探讨松材线虫病疫木采伐后自然恢复的马尾松林树种多样性与生态位特征,可为卫生伐后马尾松林分的经营管理提供参考。以未遭受松材线虫病危害的马尾松林为对照(CK),分别选设中度采伐恢复5 a(MT₅)、中度采伐恢复15 a(MT₁₅)、重度采伐恢复5 a(HT₅)和重度采伐恢复15 a(HT₁₅)的林分,探究不同采伐强度和自然恢复年限对马尾松林树种组成、生态位宽度、生态位重叠和多样性的影响。结果表明:1)与CK相比,疫木采伐后林分中的马尾松重要值、生态位宽度,以及马尾松与其他树种的生态位重叠均值总体下降;2)相同自然恢复年限下,马尾松的重要值、生态位宽度,以及马尾松与其他树种的生态位重叠均值随采伐强度的增大而降低,阔叶树重要值随采伐强度的增大而增大;3)相同采伐强度下,马尾松的重要值、生态位宽度和马尾松与其他树种的生态位重叠均值随自然恢复年限的增加而降低,阔叶树重要值随自然恢复年限的增加而增大;4)自然恢复15 a时,重度采伐后的马尾松次生林物种丰富度显著高于中度采伐的(P<0.05),而自然恢复5 a时差异不显著(P>0.05);5)相同采伐强度下,自然恢复15 a的马尾松次生林物种丰富度、Shannon-Wiener指数和Simpson指数显著高于自然恢复5 a的(P<0.05)。疫木采伐后自然恢复时间越长,马尾松重要值和生态位宽度越低,阔叶树重要值越高,马尾松与其他树种的生态位重叠越少,树种多样性越高,重度采伐相较于中度采伐更能加快这种演变。

This study investigates the biodiversity and niche dynamics in Pinus massoniana forests(PMF)following thinning of trees affected by pine wilt disease to facilitate natural restoration,we aim to provide a scientific basis for the management of PMF stands after sanitation cutting.Employing a PMF stand unaffected by pine wilt disease as the control(CK),the forest stands with moderate cutting and restoration for 5 years(MT₅),moderate cutting and restoration for 15 years(MT₁₅),heavy cutting and restoration for 5 years(HT₅),and heavy cutting and restoration for 15 years(HT₁₅)were selected respectively assess how varying degrees of thinning and periods of natural restoration influence species composition,niche width,niche overlap,and biodiversity of PMF.1)Compared with CK,the important value of P.massoniana,niche width,and the average niche overlap between P.massoniana and other tree species in the forest stands after the cutting of epidemic wood generally decreased.2)Under the same natural restoration duration,the average important value of P.massoniana,niche width,and the average niche overlap between P.massoniana and other tree species decreased with increasing cutting intensity,and the important value of broad-leaved trees increased with increasing cutting intensity.3)Under the same cutting intensity,the average important value of P.massoniana,niche width,and the average niche overlap between P.massoniana and other tree species decreased with increasing natural restoration years,and the important value of broad-leaved trees increased with increasing natural restoration years.4)When the natural restoration lasted for 15 years,the species richness of the secondary forest of P.massoniana after heavy cutting was significantly higher than that after moderate cutting(P<0.05),while the difference was not significant when the natural restoration lasted for 5 years(P>0.05).5)Under the same cutting intensity,the species richness,Shannon-Wiener index,and Simpson index of the secondary forest of P.massoniana with natural restoration for 15 years were significantly higher than those with natural restoration for 5 years(P<0.05).Following thinning of P.massoniana,extended periods of natural restoration correlate with reduced significance and niche breadth of P.massoniana,alongside an increase in the significance of broad-leaved species.Additionally,the niche overlap between P.massoniana and other tree species decreases,resulting in higher species diversity.Intense thinning accelerates these ecological transitions more effectively than moderate thinning.