Earthworms Contribute to Increased Turnover in Biochar Amended Soils.

With increased interest in bioenergy production from pyrolysis, biochar is likely to become a widely available co-product. Research on using biochar as a source of fertility or to increase carbon sequestration is growing; however, land application of biochar is likely to impact the biotic components of the land-use systems in which it can be applied. We investigated the effect of poultry litter (PL) and pine chip biochar (PC) on earthworm (Eisenia Fetida) survival and reproduction, soil respiration, and soil microbial biomass in two soils common in the southeastern U.S. Poultry litter biochar had a negative effect on earthworm survival at rates higher than 67 Mg biochar ha^-1. Increased soil pH or salt levels may have contributed to decreased earthworm survival. Soil respiration was correlated with earthworm activity. Greater respiration rates were seen in the PC biochar than in the PL biochar amended soils. Our results indicate that different types of biochar may have different effects on soil biota.