Using Fire as a Management Practice in Grassland and Cropping Systems: Effects on Soil Nutrient Availability, Carbon and Nitrogen Contents, and Structure.

Extensive research has been conducted on the effects of fire on forested ecosystems, however little is known about crops and corresponding effects in grassland and cropping systems.  Of the existing research on fire in grasslands, focus has been on alterations of total organic matter, nitrogen content, and soil moisture.  No consensus exists regarding the effects of fire on nutrient availability in grassland systems, as burning frequency produced varying results.  Changes in organic matter include several aspects such as carbon content and chemical forms which can affect lability and the ability of soil to maintain/return to pre-fire conditions.  Soil organic matter (SOM) directly affects the structure, cation exchange capacity (CEC), nutrient availability, pH buffering, and moisture potential of the soil profile and is highly susceptible to disturbances such as burning.  This experiment will attempt to examine short-term effects of fire on grassland and cropping systems and long-term effects on grassland systems.  Short-term effects will be determined by comparison of samples taken prior to and immediately following a burn event.  Long-term effects will be examined based on current soil conditions at sites in which fire is either currently or has been used as a management practice.