Study of the Interaction of Dissolved Organic Carbon, Available Nutrients, and Clay Content Driving Soil Carbon Storage in the Rice Rotation Cropping System in Northern Thailand

The appropriate management of crop residues in a rice rotation cropping system (RRCS) can promote carbon storage and contribute to soil health. objective this study was determine analyze the amount organic soil, labile dissolved state physicochemical properties their relationship with dynamics under RRCS northern Thailand. be divided into following four categories by pattern: (1) Rice_F (rice (Oryza sativa) followed fallow period); (2) Rice_S shallots (Allium cepa L.); (3) Rice_Mixed tobacco (Nicotiana tabacum), vegetables, or maize (Zea mays)); (4) Rice_P potatoes (Solanum tuberosum)). These patterns classified according (DOC), availability nutrients from fertilization, clay contents. In our study, Rice-F Rice-S led higher (SOC) (DOC) but when Rice-P pattern followed, had lower content, available phosphorus (Avail P), lowest DOC, high contents calcium (Ca2+) magnesium (Mg2+). This also revealed that on basis relationships, Avail P, DOC were most important factors for formation SOC, while Ca2+ Mg2+ subordinate decreased SOC followed. addition, low SOC/clay could reflect saturation, percentages DOC/SOC indicate decomposition SOC.