大别山五针松种群结构及动态研究

大别山五针松(Pinus dabeshanensis)是大别山区特有种,最大种群分布于安徽省岳西县大王沟。采用空间序列代替时间的方法分析种群结构,编制种群特定时间生命表,绘制死亡率曲线和消失率曲线,并用4个生存函数进行种群的生存分析;同时结合谱分析方法,分析了大别山五针松种群数量的动态变化。结果表明:大别山五针松种群数量少,结构存在波动性。幼苗阶段个体较丰富,幼树阶段个体较少,种群趋于衰退。种群死亡率和消失率曲线变化趋势基本一致,在第5龄级出现峰值。4个生存函数曲线表明,大别山五针松具有前期快速减少、中期稳定和后期衰退的特点。谱分析显示,大别山五针松种群动态除受基波影响外,还具有明显的小周期波动,谐波A3和A4处的周期波动与个体生长有关。

STUDIES ON POPULATION STRUCTURE AND DYNAMICS OF PINUS DABESHANENSIS

Pinus dabeshanensis Cheng et Law (P. dabeshanensis) is an endangered endemic occurring at the Dabieshan Mountains. This species is known from only 4 natural populations. Dawanggou in Yuexi County, Anhui Province, is known as the region hosting the largest population. Because of its small range, few populations, and small population sizes, P. dabeshanensis is considered "endangered" according to the China Species Red List. To obtain fundamental information of population structure and dynamics, we used spatial series substituting for time sery to analyze the population structure. And the time-specific life table, mortality rate, vanish rate as well as the four survival functional curve of the population were calculated, respectively. Additionally, spectral analysis was used to analyze the population dynamics. The results showed that P. dabeshanensis population was extremely small and population structure fluctuated. Although the seedlings were more abundant, young trees were very deficient, which suggested that the population was decreasing. The curves of mortality rate and vanish rate exhibited a similar variation tendency:peak exsisted in the 5th age class period. Four survival functional curves showed that the population decreased rapidly at the early ages, grew stably at the intermediate ages and declined in the late lifespanSpectral analysis of the population showed that the population dynamics had a clear periodic fluctuation in the growth except for the influence of fundamental wave, in which periodic fluctuation in waves A3 and A4 might be related to the individual growth. Based on the population information obtained for P. dabeshanensis, we propose some suggestions for the conservation and efficient management of this endangered species.