Southeastern Geographer

The cover photo of this issue presents riparian trees, black willows (Salix nigra) established on the point bar of river mile (RM) 74 of the Apalachicola River in Florida. The Apalachicola River is part of the Apalachicola-Chattahoochee-Flint (ACF) system, beginning near the state boundary of Georgia and Florida. The river meanders with a single mainstem at low flow, connecting to the backswamp through sloughs during flood events (Chen et al. 2020). The point bars were much smaller prior to dredging and disposal associated with a navigation project that began in the 1950s (Mossa et al. 2017). As part of this project to create and maintain a navigable channel, the U.S. Army Corps built the Jim Woodruff Dam and conducted dredging and disposing to build a 2.7-m deep, 30.5-m wide channel from Apalachicola, Florida to Columbus, Georgia. Waterway traffic declined starting in the 1980s and the amounts of barge traffic were minimal (Mossa and Chen 2021). In the early 2000s, most of the project's impacts including dredging and disposing ended (U.S. Senate Committee on the Environment and Public Works 2002).

The combination of dam construction and four decades of heavy dredging and disposing have had multiple long-term environmental impacts. The direct impacts to the river include water-level decline, channel bed degradation, channel widening, and enlargement of point bars (Light et al. 2006, Price et al. 2006, Mossa et al. 2017). Comparing aerial photos taken in 1941 and 2004, point bar surface has increased to 263 percent (~ 28 ha) of the area at the 20th percentile water level (Mossa et al. 2017). The point bar enlargement is strongly associated with the disposal of dredging materials (Figure 1), as ~65 percent of the river bank was designated as disposal sites (Mossa et al. 2017), and point bars were targeted for disposing according to the Navigation Maintenance Plan (U.S. Army Corps of Engineers Mobile District 1986). The point bar shown in the cover photo is one of the three largest disposal sites (site 107A, Figure 1) near Blountstown, Florida.

Since dredging was curtailed in the early 2000s, the Apalachicola River is under passive recovery status that allows pioneer riparian vegetation to establish on the bars. Studies of changes in land cover (e.g., water, sand bars, and vegetation) of the mid-Apalachicola River Corridor during the decade following dredging's curtail found that [End Page 85]

the point bar area has shrunk ~15–18 percent due to the growth of riparian vegetation (Mossa et al. 2020, Mossa and Chen 2022). As part of the recovery process, riparian vegetation stabilizes banks and bars and increases biodiversity. Pioneer vegetation starts the vegetation succession that changes the bare surface to floodplain forest. Once the new growth is established, it starts trapping sediments and organic matter (Figure 2A) and increasing the relative elevation that reduces flow velocity and shelters new growth (Figure 2B). Behind the well-established pioneer trees, various plant species join the [End Page 86]