Abstract

Comparing forest and harvested wood product carbon (C) stocks and accumulation among forest management treatments commonly applied in managed forests is needed to inform planning and policy decisions for C objectives. Therefore, pre- and post-harvest C stocks were quantified and C accumulation was projected over a 31-year period (to ∼2050) among forest management treatments that were applied on a subset (n = 3) of the Maine Adaptive Silviculture Network installations in northern Maine, USA. These installations included mature, second-growth forests composed of northern hardwood and hardwood-dominated mixedwood stands. Before treatments were initiated, average aboveground live tree C stocks ranged from 67.1 to 99.7 Mg ha⁻¹. For the aboveground portions of live trees, dead wood and harvested wood products, the projected average annual net change in C (AAC) was 0.232 ± 1.164 Mg ha⁻¹year⁻¹ (mean ± standard deviation). Models of projected AAC indicated that less biomass removal during harvests and greater representation of tree species with low tolerance of shade were associated with positive AAC values. The results emphasize the importance of leveraging multiple harvesting strategies to achieve C objectives, including consideration of forest reserves and using targeted yet operationally feasible silvicultural treatments that promote forest resilience relative to climate change.

摘要

需要比较森林和采伐的木材产品碳 (C) 储量和积累在管理森林中常用的森林管理处理方法中，以便为 C 目标的规划和政策决策提供信息。 因此，在缅因州适应性造林网络装置的子集 ( n = 3)上应用的森林管理处理中，对收获前和收获后的碳库进行了量化，并预测了 31 年期间（至 2050 年）的碳积累在美国缅因州北部。这些装置包括由北方硬木和以硬木为主的混合木林组成的成熟的二次生长森林。在开始处理之前，平均地上活树 C 库范围为 67.1 至 99.7 Mg ha ^-1. 对于活树、枯木和采伐木制品的地上部分，C (AAC) 的预计年平均净变化为 0.232 ± 1.164 Mg ha ^-1年^-1（平均值 ± 标准差）。预测的 AAC 模型表明，在收获期间较少的生物量去除和具有低耐荫性的树种的更多代表性与正 AAC 值相关。结果强调了利用多种采伐策略来实现 C 目标的重要性，包括考虑森林储备和使用有针对性但可操作的造林处理，以促进森林相对于气候变化的恢复力。