Response Of Plant Phenology To Urban Land Surface Temperature In Changchun

With the acceleration of global urbanization and industrialization,city becomes a specific region of high density population,high speed economic development,high energy consumption and heavier air pollution.It has a great change of climate in city,especially a significant effect of the urban heat island phenomenon,with high speed urbanization.The temperature difference is not only arised between the city and the suburb,but also appeared in the center of city.Plant phenology,which is sensitive to the climate change and facile to observation,can directly reflect the changes of climate.However,the recent study about the relationship between city climate and plant phenology was focused on the analysis via time scale.In this paper,the relationship between plant phenology and location climate will been analyzed at space scale utilizing the sensitivity of plant phenology to climate.It is benefit to reveal the distribution of the urban high temperature region and carry out the project to reduce its effect in time.It is significant to improve the urban living environment for future.In this paper,we analyze the variety of land surface temperature in Changchun urban region by the weather data of Changchun timing from October in 2007 to September in 2008, obtained from the eleven climate encrypted station.It is demonstrated that the land surface temperature in main urban region of Changchun is significantly different.The difference is reached to 6.21℃at January in 2008;and it is more than 3.0℃at December in 2007 and February in 2008,The temperature difference is stable and relatively smaller than that at other months;it is not a significantly changes of location to higher or lower temperature regions.Furthermore,the data of remote sensing image,obtained from Landsat5 TM at September 30,2007,was analyzed and carried out to inversion of land surface temperature to reveal the space distribution of land surface temperature in Changchun.In the urban,the high temperature region is mainly distributed at west and north in Changchun,containing of Kuancheng district, the southwest of Lvyuan district,and the east and north of Erdao district.In addition,there are several high temperature region along the traffic transport lines.The low temperature regions distributed around the water areas in the city center,containing of low temperature center at South Lake and low temperature band along Yitong River.The suburban around the city center shows the relative lower temperature.Finally,this paper analyzes the phenology difference of six woody plants(Syringa amurensis Rupr.,Ulmus pumila L.,Forsythia suspensa(Thunb.) vahl.,Prunus salicina Lindl, Salix babylonica Linn.and Populus canadensls Moench.) observed among April to May in 2008.Then,the space distribution of different plants has been analyzed by the software ARCGIS 9.0.Comparing the space distribution of phenology and land surface temperature,it is obtained the relation between plant phenology and urban land surface tempreture space distribution.For plants of Syringa amurensis Rupr.,Prunus salicina Lindl,Ulmus pumila L. and Forsythia suspensa(Thunb.)vahl.,it is found that the space correlation between abloom ratio and surface land temperature.Furthermore,for plants of Salix babylonica Linn.and populus canadensls Moench.,it is shown a highly consistency between leaf outspread ratio and space distribution of land surface temperature.