Johansson A E, Gustavsson A-M, Oquist M G, Svensson B H
Department of Microbiology, Swedish University of Agricultural Sciences, Uppsala S-750 07, Sweden.
Water Res. 2004 Nov;38(18):3960-70. doi: 10.1016/j.watres.2004.07.008.
Constructed wetlands for wastewater treatment have many advantages. They can be used for several purposes, for example, to reduce levels of organic matter and nutrients, and to retain toxic metals. However, most wetlands are inherently net sources of gaseous compounds like methane and nitrous oxide, which are of environmental concern due to their rapid current accumulation in the atmosphere and their potent global warming capacity. In order to determine the flux of methane from a constructed wetland a study was conducted over two growth seasons on a pilot scale wetland constructed to reduce nutrient levels in secondary treated wastewater. The emissions for the spring to autumn period averaged 141 mg CH(4)m(-2)d(-1) (S.D.=187), ranging from consumption of 375 mg CH(4)m(-2)d(-1) to emissions of 1739 mg CH(4)m(-2)d(-1). The spatial and temporal variations were large, but could be accounted for by measured environmental factors. Among these factors, sediment and water temperatures were significant in all cases and independent of the scale of analysis (r(2) up to 0.88).
用于废水处理的人工湿地有许多优点。它们可用于多种目的，例如，降低有机物和营养物水平，以及截留有毒金属。然而，大多数湿地本质上是甲烷和一氧化二氮等气态化合物的净排放源，由于它们目前在大气中迅速积累且具有强大的全球变暖能力，因而受到环境关注。为了确定人工湿地的甲烷通量，在一个为降低二级处理废水中营养物水平而建造的中试规模湿地进行了为期两个生长季节的研究。春季至秋季期间的排放量平均为141毫克CH₄·米⁻²·天⁻¹（标准差 = 187），范围从消耗375毫克CH₄·米⁻²·天⁻¹到排放1739毫克CH₄·米⁻²·天⁻¹。空间和时间变化很大，但可以由实测环境因素来解释。在这些因素中，沉积物和水温在所有情况下都很显著，且与分析尺度无关（r²高达0.88）。
