276-5 Decadal Scale Recruitment, Storage, and Transport of Fluvial Wood in a Small Upland Watershed, Ohio, USA

Session: Natural and Urban Channel Responses to Disturbance, Management, and Restoration

Presenting Author:

Authors:

Abstract:

Large accumulations of wood in rivers—commonly referred to as Large Woody Debris—are a healthy and natural source of geomorphic and biogeochemical complexity, despite the seemingly negative connotation of “debris.” Indeed, our previous work on Raccoon Creek, a 264 km², low-gradient, agricultural, upland watershed, demonstrates a link between logjams and enhanced respiration in streambed ecosystems. A challenge remains, however, generalizing high-resolution, reach-scale biogeochemical observations to the entire watershed. To this end, here we quantify the dynamics of wood recruitment, storage, and transport from the headwaters of Raccoon Creek to its outlet, focusing on the 46 km main stem of the system. We use point cloud data from a 1 m-resolution airborne lidar survey to identify all trees in the riparian buffer that are both tall enough and close enough to the river to potentially become fluvial wood; this population has previously been defined as Potential Large Woody Debris or PLWD. We use aerial photographs from 2015 to 2025 to map all in-channel large wood (LW) along the 46 kilometers of Raccoon Creek. We mapped the wetted width of the river at 100 m stations using the 2023 aerial imagery and quantified sinuosity and average channel gradient within 1 km-reach bins using a 1 m-resolution, lidar-derived digital elevation model. Our results indicate ~7,000 trees available for recruitment into Raccoon Creek with a maximum rate of 272 PLWD/km and a minimum rate of 14 PLWD/km. From year to year, LW accumulations in each 1 km reach ebb and flow, although wood is consistently scarce in the farthest upstream and downstream reaches. This requires that wood is mobile from year to year  in Raccoon Creek and/or new wood is recruited into the river on an annual basis. LW is either exported downstream  to the Licking River system or removed by stakeholders within the Raccoon Creek watershed. There are no correlations between LW/km and PLWD/km, stream gradient, drainage area, or wetted width. There is a weak correlation between sinuosity and LW/km. This lack of any significant relationship between LW occurrences and potential external controls is somewhat surprising, and none of these metrics can be used to anticipate the presence or movement of LW in this system.

Geological Society of America Abstracts with Program. Vol. 57, No. 6, 2025

doi: 10.1130/abs/2025AM-7510

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