ORGANIC CARBON-MINERAL-NUTRIENT INTERACTIONS IN WETLAND SOILS NEAR LAKE MICHIGAN

The coast of Lake Michigan provides a unique habitat for living organisms under a changing climate. The shoreline of Lake Michigan hosts a variety of soil ecosystems including beach sediments, sand dunes, interdunal wetlands, and forest soils. The biogeochemical cycles of carbon and nutrients such as phosphorus drive the metabolism in the soil biota, but what are the key environmental/geochemical factors for these biogeochemical processes is not well-known. In this study, we collected soil samples from the shoreline of Lake Michigan spanning over 200 km, and we measured the concentrations and spatial distribution of dissolved organic carbon and nutrients in the samples. We also examined the mineral effects on organic carbon degradation and phosphorous bioavailability, and a strong interaction between organic carbon, minerals, and nutrients was observed. The findings suggest an important role of minerals in controlling organic carbon decomposition and phosphorous cycling in coastal environments, which may provide additional insights into understanding the biogeochemical processes in wetland ecosystems.