Emulating natural disturbance in forest management enhances pollination services for dominant Vaccinium shrubs in boreal pine-dominated forests

Abstract

Lack of natural disturbances and the homogenization of boreal forest because of intensive forest management pose a threat to biodiversity and can endanger the provision of ecosystem services. In this study, we assessed how two methods aimed to promote biodiversity, i.e. prescribed fire and retention forestry (RET), affect ecosystem services supported by bilberry and lingonberry in Scots pine-dominated boreal forests. Shrub cover, flowering, berry yield and percent fruit set of both shrubs were measured and bees were sampled by pan-traps on 24 study sites 13years following a large-scale experiment, where RET (0, 10, 50m3/ha and uncut forests) and fire (yes/no) were manipulated following a replicated factorial design. In general, bilberry performance and reproduction were higher at uncut sites, while lingonberry flowering was positively affected by fire and retention. Bee community composition was mainly determined by percentage of bare ground and number of logs within sites, both nesting resources largely determined by fire and retention. Burnt sites with retention trees serve as pollinator source habitats and contain floral resources, highlighting the importance of natural disturbances and biological legacies in the conservation of pollination services from boreal forests.