Rice rhizodeposition and carbon stabilisation in paddy soil are regulated via drying-rewetting cycles and nitrogen fertilisation
| Autor: | Chengli Tong, Olga Shibistova, Tida Ge, Jinshui Wu, Georg Guggenberger, Cornelius Talade Atere, Zhenke Zhu, Davey L. Jones |
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| Rok vydání: | 2017 |
| Předmět: |
0106 biological sciences
Rhizosphere Irrigation Chemistry Soil Science 04 agricultural and veterinary sciences Silt 01 natural sciences Microbiology Agronomy Soil water Shoot 040103 agronomy & agriculture 0401 agriculture forestry and fisheries Water-use efficiency Soil fertility Agronomy and Crop Science Water use 010606 plant biology & botany |
| Zdroj: | Biology and Fertility of Soils. 53:407-417 |
| ISSN: | 1432-0789 0178-2762 |
| Popis: | This study aimed to better understand the stabilisation of rice rhizodeposition in paddy soil under the interactive effects of different N fertilisation and water regimes. We continuously labelled rice (‘Zhongzao 39’) with 13CO2 under a combination of different water regimes (alternating flooding-drying vs. continuous flooding) and N addition (250 mg N kg−1 urea vs. no addition) and then followed 13C incorporation into plant parts as well as soil fractions. N addition increased rice shoot biomass, rhizodeposition, and formation of 13C (new plant-derived C) in the rhizosphere soils under both water regimes. By day 22, the interaction of alternating flooding-drying and N fertilisation significantly increased shoot and root 13C allocations by 17 and 22%, respectively, over the continuous flooding condition. The interaction effect also led to a 46% higher 13C allocation to the rhizosphere soil. Alone, alternating water management increased 13C deposition by 43%. In contrast, N addition increased 13C deposition in rhizosphere soil macroaggregates under both water regimes, but did not foster macroaggregation itself. N treatment also increased 13C deposition and percentage in microaggregates and in the silt and clay-size fractions of the rhizosphere soil, a pattern that was higher under the alternating condition. Overall, our data indicated that combined N application and a flooding-drying treatment stabilised rhizodeposited C in soil more effectively than other tested conditions. Thus, they are desirable practices for improving rice cropping, capable of reducing cost, increasing water use efficiency, and raising C sequestration. |
| Databáze: | OpenAIRE |
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