During the past three decades, constructed wetlands have become an integral part of the suite of technologies for removing domestic and industrial wastewater contaminants. The use of constructed wetlands has disproportionately focused on domestic and agricultural wastewaters and storm water runoff and less on oil and gas-related produced water. In this context, the cumulative effect of environmental factors on the treatment/removal efficiency of contaminants in produced water is underserved by research. Therefore, this study assessed the effect of environmental factors (temperature, dissolved oxygen, oxidation–reduction potential, and pH) on contaminant removal efficiency in free water surface flow constructed wetland (FWSFCW) using ordinary least squares regression and experimental data from a waste treatment facility in Ghana. The results showed that environmental factors did not systematically vary across the experimental group and control set-up. Generally, the environmental factors explained relatively far less of the variance in contaminant removal efficiency compared with the plant species (Typha latifolia, Ruellia simplex and Alternanthera philoxeroides). Environmental factors cumulatively explained only 1.3%, 16.4%, 22.6%, and 5.6% of the variance in removal efficiency of BOD, COD, oil and grease, and total coliform bacteria, respectively. Temperature was the most important environmental predictor of the removal of BOD and phosphorus whereas DO was most important for removing nitrates and total coliform bacteria. ORP and pH were the most important predictors of COD, and oil and grease, respectively. These findings underscore the complex relationships among environmental factors and contaminant removal efficiency and the need for contaminant management practices and remedial techniques that address these complexities.

在过去的三十年中，人工湿地已成为去除生活和工业废水污染物的整套技术的有机组成部分。人工湿地的使用不成比例地集中在生活和农业废水和雨水径流上，而很少涉及与石油和天然气有关的采出水。在这种情况下，研究不足以解决环境因素对采出水中污染物的处理/去除效率的累积影响。因此，本研究使用普通最小二乘回归和废物处理的实验数据评估了环境因素（温度，溶解氧，氧化还原电位和pH）对自由水表面流人工湿地（FWSFCW）中污染物去除效率的影响。加纳的工厂。结果表明，环境因素在实验组和对照组之间没有系统地变化。通常，与植物物种相比，环境因素所解释的污染物去除效率差异要小得多（香蒲，单叶芸香和灰飞虱（Alternanthera philoxeroides）。环境因素累计仅分别解释了BOD，COD，油脂和总大肠菌群的去除效率差异的1.3％，16.4％，22.6％和5.6％。温度是去除BOD和磷的最重要的环境预测指标，而DO对于去除硝酸盐和总大肠菌群则最重要。ORP和pH分别是COD以及油和油脂的最重要预测指标。这些发现强调了环境因素与污染物去除效率之间的复杂关系，以及解决这些复杂性的污染物管理实践和补救技术的需求。