贵州茂兰珍稀濒危植物四药门花种群特征.

Loropetalum subcordatum(Hamamelidaceae)is one of rare and endangered species, and endemic species to China. The population structure is an element issue for its protection. The innovation of this paper was to analyzed population characteristics of L. subcordatum in Maolan Karst Natural Reserve, Guizhou Province and to provide countermeasure for protecting L. subcordatum. We investigated the population diameter structure, static life table and studied survival curve of L. subcordatum based on the survey. The results showed were as follows:(1)Proportion of the individual number of L. subcordatum was diameter Class Ⅳ(2.5 cm≤DBH<5 cm), which accounted for 27.0%, and the seedling bank accounted for 24.7%. Therefore, the population was stable with lots of seedling and young trees pool.(2)Diameter class Ⅱ(h>1.3 m, DBH<1 cm)and Class I(h<1.3 m)has the highest life expectancy. At Class V(5 cm≤DBH<7.5 cm), there was an inflection point of life expectancy. In Class I, Class Ⅱ, Class Ⅲ and Class IV, the life expectancy of L. subcordatum decreased with the age increasing. In Class VI, Class Ⅶ, Class Ⅷ and Class IX, the life expectancy of L. subcordatum was increased firstly and then decreased with the age increasing.(3)Class V had the highest mortality and disappeared rate, because of the environmental sieve especially water stress. The trend of mortality curve was consistent with disappeared rate curve and the curve was up and then slightly down with aging.(4)The survival curve was monotone decreased except for Class Ⅱ to Class Ⅲ(1 cm≤DBH<2.5 cm).(5)To protect the species more effectively, the best way is in-situ conservation(on-site maintenance). The medium diameter class of L. subcordatum needs more attention to tending. The L. subcordatum population in Maolan can have a better recovery potential, as long as continue to maintain the reforestation politics. [ABSTRACT FROM AUTHOR]