植物生态学报 ›› 2023, Vol. 47 ›› Issue (4): 506-514.DOI: 10.17521/cjpe.2022.0319

• 研究论文 • 上一篇    下一篇

东阿拉善珍稀濒危植物绵刺种群结构与点格局分析

李晓田, 王铁娟*(), 韩文娟, 张丽, 张慧, 刘晓婷, 刘雅洁   

  1. 内蒙古师范大学生命科学与技术学院, 内蒙古自治区高等学校生物多样性保护与可持续利用重点实验室, 呼和浩特 010022
  • 收稿日期:2022-07-27 接受日期:2022-12-09 出版日期:2023-04-20 发布日期:2022-12-10
  • 通讯作者: *(wtj105@163.com)
  • 基金资助:
    内蒙古自治区科技计划项目(2020GG0124)

Population structure and point pattern analysis of rare and endangered plant Potaninia mongolica in eastern Alxa, China

LI Xiao-Tian, WANG Tie-Juan*(), HAN Wen-Juan, ZHANG Li, ZHANG Hui, LIU Xiao-Ting, LIU Ya-Jie   

  1. College of Life Science and Technology, Inner Mongolia Normal University, Key Laboratory of Biodiversity Conservation and Sustainable Utilization for College and University of Inner Mongolia Autonomous Region, Hohhot 010022, China
  • Received:2022-07-27 Accepted:2022-12-09 Online:2023-04-20 Published:2022-12-10
  • Contact: *(wtj105@163.com)
  • Supported by:
    Nei Mongol Autonomous Region Science and Technology Plan Project(2020GG0124)

摘要:

绵刺(Potaninia mongolica)是古老的单种属残遗种, 在中国分布于西北荒漠区, 为国家二级重点保护植物。为了揭示不同类型绵刺种群的结构、种内或种间的相互作用以及对环境的适应策略, 该研究选择集中分布区的绵刺种群(阿拉善种群, 在砾石地大面积分布)和分布区东缘的种群(鄂尔多斯种群, 在沙地呈斑块分布), 采用大小结构分析法将绵刺植株分为3个等级(I级: d ≤ 10 cm; II级: 10 cm < d ≤ 30 cm; III级: d > 30 cm, d为株高×冠幅长×冠幅宽的立方根), 运用空间点格局分析的Ripley’s K函数对2个绵刺种群的年龄结构、空间分布格局以及各大小级间空间关联性进行分析。结果表明: 1)阿拉善绵刺种群以II级植株为主, 占69%, I级植株虽仅占5%, 但由于无性生殖的存在, 种群仍呈稳定状态; 而鄂尔多斯种群II级与III级植株占比相近, 无I级植株, 以种子进行更新受限。2)阿拉善种群总体呈随机分布, 其中I、II级植株在中小尺度以聚集分布为主, 在大尺度呈随机分布; 鄂尔多斯种群不论是总体还是各大小级均以聚集分布为主, 与种间竞争有着较大的关系。3)阿拉善种群III级个体与I级个体在中小尺度呈显著负关联, 体现出高龄级植株对幼小植株的抑制作用; 鄂尔多斯种群的II级、III级植株随着尺度范围的增大呈现显著正关联, 表现出成熟龄级间的正相互作用。

关键词: 东阿拉善, 绵刺, 空间分布格局, 空间关联, 大小级结构

Abstract:

Aims Potaninia mongolica, as a remnant species of ancient monospecific genus distributed in the northwest desert area, belongs to the category of national secondary key protected plants in China. The present study aims to investigate the structure, intra- and interspecific relationships, as well as the adaptation strategies to the environment of different types of P. mongolica populations. In particular, the age structure, spatial distribution patterns, and spatial correlations between size classes of P. mongolica populations were analyzed.

Methods Potaninia mongolica population concentrated in the gravel land (referred to as the Alxa population) and distributed in sandy soil in the eastern marginalia of distribution area (referred to as Erdos population) were selected. Through the size structure analysis method, P. mongolica individuals were categorized into three size classes, namely class I: d ≤ 10 cm; class II: 10 cm < d ≤ 30 cm; and class III: d > 30 cm, where d stands for the cubic root of the product of crown length, crown width and plant height. Moreover, the age structure, spatial distribution patterns, and spatial correlations between size classes of the selected P. mongolicapopulations were analyzed using the Ripley’s K-function through spatial point pattern analysis.

Important findings Results of the study include: 1) The Alxa population of P. mongolica was dominated by class II plants, accounting for 69%, whereas class I plants accounting for only 5% of the total population. However, the Alxa population was observed to be stable because of asexual reproduction. On the other hand, for the Erdos population, the proportion of class II and III plants were similar, and no class I plants were observed, which resulted in limited population renewal by seed propagation. 2) The Alxa population was randomly distributed, with class I and II plants predominantly distributed in clusters at small and medium scales and randomly distributed at large scales. Nevertheless, the Erdos population was predominantly distributed in clusters, both in general and at all size scales, which was strongly related to interspecific competition. 3) There was a significant negative correlation between class III and I individuals of the Alxa population at small and medium scales, reflecting the inhibition effect of the senior individuals on the young individuals. However, class II and III plants of the Erdos population showed a positive association with increasing scale range, suggesting a positive interaction between mature age classes of P. mongolica.

Key words: eastern Alxa, Potaininia mongolica, spatial distribution pattern, spatial association, size structure