【作者】 张前进；

【导师】 吴泽民；

【作者基本信息】 安徽农业大学 ， 森林培育， 2014， 博士

【摘要】 城市景观生态林是构成城市环境的重要组成部分,其对城市环境的改善有着不可替代的作用。随着人们对城市环境质量需求的不断提高,城市景观生态林建设越来越得到重视,以什么思路建设的城市景观生态林,不仅造价低,美学价值高,而且生态环境效益也高是有待解决的问题。本文以合肥城市景观生态林作为研究对象,采用样地调查分析的方法总结出合肥城市景观生态林类型主要有22个类型。为了让22种林地类型具有可比性,把树木规格统一为合肥绿化大会战对树木规格进行建设成本计算,得出成本最高的前五种组合,按高低排序为:雪松+蚊母树组合、银杏+蜀桧+栾树—红花继木组合、重阳木+广玉兰+白榆组合、垂柳+香樟—紫叶李组合和香樟+无患子—桂花组合。成本最低的五种组合,按低到高排序为:黑松+香樟+蜀桧—金钟花组合、湿地松组合、香樟—石楠组合、池杉+雪松+重阳木+乌桕组合和重阳木+马褂木组合。对22种城市景观生态林采用SBE法进行美学评价,结果表明:合肥城市景观生态林整体美景质量不高,城市景观生态林美景度与阔叶树比例、平均胸径、平均冠幅、有色树木比例、草坪盖度5个景观要素呈线性相关,影响城市景观生态林美景度高低顺序为:阔叶树比例>平均胸径>平均冠幅>有色树比例>草坪盖度。通过测定光合速率和蒸腾速率,研究12个主要树种春季的耗水性。高水分利用的植物有栾树,三角枫、紫叶李、女贞、香樟、桂花,特别是栾树表现出低蒸腾高水分利用的特点,低水分利用的植物有乌桕、垂柳、广玉兰、银杏、重阳木、悬铃木,其中银杏、重阳木、悬铃木表现高蒸腾低水分利用的特点。树木春季耗水特点可作为选择节水型树种的依据,乡土树种栾树和三角枫可作为节水型树种推广。借鉴国外的计算方法并加以改进提出城市树木价值计算公式为:城市树木的价值=胸高(1.3米)树干断面积×树木基价×树种系数×生长位置系数×生长情况系数×观赏特性系数×生态效益系数。通过比较胸径8cm全冠香樟和胸径25cm截干香樟,栽植后25年的生长,结果表明:胸径25cm截干香樟在栽植后胸径增长速度慢于胸径8cm全冠香樟。总体上看,胸径8cm香樟的冠幅一直大于25cm截干香樟的冠幅,胸径8cm全冠香樟叶面积的增长幅度大于胸径25cm截干香樟,使用大树截干作为城市绿化的材料性价比也远远小于使用小规格全冠树木。广玉兰枝条中重金属含量与土壤重金属含量之间没有明显的相关性,对于同一绿地类型中土壤和广玉兰枝条中五种重金属含量也各不相同,每种重金属的分布情况都不同。对1 10年龄的广玉兰年轮生长量与城市气候的关系分析,结果表明:年轮生长量与年平均温度的关系呈负相关,但与年降水量、年日照时数和年平均相对湿度呈正相关。基于以上方面分析评价,提出模仿当地自然植物群落或近自然植物群落的思路进行资源节约型城市景观生态林构建思路,同时提出合肥城市景观生态林修复思路。更多还原

