BoisJoli_wavelet_data.

Applying a centennial or millennial perspective to disturbance regimes permits an understanding of how these events have varied in the past in relation to climate change. Correctly interpreting this variability is crucial when preparing sustainable forest management practices for future warming. The eastern spruce budworm (Lepidoptera) is the most important biotic disturbance in the eastern Canadian boreal forest. Adult moths are covered by chitinous scales, and lepidopteran scale records in lake sediments have been analyzed to reconstruct Holocene spruce budworm populations. However, the magnitude of these scale accumulations has yet to be calibrated using an independent proxy. Here, we determine whether the impacts of spruce budworm defoliation are recorded by both sedimentary lepidopteran scale accumulations and tree-ring widths. Agreement between proxies was found at five of nine sites and strongest between the proportion of affected trees and scale accumulations while agreement in signal synchronicity was found at six of nine sites and strongest when comparing scale accumulations to a growth suppression index. A species-based composite chronology relying on white spruce produced the clearest outbreak record for both proxy records. Peak scale accumulations correlated well with smaller tree-ring widths, demonstrating that larger scale accumulations correspond to more severe defoliation events. Therefore, lepidopteran scales provide reliable records of spruce budworm abundance serving as a proxy record ameliorating our understanding of how budworm impacts have fluctuated at centennial and millennial time scales in the context of past climate change.以百年至千年尺度的视角审视森林干扰制度，有助于理解此类扰动事件在过去如何随气候变化发生演变。在制定应对未来气候变暖的可持续森林管理措施时，准确解读这种扰动变异性至关重要。东部云杉芽卷蛾（鳞翅目）是加拿大东部北方森林中最重要的生物干扰因子。其成虫体表覆有几丁质鳞片，学界已通过分析湖泊沉积物中的鳞翅目鳞片记录，重建了全新世时期东部云杉芽卷蛾的种群动态。然而，目前仍缺乏独立代用指标对这类鳞片堆积量进行校准。本研究旨在验证：湖泊沉积物中的鳞翅目鳞片堆积量与树木年轮宽度，是否均能记录东部云杉芽卷蛾的落叶为害效应。在9个研究样地中，有5个样地的两类代用指标呈现出显著相关性，其中受为害林木占比与鳞片堆积量的相关性最强；同时，9个样地中有6个样地的代用指标信号同步性良好，且将鳞片堆积量与树木生长抑制指数进行对比时，同步性表现最优。基于白云杉构建的物种复合年表，可为两类代用指标提供最为清晰的虫害暴发序列。鳞片堆积量峰值与较窄的年轮宽度呈现显著负相关，这表明鳞片堆积量越高，对应的落叶为害程度越严重。综上，鳞翅目鳞片可作为可靠的东部云杉芽卷蛾种群丰度代用指标，有助于深化我们对过去气候变化背景下，芽卷蛾为害效应在百年至千年尺度上波动规律的认知。