Studies On The Composition Feature Of Gardening Plant Communities In Main Urban Areas Of Qiqihar City

The plant community is the basic unit of urban green space， and its structuralcharacteristics determine the effect of plant landscape and ecological functions. It will play avery important role if we build a scientific and rational， sound and mature plantcommunities， in air purification， climate regulation， and enhance the effect of greenlandscape， protect and beautify the environment， maintain urban ecological balance. In thispaper， garden plant communities of the main urban areas of Qiqihar city as the main object，investigations green space is divided into three types， including the Colleges andUniversities campus green， the main city of green parks， and the residential areas andstreets green， according to the present situation and characteristics of the existing greenspace. Set up a typical sample plots according to the regional plant size and position， surveytree layer and the shrub layer main species and analyze statistic survey data. Investigationshowed that in the typical sample plots there are trees and shrubs chiefly15families and28species in three universities， there are trees and shrubs chiefly15families and45species inthe two parks， there are trees and shrubs chiefly15families and32species inneighborhoods and the streets. Different types of species diversity in the city:Green of parks>Green of residential areas and streets> Green of Colleges and Universities campus. InColleges and universities， parks， residential areas and streets， trees DBH range mainlyconcentrated in5-30㎝diameter level，accounting for about80%of the total trees surveyed.Qiqihar Forestry School， LongSha Park， The tree distribution is more in the east part andcentral part of Qiqihar University， especially a larger proportion of more than10m trees. InQiqihar University， The important value of Uimus pumila has an absolute advantage， Theimportant value of Sabina procumbens and Populus simonii is low， the important value formost species is about50， The distribution is relatively balanced. In Qiqihar forestry school，Cornus stolonifera are quite important， The important value of Weigela praecox is thelowest， the important value for most species is between30-80， The distribution is relativelybalanced. In Qiqihar Vocational Education Center.The important value of Syringamandshurica is the lowest. The important value of Salix matsudana and Uimus pumila ishigher. The important value for most species between40-80， the distribution is more balanced. Through the analysis of the composition， distribution and structural characteristicsof the plant community trees， shrubs in Qiqihar city， Combined with Qiqihar regiongeography position， existing plant resources， cultural characteristics and developingdirection， protecting biological diversity， dispatching plant resources appropriately，exploring the ecological basis of Qiqihar urban green space planning and construction work.