北京市論文：北京市行道樹結(jié)構(gòu)分析與健康評價

北京市論文：北京市行道樹結(jié)構(gòu)分析與健康評價【中文摘要】論文調(diào)查了北京市201段、378km各種類型道路的行道樹,根據(jù)北京市環(huán)路劃分不同區(qū)域、不同道路類型,進行了北京市行道樹健康實地調(diào)查、分析和評價。論文在分析北京市各區(qū)域、各種道路類型行道樹的樹種組成、生長指標結(jié)構(gòu)、病蟲害和管護等指標的基礎上,首次系統(tǒng)地從個體和群體兩個尺度對不同區(qū)域和不同類型道路的行道樹健康進行評價,并提出北京市行道樹健康經(jīng)營的建議措施。主要研究結(jié)論如下:1、北京市行道樹種類共計63種,其中喬木占24科31屬50種,灌木占8科12屬13種。按調(diào)查區(qū)域的分類統(tǒng)計來看,二環(huán)內(nèi)和二環(huán)至三環(huán)的區(qū)域內(nèi),喬木種類最為豐富,占喬木總種數(shù)的72.0%,其次為三環(huán)至四環(huán)、四環(huán)至五環(huán)、六環(huán)外的區(qū)域,分別占50.0%、52.0%和50.0%。各區(qū)域喬灌木比例差異明顯,且都以喬木樹種為主。多樣性指數(shù)和平均度指數(shù)的變化比較一致,從市區(qū)到郊區(qū)呈現(xiàn)出遞增的趨勢。2、整個市域的行道樹平均直徑為18.0cm。二環(huán)內(nèi)的平均直徑最大,為24.3cm,四環(huán)至五環(huán)區(qū)域最小,為11.4cm,徑階結(jié)構(gòu)較為合理。分區(qū)域來看,除了四環(huán)至五環(huán)區(qū)域外,胸徑呈現(xiàn)左偏正態(tài)分布的趨勢。分道路類型來看,快速路和次干路的結(jié)構(gòu)較為一致;而主干路和支路處于第二級徑階范圍的較多。種植數(shù)量最多的10種樹種平均胸徑大小依次為國槐>欒樹>銀杏>白蠟>圓柏>紫葉李>側(cè)柏>黃刺玫。3、行道樹樹高從不同區(qū)域的分布來看,各區(qū)域都在第二級出現(xiàn)峰值,即樹高在5-10m的數(shù)量最多,樹高大于15m的占總株數(shù)的5%。二環(huán)內(nèi)和二環(huán)至三環(huán)區(qū)域的變化幾乎吻合;三環(huán)至四環(huán)、五環(huán)至六環(huán)和六環(huán)外區(qū)域的分布趨勢基本一致;四環(huán)至五環(huán)區(qū)域的分布則表現(xiàn)為第一級和第二級樹高的數(shù)量相差不大,94%的樹木樹高小于10m。按道路類型的分布來看,主干路、次干路和支路的分布較為一致,以胸徑為5-10m的樹木為多,大于10m的樹木所占比例很小;快速路則以0-5m的小樹居多,為總株數(shù)的48%。4、北京市行道樹中落葉樹種與常綠樹種之比為14.5:1,全部行道樹中,常綠樹種只占總株數(shù)的6.5%。分區(qū)域的比較來看,二環(huán)內(nèi)和三環(huán)至四環(huán)區(qū)域的常綠樹最少,和落葉樹種的比例分別為1.7%和1.4%。二環(huán)至三環(huán)、五環(huán)至六環(huán)和六環(huán)外區(qū)域高于平均水平。不同道路類型的差異不大,常綠樹種比例均小于10%。5、北京市行道樹鄉(xiāng)土樹種和外來樹種之比為5.4:1,外來樹種種類比較豐富,但所占比例不大。不同區(qū)域的比較來看,五環(huán)至六環(huán)區(qū)域外來樹種的比例最大,占20.6%;二環(huán)內(nèi)區(qū)域外來樹種最少,占總株數(shù)的9.2%。二環(huán)內(nèi)和三環(huán)至四環(huán)區(qū)域的鄉(xiāng)土樹種比例超過全市平均水平。不同道路類型的比較來看,支路的鄉(xiāng)土樹種比例最低,為77.5%,次干路的比例最高,達89.0%。外來樹種在各個道路類型均有分布,快速路、主干路、次干路和支路分別為10、16、14、11種。6、通過截枝截干、樹基覆蓋、病蟲害、機械損傷等反映出北京市行道樹的管護情況。行道樹栽植時截枝截干的株數(shù)比例為15%,管護時截枝截干的行道樹木很多,高達70%;冠穴比(樹冠投影面積與樹穴面積比)為1:15.3;樹基有覆蓋的占半數(shù)以上,以綠地覆蓋的占35.19%,其它覆蓋類型共計不超過15%。適合用作樹基覆蓋的有機物僅占總數(shù)的1.78%;整體發(fā)生不同程度病害的比例為5.5%;大約有12%的行道樹受到不同程度的蟲害影響;樹皮不同程度損傷的比例為17.2%;有柵欄和樹池保護、刷白和經(jīng)常能有灌水措施的行道樹分別占總數(shù)的1%、20%與28%。7、全市隸屬于優(yōu)質(zhì)健康等級的行道樹占總株數(shù)4.8%;隸屬于健康等級的株數(shù)較多,為全部行道樹的24.99%;超過了半數(shù)的行道樹的健康情況處于亞健康狀態(tài),所占比例高達52.54%;不健康的比例為17.43%;0.24%的行道樹生長狀況惡化,處于瀕死狀態(tài)。從不同區(qū)域來看,瀕死和不健康等級的行道樹二環(huán)內(nèi)區(qū)域比例最大,五環(huán)至六環(huán)區(qū)域最小;健康狀態(tài)的行道樹以五環(huán)至六環(huán)區(qū)域的比例最大,二環(huán)至三環(huán)區(qū)域比重最小。快速路、主干路與次干路的行道樹健康情況呈近似右偏正態(tài)分布;支路則呈左偏正態(tài)分布,不健康等級的樹木比例較健康比例的樹木數(shù)量多。8、整體行道樹的健康評價得分為0.92,按照健康等級劃分為III級,即北京市行道樹整體處于亞健康狀態(tài),呈中等水平。整體健康指數(shù)由內(nèi)環(huán)至外環(huán)呈逐漸增大的趨勢。