Effects of forest management on dead wood supply and implications for biodiversity

森林管理对死木供应的影响及其对生物多样性的影响

• 批准号: 203116-2011
• 负责人: Malcolm, Jay
• 金额: $ 2.77万
• 依托单位: University of Toronto
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2011
• 资助国家: 加拿大
• 起止时间: 2011-01-01 至 2012-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=476946
• 关键词: Effects; forest; management; dead; wood

Woody debris (WD), which includes both downed wood and snags, is thought to be an important resource for many organisms, but one that is especially sensitive to forest management practices. Although the importance of WD for biodiversity is widely recognized, and indeed WD retention guidelines to sustain wildlife habitat and ecological function are ubiquitous in forest management planning, their basis and effectiveness at present is not fully understood. The proposed research will use manipulative field studies and computer-based modelling to address these gaps in boreal northeastern Ontario. Specific objectives will be to: 1) undertake field studies in areas of different levels of downed WD removal to identify key indicator taxa and to better understand habitat supply relationships (with a focus on key groups of saproxylic insects [those dependent upon dead and dying wood], fungi, and small mammal fauna) and 2) parameterize a modelling framework in which short- and long-term effects of particular management practices on WD habitat supply can be investigated. Key hypotheses to be tested include: 1) reductions in the local supply of WD will result in reduced colonization among certain groups of organisms, with net reduction of species richness of WD; 2) small mammal population densities and productivity, movements, and foraging behaviour will vary in response to variation in the quantity and quality of WD; and 3) existing guidelines for WD retention will prove inadequate for long-term, stand-level conservation of biodiversity in the face of new biomass demands. Field work will focus on reference old-growth plots, conventional and biomass clearcuts, and a manipulative experiment in which all, one-half, or no downed WD was removed from 40-65 year-old, 2.25 ha study plots. The research is of particular significance in that it is: 1) precedent setting in that it makes use of a powerful experimental design and novel techniques to provide critical information on biodiversity indicators and WD supply thresholds and 2) will examine the relationship between harvesting practices and long-term WD habitat supply, including in operational-scale biofuel harvests.

木质碎片(WD)，包括倒下的木材和障碍，被认为是许多生物的重要资源，但对森林管理做法特别敏感。尽管WD对生物多样性的重要性得到了广泛的认可，而且在森林管理规划中确实普遍存在维持野生动物栖息地和生态功能的WD保留准则，但其基础和有效性目前还没有得到充分的了解。这项拟议的研究将使用操纵性实地研究和基于计算机的建模来解决安大略省东北部北部地区的这些差距。具体目标将是：1)在不同水平的WD清除区域进行实地研究，以确定关键的指示分类群并更好地了解栖息地供应关系(重点是腐植酸昆虫[那些依赖枯木和垂死的木材]、真菌和小型哺乳动物动物的关键群体)和2)确定一个模型框架，在该框架中可以调查特定管理做法对WD栖息地供应的短期和长期影响。有待检验的关键假设包括：1)当地可再生水供应的减少将导致某些生物群体的定居减少，可再生水的物种丰富度净减少；2)小型哺乳动物的种群密度和生产力、迁移和觅食行为将随着可再生水的数量和质量的变化而变化；以及3)事实证明，面对新的生物质需求，保留可再生水的现有指导方针将不足以长期、标准地保护生物多样性。实地工作将集中在参考老树种地块、常规采伐和生物量砍伐，以及一项操纵实验，在该实验中，从40-65年生的2.25公顷研究地块中移除全部、一半或没有被砍伐的WD。这项研究具有特别重要的意义，因为它是：1)开创先例，因为它利用强大的实验设计和新技术来提供关于生物多样性指标和WD供应阈值的关键信息，以及2)将审查收获做法和WD长期栖息地供应之间的关系，包括在可操作规模的生物燃料收获方面。