School of Forest Sciences, University of Eastern Finland, Yliopistokatu 7, P.O. Box 111, Joensuu, FI-80101, Finland.
Ecol Appl. 2017 Mar;27(2):589-602. doi: 10.1002/eap.1468.
Intensive forest management, together with fire suppression, have decreased structural complexity and altered dynamics of boreal forests profoundly. Such management threatens forest biodiversity and can reduce the provision of ecosystem services. Although the importance of ecosystem services is widely acknowledged, conservation strategies are hindered by poor knowledge about diversity patterns of service provider species as well as on mechanisms affecting these assemblages at different spatial and temporal scales. In this study, we assessed the effect of disturbance management on forest pollinator communities. To do so, we used a large-scale ecological experiment conducted in the year 2000, where forest complexity was manipulated with different harvest regimes and prescribed fire. Results were consistent with a positive response of pollinators to increasing habitat heterogeneity driven by past disturbances. Harvested sites harbored a diverse pollinator community, and showed higher spatial and temporal turnover in species richness. Conversely, old-growth forest communities were a nested subset of harvested sites and contained half of their total diversity. Variation in community composition (β diversity) was primarily affected by species temporal turnover. Throughout the season, β diversity was controlled by fire and harvesting legacies, which provide environmental heterogeneity in the form of flowering and nesting resources over space and time. Conservation strategies may undervalue ecosystem services in dynamic, naturally disturbance-driven, landscapes when relying solely on undisturbed forests areas. However, maintaining natural dynamics in early successional forests, by emulating natural disturbances at harvesting, hold promise for the conservation of both biodiversity and ecosystem services in boreal forests.
集约化森林管理以及抑制火灾,极大地降低了北方森林的结构复杂性并改变了其动态。这种管理方式威胁着森林生物多样性,并可能减少生态系统服务的供应。尽管生态系统服务的重要性得到了广泛认可,但由于对服务提供物种的多样性模式以及影响这些组合在不同时空尺度上的机制缺乏了解,保护策略受到了阻碍。在这项研究中,我们评估了干扰管理对森林传粉者群落的影响。为此,我们使用了 2000 年进行的一项大规模生态实验,其中通过不同的采伐制度和计划火烧来操纵森林复杂性。结果与传粉者对过去干扰驱动的栖息地异质性增加的积极响应一致。采伐区拥有多样化的传粉者群落,并且物种丰富度的空间和时间周转率更高。相反,原始森林群落是采伐区的嵌套子集,包含其总多样性的一半。群落组成的变化(β多样性)主要受物种时间周转率的影响。整个季节,β多样性受到火和采伐遗留物的控制,这些遗留物通过在空间和时间上提供开花和筑巢资源来提供环境异质性。当仅依赖未受干扰的森林区域时,保护策略可能低估了动态、自然干扰驱动景观中的生态系统服务。然而,通过在采伐时模拟自然干扰,在早期演替森林中保持自然动态,为保护北方森林的生物多样性和生态系统服务提供了希望。