| Dendrobenthamia angustata (Chun) Fang var. wuyishanensis (Fang et Hsieh) Fang et W. K. Hu is a plant which have high potential value in the landscape gardening. Predecessors has carried out seed breeding technology research about the tree, In the physiological and ecological characteristics of research mainly in adversity physiology research.But their eco-physiology characteristics, suitable environment of growth and the cultivated mode in the landscape gardening are still were unknow. This research studied systematically ecological properties of photosynthesis of the tree. Then analysised their shade endurance and drought resistance, and probe into the cultivated mode in the landscape gardening.After the research of photosynthetic physiology characteristics,the resultsshowed as following:1. Under controlles conditions which set up gradient of photosynthetically active radiation with redblue source,and draw light curve of this tree.Based on the analysis of these light curve,the result is that:the light compensation point of Dendrobenthamia angustata (Chun) Fang var. wuyishanensis (Fang et Hsieh) Fang et W. K. Hu was approximately26.02μmol photons·m-2·-1and the light saturation point was670.01μmol photons·m-2·s-1in spring, the light compensation point of Dendrobenthamia angustata (Chun) Fang var. wuyishanensis (Fang et Hsieh) Fang et W. K. Hu was approximately33.59μmol photons·m-2·s-1and the light saturation point was530.21μmol photons·m-2·s-1in summer, the light compensation point of Dendrobenthamia angustata (Chun) Fang var. wuyishanensis (Fang et Hsieh) Fang et W. K. Hu was approximately30.72μmol photons·m-2·s-1and the light saturation point was517.91μmol photons·m-2·s-1in autumn.Dendrobenthamia angustata (Chun) Fang var. wuyishanensis (Fang et Hsieh) Fang et W. K. Hu have low light saturation point, belongs to the negative plants. Light compensation point slightly higher, for illumination have certain requirements, but not in direct sunlight resistance, higher temperatures will lead to stomatal closure.2. According to the diurnal variation of net photosynthetic rate of the Dendrobenthamia angustata (Chun) Fang var. wuyishanensis (Fang et Hsieh) Fang et W. K. Hu, the results showed that:presented the double-peak curve type in spring, summer and autumn. The spring peak appeared at9:00and15:00respectively, peak were9.7328μmol CO2·m-2·s-1and7.0333μmol CO2h·m-2·s-1; The spring peak appeared at10:00and16:00respectively, peak were2.40600333μmol CO2h·m-2·s-1and1.9108μmol CO2·m-2·s-1; The spring peak appeared at9:00and15:00respectively, peak were2.72710333μmol CO2h·m-2·s-1and1.63530333μmol CO2h·m-2·s-1.3. In the nature condition, the daily variation of transpiration rate of Dendrobenthamia angustata (Chun) Fang var. wuyishanensis (Fang et Hsieh) Fang et W. K. Hu is the double-peak curve type. In spring the transpiration rate is2.5013mmol H2O·m-2·s-1; In summer the transpiration rate is2.2544mmol H2O·m-2·s-1; In autumn the transpiration rate is very low.4. In spring the stomatal conductance of Dendrobenthamia angustata (Chun) Fang var. wuyishanensis (Fang et Hsieh) Fang et W. K. Hu is the double-peak curve type. The first peak of stomatal conductance is0.8575mmol H2O·m-2·s-1at10:00, The second peak of stomatal conductance is0.07947mmol H2O·m-2·s-1at15:00; In summer the transpiration rate is2.2544mmol H2O·m-2·s-1; In summer the stomatal conductance of Dendrobenthamia angustata (Chun) Fang var. wuyishanensis (Fang et Hsieh) Fang et W. K. Hu is the one peak curve type. The peak of stomatal conductance is0.0409mmol H2O·m-2·s-1at14:00. In autumn the stomatal conductance is very low.5. In spring, Dendrobenthamia angustata (Chun) Fang var. wuyishanensis (Fang et Hsieh) Fang et W. K. Hu has the lightest utilization efficiency, and the follow is summer, the autumn is the lowest. The light utilization efficiency of Dendrobenthamia angustata (Chun) Fang var. wuyishanensis (Fang et Hsieh) Fang et W. K. Hu in spring, summer and autumn was0.53%,0.29%and-6.14%.6. In spring, Dendrobenthamia angustata (Chun) Fang var. wuyishanensis (Fang et Hsieh) Fang et W. K. Hu has the hightest water use efficiency, and the follow is summer, the autumn is the lowest. The water use efficiency of Dendrobenthamia angustata (Chun) Fang var. wuyishanensis (Fang et Hsieh) Fang et W. K. Hu in spring, summer and autumn was4.348lμmol CO2·mmol-1H2O,1.6946μmol CO2·mmol-1H2O andl.6192μmol CO2·mmol-1H2O. |
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