Water Resources Research Act Program

Details for Project ID 2009MD199B

Role of Invertebrate Bioturbation in Phosphorus Retention of Agricultural Ditch Soils--Summer Fellowship

Institute: Maryland
Year Established: 2009 Start Date: 2009-03-01 End Date: 2010-02-28
Total Federal Funds: $5,500 Total Non-Federal Funds: $13,750

Principal Investigators: Allen Davis, William Lamp

Project Summary: Agricultural ditches on the Eastern Shore of Maryland contain actively developing soils that create a unique biogeochemical environment where nutrients such as phosphorus may be sequestered or released, thus impacting nutrient pollution of the Chesapeake Bay. In coastal plain soils, phosphorus is expected to be bound primarily to aluminum and iron oxides. This work will demonstrate how burrowing aquatic invertebrates promote the development of iron oxides and hydroxides in the upper layer of ditch soils during the growing season by increasing the flux of oxygen from the water column into the underlying anoxic soil layers, and that this increased persistence of iron oxides and hydroxides increases the phosphorus retention capacity of ditch soils. Information gathered from this study will help in future field studies by demonstrating how ditch soils react to invertebrate bioturbation, and will determine methods by which bioturbation effects can be monitored and quantified in the field.