The impact of human activities on sediment yield is poorly constrained in the northeastern United States, as in other northern hemisphere forested landscapes previously occupied by Pleistocene ice sheets. This study examines changes in sedimentation in Little Kennebago Lake (LKL), Maine, in relation to extreme hydrologic events and land-use change. Historical records indicate minimal disturbance before the onset of commercial logging after 1891. Sediment cores record >1,200 years of sedimentation and allow comparison of prehistoric and anthropogenic conditions. Variations in sediment yield are evaluated in the context of hydrologic records and reconstructions of road density and timber harvest derived from historical topographic maps and aerial photographs. Cores collected before and after a highly erosive, localized extreme rainfall event in July 2018 provide a template for interpreting clastic layers found earlier in the record. The frequency of these events increased around 1900, with five layers in the previous ∼1100 years and 12 layers from 1900-2018. This timing corresponds to an increase in suspended sediment yield from 2.0 Mg/km²/yr to 6.4 Mg/km²/yr and increased abundance of pollen taxa associated with forest disturbance. A relative lack of discrete erosion events since ∼1970, in spite of increasing timber harvest, suggests that modern best management practices may be effective in reducing erosion. The 2018 event is a reminder, however, that ongoing reevaluation of management practices is necessary in light of changing hydrology, in this region and elsewhere.

人类活动对沉积物产量的影响在美国东北部受到的约束很有限，就像以前由更新世冰盖所占据的其他北半球森林景观一样。这项研究调查了缅因州小肯纳巴哥湖（LKL）的沉积变化，这些变化与极端水文事件和土地利用变化有关。历史记录表明，在1891年以后开始商业采伐之前，干扰很小。沉积物芯记录了1200年以上的沉积，并可以比较史前和人为条件。在水文记录的背景下评估沉积物产量的变化，并根据历史地形图和航拍照片重建道路密度和木材采伐。在高度侵蚀之前和之后收集的岩心，2018年7月的局部极端降雨事件提供了解释记录早些时候发现的碎屑层的模板。这些事件的发生频率在1900年左右有所增加，在前约1100年中有5层，从1900-2018年有12层。此时间对应于悬浮泥沙产量从2.0 Mg / km的增加² /年至6.4 Mg / km ² /年，并且与森林干扰相关的花粉类群数量增加。尽管木材采伐量增加，但自1970年以来相对缺乏离散的侵蚀事件，这表明现代最佳管理方法可能对减少侵蚀有效。然而，2018年的活动提醒人们，鉴于该地区和其他地方水文学的不断变化，有必要对管理实践进行不断的重新评估。