简介:在P下面在P缺乏的allophanic土壤在磷(P)部分变化。在壶用扫帚(CytisusscopariusL.)和毒麦(Loliummultiflorum)种的radiata幼苗被学习在以在根围决定导出施肥料的P的命运的·g−1,玷污的0,50,和100μg的率的三倍的过磷酸钙的申请以后的14个月。Pfertiliser的申请增加了NaOH-Pi,NaOH-Po,和H2那么4-P在土壤的i集中,但是减少residual-P集中。resin-Pi集中,在这土壤极其低,1~3μg·g−1),仍然是一样。增加的fertiliserP的多数然而在NaOH-Pi部分(40%49%)。这由于在这土壤(92%)的高P固定。第二最高的P恢复在NaOH-Po部分(7%19%)。在以0μg·g−1,的率的P缺乏的状况或增加下面NaOH-P在radiata根围土壤的i集中在体积土壤和草根围土壤是比那低的。这可能在释放了一些在根围修理到土壤的P的P缺乏的条件下面由于由根和mycorrhiza的更高的盐生产,它需要在未来研究被测试。
简介:我们比较了在处于Karnataka的状态种区域的三棵宽广柚木从三个种子生产区域(矿泉)和柚木(TectonagrandisL.f)的三个相应未耕过的看台(UIS)获得的子孙的词法、基因的属性,印度。一般来说,播种象种子重量,种子尺寸和种子空虚那样的词法参数在与UIS相比的矿泉是显著地优异的。种子萌芽百分比在从矿泉的种子也是更高的。在二每月的间隔测量六个月的幼苗性能被观察在在比较的三个区域中的二个的矿泉优异。尽管矿泉的子孙的基因差异根本比UIS低区域,价值中等高。当差异索引否定地每种子与水果重量,水果直径和核重量被相关时,萌芽百分比断然每种子与水果重量和核重量被相关。矿泉没有对未来种植园的基因差异的严重威胁作为中等改进的种的材料的来源证明重要。
简介:Settingmonitoringtransectinthemiddleandshallowwaterarea(altitude156-172m)inThreeGorgesreservoirhydro-fluctuationbelttoresearchthechangingcharacteristicsofthecontentsofN,P,K,pHandorganicmatterofthesoilwhichexperiencedtheinfluenceoffluctuationthefirsttime.Theresultsshowedthatbytheinfluenceofwaterlevelfluctuating,contentsofsoilN,P,K,pHandorganicmatterhadreducedindifferentsoillayersinhydro-fluctuationbelt.TheavailableNdecreasedby41.53%-59.87%,availablePdecreasedby5.26%-36.76%,availableKdecreasedby3.55%-45.56%,totalNdecreasedby9.52%-40.00%,totalPhadnochangegenerally,totalKhaddecreasedalittle,contentoforganicmaterialdecreasedby7.62%-37.83%%,pHvalueturnedtoneutral,changedby1.73%-9.58%.
简介:Background:Theglobalsearchfornewwaystosequestercarbonhasalreadyreachedagriculturallands.Suchlandconstitutesamajorpotentialcarbonsink.Theproductionofhighvaluetimberwithinagroforestrysystemscanfacilitateanin-situcarbonstoragefunction.Thisisfollowedbyapotentiallongtermex-situcarbonsinkwithinlonglastingproductssuchasveneerandfurniture.Forthispurposewildcherry(PrunusaviumL.)isaninterestingoptionformiddleEurope,yieldinghighpricesonthetimbermarket.Methods:Atotalnumberof39wildcherryweresampledin2012and2013toassesstheleaflessabovegroundbiomass.Thecompletetreesincludingstemandbrancheswereseparatedinto1cmdiameterclasses.Woodandbarkfromsub-sampleswereanalysedseparatelyandnutrientcontentwasderived.Modelsforbiomassestimationwereconstructedforalltreecompartments.Results:Thesmallestdiameterclassespossessthehighestproportionofbarkduetosmallercrosssectionalarea.Treeboleswithagreateramountofstemwoodabove10cmindiameterwillhaveamoreconstantbarkproportion.Totalbranchbarkproportionalsoremainsrelativelyconstantaboved_(1.3m)measurementsof8cm.Abalanceisevidentbetweentheproductionofnewbrancheswithalowdiameterandhighbarkproportionoffsetbythethickeningandarelativereductioninbarkproportioninlargerbranches.Theresultsshowthatasingletreewithanageof17and18yearscanstoreupto85kgofcarbonwithintheabovegroundbiomassportion,anamountthatwillincreaseasthetreematures.Branchesdisplaygreaternutrientcontentthanstemsectionspervolumeunitwhichcanbeattributedtoagreaterbarkproportion.Conclusions:Usingthederivedmodelsthecarbonandthenutrientcontentofabove-groundwoodybiomassofwholetreescanbecalculated.Suggestedvaluesforcarbonwithothermajorandminornutrientsheldwithinrelativelyimmaturetreesstronglysupportstheideaoftheinclusionofwildcherrywithinagroforestrysystemsasan
