Biodiversity and functioning of restored wetlands
Title: Co-benefits and possible unintended consequences of restoring wetlands for nutrient reduction
Location: Central Iowa
Time Period: 2023 - 2025
Research Team: Charlie Loewen
Project Description: Agriculture is a leading driver of eutrophication, the enrichment of water with nitrogen (N) and phosphorus (P). Edge-of-field practices such as the construction or restoration of wetlands that intercept and process runoff offer important opportunities to mitigate nutrient losses. However, the differential effects of wetlands on N and P removal influence the ratio of these critical nutrients and the composition of biological communities both within wetlands and in their receiving waters. Wetlands serve a suite of ecosystems services and their importance for supporting biodiversity is well established; however, the biological value of constructed or restored habitats can vary widely and there is much value to be gained if we can learn to design and maintain these wetlands to optimize their ecological functioning.
Objective: We will quantify several biological co-benefits/consequences of edge-of-field nutrient reduction achieved by wetland restoration. Firstly, we will assess the biodiversity of primary producers and their consumers in a series of restored Iowa wetlands to understand their biological and conservation values. Secondly, we will quantify the ecological effects of wetland nutrient reduction on different functional and trophic groups to infer consequences for downstream ecosystem health.
Approach: We will apply a bioindicator approach using surveys of primary producers and invertebrates to evaluate wetland functioning and habitat quality in relation to differences in restoration design, nutrient availability, and other local conditions. By extending surveys immediately upstream and downstream of the wetlands, we will also test how changes in water quality (including shifting nutrient ratios) influence ecological communities and risks of harmful algal blooms.
Publications:
Funders: Iowa Nutrient Research Center
Disclaimer: This is an active research site, please contact Charlie Loewen (cloewen@IASTATE.EDU) prior to planning any site visits.