简介：ＦＲＯＭＷＯＭＥＮ＇ＳＭＯＵＮＴＡＩＮＰＲＯＤＵＣＴＩＯＮＢＲＩＧＡＤＥＳＴＯＷＯＭＥＮ＇ＳＴＲＥＥＦＡＲＭＳ￥ＢｙＸｉｅＪｉｎｇｘｉａｎｇＹｏｕｘｉｃｏｕｎｔｙｉｓｓｉｔｕａｔｅｄｉｎａｍｏｕｎｔａｉｎｏｕｓ，ｐｏｏｒｌｙｆｏｒｅｓｔｅｄｒｅｇｉｏ...

简介：Availablewaterandfertilizerhavebeenthemainlimitingfactorsforyieldsofspringwheat,whichoccupiesalargeareaoftheblacksoilzoneinnortheastChina;thus,theneedtosetupappropriatemodelsforscenarioanalysisofcroppingsystemmodelshasbeenincreasing.ThecapabilityofCropSyst,acroppingsystemsimulationmodel,tosimulatespringwheatgrowthofawidelygrownspringcultivar,'Longmai19',intheblacksoilzoneinnortheastChinaunderdifferentwaterandnitrogenregimeswasevaluated.Fielddatacollectedfromarotationexperimentofthreegrowingseasons(1992-1994)wereusedtocalibrateandvalidatethemodel.Themodelwasrunfor3yearsbyprovidinginitialconditionsatthebeginningoftherotationwithoutreinitializingthemodelinlateryearsintherotationsequence.CropinputparametersweresetbasedonmeasureddataortakenfromCropSystmanual.Afewcultivar-specificparameterswereadjustedwithinareasonablerangeoffluctuation.TheresultsdemonstratedtherobustnessofCropSystforsimulatingevapotranspiration,abovegroundbiomass,andgrainyieldof'Longmai19'springwheatwiththerootmeansquareerrorsbeing7%,13%and13%oftheobservedmeansforevapotranspiration(ET),grainyieldandabovegroundbiomass,respectively.AlthoughCropSystwasabletosimulatespringproductionreasonablywell,furtherevaluationandimprovementofthemodelwithamoredetailedfielddatabasewasdesirableforagriculturalsystemsinnortheastChina.

简介：FieldstudieswereconductedintheJiuwantanForestFarm,HuaduDistrictofGuangzhouCityfromJune2004toMarch2006toevaluatetheeffectsofplantingspacings(0.5m×0.5m,0.5m×1.0mand1.0m×1.0m)anddifferentfertilizers(bio-fermentedmanure,NPKcompoundfertilizerandNPKmixedfertilizer)onthegrowthofDaemonoropsmargaritaegrownunderirrigationandfull-lightconditionsforedibleshootsproduction.Theeffectsofapplicationofdifferentfertilizersonthemeanheight,lengthofstem...

简介：持续农业生产具有到食物供应安全的重要重要性。这研究试图在北方中国平原(NCP)并且随后在县规模调查庄稼收益反应到土壤质量的空间可变性导出关键土壤质量指示物。土壤样品从表面(020厘米)在2008引用geo、拿并且表面下(2040厘米)在整个Fengqiu县的132块地里的层，在NCP的中心定位了，为随后的土壤性质的分析。年度庄稼收益从土壤样品是镇定的一样的领域被获得。土壤质量与13个土壤性质基于一个模糊集合被评估，并且它的空间分布被集成geostatistical分析和地理信息系统(GIS)调查技术。土壤质量索引被分类进五个等级，并且他们的空间分布在县以内被印射。表面土壤质量比表面下的土壤高是大约一～二个等级。质量索引因为表面和表面下的土壤断然与年度庄稼收益被联系，建议两个的重要性。土壤有机物，全部的氮，可得到的P，和可得到的K贡献了50%联合重量到土壤质量索引并且以可持续性在区域作为土壤质量地位的关键指示物被识别。

简介：在南部的中国的大米小麦旋转被经常的排干洪水的水政体和重氮(N)授精描绘。有进溶解的器官的氮的行为的研究的实质的缺乏(穿上)在强烈地管理的agroecosystem。在situ地实验3年的A被进行决定穿上沥滤并且它在6个连续大米/小麦季节由授精，灌溉和降水影响了的季节、每年的变化。在常规N实践下面(300kgN哈为米饭和200kgN的−1哈为小麦的−1)，季节的一般水准在leachate(100厘米土壤深度)穿上集中因为三个米饭和小麦季节是0.6–1.1和0.1–2.3mgNL−1,分别地。累积穿上沥滤被估计是1.1–2.3kgN哈为米饭季节和0.01–1.3kgN的−1哈为小麦季节的−1，与1.1–3.6kg的一个年度总数N哈−1。在大米季节，N化肥有小效果(P>0.05)在上穿上沥滤；降水和灌溉进口了3.6–9.1kgN哈−1穿上，它可以因此隐藏授精效果在上穿上。在小麦季节，N授精有积极效果(P<0.01)在上穿上。不过，这提升效果被可变降水强烈影响，它也带了1.8–2.9kgN哈−1穿上进地。尽管有到使用的化学N和大变化的一个很小的比例，走水路驾驶政体，穿上沥滤必然与另外的自然生态系统相比由于它的相对更大的数量在大米小麦旋转涉及综合的地N预算。

