Study On The Plant Arrangement And Environmental Effect Of The Ecological Urban Forest Along Grand Canal In Yang Zhou

The thesis takes the ecological urban forest along grand canal in Yang Zhou as study object, the plant arrangement of the greenbelt system and the ecological functions of some of the trees were studied. The species of the trees were studied systematically in March and Aprial,2005. The ecological benefits, such as carbon fixation and oxygen relase, transpired water volume and absorbed caloric of leaf were studied from June to August, 2006. In order to study and analyze from different aspects, on one hand this article studied from the principal part of the ecological effect—the plants; on the other hand, the environment was analyzed as the object which was taken effect by the trees. All this work was useful to the planting designing.The main conclusion and suggestion as follows:There are about 88 species plants in the ecological urban forest along grand canal in Yang Zhou, belongs to 67 genuses, 43 families. It indicates that the ratio of local species and alien species, evergreen species and deciduous species, arbor species and shrub species are 1.44:1, 1:1.6, 1.5:1. In the main, the structure is reasonable, except that the deciduous species should be increased. The quantity of the flower species is 46, whose month of bloom is mainly from March to July. There are about 26 species which people appreciate them for the leaves, about 21 species for the fruits, and about 12 species for the shape. Flowers and beautiful scenery are around all the seasons. The model case which arranged the plants by one Prunus persica., one Salix babylonica indicates the local distinguishing feature, and goes through with the principle that ecology first and landscape second.Based on the vegetative cover, there are two kinds of evergreen arbor species (Maguolia grandiflora and Cinnamomum camphora), and two kinds of deciduous arbor species (Salix babylonica and Ginkgo biloba) are the excellent upper levels species to make green by planting trees; the Prunus cerasifera, Nerium indicum and Chimonanthus praecox are the good middle levels species; the Ligustrum quihoui is the the great lower levels species.According to the amount of Carbon fixation and Oxygen release for each species plant of every square meter land a day, the Robinia pseudoacacia. and Salix babylonica are the excellent upper levels species to balance the air Carbon and Oxygen, and the next species are Maguolia grandiflora, Sophora japonica and Eriobotrya japonica; the Nerium indicum and Prunus persica. are the great middle levels species; the Ligustrum quihoui is the great lower levels species. In the 19 species of greening plants, the different type of plants have the different amount of Carbon fixation and Oxygen release, which shows that: the evergreen shrub species are better than deciduous arbor species which are better than evergreen arbor species, and the deciduous shrub species are the lowest. The model case which arranged the plants by one Prunus persica.,one Salix babylonica can fix Carbon for about 53.37gm-2d-1 and release Oxygen for about 38.81gm-2d-1 . It is a great model case.In the light of the amount of transpired water volume and absorbed caloric of leaf for each species plant of every square meter land a day, the Robinia pseudoacacia. is the excellent upper levels species to better the microclimate, and the next species are Cinnamomum camphora, Maguolia grandiflora, Salix babylonica and so on; the Prunus persica. is the great middle levels species and the average amount of transpired water volume of the Prunus cerasifera,Chimonanthus praecox and Nerium indicum is about 5kg·m-2·d-1; the Ligustrum quihoui is the great lower levels species. In the 19 species of greening plants, the different type of plants have the different amount of transpired water volume and absorbed caloric of leaf, which shows that: deciduous arbor species are better than evergreen shrub species which are better than evergreen arbor species and the deciduous shrub species are the lowest. The model case which arranged the plants by one Prunus persica.,one Salix babylonica can decrease for about 1.3℃every square meters and transpire water volume for about 8kg·m-2·d-1 .The study on the different plantation structures (arbor-shrub-herb type, arbor-shrub type, arbor-herb type, arbor forest type, shrub-herb type and herb type) shows that: the shading effect of the greenbelt is determined by the species and the growing conditions of the plants, and the arrangement of the trees should be considered. The model which is arranged by the strong transpiration trees with plenty green quantity has the better effect of decreasing temperature and increasing air humidity than the other models; with the same plants, the complex models are better than the simplex models. The greenbelt effect of adjusting CO2 concentration is closely bound up with the type of plants, which depends on not only the trees photosynthesis, but also the green quantity.