不同经营措施对桉树人工林植物多样性的影响

Effects of Different Management Measures on Plant Diversity in Eucalyptus Plantations

关键词:  桉树人工林  经营管理  植物多样性  干扰

Key words:  Eucalyptus plantations  management measures  plant diversity  disturbance

摘要:

[目的]探讨不同经营措施对桉树(Eucalyptus)人工林植物多样性的影响,为桉树人工林的科学经营提供理论依据。[方法]通过4种不同经营措施试验(即,处理A:人工清理林地、人工除草抚育、施基肥;处理B:火烧清理林地、化学除草抚育、施基肥和追肥;处理C:人工清理林地、人工除草抚育、施基肥和追肥;对照(CK):桉树采伐迹地形成的灌草坡),比较研究不同经营措施对桉树人工林下植物多样性的影响。[结果]除处理B外,其它处理林地的木本植物丰富度及其优势物种组成和多样性指数与造林前相比没有发生明显的变化(P>0.05),其草本植物的优势物种组成和多样性指数也没有发生明显的变化(P>0.05),但种类丰富度则呈逐年下降趋势;处理B的木本植物香农威纳(Shannon-Wiener)指数(H')和均匀度指数(Jsw)显著低于处理A、C和CK,而生态优势度指数(C)则相反(P<0.05);处理A、C的草本香农威纳指数(H')和均匀度指数(Jsw)显著高于CK和B处理,而生态优势度指数(C)则显著低于CK和B处理(P<0.05),A与C处理之间和B与CK之间均无显著差异(P>0.05)。[结论]人工清理林地、人工除草抚育、施基肥对植物多样性的影响较小,而火烧清理林地、化学除草抚育和频繁施肥等经营活动将显著降低桉树人工林下的植物多样性。

Abstract:

[Objective] Investigating the effects of management measures on plant diversity in Eucalyptus plantations could provide theoretical basis for the scientific management of the Eucalyptus plantations.[Methods] A total of 4 treatments (A:Manual ground clearance and weeding, base fertilizing;B:Burning, chemical weeding, base fertilizing and topdressing;C:Manual ground clearance and weeding, base fertilizing and topdressing;CK:Eucalyptus plantations cutover land dominated by shrub and herbaceous) were used to comparatively study the effects of management measures on plant diversity in Eucalyptus plantations.[Results] Except for treatment B, the woody plant richness, dominant species composition and diversity index and herbaceous plant dominant species composition and diversity index did not significantly change (P>0.05) compared with that of before afforestation, while herbaceous plant richness deceased year by year. The woody plant Shannon-Wiener index (H') and Evenness index (Jsw) of treatment B were significantly lower than those of treatment A, C and CK, while ecological dominance index (C) was significantly higher than that of treatment A, C and CK (P<0.05).The herbaceous plant Shannon-Wiener index (H') and Evenness index (Jsw) of treatment A and C were significantly higher than those of treatment B and CK, while ecological dominance index (C) was significantly lower than that of treatment B and CK (P<0.05).There were not significant differences between treatment A and C and B and CK (P>0.05).[Conclusion] Manual ground clearance, weeding and base fertilizing had less influence on plant biodiversity. While burning, chemical weeding and frequently fertilizing would significantly decrease plant biodiversity in Eucalyptus plantations.