| Rhododendron which is a large variety of species has a rich and diverse patterns and a long flowering period. It is colorful and varied, with the characteristics of adaptability and quality of resources of wild flowers. Based on the investigation of the distribution and characteristics of community, anatomical structure and photosynthetic characteristics of five species of Rhododendron of the TaiBai Mountain , analyzed the difference of community of five species of Rhododendron in different habitat conditions, as well as the relationship between anatomical structure and photosynthetic characteristics for ecological adaptability of different kinds of Rhododendron, the main results showed that,1. The result showed that, five species of Rhododendron distribute between 2000m and 3700m elevation in the TaiBai Mountain. The R. capitatum distributed in alpine shrub, and R. taibaiense found in 3000-3400m under Larix chinensis forest, R. clementinae subsp. aureodorsale, R. purdomii and R. concinnum distributed in the 2000-3200m under Betula albo-sinensis and Betula utilis forestry.2. Through measurement the light response curve, the light saturation point of five species of Rhododendron were between 500 and 1000μmol·m-2·s-1. The Pn of R. clementinae subsp. aureodorsale and R. purdomii increased significantly with the illumination intensity. With the illumination intensity increasing, the Pn of R. capitatum increased first and then decreased. The Pn of R. taibaiense changed slightly. R. capitatum distributed in alpine shrub, has high light saturation point and light compensation point, high light adaptability and poor shade tolerance. R. taibaiense found in 3000-3400m under Larix chinensis forest, has lower light saturation point and higher light compensation point, weak light adaptability and narrower ecological amplitude; R. clementinae Forrest. subsp. aureodorsale, R. purdomii and R. concinnum distributed in the 2000-3200m under Betula albo-sinensis and Betula utilis forestry, was low light compensation point, strong shade-tolerant and wide ecological amplitude.3. Through meansurement of chlorophyll content, the chlorophyll content of five species of Rhododendron was between 1.561 mg/g and 0.928 mg/g. At the P < 0.05 level, the chlorophyll content of five species of Rhododendron had significant differences. The R. concinnum had the highest level of chlorophyll content, and the R. capitatum and R. clementinae subsp. aureodorsale had the lower level. The rate of chlorophyll a and ?chlorophyll b were between 2.633 and 1.200. The rate of R. capitatum was the minimum while the R. concinnum was the maximum. At the P < 0.05 level, significant differences between R. capitatum and R. clementinae subsp. aureodorsale was extremely significant, and slightly with other species. The result showed that the chlorophyll content and the rate of chlorophyll a/b had negative role.4. Through observation the slices, stockade tissue and sponge tissue of five species of Rhododendron had obviously distinguish. They had typically different face. The lower leaf epidermis of R. capitatum was papillary, and the R. taibaiense, R. clementinae subsp. aureodorsale and R. purdomii had obviously double epidermis. The leaf of R. capitatum and R. concinnum were densely covered scales, and the lower leaf epidermis of R. clementinae subsp. aureodorsale was covered with yellow brown furriness fur. All five Rhododendrons had obviously corneous layer.5. By observation epidermal cells under optical microscope were found that, the stomas of five species of Rhododendron were in the lower leaf epidermis and the ways of distribution were obviously different. The stoma of R. taibaiense and R. purdomii had aggregate distribution, and R. clementinae subsp. aureodorsale, R. concinnum for random distribution. The stomas of R. capitatum were distributed around the scale of lower leaf epidermis with a shape of wreath. The stoma density of five species of Rhododendron was between 210 and 520/mm2.6. The leaf thickness of five species of Rhododendron was between 272.61μm and 483.95μm. The ratio of palisade tissue and spongy tissue of five species of Rhododendron were between 0.28 and 0.72, which much less than 1, they were shade-tolerant plant, and had different vascular bundle. The midrib thickness and diameter of the biggest trachea of R. taibaiense and R. clementinae subsp. aureodorsale were stronger than others.7. The crystal cell could obviously found in the anatomical structure of five species of Rhododendron, and the R. capitatum and R. concinnum were especially significant.8. Though analysis the plasticity found that, the plasticity characteristic of epidermis and mesophyll were between 0.54 and 0.35, and they were higher than midrib thickness and leaf thickness. The average plasticity of five species of Rhododendron from more to less were R. taibaiense>R. capitatum>R. concinnum>R. purdomii>R. clementinae subsp. aureodorsale. The R. clementinae subsp. aureodorsale had the minimum plasticity which showed that it had lower ecological suitability.
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