简介：INTRODUCTIONSoilacidificationduetoaciddepositionhasbeenoneofthemajorenvironmentalprob-lemsconcernedbysoilscientistsandecologistsfortherecent20years(vanBreemen,1990).SoilacidificationwithamarkedpHdecreaseofforestsoilswithinvarioustimeintervalshasbeenreportedinGermany,Sweden,theNetherlands,AustraliaandtheUnitedStates(van

简介：AchangeintheEuropeanUnionenergypolicyhasmarkedlypromotedtheexpansionofbiogasproduction.Consequently,largeamountsofnutrient-richresiduesarebeingusedasorganicfertilizers.Inthisstudy,apotexperimentwasconductedtosimulatethehigh-risksituationofenhancedgreenhousegas(GHG)emissionsfollowingorganicfertilizerapplicationinenergymaizecultivation.WehypothesizedthatcattleslurryapplicationenhancedCO_2andN_2Ofluxescomparedtobiogasdigestatebecauseoftheoverallhighercarbon(C)andnitrogen(N)input,andthathigherlevelsofCO_2andN_2OemissionscouldbeexpectedbyincreasingsoilorganicC(SOC)andNcontents.Biogasdigestateandcattleslurry,atarateof150kgNH_4~+-Nha~(-1),wereincorporatedinto3soiltypeswithlow,medium,andhighSOCcontents(Cambisol,MollicGleysol,andSapricHistosol,termedClow,Cmedium,andChigh,respectively).TheGHGexchange(CO_2,CH_4,andN_2O)wasmeasuredon5replicatesoveraperiodof22dusingtheclosedchambertechnique.TheapplicationofcattleslurryresultedinsignificantlyhigherCO_2andN_2Ofluxescomparedtotheapplicationofbiogasdigestate.NodifferenceswereobservedinCH_4exchange,whichwasclosetozeroforalltreatments.SignificantlyhigherCO_2emissionswereobservedinChighcomparedtotheothertwosoiltypes,whereasthehighestN_2OemissionswereobservedinCmedium.Thus,theresultsdemonstratetheimportanceofsoiltype-adaptedfertilizationwithrespecttochangingsoilphysicalandenvironmentalconditions.

简介：Thechangeofpinescale(HemiberlesiapitysophilaTakagi)populationdensityonpineforestinurbanparkbetweentreatment(tendingoperations)andCK(notendingoperations)wasresearchedinthispaper.Theresultswereshownasfollows:populationdensitydeclinedto0.63headperbundlefrom2.61headsperbundlewhencrowndensityofpineinurbanparkhadbecome0.5orsobymeansofcultivationactivitiessuchasfelling,pruningandthinningandsoon,anddropgotto75.86percent.Thepinewoodswouldsoongetrevivedonceusingthesecultivationactivities,sotendingoperationswasmainmeasurescontrollingoverharmofpinescaleinurbanpark;Atthesametime,populationdensityofpinescaleonpinewoodsinthesunnyslopewasmorethanthatinthesomberslopeandithadbecomelessandlessfromsunnyslopetosomberslope.Therefore,treespeciesmustbechosenintheplanninganddesignofurbanparkforpreventingharmandhappeningofpinescale.

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简介：1超早断奶简介为了清除猪场的疾病．生产出高度健康的种猪，白50年代早期开始，国外通过从健康的母猪剖腹产取得仔猪。并在隔离状态下饲养出“无特定病原猪（SPF）”，这在控制疾病方面取得了很大的进展，但“无特定病原猪”生产成本、技术要求过高，不能大面积推广。

简介：当你第一眼见到此鱼时．你是否感到异常惊讶？世间居然有如此完美之鱼！这是什么鱼呢？既象红宝石．又象花罗汉！

简介：1Background1.1BasicsituationofstudysiteYao’ancountyislocatedinthenorthwesternpartofcentralYunnanplateau.ItisoneoftheimportantgrainProductionbasecountiesofYunnanProvince.HanandYiarethemainethnicgroupsinthisprovince.BanliuAdministrativeVillagebelongsto...

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简介：“浦江鲫”是舒兰市水产技术推广站从上海市松江区水产良种场引进的一个鲫鱼良种，2003年引进“浦江鲫”乌仔培育苗种，2004年进行商品鱼生产，本文作者之一的陈荣清在亮甲山水库管理局关桥渔场养殖38．5亩“浦江鲫”成鱼，当年获纯利21．3万元，现将生产过程和体会进行归纳总结如下。

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简介：Theannualseriesofδ13CweremeasuredintreeringsofthreeCryptomeriafortuneidisks(CF-1,CF-2,andCF-3)collectedfromWestTianmuMountain,ZhejiangProvince,China,accordingtocross-datingtreeringages.Therewasnoobviousdecreasingtrendoftheδ13CannualtimeseriesofCF-2before1835.However,from1835to1982thethreetreeringδ13Cannualseriesexhibitedsimilardecreasingtrendsthatweresignificantly(P≤0.001)correlated.Thedistributioncharacteristicsofascatterdiagrambetweenestimatedδ13CseriesofCF-2frommodelingandtheatmosphericCO2concentrationextractedfromtheLawDomeicecorefrom1840to1978wereanalyzedandacurvilinearregressionequationforreconstructingatmosphericCO2concentrationwasestablishedwithR2=0.98.Also,atestofindependentsamplesindicatedthatbetween1685and1839thereconstructedatmosphericCO2concentrationusingtheδ13CseriesofCF-2hadacloserelationshipwiththeLawDomeandSipleicecores,withastandarddeviationof1.98.ThegeneralincreasingtrendofthereconstructedatmosphericCO2concentrationcloselyreflectedthelong-termvariationofatmosphericCO2concentrationrecordedbothbeforeandaftertheIndustrialRevolution.Between1685and1840theevaluatedatmosphericCO2concentrationwasstable,butafter1840itexhibitedarapidincrease.Givenalongerδ13Cannualtimeseriesoftreerings,itwasfeasibletorebuildarepresentativetimeseriestodescribetheatmosphericCO2concentrationforanearlierperiodandforyearsthatwerenotintheicecorerecord.

