梵净山冷杉(Abies fanjingshanensis)是国家一级保护植物,是中国贵州特有的珍稀濒危植物.通过实地踏查在梵净山冷杉主要分布地选取2个斑块,调查分析其种群年龄结构特征,量化确定种群结构类型,并运用时间序列模型预测种群数量动态,对比不同生境下的异同点,以揭示梵净山冷杉的种群结构及动态特征.结果表明:(1)梵净山冷杉种群属于增长型,Vpt′=0.005 9,表明该种群趋近于稳定型;种群结构在发展过程中存在一定的波动性,种群生长前期个体数多于生长后期;存活曲线趋于Deevey-Ⅲ型;幼苗不足和幼树、小树的死亡率高是种群濒危的重要原因.(2)时间序列预测分析表明,梵净山冷杉种群具备一定的恢复能力,未来2、4和6个龄级时间后种群个体数均呈现小幅度的增加趋势.(3)不同生境条件下,种群结构差异不大,生境一的种群结构增长性略大于生境二.%As the first class of nationally protected plants,Abies fanjingshanensis is a rare and endangered plant endemic to Guizhou with very rare population. Two patches were chosen to reveal the characteristics of the population structure in this study. Age structure was analyzed,and the population structure type was determined quantitatively. The population dynamics were predicted by time sequence model, and differences and similarities in the habitats were compared. The results showed that:(1)The population of A. fanjingshanensis presented as a growing type,and Vpt′=0.005 9,which showed its population tended to be a stable type. The population structure showed volatility during development, and there were more trees in early growth stage than that in late growth stage. The survival curve approached to Deevey-Ⅲ. The shortage of young seedlings and the high mortality of young trees and sapling trees may be important reasons of being endangered. (2)The time sequence model predicted that A. fanjingshanensis population was able to keep stable,and the amount of population would have a light rising tendency in the coming 2,4 and 6 age classes. (3)In different habitats, the characteristics of population structure had little difference. The growth of population structure in habitat 1 was slightly more than that in habitat 2.
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