A field validation of three biochar-amended soil covers (2%, 10%, and 100% biochar-amended soils) along with a soil control cover was conducted within the intermediate cover of an active municipal solid waste (MSW) landfill in conjunction with laboratory studies evaluating the effect of biochar in enhancing methane (CH₄) oxidation in cover soils. Baseline CH₄ emissions and pre-existing site conditions were characterized prior to installation of test plots simulating three cover designs evaluated in related laboratory studies. Static chamber measurements of surface CH₄ fluxes and sampling of soil pore gas at different depths were conducted across the 8-month monitoring period to assess cover performance. Surface fluxes from the test plots exhibited wide spatial variability, with one location emitting fluxes > 1100 g CH₄ m⁻² day⁻¹ in one survey. Potential rates of CH₄ oxidation were determined in batch assays of exhumed soil core subsamples following termination of the field trial and ranged from ~1 to 350 μg CH₄ g⁻¹ day⁻¹. The heterogeneity of the waste led to nonuniform CH₄ loads in the test plots. The soil control test plot was exposed to higher CH₄ loads and biochar-amended test plots were exposed to significantly lower CH₄ loads. As a result, the soil control test plot showed higher CH₄ oxidation rates (257–289 μg CH₄ g⁻¹ day⁻¹) than the biochar-amended test plots. Similarly, the soil control plot also showed higher relative abundance of methanotrophs which was positively correlated with the CH₄ oxidation rates. The test plot with 10% biochar-amended soil experienced CH₄ loads nearly 25% of that in soil control and still showed CH₄ oxidation rates (260 μg CH₄ g⁻¹ day⁻¹) comparable to that of soil control which showed the efficacy of biochar amendment in enhancing CH₄ oxidation rates. The environmental and CH₄ exposure conditions affected the microbial community composition in the test plots and showed the dominance of type I methanotrophic genus such as Methylomonas and Crenothrix spp. Overall, the waste heterogeneity led to nonuniform CH₄ exposure conditions at each test plot making it hard to distinctly quantify the effect of biochar amendment on CH₄ oxidation rates.

在一个活动的城市固体垃圾（MSW）垃圾填埋场的中间覆盖层中，结合使用三种生物炭改良过的土壤覆盖物（2％，10％和100％生物炭改良过的土壤）以及土壤控制覆盖层，进行了现场验证，并与评估生物炭增强覆盖土壤中甲烷（CH ₄）氧化作用的实验室研究。在安装测试地块之前，要对基线CH ₄排放量和预先存在的场地条件进行表征，以模拟在相关实验室研究中评估的三种覆盖设计。表面CH _4的静态腔室测量在整个8个月的监测期内，对不同深度的土壤孔隙气体进行了通量和采样，以评估覆盖性能。来自测试地块的表面通量表现出宽广的空间变异性，在一个调查中，一个位置发出的通量> 1100 g CH ₄ m ^-2 day ^-1。在田间试验结束后，在挖掘出的土壤核心子样品的分批测定中确定了CH ₄氧化的潜在速率，其范围为〜1至350μgCH ₄ g ^-1天^-1。废物的异质性在测试区中导致CH ₄负荷不均匀。土壤控制试验区暴露于较高的CH ₄负荷和生物炭修正的试验区暴露在显着较低的CH ₄负荷下。结果，土壤控制试验区显示出比生物炭改良试验区更高的CH ₄氧化速率（257–289μgCH ₄ g ^-1天^-1）。同样，土壤控制区也显示出较高的甲烷营养菌相对丰度，这与CH ₄氧化速率呈正相关。用10％的生物炭改良过的土壤的试验区的CH ₄负荷接近土壤对照的25％，并且仍显示CH ₄氧化速率（260μgCH ₄ g ^-1天^-1）可与土壤控制相比，后者显示了生物炭改良剂在提高CH ₄氧化速率方面的功效。环境和CH ₄暴露条件影响测试区中的微生物群落组成，并显示I型甲烷营养型属（如甲基单孢菌和Crenothrix spp）的优势。总体而言，废物的异质性导致每个测试区的CH ₄暴露条件不均匀，从而难以明确量化生物炭改良剂对CH ₄氧化速率的影响。