Effects of part and whole straw returning on soil carbon sequestration in C3–C4 rotation cropland

• DOI: 10.1002/jpln.201800573
• Publication Date: 2019-03-25T19:50:39Z
• Authors: Zhen Liu; Tianping Gao; Wentao Liu; Kai Sun; Yanni Xin; Hongjian Liu; Shengzhao Wang; Geng Li; Huifang Han; Zengjia Li,; Tangyuan Ning
• Keywords: Soil carbon; Soil horizon; Crop Residue; Crop Rotation; Conventional tillage

Abstract Long‐term no‐tillage management and crop residue amendments to soil were identified as an effective measure increase organic carbon (SOC). The SOC content, stock (SOCs), sequestration rate (CSR), pool index (CPMI) measured. A stable isotopic approach was used evaluate the contributions of wheat maize residues at a long‐term experimental site. We hypothesized that under conditions, straw retention quantity would affect differently in surface deep soil, contribution C3 C4 crops be different. This study involved four returning treatments, which included no (NT‐0), 0.5 m (from surface) (NT‐0.5), 1 (NT‐1), whole (NT‐W). results showed 0–20 cm layer, SOCs, CSR CPMI NT‐W highest after 14 years management, there obvious differences among treatments. However, SOC, NT‐0.5 lowest 20–100 cm, respectively. value δ 13 C obviously vertical variability ranged from –22.01‰ (NT‐1) layer –18.27‰ (NT‐0.5) 60–80 with enriched (NT‐0.5 NT‐1) 80–100 (NT‐0 NT‐W) layers. maize‐derived NT‐0.5, NT‐1 increased by 11.4, 29.5 56.3% 10.7, 15.1 40.1%, relative those NT‐0 treatment In conclusion, apparent difference total between NT‐1, treatments 0–100 layer. wheat‐derived higher than SOC.