The Characteristics Of20Dominant Plant Functional Traits In Evergreen Broad-Leaved Forest In Daming Mountain Nature Reserve,Guangxi

Through the combination of plant traits along a resource gradient where the dynamic changes to adapt to the environment,the combination of multiple traits can determine the relationship between plants,it also determine interactions among the plant species and community and ecosystem.This study was selected the important value in the top20of evergreen broad-leaved forest in Guangxi Daming Mountain Nature Reserve as the research object,after investigated the3.2hm2plots,mainly on the following aspects:(1) Measured leaf functional traits and other functional traits in each plant, to compare the correlation and changes between functional traitsand;(2) The20species were divided into three group by using Hierarchicak Cluster Analysis, to study whether there is relationship between plant functional traits in threee different functional groups or not;(3) Measured the leaf N,leaf P, N/P of20species plants, to study whether the plant in Daming Mountain was limited by N, P elements or not.(4) Based on different slope positions and different leaf collection of plants, to study whether the site conditions will have an impact on the relationship between functional traits of plants. The results show that as follows:There are varying degrees of correlation between functional traits in Damingshan evergreen broad-leaved forest. Leaf tissue density, leaf area, leaf thickness, leaf size was significantly negatively correlated,because it by reducing leaf tissue density to ensure the supply of nutrients to cope with poor soil environment; specific leaf area was significantly negatively correlated with leaf dry matter content of the stems density and significantly positively correlated with leaf nitrogen content,leaf phosphorus content, leaf potassium content, indicating that the higher specific leaf area,lower stem density is productivity and has a strong ability to absorb nutrient; plant chlorophyll content, leaf nitrogen content, leaf phosphorus content was significantly negatively correlated, indicating that plant by absorbbing nutrient during photosynthesis weakened to survive adverse environment; leaf dry matter content and leaf tissue density, leaf phosphorus content and chlorophyll content significantly positive correlation,leaf photosynthetic capacity diminished because of higher leaf water content; phosphorus content of the leaves and leaf nitrogen content and leaf potassium content was significantly positively correlated; stems density, leaf thickness, leaf area, height to diameter ratio was significantly positively correlated, indicating little change in diameter at breast height, with the increase in plant height, plant stem density also increases. Therefore, the evergreen broadleaf forest of Damingshan has strong water balance and the ability to retain elements,by strong linkages between the respective functional traits at the same time, it well adapted to he barren mountain environment.To Study of these functional traits, the result shows that variation range of leaf area, leaf size, leaf potassium content and crown, followed by leaf thickness, leaf tissue density, specific leaf area, leaf nitrogen content, leaf phosphorus content and diameter at breast height,the range of tree height, stem density, ratio of height to diameter and leaf dry range of content and chlorophyll is the minimum.This shows that the response to the same environment and adaptability is different of different plant functional traits.(2)20kinds of evergreen broad-leaved woody plant was divided into three functional groups.The texture of the leaves of three functional groups were paper,thin leathery; leathery; leathery, papery. Because the water content of paper leaves is higer than leathery leaves, A functional group has a larger specific leaf area,B functional groups has smaller leaf area and larger leaf tissue density. The functional traits of A functional group is the best in the three functional groups,B functional group is slightly better than the C functional groups,because of Equilibrium effects and Interspecific similarity.The correlation between three functional groups show that as follows:leaf density and stem density showed significant differences in the three functional groups; specific leaf area have significant difference between A functional group and B functional group; leaf dry matter content was a significant difference in A functional group and B functional group,B functional group and C functional group,because of Ecological compensation effect.(3) in the20dominant plants, leaf nitrogen content and leaf phosphorus content are no significant regular pattern, but the size of the content with N/P floating at the same time. Leaf nitrogen content was significantly lower than the whole of China regional and global region, but close to the evergreen woody plants at the Chinese region.leaf phosphorus content was more than evergreen woody and broadleaf woody at China’s regional, but less than the entire Chinese regional and global regions. N/P was significantly higher than N/P of the global region,similar to the Chinese region of N/P, smaller than evergreen woody and broadleaf woody at the Chinese region. This shows that the productivity of plant at Guangxi Darning Mountain is mainly restricted by nitrogen.In the three functional groups, there is not much relationship between leaf nitrogen content and leaf phosphorus content.Three functional groups are respectively limited by N,P,N and P.(4) in different slope positions, there are some difference between part of the plant functional traits, such as the leaf dry weight, leaf dry matter content, leaf density, specific leaf area and chlorophyll content,because of light intensity,water content,nutritional elements.There are no difference in leaf functional traits between Different sampling direction.