氧化铁辅助农业固碳减排的技术探索

通过选取水稻秸秆、猪粪、污泥和颗粒有机肥，添加氧化铁后分别进行室内好气培养（25℃）和田间填埋矿化（夏季），以探索农业固碳减排的技术途径。结果表明，室内好气培养条件下，氧化铁明显降低了水稻秸秆、猪粪、污泥和颗粒有机肥的CO2释放速率，整个培养期间的CO2累积释放量分别由未添加氧化铁的10934．45、5426．12、5288．43和794．90mgCO2-C·kg^-1降低为添加氧化铁的125．47、1535．15、1473．36和498．72mgCO2-C·kg^-1，以水稻秸秆的效果最为显著。田间填埋条件下，除了颗粒有机肥的有机碳降解速率基本未受氧化铁影响外，其余3种有机物料在每一取样阶段的有机碳降解速率均受到了氧化铁的有效抑制。填埋90d后，水稻秸秆、猪粪和污泥的有机碳降解速率分别由未添加氧化铁的34．06％、14．91％和19．90％降低为添加氧化铁的24．25％、9．45％和14．24％，也以水稻秸秆的效果最为显著。可见，无论是室内好气培养还是田间填埋矿化，氧化铁均表现出对有机物料矿化降解的有效抑制作用，具有明显的有机碳固持能力。

An Approach of C Sequestration and Mitigation Inspired by Ferric Oxide from Paddy Soil

In order to explore the approach and method of C sequestration and mitigation, the effect of ferric oxide on reducing the mineralization of organic materials （rice straw, pig manure, sewage sludge and granule organic fertilizer ） under aerobic incubation and field landfill conditions was explored and elucidated. The results showed that ferric oxide significantly decreased the C mineralization rate of organic materials at each incubation time, it resulted in a significant reduction of the cumulative evolution of CO2 from organic materials during the early incubation period of 23 days, from 10 934.45, 5 426.12, 5 288.43 and 794.90 mg CO2-C·kg^-1 to 125.47, 1 535.15, 1 473.36 and 498.72 mg CO2-C·kg^-1 for rice straw, pig manure, sewage sludge and granule organic fertilizer respectively, being more distinct for rice straw. Under the field landfill condition, except for granule organic fertilizer, the organic carbon remained for rice straw, pig manure and sewage sludge, sampled and determined after 30, 60 and 90 days since the beginning of field landfill process, was distinctively higher in organic materials granulated with Fe oxyhydrates than in those granulated with deionized-water. The decomposition rate of organic materials during the entire 90 days 0f field landfill was reduced by ferric oxide from 34.06%, 14.91% and 19.90% to 24.25%, 9.45% and 14.24% for rice straw, pig manure and sewage sludge respectively, being more distinct for rice straw. Both of aerobic incubation and field landfill indicated distinct effect of ferric oxide on reducing the C mineralization and decomposition in organic materials.