Cover crops increase crop production, control soil erosion, and are an increasingly common component in Midwestern agricultural practices. In northwest Ohio, cover crops are particularly important because much of the soil is comprised of low nutrient holding clay. To improve crop yields, fertilizers are commonly added, but their link to aquatic algal blooms and other ecological damage has precipitated a need for alternative sources of soil amendments. One potential source of soil amendments stems from material currently dredged from Lake Erie, which produces 1.5 million cubic yards of sediment each year. However, the potential use of dredged sediments for agriculture amendments and its resulting effects on soil microorganism communities, has received little attention. In order to understand how dredge sediment shifts these communities when applied in agricultural settings, we examined changes in dredge sediment fungal communities due to the application of a winter cover crop (winter rye: Lolium perenne) by comparing plots planted with the cover crop and left fallow through the winter. We haphazardly collected ten soil samples from each plot, before and after planting of the cover crop. We recovered fungal DNA using the primers ITS1 and 2, and compared the resulting communities using multivariate statistics.
Results/Conclusions
The presence of the cover crop L. perenne increased the abundance of beneficial fungi compared to the plot left fallow. This shift in the fungal community of dredged sediment mirrors that which is seen when a cover crop is grown in traditional agricultural fields that do not use dredge sediment. This suggests the suitability of dredged sediment for agricultural soil amendment when used in combination with a cover crop. Shifts in the microorganism community are important if dredged material is to be used as agriculture amendments, as establishing beneficial microbiota is vital for successful crop production. This work represents the first to investigate potential agricultural benefits of cover crop usage in conjunction with dredged material and is to the best of our knowledge, the only research to examine the usefulness of dredged material in agricultural practices in Ohio. The use of dredged material as an agricultural amendment in nutrient poor soil is becoming more common worldwide but little is known about the response of the fungal community to these amendments and the role cover crops play in stimulating these organisms. That makes this research particularly important in understanding these dynamics.