Understanding long-lasting effects of different silvicultural systems on soil properties is critical to sustainable forest management. We determined even-aged (EA, clearcuts) and uneven-aged (UA, partial harvests; 30% by single-tree selection) management effects on soil properties 5, 15 and 30 years after harvesting, relative to unmanaged old-growth forests, in a hardwood forest in southern Quebec, Canada. In total, 198 plots were sampled in 66 randomly selected sites. We measured coarse woody debris (CWD) and examined key soil physico-chemical properties in the forest floor and mineral horizon (0–20 cm). CWD volume strongly decreased in the forest floor of EA managed forests compared to unmanaged forests; no recovery pattern was observed 30 years post-harvest. Following UA management, CWD volume only significantly decreased 5 years after harvesting. Relative to old-growth forests, sites that were subject to forest harvesting were characterized by soils with lower values for key chemical properties that drive soil fertility, including pH, available K, Ca and Mg, and base saturation. Five years after harvesting, both EA and UA managed forests had higher rates of nitrification than unmanaged forests. Overall, EA management had stronger and longer lasting harvest effects on soil chemical properties than forest sites involving UA management. We also assessed, in a greenhouse pot experiment, whether a hypothetical gradient of decreasing soil fertility would affect seedling growth of three tree species (trembling aspen, white birch, yellow birch). Soil originating from EA managed forests with lower soil fertility resulted in lower height growth rates and total dry biomass for the three species, relative to soil from the unmanaged forest (higher soil fertility). Forest harvesting can have major detrimental effects on soil fertility and productivity, over both the short- and long-term, and impacts may increase with harvest intensity.

了解不同造林系统对土壤特性的长期影响对于可持续森林管理至关重要。我们确定了采伐后 5、15 和 30 年，相对于未管理的原始森林，均龄（EA，砍伐）和不均龄（UA，部分采伐；30% 通过单树选择）管理对土壤特性的影响，在加拿大魁北克省南部的硬木森林中。总共在 66 个随机选择的地点抽取了 198 个样地。我们测量了粗木屑 (CWD) 并检查了森林地面和矿物层 (0-20 厘米) 的关键土壤理化特性。与未管理的森林相比，EA 管理的森林的林地中的 CWD 量大大减少；收获后 30 年未观察到恢复模式。在UA管理之后，CWD 体积仅在收获后 5 年显着下降。相对于原始森林，森林采伐地点的特征是土壤的关键化学特性值较低，这些特性值驱动土壤肥力，包括 pH 值、有效钾、钙和镁，以及碱饱和度。采伐五年后，EA 和 UA 管理的森林比未管理的森林具有更高的硝化率。总体而言，与涉及 UA 管理的林地相比，EA 管理对土壤化学性质的收获影响更大、更持久。我们还在温室盆栽试验中评估了土壤肥力下降的假设梯度是否会影响三种树种（颤杨、白桦、黄桦）的幼苗生长。相对于来自未管理森林的土壤（较高的土壤肥力），源自 EA 管理的森林土壤肥力较低的土壤导致这三个物种的高度增长率和总干生物量较低。森林采伐可能对土壤肥力和生产力产生短期和长期的重大不利影响，而且影响可能随着采伐强度的增加而增加。