简介：Background:Forestmanagementstrategiessuchasthinninghavelongbeenusedtoenhanceecosystemfunctions,especiallyinplantations.Thinninginplantationswithhighdeerdensity,however,maynotyieldadesiredincreaseinunderstoryvegetationbecausedeergrazeongerminatingplantsafterthinning.Here,weexaminethechangesinunderstoryvegetationafterthinninginplantationsthathavebeenovergrazedbysikadeertoprovideinsightintotheeffectsofthinningonecosystemfunctionssuchassoilconservationandbiologicaldiversity.Methods:WeconductedoursurveyintheTanzawaMountainsofeasternJapan.Wesurveyedthechangeinunderstoryvegetationwithinandoutsideofthreedeerexclosuresonasingleslopewiththreelevelsofunderstoryvegetationcover:sparse(1%,exclosure'US'),moderate(30%,exclosure'MM'),anddense(80%,exclosure'LD')over10yearsaftera30%thinningofanold-growthcedarandcypressplantationwhichwasovergrazedbysikadeer.Results:Understoryvegetationcover,biomassandspeciesrichnessincreasedwithinandoutsidethe'US'and'MM'exclosuresafterthinning,andbiomasswasgreaterwithinthanoutsidetheexclosuresat10yearsafterthinning.Unpalatablespeciesdominatedboth'US'and'MM'exclosuresbeforethinning,andtreesandshrubsdominatedwithintheexclosuresovertimeafterthinning.Incontrast,unpalatable,grazing-tolerant,perennial,andannualspeciesincreasedoutsidethe'US'and'MM'exclosures.Nonoticeablechangeswereobservedwithinandoutsidethe'LD'exclosurewhencomparedwiththe'US'and'MM'exclosures.Conclusions:Ourresultssuggestthatthinningastandby30%basedonvolumeresultedinanincreaseinunderstoryvegetationcovermainlycomposedofbothunpalatableandgrazing-tolerantspeciesinaplantationforestwhereunderstoryvegetationissparseormoderateandsikadeerdensityishigh.Weemphasizethatestablishingdeerexclosuresorcontrollingdeerisessentialtomaintainingsimilarunderstoryvegetationbothwit

简介：食品超微粉碎技术是近年发展起来的采用现代物理或化学方法对材料进行微粉化的一种新手段,是传统工艺改进、新产品开发的推动力。目前日本、美国市场上销售的果味凉茶和冻干水果粉等都是应用超微粉碎技术加工制成的。粉碎是用机械力的方法来克服固体物料内部的凝聚力而使之破碎的单元操作。粒度是指物料颗粒的大小,是粉碎程度的代表性尺寸。根据被粉碎物和成品粒度的大小,粉碎可分为粗粉碎、中粉碎、微粉碎和超微粉碎等4种。其中,超微粉碎（超细粉碎）是指原料粒度为0.5mm~5mm,成品颗粒粒度为10μm~25μm。

简介：浙江依靠“早”、“实”、“超”三字经，使《国土绿化》杂志发行工作走在了全国前列。希望其它单位借鉴浙江经验，做好《国土绿化》杂志的宣传、广告和发行工作。

简介：礼泉超红葡萄自2016年通过审定以来,因其生长势强、丰产、果穗果粒大、果实色泽靓丽、耐贮运、栽培效益高等优点,而受到果农的高度关注。现将其配套栽培技术总结如下。1园地选择该品种在排水良好的沙壤土、黄绵土和垆土中均能正常生长;坡地建园以小于25°背风向阳的东坡或南坡梯田为佳。

简介：今年7至8月份，山东省青岛市食品安全办公室邀请市民代表一起抽检了10种上千批次食品进行检测。9月3日，青岛市食安办首先发布了市民关注度最高的“生鲜肉”检测，

简介：通过对超掺量粉煤灰混凝土在工程中应用研究的实践，和对超掺量粉煤灰混凝土配制等方面的控制措施介绍，论述了运用各项检测数据证明超掺量粉煤灰混凝土的优势。

简介：据部分调查表明,绝大部分用运输车的机油消耗都严重超过标准。正常的机油耗量应为主燃量的2％～3％;而且目前的消耗大都在8％-10％,最高的达15％,最低也在5％左右。并且机油超耗的顽症有增无减。

简介：2006年3月20日，无极县吕吕村养鸡户吕某饲养的700只60日龄的海兰灰青年鸡，在注射Ⅰ系疫苗时，由于用最过大，700只鸡死亡了358只，现将发病情况报告如下。