植物生态学报 ›› 2018, Vol. 42 ›› Issue (12): 1145-1153.DOI: 10.17521/cjpe.2018.0184

• 研究论文 • 上一篇    下一篇

河北小五台山青杨种群中雌雄群体的空间分布及其成因

蒙振思1,向卫2,苏国岿1,李大东1,董廷发1,彭进友1,李晓东3,龚小平3,梁宁3,胥晓1,*()   

  1. 1 西华师范大学西南野生动植物资源保护教育部重点实验室, 四川南充 637009
    2 西华师范大学国土资源学院, 四川南充 637009
    3 小五台山国家级自然保护区, 河北蔚县 075700
  • 收稿日期:2018-07-31 修回日期:2018-09-02 出版日期:2018-12-20 发布日期:2019-04-04
  • 通讯作者: 胥晓
  • 基金资助:
    国家自然科学基金(31170389);国家自然科学基金(31370596)

Spatial distribution of male and female Populus cathayana populations and its drivers in Xiaowutai Mountains, Hebei, China

MENG Zhen-Si1,XIANG Wei2,SU Guo-Kui1,LI Da-Dong1,DONG Ting-Fa1,PENG Jin-You1,LI Xiao-Dong3,GONG Xiao-Ping3,LIANG Ning3,XU Xiao1,*()   

  1. 1 Ministry of Education Key Laboratory of Southwest China Wildlife Resources Conservation, China West Normal University, Nanchong, Sichuan 637009, China
    2 College of Land and Resource, China West Normal University, Nanchong, Sichuan 637009, China
    3 Xiaowutai Mountains National Nature Reserve, Yuxian, Hebei 075700, China
  • Received:2018-07-31 Revised:2018-09-02 Online:2018-12-20 Published:2019-04-04
  • Contact: Xiao XU
  • Supported by:
    Supported by the National Natural Science Foundation of China(31170389);Supported by the National Natural Science Foundation of China(31370596)

摘要:

为揭示雌雄异株植物种群的空间分异现象的内在原因, 以河北小五台山天然青杨(Populus cathayana)种群为研究对象, 采用平均最近邻指数、核密度、方差分析等方法分析了青杨雌雄群体的聚集程度、群体密度和分布格局以及其与到河岸的距离(河距)、海拔和土壤理化性质间的内在关系。结果显示: 1)青杨种群总体上沿金河沟呈狭长带状集聚分布, 中海拔区域个体数量最多, 密度最大; 2)随海拔增加, 雌雄个体数与密度均表现“先增后减”的特点, 而平均胸径的变化正好相反; 3)海拔对性比具有显著影响: 低海拔区域(1 300-1 400 m)偏雌, 中低海拔区域(1 400-1 500 m)偏雄, 其他海拔段的性比接近1:1; 4)随河距增加, 雌雄个体数、密度和平均胸径均表现出逐渐减少或减小的特点, 并且雌株优势分布区内的土壤有机质和全氮含量显著高于雄株优势分布区; 5)局部区域由于海拔和河距改变了土壤理化性质和生长环境, 导致了该区域内的性比发生偏倚。上述结果表明, 青杨雌雄群体的空间分布、动态变化以及性比受海拔、河距以及所在区域的土壤理化性质的综合影响, 雌雄植株在资源需求和环境适应力方面存在的差异会导致局部区域内的性比发生偏倚。

关键词: 青杨, 胸径, 到河岸的距离, 性比, 土壤理化性质

Abstract:

Aims Spatial segregations between male and female populations of dioecious plants has been increasingly reported in recent years. However, the drivers underlying these segregations have not been fully discussed. Here, we explored the factors driving the spatial segregation between male and female populations of Populus cathayanadistributed in Xiaowutai Mountains of Hebei Province, China.

Methods The male and female P. cathayana trees with diameter at breast height (DBH) larger than 9 cm (representing individuals with sexual maturity) were investigated and the soil physical and chemical properties of each individual were analyzed. The methods of average nearest neighbor index, kernel density estimation and analysis of variance (ANOVA) were employed to analyze the aggregation degree, population density and distribution pattern of male and female P. cathayana populations and their relationships with distance from the river, altitude and soil properties.

Important findings Firstly, P. cathayanapopulation was distributed along the Jinhegou River in a long and narrow belt, with the largest number of individuals and the highest density in the middle altitude area. Secondly, both the number and density of female and male trees increased first and then decreased with the increase of altitude, whereas the change of average DBH was opposite. Thirdly, altitude had a significant effect on sex ratio. The sex ratio was female biased in the low altitude area (1 300-1 400 m), male biased in middle-low altitude areas (1 400-1 500 m), and close to 1:1 in other areas. Fourthly, with the increase of distance from the river, the number, density and average DBH of females or males gradually decreased. Moreover, the content of organic matter and total nitrogen in the dominant distribution area of female trees was significantly higher than that of males. Lastly, because the variation of altitude and distance from the river changed soil physical and chemical properties and growth environment of P. cathayana trees in some areas, the sex ratio was biased. These results indicated that the spatial distribution, dynamic variation and sex ratio of male and female P. cathayana populations were greatly affected by altitude, distance from the river and soil physical and chemical properties. Because of the differences in resource demand and environmental adaptability between male and female populations, the sex ratio will be biased in some area.

Key words: Populus cathayana, diameter at breast height, distance from river, sex ratio, soil physical and chemical properties