中国特有植物巴山榧树的种群结构与动态  

Population structure and dynamics of Torreya fargesii Franch.,a plant endemic to China

作　　者：江波[1] 周先容[1] 尚进[1] 汪建华[1] 宋航 秦明一[1] 刘雪凝[1] 王庆[1] JIANG Bo;ZHOU Xianrong;SHANG Jin;WANG Jianhua;SONG Hang;QIN Mingyi;LIU Xuening;WANG Qing(College of Life Science and Technology, Yangtze Normal University, Fuling 408100, China)

机构地区：[1]长江师范学院生命科学与技术学院,涪陵408100

出　　处：《生态学报》2018年第3期1016-1027,共12页Acta Ecologica Sinica

基　　金：国家自然科学基金项目(31470568)

摘　　要：为了掌握中国特有裸子植物巴山榧树的种群现状,预测种群数量动态趋势,以分布于重庆、四川、陕西、湖北、安徽、河南和甘肃等省市的15个地点的残存巴山榧树种群为对象,建立巴山榧树种群径级结构和高度级结构图,编制种群静态生命表,绘制种群存活曲线、死亡率和消失率曲线,同时结合谱分析方法分析种群数量动态变化。结果表明:巴山榧树种群密度较低,平均为5.33株/100m^2,其中神农架种群(SN)密度最高,为9.58株/100m^2,城口种群(CK)密度最低,为2.75株/100m^2。径级结构中低龄级个体占有较高的比例,种群表现为增长型年龄结构;不同局域种群的径级结构差异明显,除宝兴种群(BX)外,其余种群的径级分布不完整。高度级结构中低于6m的个体占88.74%,绝大多数个体处于群落灌木层。种群的生命期望在不同龄级间波动明显,第3、7龄级的生命期望较低。巴山榧树种群存活曲线趋于Deevey-Ⅲ型;死亡率曲线和消失率曲线变化趋势一致,均在第3、7龄级出现峰值。巴山榧树种群的数量动态除受基波的影响外,在3、5、7龄级还显示出明显的小周期波动。巴山榧树为长寿命孑遗植物,呈岛屿化斑块分布,种群规模小,自然更新能力差,面临灭绝的危险,应及时加以保护。Torreya fargesii is an endangered species that is endemic to China and under second-class state protection. Our previous studies indicated that T. fargesii is distributed from the Qinling, Dabashan, Qionglaishan, and Daloushan mountains to the Wushan, Wulingshan, and Dabieshan mountains, which are located in subtropical regions 800-2700m above sea level. Although T. fargesii has a wide distribution and occurs in many different locations, most populations have only a few individuals and occupy a small area. To better understand the status of T. fargesii populations and propose a protection strategy, we investigated the population structure and dynamics of stands across the region. Plots that covered a total of 18000m2 were established at 15 sites in Chongqing, Sichuan, Shaanxi, Hubei, Anhui, Henan, and Gansu. Diameter-and height-class structure diagrams and a static life table were created, and the mortality and disappearance rates, as well as survivorship curves, were determined. Spectral analysis was used to analyze dynamic changes in population quantity. The findings showed that T. fargesii has a low population density, averaging 5.33 plants/100m2. Population density was highest in Shennongjia （9.58/100m2） and lowest in Chengkou （2.75/100m2）. The diameter-class structure of T. fargesii showed an expanding age structure, with a higher percentage of younger age-class individuals. There were variations in the diameter-class structure among the different populations and the diameter-class distributions of all populations were incomplete （i. e., all size classes were not represented）, except in the Baoxing population. Within the height-class distribution of the T. fargesii populations, individuals of less than 6m accounted for 88.74% of all trees, and most individuals were within the shrub layer at their respective sites. The populations＇ life expectancy rates varied greatly among the different age classes, and the life expectancy of the third and seventh age classes were relatively low. The survivorsh

关 键 词：巴山榧树 种群密度 径级结构 高度级结构 静态生命表 存活曲线 谱分析 

分 类 号：Q948.1[生物学—植物学]