Methane production usually increases from the acidic sphagnum-dominated ombrotrophic peatlands to minerotrophic ones with more neutral pH and higher coverage of vascular plants. Along this ombrotrophic–minerotrophic gradient, pH, microbial communities, and properties of dissolved organic matter in porewater all vary greatly. The hydrographic change resulted from permafrost thaw and projected global warming can potentially connect the minerotrophic and ombrotrophic sites via porewater and turn acidic bogs to minerotrophic fens. It is thus very important to investigate how the anaerobic carbon degradation processes respond to changes in fundamental factors like pH, temperature, properties of dissolved organic matter, and microbial communities resulted from such hydrographic change. In this study, one ombrotrophic (pH = 3.9) and one minerotrophic peatland site were sampled in Fairbanks, Alaska in Sep 2017 and a 42-day-period anaerobic laboratory incubation was conducted to study the changes in anaerobic carbon degradation processes including primary and secondary fermentation, methanogenesis, and acetogenesis when pH, temperature, and porewater were manipulated individually and a combination of two or three of these factors. The results suggested lowering pH would inhibit many anaerobic carbon degradation processes in the minerotrophic peatland except primary fermentation. Elevating pH in the ombrotrophic site did not stimulate its methanogen community, but primary fermentation responded better with increasing pH than with increasing temperature alone. Replacing the porewater in the minerotrophic site with that from the ombrotrophic site with high aromaticity did not inhibit methanogenesis but potentially brought in highly efficient primary fermenters. Acetoclastic methanogenesis, acetogenesis, and syntrophy only exist in the minerotrophic site but not at the ombrotrophic one. Porewater from the minerotrophic site could potentially introduce acetoclastic methanogens and syntrophs to the ombrotrophic site but would not make them active unless both pH and temperature were increased. When ground water connects ombrotrophic and minerotrophic peatlands due to thawing of permafrost, secondary fermenters and acetoclastic methanogens could be introduced to acidic bogs and cooperate efficiently to degrade the stored carbon in ombrotrophic peatlands especially under elevated temperature conditions.

中文翻译：

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pH，温度和类似腐殖质的物质对富营养化和中营养化阿拉斯加泥炭地厌氧碳降解和甲烷生成的影响。

甲烷的生产通常从酸性泥炭为主的非营养性泥炭地增加到中性pH值更高且维管植物覆盖率更高的中性营养泥炭地。沿着这种营养养分-营养养分梯度，pH，微生物群落以及孔隙水中溶解的有机物的性质都相差很大。多年冻土融化和预计的全球变暖导致的水文变化有可能通过孔隙水将矿化和非营养化位点连接起来，并将酸性沼泽变成化石。因此，研究厌氧性碳降解过程如何响应诸如水文变化导致的pH，温度，溶解有机物特性和微生物群落等基本因素的变化非常重要。在这项研究中，一个营养体（pH = 3）。9）并于2017年9月在阿拉斯加的费尔班克斯采样了一个矿化的泥炭地，并进行了为期42天的厌氧实验室培养，以研究厌氧碳降解过程的变化，包括一次和二次发酵，产甲烷和在pH值下产乙酸的过程。温度和孔隙水分别进行控制，也可以将其中两个或三个因素进行组合处理。结果表明，降低pH会抑制除原始发酵之外的中营养泥炭地许多厌氧碳降解过程。促营养位点的pH升高并不会刺激其产甲烷菌群落，但初级发酵对pH值的响应要比对单独温度的响应更好。用具有高芳香性的来自营养营养位点的孔隙水代替矿物营养位点的孔隙水不会抑制产甲烷作用，但是可能带来高效的初级发酵罐。破骨细胞的产甲烷，产乙酸和同养仅存在于营养营养位点，而不存在于营养营养位。来自矿化营养位点的孔隙水可能会向产营养化位点引入乙酰碎屑产甲烷菌和同养菌，但除非pH和温度均升高，否则它们不会具有活性。当由于永久冻土的融化而使地下水与非营养型泥炭地和泥质营养型泥炭地相连时，可将次级发酵罐和乙酰碎裂的产甲烷菌引入酸性沼泽，并有效地协同作用，以降解非营养型泥炭地中的碳，尤其是在高温条件下。