Using Aerial Photography to Estimate Riparian Zone Impacts in a Rapidly Developing River Corridor

Abstract

Riparian zones are critical for protecting water quality and wildlife, but are often impacted by human activities. Ongoing threats and uncertainty about the effectiveness of buffer regulations emphasize the importance of monitoring riparian buffers through time. We developed a method to rapidly categorize buffer width and landuse attributes using 2007 leaf-on aerial photography and applied it to a 65 km section of the Toccoa River in north Georgia. We repeated our protocol using 1999 leaf-off aerial photographs to assess the utility of our approach for monitoring. Almost half (45%) of the length of the Toccoa River was bordered by buffers less than 50 ft wide in 2007, with agricultural and built-up lands having the smallest buffers. The percentage of river length in each buffer width category changed little between 1999 and 2007, but we did detect a 5% decrease in agricultural land use, a corresponding increase in built-up land use, and an additional 149 buildings within 100 ft of the river. Field verification indicated that our method overestimated buffer widths and forested land use and underestimated built-up land use and the number of buildings within 100 ft of the river. Our methodology can be used to rapidly assess the status of riparian buffers. Including supplemental data (e.g., leaf-off imagery, road layers) will allow detection of the fine-scale impacts underestimated in our study. Our results on the Toccoa River reflect historic impacts, exemptions and variances to regulations, and the ongoing threat of vacation home development. We recommend additional monitoring, improvements in policy, and efforts to increase voluntary protection and restoration of stream buffers.

Using Google Earth Engine to Assess Temporal and Spatial Changes in River Geomorphology and Riparian Vegetation

“…2011; Owers et al. 2012) and few studies have explored multi‐temporal (biannual and monthly) analysis of riparian vegetation extent by incorporating automatic image classification approach.…”

Using occupancy and species distribution models to assess the conservation status and habitat use of the goldline darter (Percina aurolineata) in Georgia, USA

“…Conservation activities on private lands could include conservation easements, reforestation of riparian zones, landowner education on buffer management, cattle exclusion and practices to minimise the impact of new development (Etowah Habitat Conservation Plan Advisory Committee 2007; Owers et al 2012). Some of the headwater streams and mainstem reaches are already protected by public conservation areas (e.g., Rich Mountain Wildlife Management Area), and additional land acquisition would protect remaining forested tracts from development.…”

“…Some of the headwater streams and mainstem reaches are already protected by public conservation areas (e.g., Rich Mountain Wildlife Management Area), and additional land acquisition would protect remaining forested tracts from development. Conservation activities on private lands could include conservation easements, reforestation of riparian zones, landowner education on buffer management, cattle exclusion and practices to minimise the impact of new development (Etowah Habitat Conservation Plan Advisory Committee 2007; Owers et al 2012). The region's water plan outlines alternatives to reservoir construction including water conservation, increased storage within existing reservoirs and reuse of highly treated wastewater (Coosa North Georgia Water Planning Council 2011).…”

Comparison of Image Endmember- and Object-Based Classification of Very-High-Spatial-Resolution Unmanned Aircraft System (UAS) Narrow-Band Images for Mapping Riparian Forests and Other Land Covers

“…Floodplain/riparian forests are also critical for biodiversity, as they provide Land 2022, 11, 246 2 of 33 habitats for a myriad of plants and animal species [4]. They also markedly affect downstream river water quality by minimizing pollution from the surrounding landscape, by enabling increased reduction of nutrients and sediment in higher-biomass areas [5] and by protecting against erosion [6][7][8][9].…”