简介:Background:Themainobjectiveofthisstudywastoexaminetheclimaticsensitivityoftheradialgrowthresponseof13easternwhitepine(PinusstrobusL.)provenancesplantedatseventestsitesthroughoutthenorthernpartofthespecies’nativedistributionineasternNorthAmerica.Methods:Thetestsites(i.e.,Wabeno,Wisconsin,USA;Manistique,Michigan,USA;PineRiver,Michigan,USA;Newaygo,Michigan,USA;TurkeyPoint,Ontario,Canada;Ganaraska,Ontario,Canada;andOrono,Maine,USA)examinedinthisstudywerepartofarange-widewhitepineprovenancetrialestablishedintheearly1960sintheeasternUnitedStatesandCanada.Principalcomponentsanalysis(PCA)wasusedtoexaminethemainmodesofvariation[first(PC1)andsecond(PC2)principalcomponentaxes]inthestandardizedradialgrowthindicesoftheprovenancesateachtestsite.TheyearscoresforPC1andPC2wereexaminedinrelationtoanarrayoftestsiteclimatevariablesusingmultipleregressionanalysistoexaminethecommonalityofgrowthresponseacrossallprovenancestotheclimateofeachtestsite.ProvenanceloadingsonPC1andPC2werecorrelatedwithgeographicparameters(i.e.,latitude,longitude,elevation)andasuiteofbiophysicalparametersassociatedwithprovenanceoriginlocation.Results:TheamountofvariationinradialgrowthexplainedbyPC1andPC2rangedfrom43.4%to89.6%.Dendroclimaticmodelsrevealedthatwhitepineradialgrowthresponsestoclimatewerecomplexanddifferedamongsites.Thekeydendroclimaticrelationshipsobservedincludedsensitivitytohightemperatureinwinterandsummer,coldtemperatureinthespringandfal(i.e.,beginningandendofthegrowingseason),summermoisturestress,potentialsensitivitytostorminduceddamageinspringandfal,andbothpositiveandnegativeeffectsofhigherwintersnowfal.Separationoftheloadingsofprovenancesonprincipalcomponentaxeswasmainlyassociatedwithtemperature-relatedbioclimaticparametersofprovenanceoriginat5ofth
简介:Apotexperimentwasconductedtoinvestigatetheeffectsofnitrogencontent[N1(nofertilizer),N2(0.15g?kg–1),andN3(0.3g?kg–1)]onthegrowthandthehydrauliccharacteristicsofpeachseedlingsunderdifferentsoilmoistureconditions(W1,W2andW3,inwhichthesoilwatercontentwas45%to55%,60%to70%,and75%to80%ofthefieldwatercapacity,respectively)byusingaspecializedhighpressureflowmeterwitharootchamberandacoupling,whichwasconnectedtoplantorgans.Leafareaandleafhydraulicconductivity(KL)increasedsignificantlyintheseedlingsbecauseofincreasedsoilmoistureandNcontent.KLincreasedwithleafarea.AlinearcorrelationwasdocumentedbetweenKLandleafarea.KLwashigherinthemorningandbegantodeclinesharplyafter16:00,atwhichKLdeclinedafteraninitialincrease.SoilmoistureandNcontentenhancedshoot(Ks)androot(Kr)hydraulicconductivities,therebyimprovingthelowsoilmoistureconditiontoalargeextent.KsandKroftheseedlingswerereducedby32%and27%respectivelyinN1,andby14.7%and9.4%,respectivelyinN2,andbothinW1,comparedwiththecontroltreatment.N3hadnosignificanteffectonKsandKrundersimilarconditions.LinearnegativecorrelationswereobservedbetweenKrandtheexcisedrootdiameteraswellasbetweenKsandtheshootstemdiameter.Theshoot-to-rootratioincreasedwithincreaseinNcontent.Theshoot-to-rootratioinN3wasincreasedby14.37%,comparedwithN1inW1aswellasby12%and4.39%inW2andW3,respectively.KnowledgeoftheeffectsofsoilmoistureandNfertilizeronhydrauliccharacteristicsandgrowthisimportant.Ourresultsprovidebasicguidelinesfortheimplementationofwater-savingirrigationandfertilizationmanagementofnurserystock.
简介:根据扬州环境优势和生态城市建设需求,以林网化-水网化相结合的中国城市森林规划理念为指导,进行了以扬州市区为核心、面向市域的开放统一的林业发展规划.在市域,围绕沿运河和沿江的城市发展,突出区域协调、生态一体的考虑,提出了"两带、两片、三网"的林业建设框架;在市区,以古运河为文脉,突出"水乡生态"与"历史文化名城"的主线,提出"一环、四楔、两廊、多核"的城市森林建设布局.从而在扬州地区形成体现"绿色屏障、绿色产业、绿色文化"三位一体、功能健全的现代林业发展格局,在市区达到"绿带环绕、四楔穿插、两廊相连、多核点缀"的城市森林建设效果,为扬州经济社会的可持续发展和建设和谐社会奠定生态基础.
简介:城市的高度集聚使城市发展的负效应与非经济性急剧增长,如常见的"热岛效应"、"雨岛效应"、"干岛效应"、"闷岛效应"、"浑浊岛效应"等.如何走可持续发展之路,全面实现我国小康社会目标,改善城镇生态环境已成为当务之急,也应该是我国生态环境建设重点[1].针对中国的国情,我们提出了中国森林生态网络体系建设的构想,从整个国土生态安全的视野,即点、线、面结合,构成我国陆地森林生态网络体系,达到全面遏制生态恶化的趋势[2].其中,中国森林生态网络体系"点"的建设主要是指人口密集的城镇森林建设.该项目经过了将近10年的实践,取得了一些阶段性成果,其中有关城市森林建设的思想已成为中国可持续发展林业战略的重要内容,这些都为我国在21世纪的城市森林建设打下了良好的基础.