人工抚育对桉树人工林林下生物多样性的影响

目的]探讨桉树林人工抚育对林下生物多样性的影响,为桉树人工林的科学经营提供参考依据.方法]选择具代表性的典型林分设置调查样地,分别调查灌木层和草本层的植物名称、株数、高度、盖度和密度等指标,通过计算物种的重要值和多样性指数,对比分析人工抚育桉树林对林下植物多样性的影响程度.结果]4年生人工抚育桉树林和未抚育桉树林的灌木植物分别为29和53种,草本植物分别为10和16种.经人工抚育的桉树林灌木个体密度、高度和草本植物个体密度均最小,分别是未抚育桉树林的40.8％、28.8％和11.9％.人工抚育桉树林林下灌木植物分布的均匀性比未抚育桉树林高17.2％,对灌木层和草本层的多样性指数H′、D、J影响不明显.结论]人工抚育导致灌木植物的个体密度、高度和草本植物的个体密度显著降低和物种丰富度降低,造林整地时适度抚育是人工林生物多样性保育和维持的有效措施.

Effects of artificial tending on understory biological diversity in Eucalyptus plantations

Objective]The influence of artificial tending on understory biological diversity was studied in order to pro- vide references for promoting scientific management of Eucalyptus plantations. Method]Typical forest stands were chosen for setting investigation plots to investigate plant name, plant number, height, cover degree and density. By calculating impor- tant value and diversity index, influence level of artificial tending on understory biological diversity in Eucalyptus plantations was analyzed. Result]Four-year-old Eucalyptus plantations on artificial tending and without tending had 29 and 53 shrubs as well as l0 and 16 herbs, respectively. Individual density, height of shrub layer and density of herbaceous layer in Euca- lyptus on artificial tending were the lowest, which were 40.8%, 28.8% and 11.9%, respectively. Evenness index of shrub layer in Eucalyptus plantations on artificial tending was 17.2% higher than plantation without tending, but diversity index H＇, D and J of shrub layer and herb layer of Eucalyptus plantations on artificial tending had no significant difference. Con- clusion]Artificial tending remarkably reduced individual density and height of shrubs as well as individual density and species richness of herbs. Proper artificial tending is an effective method for conserving and maintaining biodiversity in plan- tations.