Respiratory quotient (RQ) is a parameter proposed as a tool for practical and online monitoring of petroleum hydrocarbon biodegradation. Various environmental factors and remediation conditions affect RQ values. Occasionally, actual RQ values deviate from theoretical RQ values of petroleum hydrocarbon biodegradation. In addition, different RQ calculation and interpretation approaches investigated in literature make it difficult to compare the results. In this study, different RQ calculation and interpretation methods given in the literature were compared and the effects of nitrogen biostimulation with ammonium and nitrate salts on RQ values of petroleum hydrocarbon biodegradation were investigated. Respirometric reactors were used in bioremediation of diesel fuel–contaminated soils. Ammonium sulfate and potassium nitrate were amended to enhance hydrocarbon biodegradation. Total n-alkane levels in the soils were analyzed after the incubation period. RQ values were calculated based on continuous CO₂ and O₂ measurements. Biostimulation with ammonium and nitrate led to significant contaminant biodegradation. The nitrogen source type affected RQ values significantly. It was concluded that in evaluating hydrocarbon biodegradability properties and interpreting biostimulation properties, the use of graphical RQ evaluation methods that include plotted statistical approaches allows access to more useful information than using individual theoretical RQ values.

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评估呼吸商的不同方法以及氮源对碳氢化合物生物修复的呼吸商价值的影响

呼吸商（RQ）是​​被提议作为实际和在线监测石油烃生物降解的工具的参数。各种环境因素和修复条件都会影响RQ值。有时，实际RQ值会偏离石油烃生物降解的理论RQ值。另外，文献中研究的不同的RQ计算和解释方法使得比较结果变得困难。在这项研究中，比较了文献中给出的不同RQ计算和解释方法，并研究了铵盐和硝酸盐对氮的生物刺激作用对石油烃生物降解的RQ值的影响。呼吸测定反应器用于柴油污染土壤的生物修复。修改了硫酸铵和硝酸钾以增强烃的生物降解能力。潜伏期后分析土壤中的总正烷烃水平。RQ值基于连续CO计算₂和O ₂测量。铵和硝酸盐的生物刺激导致明显的污染物生物降解。氮源类型显着影响RQ值。结论是，在评估烃的生物降解性能和解释生物刺激性能时，使用图形RQ评估方法（包括绘制的统计方法）可以获取比使用单个理论RQ值更多的有用信息。