The Comparative Study Of Ecological Function Of Indigenous Tree Species From Urban Forest Main In Chongqing

With the development of economy, the urbanization process of our country continues to accelerate. Meanwhile, the urban ecological problems are becoming serious, Urban forest plays an important role in resolving the ecological problems of city. Research has shown that the unicity problem of tree species is found in urban forest of our country, and proposed that indigenous tree species could be used to resolve the problem. At present, the selection of most tree species simply stays in the basic principle, and empirical level, and meanwhile, the landscape aesthetic function index get more and more attention. Therefore, the function of urban forest do not play well. For this reason, establishing an objective and scientific selection method of tree species has certain practical significance for tree species selection and enrichment of urban forest.Taking indigenous tree species as the research object in main urban areas of Chongqing, this paper analyzed the utilization status of indigenous tree species in Chonging. Using the hierarchical analysis (Analytic Hierarchy Process, AHP), the evaluation system of indigenous tree species was established in Chongqing urban, and high scores and unused indigenous tree species were screened. On the basis of the latitude zonality and vertical zonality principle, Zhao mu mountain botanical garden, Hong en temple forest park, Geese mountain park, Gele mountain national forest park, Huayan park, Southen mountain botanical garden, Chinese virtue park, holy light mountain forest park, Chongqing Jinyun mountain national nature reserve, and Beibei park were used as investigate plots, the AHP method constructing comprehensive evaluation system of indigenous tree species in the main urban areas of Chongqing was established. The results of the study were as follows:1. According to the survey results, the principal value of47kinds of indigenous tree species, were Cinnamomum camphora(L)Prcsl. Pinus massoniana Lamb., Ficus virens Aiton var. sublanceolata (Miq.)Corner, Ficus benjamina Linn., Robinia pseudoacacia Linn., Osmanthus henryi P.S.Green, Ginkgo biloba Linn., Cinnamomum japonicum Sieb., Magnolia grandiflora Linn., Quercus fabric Hance, Michelia alba DC. Syst., Broussonetia kazinoki S.et Z., Bischofia javanica Bl, Symplocos setchuanensis Brand, Machilus longipedicellata Lec., Pterocarya stenoptera C.DC., Ligustrum lucidum Ait., Liquidambar formosana Hance, Celtis sinensis Pers., Koelreuteria bipinnata Franch., Salix babylonica Linn., Magnolia soulangeana, Cedrus deodara (Roxb.)G.Don, Metasequoia glyptostroboides Hu et W.C.Cheng, Phoebe zhennan S.Lee et F.N.Wei, Elaeocarpus japoniens Sieb.et Zucc., Acer maximowiczii Pax, Jacaranda mimotifolia D.Don, Gordonia acuminata Chang, Firmiana platanifolia (Linn.f.)Marsili, Syzygium szechuanense Chang et Miau, Viburnum odoratissimum Ker-Gawl.var.awabuki (K.Koch)Zabel ex Rumpl., Symplocos laurina (Retz.)Wall., Symplocos laurina(Retz.)Wall, Cinnamomum septentrionale Hand.-Mazz., Rhus chinensis Mill., Schima crenata Korth., Ficus beipeiensis S.S.Chang, Bothrocaryum controversum (Hemsl.)Pojark.,Sapindus mukorossi Gzertn., Crateva formosensis (Jacobs)B.S.Sun grad.nov., Platycladus orientalis(L.)Franco, Lindera megaphylla Hemsl., Phoebe neurantha(Hemsl.)Gamble, Sapium sebiferum(L.)Roxb., Toxicodendron succedaneum(Linn.)O.Kuntze, Acer lucidum Metc., and Beilschmiedia yananica N. Chao in order.2. In this study,36kinds of indigenous tree species were selected for Chongqing urban area. They are Broussonetia kazinoki S.et Z., Robinia pseudoacacia Linn., Cedrus deodara(Roxb.)G. Don,Celtis sinensis Pers.,Cinnamomum camphora (L)Presl.,Ficus virens Aiton var.sublanceolata (Miq.) Corner, Symplocos setchuanensis Brand, Gordonia acuminate Chang, Pinus massoniana Lamb., Sapindus mukorossi Gzertn., Cinnamomum septentrionale Hand.-Mazz.,Koelreuteria bipinnata Franch., Magnolia grandiflora Linn., Ficus benjamina Linn., Osmanthus henryi P.S.Green, Ficus beipeiensis S.S.Chang, Ginkgo biloba Linn., Cinnamomum japonicum Sieb., Viburnum odoratissimum Ker-Gawl.var.awabuki(K.Koch)Zabel ex Rumpl., Crateva formosensis (Jacobs) B.S. Sun grad. nov., Elaeocarpus japonicus Sieb.et Zucc., Beilschmiedia yananica N. Chao, Ligustrum lucidum Ait., Pterocarya stenoptera C.DC., Magnolia soulangeana, Lindera megaphylla Hemsl., Michelia alba DC.Syst., Metasequoia glyptostroboides Hu et W.C. Cheng, Phoebe zhennan S. Lee et F. N. Wei, Bischofia javanica B1, Symplocos laurina (Retz.)Wall., Acer lucidum Metc., Quercus fabric Hance, Firmiana platanifolia (Linn.f.) Marsili, Salix babylonica Linn., and Jacaranda mimotifolia D.Don.3. Combination with field investigation, literature data and expert advice,14evaluation indexes were screened out. Using the AHP method, comprehensive evaluation system of advantage indigenous tree species was established for main urban areas of Chongqing. The results showed that:among the one-class indexes, the adaptability index weight was most important, whicht illustrated accounted for the most important position in selection of urban forest tree species; The second is ecology index, which should be considered in applying for urban forest tree species. Among the second-class indexes, drought resistance, barren resistance, solid carbon release oxygen, temperature and humidification, seasonal change and tree form were significantly greater than other indexes, They are important indicators for affecting the comprehensive evaluation system and selection tree species.