Integrative effects of no-tillage and straw returning on soil organic carbón and water stable aggregation under rice-rape rotation

摘要

ABSTRACT No-tillage and straw returning are important practices for preserving and improving soil quality for the sustainable management system. The experimental field was established in 2007 with conventional tillage (CT), conventional tillage with straw returning (CTS), no-tillage (NT), and no-tillage with straw returning (NTS) practice in rice (Oryza sativa L.)-rape (Brassica napus L.) cropping system. The soil samples were collected in 2013-2015 from 0-20 and 20-40 cm depth to investigate the effects on soil organic C (SOC), water-stable aggregation (> 5, 5-2, 2-1, 1.0-0.5, 0.25-0.5, and 5, 2-5, 1-2, and 0.25-0.5 mm aggregates. Thus, long-term combine use of NT with straw returning practices significantly improved SOC and water-stable aggregation. No-tillage and straw returning appeared to be promising and sustainable strategies to conserve SOC sequestration and stable soil aggregates in rice-rape cropping system.