Methane oxidation in temperate soils: Effects of land use and the chemical form of nitrogen fertilizer

Results are presented from long-term experimental sites showing that land use and agricultural management practices play an important role in mediating the sink strength of aerobic soils for methane. At sites located within 1 km2 at Rothamsted Experimental Station, U.K. the methane sink strength of soil follows the order woodland > grassland > arable. Comparison of grassland plots receiving nitrate-N fertilizer compared to ammonium-N fertilizer shows that the long-term (138 years) application of ammonium-N fertilizer caused a significant decrease in the soil sink strength for methane but that the application of nitrate-N for the same length of time did not.These results are discussed in relation to land use and microbial ecology.