Assessing the Effect of Undirected Forest Restoration and Flooding on the Soil Quality in an Agricultural Floodplain

• Published in: Soil systems Vol. 9; no. 3; p. 88
• Main Authors: Wessinger, Addison, Juarez, Anna, Williams, Clayton J.
• Format: Journal Article
• Language: English
• Published: 07.08.2025
• ISSN: 2571-8789; 2571-8789
• DOI: 10.3390/soilsystems9030088

This study investigated the impacts of land-use history and an episodic flood event on the soil quality of a riverine floodplain ecosystem, providing long-term and short-term disturbance perspectives. The study took place in the Saint Michael’s College Natural Area, which has over a hundred-year history of land-use change. Based on aerial orthoimagery, three zones (a recently abandoned farm field, a new-growth forest, and an old-growth forest) were selected that reflected different land-use histories. Two plots were selected per zone and pooled soil samples were collected from each before and after a major flooding event. Surface soil quality before flooding was often similar among the new- and old-growth forested areas (1.4 mg-P/g-soil, 6.8% soil organic matter (SOM), 0.79 humification index (HIX), and 13% Peak T) but differed from that found in the recently abandoned farm field, which had higher phosphorus levels (1.6 mg-P/g-soil), lower SOM content (3.9%), more microbial-like SOM (0.65 HIX and 17% Peak T), and drier soils. Flooding caused SOM to better resemble that of a forest rather than an agricultural field, and it lowered phosphorus levels. The results of our study suggest that episodic flooding events could help accelerate the restoration of soil organic matter conditions.