Discoloration Law And Application Research Of Autumn Color Trees In Nanjing's Typical Green Space

The leaves of autumn color trees is green in summer,while in autumn or winter,it transform into other colors such as red,yellow or brown.This phenomenon get a varity of changes to a garden's color.For a long time,researchers have focused on the research on the germplasm resources and planting application of autumn color trees.While,the research of relationship between the color sequence of autumn color trees and the change of temperature and environment is absenced.Grasping the relationship between the color sequence of autumn color trees and the change of temperature and environment can help us better use of autumn color trees to build a richer autumn landscape.To research the relationship,choosing some urban green spaces in Nanjing,where have different characteristic in application of autumn color trees.The urban green spaces are:'Xiaotaoyuan' park,'Xiamafang' park,'Pukou' park,'Xiuqiu' park,'ZhengHe' park and'Daxinggong' square.In all this urban green spaces,I choose 21 sample plots to observing and recording,to research the following aspects of content:(1)The species data,the number of tree species,the height of the tree species and the diameter of the DBH(shrub for the ground diameter)and the crown(shrub for the coverage area)were recorded.The relevant ecological and mathematical formulas were used to calculate the Comprehensive advantage ratio,and the focus of the application of autumn color trees.(2)The continuous observation and recording of the autumn color trees and summarize and analyze the discoloration sequences of the various trees.At the same time,describe their color change status as can as possible.(3)Combined with temperature changes on leaf color discoloration time series of comparative study and found that the average low temperature range of 15-19 ? and 8-10 ? has important influence on the beginning of discoloration and rapid completion of Nanjing autumn leaves.(4)The results showed that the external growth conditions had different effects on the ornamental value of autumn leaves in a kind of autumn tree species.And according to these effects,the paper puts forward the reasonable way to improve the ornamental value of autumn leaves in order to make full use of the influence of different environment and create a landscape season with more ornamental value and diverse functions.