Spatial and temporal patterns of nitrification rates in forested floodplain wetland soils of upper mississippi river pool 8

Overbank flooding is thought to be a critical process controlling nitrogen retention and cycling. Yet, studies aimed at quantifying these effects, specifically nitrification, are relatively few. In this study, we investigated the effects of season and flood frequency on soil nitrification rates in forested floodplains of Upper Mississippi River, Pool 8. Samples were collected from three plots within each site in April, August and November 2006. Plots were equally divided among three flood frequency categories as follows: rare, moderate and frequent based on elevation and flood probability model. We found a significant difference in nitrification rates among flood frequency categories as follows: rare > moderate > frequent (F = 4.49, p summer > autumn (F = 8.88, p