Data from: Climate suitable planting as a strategy for maintaining forest productivity and functional diversity

Within the timeframe of the longevity of tree species, climate change will change faster than the ability of natural tree migration. Migration lags may result in reduced productivity and reduced diversity in forests under current management and climate change. We evaluated the efficacy of planting climate suitable tree species (CSP) - those tree species with current or historic distributions immediately south of a focal landscape - to maintain or increase aboveground biomass, productivity, and species and functional diversity. We modeled forest change with the LANDIS-II forest simulation model for 100 years (2000-2100) at a 2-ha cell resolution ans 5-yr time steps within two landscapes in the Great Lakes region (northeastern Minnesota and northern lower Michigan). We compared current climate to low and high emission futures. We simulated a low emission climate future with the Intergovernmental Panel on Climate Change (IPCC) 2007 B1 emission scenario and the Parallel Climate Model Global Circulation Model (GCM). We simulated a high emission climate future with the IPCC A1FI emission scenario and the Geophysical Fluid Dynamics Laboratory (GFDL) GCM. We compared current forest management practices (business-as-usual) to CSP management. In the CSP scenario, we simulated a target planting of 5.28 and 4.97 percent of forested area per five year time step in the Minnesota and Michigan landscapes, respectively. We found that simulated CSP species successfully established in both landscapes under all climate scenarios. The presence of CSP species generally increased simulated aboveground biomass. Species diversity increased due to CSP; however the effect on functional diversity was variable. As the planted species were functionally similar to many native species, CSP did not result in a consistent increase nor decrease in functional diversity. These results provide an assessment of the potential efficacy and limitations of CSP management. These results have management implications for sites where diversity and productivity is expected to decline. Future efforts to restore a specific species or forest type may not be possible, however CSP may sustain a more general ecosystem service (e.g., AGB).

在树木物种的存续周期内，气候变化的速率将超过树木自然迁移的能力上限。迁移滞后可能在当前森林经营模式与气候变化的双重影响下，造成森林生产力降低与物种多样性衰减。本研究评估了种植气候适宜树种（Climate Suitable Tree Species, CSP）——即分布于研究样地紧邻南侧的现有或历史分布树种——对维持或提升地上生物量、生产力、物种多样性与功能多样性的有效性。我们借助LANDIS-II森林模拟模型，以2公顷的栅格分辨率与5年为时间步长，对五大湖地区两处研究样地（明尼苏达州东北部与密歇根州下北部）的森林变化进行了为期100年（2000-2100年）的模拟。我们将当前气候情景与低、高排放未来情景进行了对比：采用政府间气候变化专门委员会（Intergovernmental Panel on Climate Change, IPCC）2007年发布的B1排放情景搭配平行气候模式全球环流模型（Global Circulation Model, GCM），模拟低排放气候未来情景；采用IPCC A1FI排放情景与地球物理流体动力学实验室（Geophysical Fluid Dynamics Laboratory, GFDL）的GCM，模拟高排放气候未来情景。我们将现行森林经营模式（照常经营）与CSP经营模式进行对比。在CSP情景中，我们分别模拟了明尼苏达州与密歇根州研究样地每5年时间步内，对应5.28%与4.97%林地面积的目标种植量。研究发现，在所有气候情景下，模拟种植的CSP均能在两处研究样地成功定植。CSP的存在整体提升了模拟得到的地上生物量；物种多样性因CSP种植得到提升，但对功能多样性的影响则存在差异。由于所种植树种的功能性状与多数本土树种相似，CSP经营并未对功能多样性造成显著的单向增减效应。本研究结果评估了CSP经营模式的潜在有效性与局限性，可为预计将出现多样性与生产力下降的林地提供经营参考。未来若无法开展特定物种或森林类型的修复工作，CSP经营或可维持更具普适性的生态系统服务功能（如地上生物量）。