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 l and use and agricultural management practices play an important role i n mediating the sink strength of aerobic soils for methane. At sites l ocated within 1 km (2) at Rothamsted Experimental Station, U.K. the me thane sink strength of soil follows the order woodland > grassland > a rable. Comparison of grassland plots receiving nitrate-N fertilizer co mpared to ammonium-N fertilizer shows that the long-term (138 years) a pplication of ammonium-N fertilizer caused a significant decrease in t he 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.