Microbial attributes and carbon and nitrogen stocks in Latosol under irrigated monocropping and intercropping

Resumo

Monocropping and intercropping maize and pasture irrigated areas in promoting changes in soil biological attributes, however, little is known about these changes in environments ecotone between Cerrado and Caatinga. The aim of the study was to evaluate microbial attributes and carbon and nitrogen stocks in distrophic yellow Latosol soil under monocropping of maize and brachiaria and intercropping of these cultures under two irrigation blades. The study was conducted in the Alvorada do Gurgéia city, Piauí State, Brazil, during the year of 2009, the treatments consisting of three production systems (monocropping of maize and brachiaria and intercropping between maize and brachiaria), under two irrigation blades (L1 = 647.9 e L2 = 564.5 mm) e two soil depths (0-0.10 and 0.10-0.20 m). The variables analyzed were microbial biomass, basal respiration, microbial quotient, metabolic quotient, the contents of total organic carbon, the nitrogen and carbon and nitrogen stocks. Biological attributes of the soil are influenced by monocropping and intercropping of maize and brachiaria, irrigation blades and soil depth. The blades of irrigation, by influencing the water content in the soil, have greater effect on the microbial attributes, may occur individually, as in the case of microbial carbon, or associated production systems of maize and brachiaria under intercropping or monocropping, as detected for of total organic carbon, microbial and metabolic quotient, nitrogen content and carbon and nitrogen stocks.