Data from: Trade-offs in berry production and biodiversity under prescribed burning and retention regimes in Boreal forests

1. Green tree retention and prescribed burning are practices used to mitigate negative effects of forestry. Beside their effects on biodiversity, these practices should also promote non-timber forest products (NTFPs). We assessed: (1) how prescribed burning and tree retention influence NTFPs by examining production of bilberry Vaccinium myrtillus and cowberry; Vaccinium vitis-idaea (2) if there are synergies or trade-offs in the delivery of these NTFPs in relation to delivery of species richness, focusing on five groups of forest dwelling species. 2. We used a long-term experiment located in eastern Finland with three different harvesting treatments: clearcut-logging, logging with retention patches and unlogged, which were combined with or without prescribed burning. Eleven years after the treatment application, we scored plant cover and berry production in different microhabitats within these treatments, while species richness data for five species groups (ground-layer lichens and bryophytes, vascular plants, saproxylic beetles, pollinators – here bees and hoverflies) were collected at the stand level. 3. Logging favoured cowberry production, particularly for plants growing in the vicinity of stumps. Logging was detrimental for cover and berry production of bilberry. Retention mitigated these negative effects slightly, but cover and berry production were still substantially lower compared to unlogged forests. Prescribed burning increased cowberry production in retention patches and in unlogged forest. Bilberry production decreased with burning, except in unlogged forest where the effect was neutral. 4. No single management treatment simultaneously favoured all values - NTFPs and richness - and trade-offs among values were common. Only bilberry production and beetle diversity were higher under retention forestry, or in unlogged stands, compared to logged stands. Prescribed burning favoured many values when performed in combination with retention forestry, or in unlogged stands, but different treatment combinations favoured different species groups. 5. Synthesis and applications. Our results demonstrate that widely-applied conservation practices in managed forests are unlikely to benefit all ecosystem values everywhere. If high multi-functionality is desired, managing at a landscape scale, countering the local trade-offs among values, may be more appropriate than the stand scale conservation practices commonly practiced today.1. 保留木留存与计划火烧是用于减轻林业经营负面影响的营林措施。除对生物多样性产生影响外，此类措施还应推动非木材林产品（NTFPs）的生产。本研究评估了两项内容：(1) 通过探究欧洲越橘（Vaccinium myrtillus）与红豆越橘（Vaccinium vitis-idaea）的结实量，分析计划火烧与保留木留存对非木材林产品的影响；(2) 聚焦5类森林栖息物种，探究这些非木材林产品的供给与物种丰富度供给之间是否存在协同效应或权衡关系。2. 本研究采用位于芬兰东部的长期定位试验，该试验设置3种采伐处理：皆伐、带保留斑块的采伐以及未采伐林，并分别搭配计划火烧与不实施计划火烧两种措施。在试验处理开展11年后，我们对各处理下不同微生境的植物盖度与浆果结实量进行了调查；同时在林分尺度上收集了5个物种类群的物种丰富度数据，包括地被层地衣与苔藓、维管植物、食朽甲虫以及传粉昆虫（此处指蜂类与食蚜蝇）。3. 采伐措施有利于红豆越橘的结实，尤其是树桩附近生长的植株。但采伐会对欧洲越橘的植物盖度与浆果结实量产生负面影响。保留木留存可小幅缓解这一负面影响，但与未采伐林相比，欧洲越橘的盖度与结实量仍显著偏低。计划火烧可提升保留斑块与未采伐林中红豆越橘的结实量。火烧会降低欧洲越橘的结实量，但未采伐林不受火烧影响，其结实量无显著变化。4. 不存在任何一种营林措施可同时兼顾所有生态系统价值——即非木材林产品供给与物种丰富度——且不同价值间的权衡关系普遍存在。与皆伐林相比，仅保留木营林或未采伐林的欧洲越橘结实量与食朽甲虫多样性更高。当计划火烧与保留木营林结合，或应用于未采伐林时，可提升多项生态系统价值，但不同处理组合对不同物种类群的利好效应存在差异。5. 结论与应用。本研究结果表明，当前人工林经营中广泛应用的保护措施，难以在所有区域兼顾所有生态系统价值。若需实现高度的生态系统多功能性，通过景观尺度的经营来抵消局部的价值权衡，或许比当前普遍采用的林分尺度保护措施更为适宜。