Microbial dynamics during composting of filter cake reactivated with chicken manure

Spanish; Castilian. Se estudió la dinámica microbiana, así como el contenido de nitrógeno mineral y total durante el proceso de compostaje de cachaza reactivada con gallinaza. Se establecieron cuatro sustratos con diferentes proporciones de cachaza:gallinaza (10:0, 9:1, 7:3 y 5:5 v/v), en contenedores de 68 litros durante 87 días. Las variables evaluadas fueron: temperatura, poblaciones de bacterias, hongos, microorganismos ligninolíticos, evolución de CO2, nitrógeno total, contenido de amonio y nitratos. La adición de gallinaza a la cachaza almacenada, incrementó las poblaciones de bacterias, hongos y microorganismos ligninolíticos, mostrando poblaciones de 9.9, 5.5 y 6.4 unidades logarítmicas (ULog), respectivamente. El sustrato 5:5 v/v presentó disminución en NH+4-N (de 947 a 268 mg∙kg-1), aumento en NO-3-N (de 2.7 a 483 mg∙kg-1) y en nitrógeno total (3.4 a 4.7 %). Esta proporción de gallinaza y cachaza resultó mejor, ya que fue estable biológicamente (compost) y tuvo el mayor contenido de nitrógeno total.

English. Microbial dynamics, mineral and total nitrogen content were studied during the composting process of filter cake reactivated with chicken manure. Four substrates with different proportions of filter cake:chicken manure (10:0, 9:1, 7:3 and 5:5 v/v) were tested using 68 liters containers for 87 days. Temperature, total populations of bacteria, fungi, ligninolytic microorganisms, CO2 evolution, total nitrogen, ammonium and nitrate content were the evaluated variables. The addition of chicken manure to stored filter cake increased the populations of bacteria, fungi and ligninolytic microorganisms, showing microbial populations of 9.9, 5.5 and 6.4 log units (ULog), respectively. Substrate 5:5 v/v showed a decrease in NH+4-N (from 947 to 268 mg∙kg-1) and an increase in NO-3-N (from 2.7 to 483 mg-∙kg¹) and in total nitrogen (3.4 to 4.7 %). This proportion of chicken manure and filter cake was better because it was biologically stable (compost) and had the highest content of total nitrogen.