| City is a complex system which composed of the population, natural environment, socio-economic activity.With the population growth, economic development, urbanization, and the number of car rised, the urban ecological problems are very critical, such as environmental pollution increased , urban heat island effect raised, harmful caused by acid rain, the decrease of biodiversity.That not only impacted the quality of living condition for the residents,but also threatened the ecological security of the urban.According to the problems caused by urbanization,it important to re-recognize the function of forest ecosystems,which is the improve and maintain the urban environment and play an irreplaceable role of the city sustainable development.Urban forest is an important part of the city self-purification system,an effective way to increase the green GDP of the city ,an important way to maintain the health and balance of urban ecosystem and the symbol of the city for the level of sustainable development and civilization.The location of research was Fuzhou and Xiamen,from March 2008 for one year.The research object was foundationsl tree species of the urban forest.The project used GXH-3011A CO analyzer and HBD5-SPM4220 handheld tester to measure the consistency of CO and TSP of different spatial position;used the N962 analyzer to the microclimate such as wind speed, temperature, humidity and the volume of the traffic;used LI-6400 to test the diversity of photosynthesis between normal and CO stress on the leaves.The purposes were studying the deposition of the species to CO and TSP;exploring the effects to atmospheric pollutants from micro-climate;discussing the atmospheric pollutants deposition rules of the different plant community structure and the effect of the CO stress for photosynthesis.The research provides the scientific foundation for guiding scientific management of urban forest tree species selection, structural configuration and the health management of urban forest sustainable.The conclusions were as follow:(1) The annual average concentration of CO of Fuzhou as follows : spring> summer> winter> autumn;the annual average concentration of CO of Xiamen as follows : autumn> summer> winter> spring. The percentage of the four seasons to reduce CO concentration of Fuzhou as follows: winter> autumn> summer> spring; The percentage of the four seasons to reduce CO concentration of Xiamen as follows: winter> summer> autumn> spring.The percentage of purification is higher of Xiamen only in summer, and the others seasons are higher in Fuzhou.(2) The concentration of CO is higher in the the road than that under the trees of the four seasons.The accumulated CO concentrations of a year in Fuzhou is higher than that in Xiamen.The concentration of CO is higher of the blank test without street trees than the others.(3) The seasonal efficacy of the four species in Fuzhou to reduce CO concentration order: Cinnamomum camphora> Mangifera indic> Ficus microcarpa var.pusillifolia> Bauhinia purpurea. Evergreen broadleaved tree species has the higher purification percentage than deciduous species. The seasonal efficacy of the four species in Xiamen to reduce CO concentration order: Delonix regia> Mangifera indic>Ficus altissima> Bauhinia purpurea.(4) The order of seasonal changes of TSP consistency both on the road and under the trees in Fuzhou is :summer> spring> autumn> winte;that in Xiamen is autumn> summer> winter> spring.The seasonal percentage of purification in Fuzhou is :spring> autumn> winter> summer,the seasonal percentage of purification in Xiamen is: spring> winter> autumn> summer.The highest percentage of purification was in spring and summer minimum,and Fuzhou's is higher than Xiamen.(5) The concentration of TSP is higher on the the road than that under the trees. The concentration of TSP is higher of the blank test without street trees than the others. The highest seasonal percentage of purification in spring, summer and autumn is F. microcarpa var.pusillifolia, the highest in winter is M.indic and the minimum of four season is B.purpurea,Fuzhou. The highest seasonal percentage of purification in spring, autumn and winter is F.altissima,in summer the highest is B.purpurea and the minimum is M.indic. All in all the evergreen broad-leaved tree has the better purifying effect than deciduous species.(6) The seasonal diversification laws of CO concentration cumulant in a year for multi-structure of plant is summer> autumn> winter> spring ;and the TSP concentration cumulant in a year is autumn> summer> winter> spring.The concentration of CO was decreased from central of the road to the sidewalk: E> D> C> B> A.The concentration of TSP was higher on both sides ,the cumulative of the year is: E> A> D> B> C.From the result the multi-structure of plant play a significant role to reduce the CO and TSP.(7) The CO percentage of purification for multi-structure of plant is winter> autumn> summer> spring,the order of TSP is spring> winter> autumn> summer.The result is same with single-layer structure of Xiamen.(8) There were some different of the moment that highest emerged for the seasonal CO concentration in multi-structure of plant.The CO concentrations are higher in about 12:00 and the period people go to work that the cars used.There didn't any significant difference of the CO concentrations in the Vertical space. There were an obvious peak of TSP in for season which concentrated in the two vehicles traveling: 10:00 - 12: 00 and 13: 00 - 15:00.(9) The leaves of B.purpurea ware injuried through the CO stress,that were dehydration and leaf chlorosis seriously, the edge of leaves has appeared large area brown necrosis and some white spots.The leaves of B.purpurea which were lighter injuried appear reddish-brown spots on the marginal and had some irregular yellow-green dots.The leaves of F. microcarpa were lesser injuried than B.purpurea,there had some irregular reddish-brown spots. The worst injured were in summer.(10) The net photosynthetic rate(Pn), transpiration rate, stomatal conductance (Gs), intercellular CO2 concentration (Ci)were all inhibited after the CO stress.(11) The CO concentration of the road had power exponential function with traffic and the relative coefficient were higher than 0.75,the relative coefficient of controlled trial were higher of both two location,on the road: R2=0.914,on the sidewalk: R2=0.865.The power exponential function under the trees were lower between the CO concentration and traffic. CO concentration had less relevant with temperature, humidity and wind speed.(12)The experimental data show that the TSP concentration had linear correlation with traffic, the relative coefficient under trees were lower than the road.The TSP concentration of two location of D. regia had lower correlation coefficient.(13) The TSP concentration had inegative linear correlation with humidity.The relative coefficient were higher except the two location of D. regia. When the sprinkler pass ,humidity increased the concentration of TSP is correspondingly reduced. TSPconcentration had less relevant with temperature and wind speed.
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