1. Department of Soil Science of Temperate Ecosystems; University of Göttingen; 37077 Göttingen Germany
2. Korea Biochar Research Center and Department of Biological Environment; Kangwon National University; Chuncheon 200-701 Korea
3. Institute of Physico-chemical and Biological Problems in Soil Science; Russian Academy of Sciences; 142290 Pushchino Russia
4. Department of Agropedology; University of Göttingen; 37077 Göttingen Germany