添加生物炭对滨海盐渍型水稻土供氮能力的影响

Effect of Biochar Addition on Nitrogen Supplying Capacity in Coastal Saline Paddy Soil

采用室内淹水培养的方法,研究了添加等碳量的水稻秸秆生物炭、腐熟水稻秸秆和普通水稻秸秆及不同淹水培养时间(淹水培养30 d、60 d、90 d和180 d)对滨海盐渍型水稻土供氮能力的影响,为制定合理的秸秆还田措施提供科学参考。结果表明,各处理均可以提高土壤有机碳含量和碳氮比(C/N),添加生物炭的土壤有机碳和C/N显著高于其他处理(P<0.05)。各处理对土壤氮素矿化有显著影响,其中,添加生物炭处理明显提高了土壤氮素矿化量。各处理土壤供氮能力均随培养时间的延长呈现先增加后降低的趋势,培养90 d时土壤氮素矿化量最高。添加生物炭可以促进滨海盐渍型水稻土氮素的矿化,增强土壤供氮能力。

An indoor water flooding incubation experiment was designed to study the effect of rice straw-derived biochar,decomposed and not decomposed rice straw with equivalent carbon application and the time of incubation on the nitrogen supplying capacity of coastal saline paddy soil,and to provide a scientific reference for reasonable straw returning method. Results showed that the contents of soil organic carbon and ratio of carbon to nitrogen increased through adding different rice straw treatments,and they were significantly higher with adding rice straw-derived biochar than those of other treatments (P<0.05). All different straw treatments had a significant effect on soil nitrogen mineralization,and the biochar addition treatment significantly improved the quantity of soil nitrogen mineralization. The soil nitrogen supplying capacity of each treated soil increased first and then decreased with the prolongation of incubation time. The quantity of soil nitrogen mineralization was the highest at 90th days. The addition of biochar can promote the mineralization of nitrogen and enhance soil nitrogen supply in coastal saline soil.