelatestprogressanddevelopmentperspectivesofcertificationinChinaandaroundtheworld.Certificationisamarket-basedmechanism,whichaimsatenhancingandstrengtheningthereasonableutilizationofforests.Itusua...
简介:Groundfireisanignitingphenomenonthatisdifficulttocontrolandlightningisthemaincauseofgroundfire.Themechanismoflightning-groundfireisverycomplex.Daxing'anlingMountainsforestregionistheplacethatlighting-groundfireoccursmoreoftenandregularly.Ourstudyonlightning-groundfireofthiszonein2002shows:muchmoresoilnearthesurfaceandthegroundfuelisthematterpreconditionsoflightning-groundfire,andtheweatherconditionshastentheoccurrenceoflightning...
简介:以杭州曲院风荷景点为研究对象,以历史文献为线索,结合山水画、版画、照片、测绘图等图像资料,梳理其景观格局变迁历程,分析演变中景物间的联系,并对各时期园林发展情况进行总结。将其发展历程划分为南宋麯院时期、元代至明代衰落时期、清代更址重建时期及中华人民共和国成立至今的公园化时期。认为清康熙年间曲院的迁址与更名是景点发展的重要转折点,这一举动既使古老的景名得以延续,又使景点有了新的内涵和发展空间。园林建筑与环境的营造围绕"曲"这一主题展开,代表人工的"曲院"与代表自然的"风荷"体现了该景点人工建筑与自然景物并重的审美主旨。通过分析整理历史图像资料对于今人了解古代园林变迁有重要帮助。