Population Structure and Spatial Distribution Pattern of a Rare and Endangered Plant Pseudotsuga sinensis

Abstract:

In order to understand the survival status and regeneration mechanism of Pseudotsuga sinensis population, the community structure and spatial distribution pattern in Weining County Nature Reserve for P. sinensis of Guizhou Province were studied. The results showed that the diameter class structure of the population was a typical single-peak type, with more middle-aged individuals and fewer young and old individuals. The dynamic indexes (V_pi=13.49%, V'_pi=0.05%) of population structure showed a growth type, But the growth rate gradually decreased, and the sensitivity to external interference was higher. The survival curve of population tends to Deevey-II type, with the life expectancy decreased monotonously. The mortality rate showed a "V" type with two death peaks, the first appeared in I age class and the second in IX age class. Most of the sample plots showed cluster distribution, while Q2 and Q7 plots showed uniform distribution. The spatial distribution pattern changed from cluster distribution to uniform distribution along the age. Therefore, the main factor of endangered population of P. sinensis was the failure of young individuals to replenish population in time, it was suggested to strengthen seedling tending and promote regeneration of P. sinensis population through moderate disturbance.

Key words:Pseudotsuga sinensis;Population structure;Spatial distribution pattern