This study was conducted to evaluate (i) the characteristics of ammonia gas emissions from soybean cultivation soils amended with varying levels of urea and soil water, and (ii) the rate of reduction in ammonia emissions that could be obtained by applying mixed microorganisms (MM) to the urea-treated soils. The ammonia gas emissions from all treatments except the control were highest on day 2 of a laboratory-scale experiment and decreased gradually thereafter. The ammonia gas emissions from the soils increased with increasing urea and soil water contents. However, there were less emissions from soils treated with MM than those from the urea only treatment, and emissions also decreased significantly as the concentration of MM increased. In a field-scale experiment, the total cumulative emissions of ammonia from soil treated with a combination of chemical fertilizers and MM was reduced to 85.8% of that from the soil treated with chemical fertilizers only. Although we infer that MM can be used as an agent to reduce ammonia gas emissions from actual soils used for soybean cultivation, our knowledge of the processes involved in reducing ammonia emissions using microbial treatment is still limited. Consequently, further studies are required to investigate the efficient control of ammonia gas emissions from agricultural soils through the application of microorganisms.

中文翻译：

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混合微生物处理对大豆栽培土壤氨气排放的影响

进行这项研究的目的是评估（i）尿素和土壤水含量不同而改良的大豆栽培土壤中氨气排放的特征，以及（ii）应用混合微生物（MM）可以减少氨气排放的速率）到尿素处理过的土壤。在实验室规模的实验的第2天，除对照组外，所有处理的氨气排放量最高，此后逐渐降低。土壤中氨气的排放随着尿素和土壤水分的增加而增加。但是，用MM处理的土壤的排放量少于仅使用尿素处理的土壤，并且随着MM浓度的增加，排放量也显着减少。在现场规模的实验中，使用化肥和MM混合处理的土壤中氨的总累积排放量减少到仅使用化肥处理的土壤的氨累积排放量的85.8％。尽管我们推断MM可以用作减少大豆种植实际土壤中氨气排放的媒介，但我们对使用微生物处理减少氨气排放过程的知识仍然有限。因此，需要进一步的研究来研究通过施用微生物有效控制农业土壤中氨气的排放。我们对使用微生物处理减少氨气排放所涉及的过程的知识仍然有限。因此，需要进一步的研究来研究通过施用微生物有效控制农业土壤中氨气的排放。我们对使用微生物处理减少氨气排放所涉及的过程的知识仍然有限。因此，需要进一步的研究来研究通过施用微生物来有效控制农业土壤中氨气的排放。