| This article has been：Browse 230Times Download 24Times |
scan it! |
|
|
| DOI：10.13522/j.cnki.ggps.2025404 |
|
| Effects of wet-dry cycles on efficacy of biochar in improving soil physicochemical properties and rice yield |
|
Yang Yifan, Song Xishan, Jiang Zewei, Xu Yi, Liu Fangping, Xu Tao, Xu Yi, Yang Shihong
|
|
1. College of Agricultural Science and Engineering, Hohai University, Nanjing 210098, China; 2. College of Soil and Water Conservation, Hohai University, Nanjing 210098, China; 3. Jiangxi Irrigation Experiment Central Station, Nanchang 330201, China;
4. Nanjing Hydraulic Research Institute, Nanjing 210029, China; 5. Jiangsu Engineering Research Center for Efficient Utilization of Agricultural Soil and Water Resources and Carbon Sequestration & Emission Reduction, Nanjing 210098, China
|
| Abstract: |
| 【Objective】Biochar can improve soil quality and crop productivity, but its environmental aging, including repeated dry-wet cycles, may alter its properties and efficacy. This study experimentally investigated how dry-wet cycle-induced biochar aging affects its ability to regulate paddy soil properties and rice growth.【Method】The experiment was conducted in pots from 2023 to 2024 using rice straw biochar. It consisted of four treatments: biochar not undergoing to dry-wet cycling (CK), biochar undergoing three dry-wet cycles (C3), six dry-wet cycles (C6), and ten dry-wet cycles (C10). Changes in soil pH, soil organic carbon (SOC), dissolved organic carbon (DOC), soil nitrogen forms, redox potential (Eh), rice yield, and irrigation water-use efficiency were measured under each treatment.【Result】①Biochar undergoing six dry-wet cycles (C6) produced the greatest increases in soil pH, SOC, and DOC contents and optimized soil redox conditions during key rice growth stages. ②C6 significantly increased soil ammonium nitrogen content at the tillering stage and promoted nitrate nitrogen accumulation at the jointing- booting stage, thereby improving soil nitrogen retention and supply. ③Compared with CK, C6 achieved the highest grain yield and irrigation water-use efficiency, increasing grain yield in 2023 and 2024 by 11.2% and 14.7%, respectively, while reducing irrigation water use by 4.9% and 3.9%, respectively.【Conclusion】Subjecting biochar to undergo six dry-wet cycles enhanced its capacity to improve paddy soil properties by optimizing soil pH, carbon and nitrogen balance, and redox condition, thereby creating a favorable condition for rice growth and simultaneously increasing grain yield and irrigation water-use efficiency. |
| Key words: dry-wet cycle aged biochar paddy soil carbon and nitrogen cycling irrigation water use efficiency |
|
|
