Microbiological activity and carbon mineralization in pampean soils with different agricultural use intensity

1 The processes involved in the flows of matter and energy of terrestrial ecosystems depends 2 heavily on soil biological activity, the current conventional agricultural managements could alter 3 the biological mechanisms involved in decomposition and nutrient cycling in agroecosystems. 4 The aim of this study was to compare the activity levels and soil microbial biomass between 5 different agricultural pampean soil uses and its relationship to carbon mineralization. 25 years of 6 agricultural use were compared with 25 years of ecological reserve naturalized where each 7 agroecosystem soil were collected at 61 125 183 236 302 368 431 488 days for 8 measuring their moisture, organic matter, enzymatic activity, microbial biomass carbon, soil 9 respiration, metabolic quotient, microbial quotient and carbon mineralization rate. The distance 10 between agroecosystems is less than 800 m, thus assuming the same soil and climatic conditions. 11 The data were evaluated by Friedman test finding significant differences in moisture, organic 12 matter, enzymatic activity, soil respiration y microbial quotient (p< 0.01). Difference was also 13 found in the microbial mineralization rate of carbon (p< 0.1). 14