简介：Nitrogen(N)lossesfromammoniumbicarbonateorureaappliedtowheatandthenfollowedimmediatelybyirrigationwereinvestigated.Ammoniavolatilizationwasdeterminedbyamicrometeorologicalmethod(ammoniasampler),totalNlosswasestimatedbythe^15Nmassbalancemethod,anddenitrificationlosswasmeasuredbythediferencemethod(calculatedfromthedifferencebetweenthetotalNlossandammonialoss)andadirectmethod(measuringtheemissionof(N2+N2O)-^15N).Totalammonialossesfromammoniumbicarbonateandureain33dayswere8.7%and0.9%oftheappliednitrogen,respectively.ThecorrespondingtotalNlosseswere21.6%and29.5%,Apparentdenitrificationlosses(bythedifferencemethod)wereratherhigh,being12.9%fromammoniumbicarbonateand28.6%fromurea.However,noemissionof(N2+N2O)-^15Nwasdetectedusingthedirectmethod.

简介：Asequentialextractionmethodforthefractionationofphosphorus(P)inlakesedimentswasusedtoanalyzephosphorusfractionsofsedimentstakenfromthreelarge,shallow,eutrophicfreshwaterlakesofChina-TaihuLake,ChaohuLake,andLongganLake.AllthreelakesarelocatedinthelowerreachesoftheChangjiangRiver(YangtzeRiver).InTaihuLakeandChaohuLake,algaebloomsoccurredeveryyear,whileLongganLakewasamacrophyte-dominatedlake.Resultsshowedthatexchangeablephosphorusfractionsweremuchhigherintheeutrophiclakesedimentsthaninthemacrophyte-flourishinglakesediment.Also,theratioofFe:Pinthesedimentsofthealgae-predominantlakeswasgenerallymuchlowerthanthatinthemacrophyte-predominantlakes.Thus,thegeochemicalfractionsofphosphorusinsedimentshadacloserrelationshipwiththetypeofaquaticvegetation.

简介：Astudyonbalancedfertilizationwasconductedbymeansoflong-termfieldexperiments,andaconve-nienttableforbalancedfertilizationwascompiled.Theexperimentalresultsabouttheeffectoffertilizationonwateruseefficiencyofuplandwheatshowedthattheinputofinorganicfertilizershouldbereducedindryyears.

简介：ＧＲＥＥＮＭＥＳＳＥＮＧＥＲ──ＷＯＭＥＮ’ＳＭＯＵＮＴＡＩＮＰＲＯＤＵＣＴＩＯＮＢＲＩＧＡＤＥＩＮＹＯＵＸＩＶＩＬＬＡＧＥＢｙｐｒｏｊｅｃｔｔｅａｍ“ＷｏｍｅｎａｎｄＳｏｃｉａｌＦｏｒｅｓｔｒｙ”Ｗｏｍｅｎｉｎｍｏｕｎｔａｉｎｏｕｓａｒｅａｓｗａｒ...

简介：Thisworkwasundertakentoresearchorganicwood-flourputtyaswoodensurfaceundercoat.Fourtypesofwood-flour(300,500,800and1000mesh)werepreparedthroughthetechnologicalprocessesofshattering,coarsegrindingandfinegrinding.Andlatex(16%ofsolidcontent)andtwokindsofagents(AandB)wereaddedintotheputty.Inthisexperiment,effectsofagentandparticlesizeofwood-flouronpropertiesoforganicwood-flourputty,suchaspaintingproperties,waterresistance,andabrasive...

简介：Inrecentyears,thequantityandqualityofglobalforestresourcesaredecliningcontinually.Contrarily,thebothinChinaareincreasing,whichisdeeplyrelatedtothesustainableforestmanagementandeco-systemmanagementinChina.Withthetrendthatworldcommunityknowsmoreabouttheimportantroleofforest,moreandmorefunctionsofforestarerecognized.TheimpactandfunctionsofChina'sforestrydeservemoreconcern.Basedonsomeexperiencesinthefieldofforestryresearch,theauthors...

简介：ＤｉｓｃｕｓｓｉｏｎｏｆＸｉｘｉａ’ｓＦｏｒｅｓｔｒｙＡＭｏｄｅｌｆｏｒｔｈｅＤｅｖｅｌｏｐｍｅｎｔｏｆＣｈｉｎａ’ｓＴｏｗｎｓｈｉｐＦｏｒｅｓｔｒｙ￥ｂｙＸｕＧｕｏｚｈｅｎＰｏｖｅｒｔｙｉｓｓｔｉｌｌａｓｅｒｉｏｕｓｓｏｃｉａｌａｎｄｅｃｏｎｏｍｉ...

