Soil was sampled using improved soil sampler developed by Jia(1995), Soil was ground and sieved after drying, Carbon was analyzed N/C Analyzer.
土壌はJia(1995)の改良土壌サンプラーで採取、土壌は乾燥後粉砕しふるいにかけた、分析はC/Nコーダーによった。