Study On The Ecological Effect Of Main Greenland In Main Urban Area Of Chongqing

Urban greenland system is an important part of urban ecological system, and the ecological benefit of greenland affects the quality of environment of whole city. There have been a few researches on the ecological benefit of greenbelt ecological system, in and out of nation. The researches about ecological benefit of greenbelt began earlier abroad, more quantitative, and more systemic. But, it is another situation in China.This thesis takes the greenland system in Chongqing main urban area as study object, and studied the relationships between types of Greenland and ecological benefit, between communities structure of Greenland and ecological benefit, and between the tree species in greenland and ecological benefit. The mian greenland types in main urban area of Chongqing were studied systematically from July to September in 2004, from December in 2004 to January in 2005, and from July to September in 2005, and the effect of main species plant leaves in greenland on dust removal and on sulfur absorption was studied during this period. The ecological factors were also studied that is the effect of different types green area and plant community on sulfur content in atmosphere reduction, light intensity reduction, temperature bring down, humidity increment and cpacity. The result shows:1. The quantity of dust removal of plant leaves in different types of green area is different, and that of plant leaves in street greenbelt is larger than that in parks. The quantity of dust removal is different between plant growth types, either in street greenland or in parks, and that of shrub is larger that of tree.2. The sulfur content and the ability of sulfur assimilation of plant leaves is different in greenland system. The sulfur content is different in the same degree polluted zone, and that of coniferous trees is less than that of evergreen broad-leaved plants, and that of evergreen broad-leaved plants is less than that of deciduous broad-leaved plants, and that of shrub is less than that of trees. The results also show that the sulfur content of the same species plant is different among different degrees polluted zones, and the ability of absorbing sulfur of different species plant is different, and in all of these, that of shrub is less than that of trees.