This book focuses on how the ecology and biology of soil organisms is affected by the addition of biochar to soils. It covers direct and indirect effects of biochar addition to soils, on the soil carbon cycle, impact on plant resistance to foliar and soilborne disease, interactions with pathogenic, mycorhizal and saprophytic fungi. The book focuses on application of biochar to remediate polluted soils, taking into account possible toxic effects of biochar on soil fauna. One of the chapters provides extended information on the role of biochar in soil using isotopic tracing techniques.