Data from: Logging and fire regimes alter plant communities

Disturbances are key drivers of plant community composition, structure and function. Plant functional traits, including life forms and reproductive strategies are critical to the resilience and resistance of plant communities in the event of disturbance. Climate change and increasing anthropogenic disturbance are altering natural disturbance regimes, globally. When these regimes shift beyond the adaptive resilience of plant functional traits, local populations and ecosystem functions can become compromised. We tested the influence of multiple disturbances, of varying intensity and frequency, on the composition and abundance of vascular plant communities and their respective functional traits (life forms and reproductive strategies) in the wet sclerophyll, Mountain Ash Eucalyptus regnans forests of south-eastern Australia. Specifically, we quantified the effect of the type and number of disturbances (including fires, clearcut logging and salvage logging) on plant community composition. We found that clearcut and salvage logging and the number of fires significantly influenced plant community composition and functional traits. Specifically, multiple fires resulted in lower populations of species that depend on on-site seeding for persistence. This includes the common tree species, Eucalyptus regnans, Pomaderris aspera and Acacia dealbata. In contrast, clearcut and salvage logged sites supported abundant on-site seeder species. However, species that depend on resprouting by surviving individuals, such as common and keystone ‘tree ferns’ Dicksonia antarctica and Cyathea australis declined significantly. Our data have important implications for understanding the relationship between altered disturbance regimes and plant communities and the respective effects on ecosystem function. In a period of rapid global environmental change, with disturbances predicted to increase and intensify, it is critical to address the impact of altered disturbance regimes on biodiversity.干扰是调控植物群落组成、结构与功能的核心驱动因子。植物功能性状（plant functional traits），涵盖生活型与繁殖策略，对植物群落遭遇干扰时的恢复力与抵抗力至关重要。当前，全球范围内气候变化与日益加剧的人为干扰正改变着自然干扰制度。当此类干扰制度突破植物功能性状的适应性恢复力阈值时，当地种群与生态系统功能便可能受损。我们以澳大利亚东南部的湿生硬叶林——山灰桉（Eucalyptus regnans）林为研究对象，探究了不同强度与频率的多重干扰对维管植物群落组成、多度及其对应功能性状（生活型与繁殖策略）的影响。具体而言，我们量化了干扰类型与数量（包括火灾、皆伐（clearcut logging）与灾后采伐（salvage logging））对植物群落组成的效应。研究结果表明，皆伐、灾后采伐以及火灾次数显著影响了植物群落组成与功能性状。具体来说，多次火灾会导致依赖原位结种维持种群的物种丰度大幅下降，其中包括常见树种山灰桉（Eucalyptus regnans）、糙叶鼠李（Pomaderris aspera）以及银叶金合欢（Acacia dealbata）。相比之下，皆伐与灾后采伐的样地则孕育了大量原位结种物种。然而，依赖存活个体萌蘖更新的物种，比如作为常见关键种的树蕨——软树蕨（Dicksonia antarctica）与澳大利亚桫椤（Cyathea australis），其种群数量出现了显著降低。本研究数据对于解析干扰制度改变与植物群落之间的关联，及其对生态系统功能的相应影响具有重要意义。在全球环境快速变化、干扰强度与频率预计持续增加的当下，厘清干扰制度改变对生物多样性的影响至关重要。