生物碳对小麦生长和氮素平衡的影响

【目的】以棉花秸杆为原料,在不同温度下(450、600和750℃)厌氧热解制备生物碳,探讨生物碳对小麦生长和氮素吸收与平衡的影响。【方法】设置3种物料:450、600和750℃热解制备的生物碳(分别用450BC、600BC、750BC来表示);每种有机物料设置三个施用量,分别为0.5%、1.0%和2.0%(占土壤的比例);同时,以不添加物料土壤作为对照(CK)。【结果】三种温度热解制备的生物碳均对小麦生长具有一定的促进作用,可显著提高小麦地上部干物质重、氮素吸收量、土壤中氮素残留量,减少土壤小麦体系氮素表观损失量。从两茬小麦种植总体看,750℃制备的生物碳对小麦生长的促进作用最好、氮素吸收量最高、土壤氮素残留量最高、整体氮素损失最小。【结论】对于生物碳处理而言,随着热解温度的升高,小麦氮素吸收量增大、土壤氮素残留量增大、整体氮素损失降低。因此生物碳还田是提高养分利用,减少氮素损失的有效途径,从而为新疆干旱区棉花秸秆资源的合理利用和提高肥料利用率提供理论依据。

Effects of Biochar Application on Wheat Growth and Nitrogen Balance

【Objective】The project focused on the production of biochars produced from cotton stalk in conditions of high temperature pyrolysis(450,600 and 750℃).The effects of biochar on wheat growth and nitrogen ba lance in soil-plant system were investigated with a pot experiment.【Method】The experimental design was a 3*3 factorial with four materials levels and three ma terials dosage.Three materials were biochar produced at 450,600,and 750 ℃,(referred as 450BC,600BC,and 750BC) and three materials dosage were 0.5%, 1% and 2% by soil weight,Additionally,un-amended soil was set as control(ref erred as CK).【Result】The pot experiment in a green house showed that wheat gr owth and nitrogen uptake were promoted significantly by biochar.Dry matter weig ht,nitrogen accumulation and nitrogen residue in soil of wheat under cotton str aw and biochar treatments were significantly higher than that in CK and nitrogen apparent loss under cotton straw and biochar treatments were significantly lowe r than that in CK.From the whole two generation of the successful wheat growth. The wheat grew the bes t and nitrogen accumulation and nitrogen residue in soil were both the highest, and nitrogen apparent loss was the lowest under the 750BC treatment【Conclusion】As f ar as biochar s treatment was concerned,with the increase of temperature carbonization,nitr ogen accumulation and nitrogen residue were both higher and nitrogen apparent lo ss was lower.So these results suggest that adding biochar to soil was the effec tive way to promote nitrogen availability usage and reduce nitrogen loss form so il-plant system,which could provide theoretical basis for improving the fertili zer utilization ratio and cotton straw resource usage in xinjiang arid areas.