The University of Edinburgh, UK.
Chemosphere. 2010 Jan;78(5):493-9. doi: 10.1016/j.chemosphere.2009.11.042.
Constructed wetlands are increasingly used for water pollution treatment but may also be sources of the greenhouse gas CH(4). The effect of addition of two potential inhibitors of methanogenesis - iron ochre and gypsum - on net CH(4) emissions was investigated in a constructed wetland treating farm runoff in Scotland, UK. CH(4) fluxes from three 15-m(2) wetland plots were measured between January and July 2008 in large static chambers incorporating a tunable diode laser, with application of 5tonha(-1) ochre and gypsum in May. CH(4) fluxes were also measured from control and ochre- and gypsum-treated wetland sediment cores incubated at constant and varying temperature in the laboratory. Ochre addition suppressed CH(4) emissions by 64+/-13% in the field plot and >90% in laboratory incubations compared to controls. Gypsum application of 5tonha(-1) in the field and laboratory experiments had no effect on CH(4) emissions, but application of 10tonha(-1) to a sediment core reduced CH(4) emissions by 28%. Suppression of CH(4) emissions by ochre application to sediment cores also increased with temperature; the reduction relative to the control increased from 50% at 17.5 degrees C to >90% at 27.5 degrees C. No significant changes in N removal or pH and potentially-toxic metal content of sediments as the result of inhibitor application were detected in the wetland during the study.
人工湿地越来越多地被用于水污染处理，但也可能是温室气体 CH(4) 的来源。本研究在苏格兰一个处理农场径流的人工湿地中，调查了两种潜在甲烷生成抑制剂 - 铁赭石和石膏 - 添加对净 CH(4) 排放的影响。2008 年 1 月至 7 月期间，在三个 15m(2) 的湿地小区中，通过大型静态室和可调二极管激光，在 5t·ha(-1) 赭石和石膏的作用下，测量了 CH(4)通量。还测量了来自对照和赭石和石膏处理的湿地沉积物核心在实验室中恒定和变化温度下的 CH(4)通量。与对照相比，赭石在田间小区和实验室培养物中分别减少了 64+/-13%和>90%的 CH(4)排放。在田间和实验室实验中，5t·ha(-1) 的石膏应用对 CH(4)排放没有影响，但 10t·ha(-1) 的石膏应用使 CH(4)排放减少了 28%。在沉积物核心中，随着温度的升高，赭石的应用对 CH(4)排放的抑制作用也增加了；与对照相比，相对减少量从 17.5°C 时的 50%增加到 27.5°C 时的>90%。在研究期间，湿地中未检测到抑制剂应用对 N 去除或沉积物 pH 值和潜在有毒金属含量的显著变化。
