Tropical earthworm biomass and density production
Earthworms, as ecosystem engineers (Jones et al. 1994), are important soil components capable of enhancing plant growth (Lee 1985; Brown et al. 1999; Scheu 2003). Searching their inoculation in managed lands, we cultured three tropical endogeic earthworm species (Balanteodrilus pearsei, Pontoscolex corethrurus and Lavellodrilus bonampakensis) in mesocosms (boxes of 35x28x13 cm) and controlled conditions (27±0.2°C temperature and 33% moisture) with 1.5% Mucuna pruriens var. utilis-enriched soil. The experiment was conducted during 150 days. B. pearsei produced the highest fresh mass (311±7.2 gm-2) as a consequence of the high earthworm density production (1062±28 ind m-2). The highest organic matter content in casts was observed with P. corethrurus and B. pearsei species (5.4±0.12 and 4.2±0.4% respectively), 26-30% higher than the noningested substrate.