Research On The Rule Of Transpiration And Water Consumption Of Three Landscaping Trees In Different Urban Hot Entironment In Beijing

The earlier studies on the rule of transpiration and water consumption of trees aim at those in uniform entironment, but the studies in variational entironment are infrequent. Whether the different hot entironment caused by different underlying surfaces worked on the rule of transpiration and water consumption of trees was studied in this paper aiming on urban entironment. The Complete stochastic grouping was used in this experiment. The conclusion was: (1)the temperature between different underlying surfaces had significant differences in spring, summer and autumn. (2)Diurnal fluctuation of transpiration rate of Sophor-a japonica L. , Ginkgo biloba L. and Koelreuteria paniculata L. seedlings was showing one-peak curve on different underlying surfaces on spring, summer and autumn sunny day, but the time getting to peak value are different in different seasons and on different underlying surfaces. The transpiration rate of Sophora japonica L. seedlings had significant differences on different underlying surfaces from eight to eighteen on spring, summer and autumn sunny day. The transpiration rate of Sophora japonica L. seedlings on YLM underlying surface was 1.1-2.04 times, 1.03-1.4 times and 0.34-1.17 times than that on CP underlying surface. The transpiration rate of Ginkgo biloba L. seedlings had significant differences on different underlying surfaces from eight to eighteen on spring, summer sunny day. The transpiration rate of Ginkgo biloba L. seedlings on CP underlying surface was 1.24-1.43 times and 1.41-1.44 times than that on YLM underlying surface. The transpiration rate of Koelreuteria paniculata L. seedlings had significant differences on different underlying surfaces from eight to eighteen on summer and autumn sunny day. The transpiration rate of Koelreuteria paniculata L. seedlings on YLM underlying surface was 1.35-1.4 times and 1.47-1.56 times than that on CP underlying surface. (3)The WUE of Sophora japonica L. and Koelreuteria paniculata L. seedlings was less on YLM than CP underlying surface, contrarily, the WUE of Ginkgo biloba L. was more on YLM than CP underlying surface. (4)The water consumption of per leaf area per day and year of Sophora japonica L. and Koelreuteria paniculata L. seedlings was more on YLM than CP underlying surface, but the Ginkgo biloba L. seedlings' are contrary. The water consumption of per leaf area per day of Sophora japonica L., Ginkgo biloba L. and Koelreuteria paniculata L. seedlings were 0.73 kg m^-2d^-1 0.48 kg m^-2d^-1和 0.82 kg m^-2d^-1 on YLM underlying surface. The water consumption of per leaf area per day of Sophora japonica L., Ginkgo biloba L. and Koelreuteria paniculata L. seedlings were 0.52 kg m^-2d^-1 0.65 kgm^-2d^-1和 0.67 kgm^-2d^-1 on CP underlying surface. The water consumption of per leaf area per year of Sophorajaponica L., Ginkgo biloba L. and Koelreuteria paniculata L. seedlings were 143.67 kgm^-2 , 122.64 kgm^-2 和173.95 kgm^-2 on YLM underlying surface. The water consumption of per leaf area per year of Sophora japonica L., Ginkgo biloba L. and Koelreuteria paniculata L. seedlings were 116.01 kgm^-2 , 147.12 kgm^-2 和 147.13 kgm^-2 on CP underlying surface.(5)The relativity between transpiration rate and entironment was different on different underlying surfaces in different season. Using the conclusion about the water consumption of per leaf area, if the leaf area of whole tree was found, per year water consumption of whole tree could be calculated. After getting the consumption of whole tree and linking with the rainfall of Beijing, the Sophora japonica L., Ginkgo biloba L. and Koelreuteria paniculata L. could be collocated and irrigated reasonably through the more scientific method.