A Multi-Proxy Environmental Narrative of Oregon White Oak (Quercus garryana) Habitat in the Willamette Valley, Oregon

摘要

Oregon white oak (Quercus garryana) habitat is a priority for conservation in the Pacific Northwest, with process-oriented management considered fundamental for the restoration of these ecosystems. Given that natural and anthropogenic processes operate across a wide spatial and temporal range, an historical perspective provides a more holistic understanding of the complex dynamics of these systems. To this end, we employed a multi-proxy approach to develop an environmental narrative of the Willamette University at Zena Forest (WUZ), Willamette Valley, Oregon between AD 1800 and 2014. We used historic written records, aerial photographs, ecological community characteristics, climate data, and dendrochronological data to investigate forest patterns and processes at the plot, stand, site, and regional scales. Our results illustrate temporal shifts in the importance of factors, including land use and ecological succession, in driving landscape change and forest development at WUZ. Critically, this narrative indicates that modern, patchwork vegetation patterns at WUZ are largely a consequence of anthropogenic practices that became increasingly targeted and intensive over the period of interest. This use of multiple proxy records provides a more comprehensive understanding of the dynamic ecological legacies and human-environment relationship necessary to guide restoration. Setting current management into a broader historical context enhances the efficacy of restoration efforts focused on improving the ecological health and function of oak habitat at WUZ, while contributing to the network of key sites maintaining these priority oak habitats in the Pacific Northwest.