濒危植物小黄花茶种群数量结构与生存潜力分析

Population Structure and Survival Potentiality Analysis of Endangered Camellia luteoflora

摘要:

为了解濒危植物小黄花茶(Camellia luteoflora)的生长特征和生存状况，对贵州赤水市国家级桫椤自然保护区内小黄花茶进行全域资源清查，采用样方法调查小黄花茶每株植物高度和地径，统计分析了种群数量及结构特征，并采用径级对应龄级，以0.5 cm地径间隔划特定年龄分组，共分Ⅰ~XV径级，绘制静态生命表分析种群生存潜力和发展趋势。结果表明，调查共发现小黄花茶545株，不同小生境中小黄花茶数量差异大，最少24株，最多120株；种群地径小于0.5 cm且高度低于0.5 m个体存活数量极少，平均地径0.5~2 cm维持最大种群数量；Ⅰ~Ⅱ龄级(0~1.0 cm)种群死亡率和消失率急剧上升而生命期望值急剧降低，II~XV龄级(≥0.5 cm)种群死亡率和生命期望值趋于平缓，消失率呈现较大波动但总体趋于平缓；种群数量结构和存活曲线表明该种群趋近于Deevey-Ⅰ型，属衰退型种群。小黄花茶种群幼苗数量严重不足，种群自我更新困难，现存种群干扰压力大，种群衰退趋势明显，急需加强种群保育。

Abstract:

In order to understand the growth characteristics and survival status of the endangered Camellia luteoflora, an inventory of C. luteoflora resources was carried out in Chishui Alsophila National Nature Reserve, Guizhou Province. The height and ground diameter of each plant were investigated by sampling method, and the population number and structural characteristics were statistically analyzed. The population was divided into specific age groups with 0.5 cm diameter interval and classified into 5 diameter class from I to XV. A static life table was drawn to analyze the survival potential and development trend of the population. The results showed that a total of 545 individuals of C. luteoflora were found in the survey, the number varied greatly in different niches, ranging from 24 to 120. The number of individuals with ground diameter less than 0.5 cm and height less than 0.5 m were very few, and the maximum population was maintained with average ground diameter of 0.5- 2 cm. The mortality and extinction rates of I-II age class (0-1.0 cm) population increased sharply, while the life expectancy decreased sharply. The mortality and life expectancy of II-XV age class (≥0.5 cm) population tended to be flat, while the extinction rates fluctuated greatly but generally tended to be flat. The population structure and survival curve showed that the population was close to Deevey-I type, belonging to the declining population. Therefore, the seedling number of C. luteoflora population was seriously insufficient, the population self-renewal was difficult, the existing population interference pressure was large, showing obvious population decline trend, it was urgented to strengthen the population conservation.