不同生态恢复阶段种内竞争影响下的马尾松种群死亡率研究

王晓宁 崔煜婕 张滋隆

摘 要：种内竞争作为长期存在且不断调整的生态关系，是影响种群的死亡率变化不可忽略的因素。为明确种内竞争在生态恢复中对马尾松种群死亡率的影响，在福建省长汀县设立了3处样地，对先锋种马尾松的存活状况进行调查，并使用Hegyi竞争指数量化了种内竞争强度。结果表明：先锋阶段后期，马尾松个体大小分布分散，种内竞争最为激烈，先锋阶段中期与早期，马尾松个体大小变异性低，且早期的种内竞争强度高于中期。伴随种内竞争强度的增加，幼苗的死亡风险提升。种内竞争在生态恢复先锋阶段的早期与中期，显著影响马尾松种群死亡率，而先锋阶段后期，种内竞争不是影响马尾松种群死亡率的主要因素。研究结果表明，种内竞争对马尾松种群的影响具有阶段化的差异，种群内不同大小的个体对于种内竞争的响应不同。

关键词：生态恢复;种内竞争;马尾松;种群死亡率

中图分类号：S 791.248 文献标志码：A 文章编号：0253-2301（2021）01-0026-06

DOI：10.13651/j.cnki.fjnykj.2021.01.005

Abstracts：Intraspecific competition， as a long-standing and constantly adjusted ecological relationship， is an important factor affecting the variation of population mortality. In order to clarify the effect of intraspecific competition on the population mortality of Pinus massoniana during ecological restoration， three sample plots were set up in Changting County of Fujian Province. The survival status of pioneer species of Pinus massoniana was investigated， and the intensity of intraspecific competition was quantified by using Hegyi competition index. The results showed that in the later period of pioneer stage， the individual size distribution of Pinus massoniana was scattered， and the intensity of intraspecific competition was the most intense. In the middle and early periods of pioneer stage， the variability of individual size of Pinus massoniana was low， and the intensity of intraspecific competition in the early stage was higher than that in the middle stage. With the increase of intraspecific competition intensity， the mortality risk of seedling increased. Intraspecific competition significantly affected the population mortality of Pinus massoniana in the early and middle periods of pioneer stage during ecological restoration， but in the later period of pioneer stage， intraspecific competition was not the main factor affecting the population mortality of Pinus massoniana. The research results showed that the effects of intraspecific competition on the population of Pinus massoniana were different in stages， and the individuals of different sizes in the population had different responses to intraspecific competition.

Key words：Ecological restoration; Intraspecific competition; Pinus massoniana; Mortality of the population

種群动态作为种群生态学的核心问题[1-2]，现有研究多从种群的生死过程对其进行讨论。研究证实个体死亡对种群动态产生的影响不可忽视[3]，但在目前的种群动态分析中多从内源性的影响因素对个体的死亡机制进行讨论[4-5]，忽略了外源性因素。作为种群发展过程中长期存在且不断调整的生态关系，竞争来源不仅包括内源性的种内竞争，还包括外源性的种间竞争[6-7]，是影响种群动态变化的不可忽视的因素，但其对个体死亡率的影响机制尚不明确。……