【Abstract】 City landscape ecological forest(CLEF)is an important part of city environment,and plays an irreplaceable role in improving city ecological environment.Along with the people demand unceasing enhancement to the city environmental quality,the city landscape ecological forest construction is getting more and more attention.Then what does the idea to construct the city landscape ecological forest,not only has the advantages of low cost and high aesthetic value,but ecological and environmental benefit is high.That is a problem to be solved now.According to species composition all investigated stands were classified to be as formation,and a vegetation classification was built as well,in Hefei city.Based on field survey,22 formatons in cluding commosition species were identified.In order to make the types 22 of CLEF comparable,the unified specification base on the gude for tree planting published by park administration office was employed to make calculation for construction cost.The top five types rated in expenditure of building in order are Cedrus+Distylium racemosum combination、Ginkgo biloba+Sabina komarovii+Koelreuteria integrifoliola-Loropetalum chinense combination、Bischofia polycarpa+Magnolia grandiflora+Ulmus pumila combination、Salix babylonica+Cinnamomum camphora-Prunus ceraifera combination and Cinnamomum camphora+Sapindus mukurossi-Osmanthus fragrans combination.The lower expenditure for communit building are Pinus thunbergii+Cinnamomum camphora+Sabina komarovii-Forsythia suspense combination,pinus elliottii combination,Cinnamomum camphora-Photinia serrulata combination,Taxodiumascendens+Cedrus+Bischofia polycarpa+Sapium sebiferum combination and Bischofia polycarpa+Liriodendron chinensis combination.Aesthetic evaluation to 22 formations of CLEF by using SBE method,results show that the overall scenic beauty quality of landscape ecological forest is not high in Hefei City.The scenic beauty for CLEF has great relevance to 5 landscape elements,that are broadleaf tree ratio,average DBH,average crown width,color trees proportion and Lawn coverage ratio.The effecting degree of these elements is lisited in order:the proportion of broad-leaved tree>average DBH>average crown>the proportion of color tree>Lawn coverage ratio.Based on field measure of net photosynthesis rate and transpiration rate,the water use efficiencies(WUE)for 12 major tree species of CLEF was calculated in spring.The water consumption is different for different species in spring.Koelreuteria integrifoliola is rated at the highes,then Acer buergerianum,Prunus cerasifera,Ligustrum lucidum,Cinnamomum camphora,Osmanthus fragrans werel also listed at higher water consumption level in order,meanwhile Koelreuteria integrifoliola showed low transpiration and high water use characteristics.Tree species for low water comsumption are Sapium sebiferum,Salix babylonica,Magnolia grandiflora,Ginkgo biloba,Bischofia polycarpa,Platanus acerifolia.The 3 of them,Ginkgo biloba,Bischofia polycarpa,Platanus acerifolia showed higher transpiration and lower water use characteristics.The characteristic of water consumption in spring for tree species could be employed as a basical guid for selection of water-saving tree species,the native species,Koelreuteria integrifoliola Sapium sebiferum and Acer buergerianum could be used as water-saving specis to build CLEF;But if consideration water saving,the species such as Ginkgo biloba,Bischofia polycarpa,Platanus acerifolia should not be selected.Referencing the calculation methods used in European and America author designed an improved in this paper formula:City tree value=Trunk basal area(at breast high 1.3 meters)× tree base price × Tree species coefficient × tree growth position coefficient x growth situation coefficient × ornamental characteristic coefficient × ecological benefit coefficient.Cinnamomum camphora trees were transplanted using different plant methods,one is big tree at dbh 25cm and cut back whole crown(described as cutback tree as following),another is small at dbh 8cm but with whole crown(described as whole crwon tree as following),then the growth comparison between them are analyzed dynamically for 25 years after transplanting.The results show that cut back tree stem diameter growth after planting slower than whole crown tree.On the whole,The whole crwon tree is greater than cutback tree always.Comparison Leaf area increasing between two trees,that of wole craow and cutback treeo,the leaf area of the former is always larger than that of the later one.Aothour make conclution that transplating small trees with whole crown is much beter than that of big tree with no crown at all for both economic and aethstic views.There is no obvious correlation about heavy metals content between soil content and branch of Magnolia grandiflora Two heavy metals content of Magnolia grandiflora branch collected from the same types of greenbelts but different locations are not identical,and the distribution of heavy metals are different.The analysis of annualring increasing for 110 years indicated that the relationship between annualring growth and annual average temperature showed a negatively relevant,but has a positively relevant with annual precipitation、annual sunshine hours and the average relative humidity of year.Based on the analysis and evaluation of the above put forward to imitate the natural plant community or nearly natural plant community to constructe resource-saving city landscape ecological forest.And put forward to landscape ecological forest restoration ideas in Hefei city.更多还原