二環(huán)內(nèi)區(qū)域群體健康最差,健康指數(shù)為0.56,僅達到II級水平,處于不健康狀態(tài);二環(huán)至三環(huán)區(qū)域和三環(huán)至四環(huán)區(qū)域的行道樹群體健康指數(shù)分別為0.76和0.92,達到III級健康水平,呈亞健康狀態(tài);四環(huán)至五環(huán)、五環(huán)至六環(huán)和六環(huán)外區(qū)域的健康指數(shù)分別為1.04、1.14和1.06,整體達到了健康級別。不同類型道路行道樹健康情況差異較為明顯?？焖俾方】登闆r最差,健康指數(shù)為0.80,為亞健康狀態(tài),而其它類型道路的綜合健康指數(shù)分別為1.07、1.11與1.06,群體健康均達到IV級,處于相對良好的健康水平。針對北京市行道樹的現(xiàn)狀,本研究從樹種選擇、結(jié)構(gòu)調(diào)整、管護措施三個方面提出建議以改善行道樹的健康質(zhì)量?！居⑽恼?01sections,378kmvariousroadsroadsidetreesofBeijingwereinvestigatedinthisthesis.AccordingtoRingRoadsinBeijing,dividedalltheroadsintodifferentregions,differentroadtypes,andthendidthefieldinvestigation,analysisandevaluation.Analysisofeachregion,differenttypesofroadsidetreesinthespeciescompositionoftheroad,growthindexstructure,pestmanagementandprotectiononthebasisofotherindicatorsinbeijing,thisthesissystematicallyforthefirsttimeevaluatethetwoscalesfromindividualsandgroupsindifferentregionsanddifferenttyperoadsofroadsidetrees,andmakerecommendationsabouttheheathmanagementofroadsidetreesinBeijing.Themainconclusionsareasfollows:1.Thereare63roadsidetreespeciesinBeijingwhichthearbortreestakeup24families,31generas,50kinds,theshrubstakeup8families,12generas,13kinds.TheformedtreeismostabundantinTheareainside2ndRingRoadandTheareabetween2ndand3rdRingRoad,itistakeup72persentageofthetotaloftheformedtree,thenTheareabetween3rdand4thRingRoadandTheareaoutside6thRingRoadaretakeup50%,Theareabetween4thand5thRingRoadis52%,therentofthetreeshrubshaveacleardiffirencesthatitisprioritytotheformedtrees.thechangeoftheDiversityindexandaverageindexisconsisitent,fromthecitytothesuburbshaveanincreasedtrends.2.TheaverageDBHofroadsidetreesthroughouttheCityis18.0cm.Theareainside2ndRingRoadhasthelargestaverageDBHthatis24.3cm,Theareabetween4thand5thRingRoadlocalminimumforthe11.4cm,DBHclasssstructureismorereasonable.Sub-region,inadditiontoregionalVictoriatotherings,thediameterofleftsideshowthetrendofnormaldistribution.Sub-typeofroadrun,expresswaysandSecondaryroadsofthestructureisconsistentwiththenumberofpathsformulti-leveltrees;andtrunkroadsandbranchdiameterclassesinthescopeofthesecondstagemoreofthesmalldiameterandlargediameterRelativelyfewtrees.Plantingthelargestnumberofaveragediametersizeof10specieswereSophorajaponica>Koelreuteriapaniculata>Ginkgobiloba>Fraxinuschinensis>Sabinachinensis>Prunuscerasifera>Chinesearborvitae>Rosaxanthina.3.Thedistributionoftheroadsidetreesaheight,theregionallevelinthesecondpeak,thatis,height5-10minthelargestnumberoftreestallerthan15mbutnotmany,only5%ofthetotalnumberoftrees.Theareainside2ndRingRoadandtheareabetween2ndand3rdRingRoad’schangeisalmostconsistent;theareabetween3rdand4thRingRoad,theareabetween5thand6thRingRoadandtheareaoutside6thRingRoadconsistentwiththedistributionoftrends;tetracyclictopentacyclicregionaldistributionoftheperformanceofthefirstAndsecond-levelnumberoftreeheightorless,94%ofthetrees,treeheightislessthan10m.Accordingtothedistributionofroadtype,Mainroads,Secondaryroadsandbranchroads’distributionismoreconsistentforthe5-10mindiameteratbreastheightoftreeswasmorethanasmallproportionoftrees10m;Expresswayhas0-5mofthetreesaremostly48%ofthetotalnumberoftrees.4.AmongtheRoadsidetreesinBeijingCity,theratioofdeciduoustreesandevergreentreesis14.5:1.Evergreentreesisonly6.5%ofthetotalnumberoftrees.Comparingthedifferentregions,theevergreentreesintheareainside2ndRingRoadandtheareabetween3rdand4thRingRoadaretheleast.Inthesetwoareas,theratioofevergreentreesanddeciduoustreesis1.7%and1.4%.Thenumberofevergreentreesintheareabetween2ndand3rdRingRoad,theareabetween5thand6thRingRoadandtheareaoutside6thRingRoadisabovetheaverage.Thereislittledifferencebetweendifferenttyperoads,theratioofevergreentreesislessthan10%.5.TheratioofnativetreesandexotictreespeciesamongtheroadsidetreesinBeijingis5.4:1.Asyoucansee,therichfulexotictreespeciesonlytakesupasmallproportion.Basedondifferentareas,exotictreespeciestakesupthelargestproportionbetween5thand6thRingRoadwhichis20.6%,whilethemtakesupthesmallestproportioninside2ndRingRoadwhichis9.2%.Theamountofnativetreesinside4thRingRoadisovertheaverageamountinbeijing.Basedondifferentroadtypes,nativetreestakesupthesmallestroomwhichis77.5%onbranchroads,secondaryroadsthelargestwhichis89%.Exotictreespeciescoversallkindsofroadtypes,Expresswayswith10species,Mainroadswith16species,Secondaryroadswith13species,whilebranchroadswith11species.6.Theprunemanagement,Tree-basedcoverage,diseasesandinsectpests,mechanicaldemagereflectsthecasemanagementandprotectionofBeijingroadsidetrees.Theprunemanagementwhenplantingtakesup15%,whiletheprunemanagementofmanagementandprotectiontakesupalargeamountwhichis70%.Theaverageareaofroadsidetreesis1.53m2,whiletheprojectiveareaofcrownis23.5m2,whichmakestherationbetweenthemis1:15.3.Amongtheroadsidetrees,tree-basedtakesupmorethanahalf,whilethegreencoveredonestakeup35.19%,therestofthemarecoveredbyothertypesofprotectionswhichtakesup5%.Theorganiccompoundswhicharesuitablefortree-basedcoverageonlytakesup1.78%.Theroadsidetreessufferedfromvariousdiseasetakeup5.5%,about12%ofthemareaffectedbyinsectpest,theinjuredbarktakesup17.2%.theroadsidetreeswhichareproctecedbyfence,treepond,whitenandirrigationmeasurestakesup1%,20%and28%.7.HalfofthemblongtoSub-healthstatewhichmakeup52.24%,thetopqualityroadsidetreestakeup4.8%,whilethehealthyonestakeup24.99%.theunhealthyonestakeup17.43%.0.24%ofthemaredying.Accordingtodifferentregions,thedyingroadsidetreesandunhealthyonesinside2ndRingRoadtakeupthelargestproportion,andtherearefewofthembeteen5thand6thRingRoad.Sub-healthyroadsidetreestakeupalargeproportionalloverthearea.Thehealthyonestakeupthelargestproportionoutside4thRingRoad,whiletheytakeupthelargestroombetween5thand6thRingRoad.Thefarthertheylivefromthedowntown,thebettertheirstateis.Italsoimpliesthetop-qualityroadsidetreesexistlessinside2ndRingRoadarea.ThestateoftheroadsidetreesshowanapproximatenormaldistributionskewedtotherightamongExpressways,MainroadsandtheSecondaryroads,onthebrachroadstheyshowaleftbiasnormaldistribution.Allinall,theamountofunhealthyleveltreesareoverthehealthyones.8.TheoverallHealthEvaluationscoreis0.92ofroadsidetrees,whichmakesthembelongtolevelIIIaccordingtohealthscore.ItalsosuggeststhattheroadsidetreesinBeijingbelongtoSub-healthstate,aswellasmediumlevel.Theoverallhealthindexshowsanextendtrendfromtheinnerareatotheouterringarea.Theunhealthyroadsidetreeswithin2ndringroadofwhichthehealthystateis0.56belongtolevelII.Andthesub-healthyroadsidetreeswithin2ndand4thringroadofwhichtheindexis0.76overthe2ndringroadand3rdringroad,0.96overtheoverthe3rdringroadand4thringroadarea,whichmakesthembelongtolevelIII.Theindexis1.04overthe4thringroadand5thringroadarea,and1.14overthe5thringroadand6thringroadarea,1.06outsidethe6thringroad,whickmakesthemallbelongtohealthystate.Basedondifferentroadtyes,thedifferencesarequiteobvious.Expresswayroadsidetreesofwhichtheindexis0.8belongtoSub-healthystate.Theoverallstateoftherestroadsidetreesisrelativelyhealthy,theirindexare1.07.1.11and1.06whichmakethemallbelongtolevelIV.Thisstudyputsforwardtreespeciesselection,restructuring,managementandprotectionmeasuresthreerecommendations,inordertoimprovingthehealthqualityofroadsidetreesinBeijing.【關鍵詞】北京市行道樹樹種結(jié)構(gòu)健康評價個體健康群體健康【英文關鍵詞】BeijingRoadsidetreeTreestructureHealthassessmentIndividualHealthPopulationHealth【目錄】北京市行道樹結(jié)構(gòu)分析與健康評價

摘要

5-8

ABSTRACT

8-11

第一章緒論

18-27

1.1引言

18-26

1.1.1研究背景

18-19

1.1.2國內(nèi)外研究現(xiàn)狀及評述

19-26

1.2研究內(nèi)容及意義

26-27

1.2.1主要研究內(nèi)容

26

1.2.2研究意義

26-27

第二章研究區(qū)概況與研究方法

27-37

2.1研究區(qū)概況

27-28

2.1.1地理位置

27

2.1.2氣候特點

27

2.1.3行政區(qū)劃

27-28

2.1.4道路概況

28

2.1.5物種概況

28

2.2研究方法

28-37

2.2.1調(diào)查樣地的選擇與劃分

28-29

2.2.2調(diào)查方法

29-31

2.2.3行道樹結(jié)構(gòu)分析方法

31-32

2.2.4行道樹健康評價方法

32-37

第三章北京市行道樹結(jié)構(gòu)特征分析

37-60

3.1行道樹結(jié)構(gòu)組成分析

37-