Researches On The Model Of Leaf Area Index Of Common Landscape Plants In Beijing

With rapid development of economy, the population of city increase suddenly, the urban road and the building are more and more densed, the green area are more and more few. The green space insufficiency has become the latent restriction factor to develop economy and society. This paper aims to the tight situation of the city green area, how to quantify the vegetation quantity of urban ornamental green space more accurately and fastly. These studies could provide the basic data and research achievement on analysis the difference of ecology benefit between different green space. and the reasonable method for the quantitative research on ecology effect of the city afforests. At the same time, it will provide the theory basis for the plant choice and the disposition and the change of plant's spatial distribution.In order to solve these issues existing at present research and application in urban forest/gardens, this paper chose the 40 tree species in Beijing area, such as Pinus bungeana, Fraxinus pennsylvanica, Ailanthus altissima, Platanus occidentalis, Prunus persica 'Duplex', using the digital plant canopy imager CI-110, observe the leaf area index of these tree species. This article was focus on the following probem:· Research theory and methods in the studies of plant leaf area index.· Quantitative relationship between leaf area index and crown diameter and the dbh or high of the 40 urban tree in Beijing· The change of the leaf area index of the 40 urban trees in BeijingThe result showed that: Under the basic same area, there was strong correlation for leaf area index and crown diameter and the dbh or high of the 40 urban trees in Beijing. It is available to develop regression equations to predict leaf area index from crown diameter and the dbh or high of the tree .Different life forms of ornamental plants in this area had agreater difference in their leaf areaindex, and the LAI was not only depended on single leaf area, but also governed by the shape of tree crown and the intensive degree of branches and leaves. According to this experiment measurement result: the leaf area index of seven evergreen arbor trees is 1.50～3.12, the leaf area index of twenty-three arbor tree is 1.4～4.94, the leaf area index often deciduous shrubs is 1.60～2.10.