生物多样性 ›› 2019, Vol. 27 ›› Issue (10): 1132-1137.DOI: 10.17520/biods.2019208

• 研究报告:生态系统多样性 • 上一篇    下一篇

食物网关键种的判定及其对稳健性的影响

王凤珍1,唐毅1,2,*()   

  1. 1 辽宁大学生命科学院, 沈阳 110036
    2 辽宁大学统计学与数据科学研究院, 沈阳 110036
  • 收稿日期:2019-07-01 接受日期:2019-09-29 出版日期:2019-10-20 发布日期:2019-10-20
  • 通讯作者: 唐毅
  • 基金资助:
    国家自然科学基金(31870709)

Determination of key species in the food web and their impact on the robustness

Wang Fengzhen1,Tang Yi1,2,*()   

  1. 1 School of Life Sciences, Liaoning University, Shenyang 110036
    2 Institute of Statistics and Data Science, Liaoning University, Shenyang 110036
  • Received:2019-07-01 Accepted:2019-09-29 Online:2019-10-20 Published:2019-10-20
  • Contact: Tang Yi

摘要:

食物网关键种的定量判定方法不仅有助于揭示食物网中的物种关系, 而且有利于对关键物种进行优先保护。本研究以包含49个物种的河流生态系统食物网为对象, 计算网络中表征度性质的指标(点度中心度、中介中心度、紧密中心度), 并根据指标对物种进行聚类, 分析不同类物种影响食物网连接稳健性程度的差异, 探讨不同节点去除方式下节点数量对食物网连接稳健性的影响。结果发现, 聚类将食物网中物种分成三类。I类物种具有相对较高的点度中心度、中介中心度、紧密中心度; II类物种具有相对更低的点度中心度、中介中心度、紧密中心度; III类物种的点度中心度、中介中心度、紧密中心度介于前两者之间。I类物种处于更为重要的地位, 可认为是关键种。本研究为如何判定关键种贡献了新的思路。另外, 升序去除方式下, 连接稳健性呈降低趋势; 降序去除与随机去除方式下, 连接稳健性在持续降低后又有小幅度增加, 这表明去除方式对食物网连接稳健性有影响。三种去除方式下, 食物网连接稳健性发生显著变化对应着几乎相同的去除节点数量, 表明关键种在维持食物网稳健性方面发挥着重要作用。

关键词: 聚类分析, 复杂网络, 生态网络, 节点度, 连接稳健性

Abstract:

Understanding key species and their roles and impacts within communities plays a vital role in protecting key species within communities. Species relationship indicators, i.e., betweenness centrality (BC), closeness centrality (CC), and degree centrality (DC) measured food web connectivity among a community of 49 species. Once indicators were calculated, a clustering analysis analyzed species influences on connectivity robustness among different species classes. In addition to clustering analysis, node removal was tested to measure connectivity robustness under removal modes. Based off of clustering results, species were divided into three food web classes: (1) Class I species have relatively higher BC, CC, and DC values. (2) Class II species have relatively lower BC, CC, and DC values while (3) Class III species are intermediate between Class I and Class II species. In our analyses, it appeared that Class I species are more important for food web processes and are therefore considered key species, contributing to our understanding of how to quantify key food web species. Besides, the connectivity robustness decreased along with the increase in removed nodes under the ascending order removal mode. In the descending order and random removal modes, the connectivity robustness slightly increased after a continuous decrease along with the increase in removed nodes. It indicates that removal modes significantly affect the connectivity robustness. Moreover, under the three removal methods, the significant change in the connectivity robustness corresponds to almost the same number of removed nodes. It suggests key species play an essential role in maintaining the connectivity robustness of the food web.

Key words: cluster analysis, complex network, ecological network, node degree, connectivity robustness