不同生物炭类型及添加量对土壤碳氮转化的影响

通过室内培养试验,研究不同生物炭类型(椰壳炭、稻壳炭、柠条炭)以及生物炭添加水平对不同土壤(砖红壤和水稻土)碳素转化的影响。结果表明,在施用等量尿素的情况下,随着生物炭添加量的增加土壤的有机碳含量显著提高。对土壤氮素转化的影响总体表现一致,土壤铵态氮含量逐渐减少,而硝态氮含量逐渐增加;添加1%、2%、5%生物炭的处理土壤NH_4~+-N含量分别比对照降低了13.3%~16.0%、18.6%~28.5%、51.1%~68.8%,NO_3~--N含量比对照提高了6.4%~13.3%、12.9%~19.7%、18.4%~22.7%,这可能与添加生物炭后土壤pH升高引起的氨挥发增加有关,然而其影响程度与土壤类型、生物炭类型和生物炭添加量密切相关。

Impacts of Different Biochar Types and Application Rates on Urea Transformation in Soils

With the laboratory test, the impacts of different biochars(coconut shell, rice husk and Korshinsk Peashrubwood)and applying amounts on nitrogen transformation in two soils(Latosol and paddy soil)were studied. The results showed that organic carbon contents in the two soils significantly increased with applying biochar increase. There was the same regular pattern, ammonia nitrogen content declined, but nitrate nitrogen content increased. Compared with the control treatment, the ammonia nitrogen content in the soils applying 1%, 2% and 5% biochar respectively decreased 13.3%-16.0%, 18.6%-28.5%, 51.1%-68.8%, the nitrate nitrogen increased 6.4%-13.3%, 12.9%-19.7%, 18.4%-22.7%, which was related to increasing pH. However, the influence intensity was closely related with soil types, biochar types and applying amounts.