简介：Riceisthestaplefoodofmorethanhalfoftheworld'spopulation.Theproduction,processingandmanagementofpaddyricehaveprovidedthebasicconditionsforthelivingofmankind.Theproductionofricehasnotonlycreatedemploymentopportunitiesforonebillionagriculturalpopulationindevelopingnations,buthasalsocontributedtothedevelopmentofthesplendidcultureassociatedwithriceproduction.Hence,effectiveandproductivericesystemsplayaninfluentialroleindevelopmentofeconomyandimprovementofqualityoflife.Inviewofthis,on16December,2002,theUNGeneralAssemblydeclaredtheyearof2004theInternationalYearofRice.

简介：Forestshavemultiplebenefitsandfunctions,includingmitigationofclimatechange.Theimpactsofforestsontheglobalcarboncycleincludeforestsascarbonsinks,wood-basedproductsascarbonsinks,bio-energy,andproductionanduseofnon-timberproducts.Inthepastdecades,forestcoverofChinahasincreasedfrom8.6%to18.21%bylarge-scaleafforestationandconversionofcroplandintoforests.Forestbiomasscarbon(C)stockincreasedfrom4.3PgC(1PgC=1015gC)intheearly1980sto5...

简介：Asanemergingindustry,China'swoodfloorindustrydatesbacktotheearly1980s.Despitealatestart,ithasdevelopedrapidlyduringthelast20years.ThepastdecadeshavewitnessedgreatchangesinChina'swoodfloorindustry.Withhighquality,manyproducts"madeinChina"areavailablewidelyabroadnowadays.Currentglobaleconomicshocks,however,affectChina'sdomesticrealestatesector;hencethefallingdomesticsalesofwoodfloor.Thepaperaimstoidentifythecurrentsituationoffloorindustry...

简介：TheexcessiveexploitationandharvestingofforestresourcesduetoChina’seconomicconstructiondemandshavemadeitsforestresourcefallingintostructuralcrisis.Overthelastthreedecades,theareaofChina’snaturalforestsdecreasedby11millionha.Theareaofmaturedforestshasdecreasedfrom12millionhainearly50sto5.6millionhaatp

简介：Background:Withthelossofspeciesworldwideduetoanthropogenicfactors,especiallyinforestedecosystems,ithasbecomemoreurgentthanevertounderstandthebiodiversity-ecosystemfunctioningrelationship(BEFR).BEFRresearchinforestedecosystemsisverylimitedandthusstudiesthatincorporategreatergeographiccoverageandstructuralcomplexityareneeded.Methods:Wecompiledground-measureddatafromapprox.onehalfmilionforestinventorysampleplotsacrossthecontiguousUnitedStates,Alaska,andnortheasternChinatomaptreespeciesrichness,foreststocking,andproductivityatacontinentalscale.Basedonthesedata,weinvestigatedtherelationshipbetweenforestproductivityandtreespeciesdiversity,usingamultipleregressionanalysisandanon-parametricapproachtoaccountforspatialautocorrelation.Results:Ingeneral,forestsintheeasternUnitedStatesconsistedofmoretreespeciesthananyotherregionsinthecountry.ThehighestforeststockingvaluesovertheentirestudyareawereconcentratedinthewesternUnitedStatesandCentralAppalachia.Overall,96.4%ofsampleplots(477,281)showedasignificantpositiveeffectofspeciesrichnessonsiteproductivity,andonly3.6%(17,349)hadaninsignificantornegativeeffect.Conclusions:Thelargenumberofground-measuredplots,aswellasthemagnitudeofgeographicscale,renderedoverwhelmingevidenceinsupportofapositiveBEFR.Thisempiricalevidenceprovidesinsightstoforestmanagementandbiologicalconservationacrossdifferenttypesofforestedecosystems.Foresttimberproductivitymaybeimpairedbythelossofspeciesinforests,andbiologicalconservation,duetoitspotentialbenefitsonmaintainingspeciesrichnessandproductivity,canhaveprofoundimpactsonthefunctioningandservicesofforestedecosystems.

简介：Man-madeforest,whichistheforestecosystemofrehabilitationandreconstruction,playsasignificantroleintheprovisionofforestproductsandimprovementtheecologicalenvironment.Inthispaper,weestablishedtheAR(5)modeltopredictChina'sforestareafrom2009to2015.Thisstudyshowstheslowgrowthofthenationalplantationareatrendwithsomefluctuations,buttheoverallgrowthrateisnotlarge.WeproposedthatononehandChinashouldcontinuetoincreasetheplantationarea,ont...

简介：

简介：On16December2002,theUnitedNationsGeneralAssembly(UNGA)declaredtheyear2004theInternationalYearofRice(IYR).ThededicationofanInternationalYeartorice,asinglecrop,isunprecedentedinUNGA~shistory.IndeclaringtheIYR,theUNGArecognizedthatriceistheprimaryfoodsourceformorethanhalfoftheworld'spopulationandthatenhancing