Study On The Leaf Functional Traits Of Davidia Involucrata At The Houhe Nature Reserve In Hubei

Davidia involucrata is an endangered endemic single species genus plant and is enlisted as the national Class 1 endangered and protective plant species in China. Plant functional trait has been a hot topic in ecological research in research in recent years. It is the plant trait which can respond the change of living environment and have an effect on ecosystem function. Because leaf functional traits are most closely related with plant biomass and efficiencies of resource acquisition and utilization by plants, it is of great ecological significance to study the leaf functional traits in D. involucrate for conservation of this important plant species. This paper studied on the correlation of main leaf functional traits through Pearson correlation analysis, investigating on Davidia involucrate communities at the Houhe Nature Reserve in Hubei. The main leaf functional traits between Davidia involucrata and other trees and at different age classes of Davidia involucrata were also compared, through independent-samples t-test. This paper chose these leaf functional traits to study, such as leaf construction cost based on mass(CCm),leaf construction cost based on area(CCa),specific leaf area(SLA),leaf nitrogen content based on mass(Nmass),leaf nitrogen content based on area(Narea),maximum photosynthetic rate(Amax),dark respiration rate(Rd),light compensation point(LCP) and light saturation point(LSP). The main results were as follows:1,Specific leaf area (SLA) had significant and negative correlations with the mass-based (CCm) and area-based (CCa) leaf construction cost and area-based leaf nitrogen content (Narea) (p＜0.01), while had significant and positive correlations with the mass-based leaf nitrogen content (Nmass) (p＜0.01).2,A higher SLA and mass-based leaf nitrogen concentration (Nmass) but lower CCm, CCa, and area-based leaf nitrogen concentration (Narea) were found in D. involucrate as compared with other tree species, suggesting a more efficient capture of limiting resources in D. involucrate than in other species. Competitive advantage of Davidia involucrata indicated that interspecific competition may not be the main cause of its endangerment.3,CCm,CCa,Amax,Rd,LCP and LSP were all ranked in the order of third class trees> second class trees> first class trees, but SLA showed a reverse sequence (p<0.05). Results in this study suggest that D. involucrata has a flexible light-adaptation strategy in its early growth phase as first class trees under the shade, but becomes shade-intolerant when growing into second class trees. Light limitation is likely one of the major constraints in population growth of D. involucrate.