Effect of land use changes on soil microbial enzymatic activity and soil microbial community composition on Maryland's Eastern Shore

Abstract We compared microbial enzymatic activity and community composition in small, undisturbed, family cemetery soils and surrounding agricultural fields or suburban lawns to determine the effect of land use changes on soil biology. We collected soil from seven sites in Wicomico County, Maryland monthly for one year. Fluorescein diacetate (FDA) hydrolysis and dehydrogenase activity were significantly greater in the cemetery soils compared to field soils (agricultural and lawn) 63% and 30% of the time, respectively. Much less frequently the field soils had significantly higher microbial activity compared to the cemetery soils (10% of sample pairs for both FDA and dehydrogenase). FDA activity measurements were highest in the spring and lowest in late summer at all seven sites, while no seasonal variation was evident for dehydrogenase activity. Dominant bacterial phyla in the soils were similar between field and cemetery sites with the exception of Gemmatimonadetes having higher relative abundance in fields. Fourteen genera differed in relative abundance between cemeteries and fields, and the relative abundance of these genera correlated with soil pH, organic matter, and phosphorus levels. There was no difference in phylotype richness or diversity between fields and cemetery soils. Based on FDA hydrolysis, microbial activity is greater in cemetery soils, providing evidence to suggest land use changes have altered the biological properties of these soils.