Dissertation Research: Contributions of Charophycean Algae & Sphagnum Moss to Long-term Carbon Storage in Boreal Peatlands. Dissolved Organic Carbon Uptake & Carbon

格雷厄姆·北方泥炭地是公认的碳聚集地点。最近的数据表明，存在两种以前没有被定量评估的潜在的碳保持机制，即轮藻和泥炭藓对溶解有机碳(以糖的形式)的吸收和利用，以及轮藻和泥炭藓产生抗降解的细胞壁多酚。第一个过程从环境中去除易受影响的固定碳形式，而第二个过程产生相对长期储存的碳形式。这两个过程都干扰了细菌将固定碳转化为二氧化碳的能力，从而促进了泥炭地碳的积累。培养的轮藻和泥炭藓将用于糖运输基因的克隆和测序，以及基因表达研究。轮藻多样性和生物量的现场数据将与现场测量的pH、DOC、DIC和细菌生物量相关，并与使用实验室培养方法测量的特定物种负载糖类和产生多酚壁化合物的能力相关联。还将对泥炭泥生产耐腐蚀墙体材料和原生生殖阶段对DOC的利用进行评估。该项目的目标是改善对泥炭地碳封存数量的估计。

Graham Boreal peatlands are a recognized site of carbon accumulation. Recent data suggests the occurrence of two potential mechanisms for carbon retention that have not previously been quantitatively assessed, namely, the uptake and utilization of dissolved organic carbon (in the form of sugars), and production of degradation-resistant cell wall polyphenolics by charophytes and Sphagnum moss. The first of these processes removes liable forms of fixed carbon from the environment, while the second generates relatively long-term storage forms of carbon. Both processes interfere with the ability of bacteria to convert fixed carbon back to CO2, and thus contribute to peatland carbon accumulation. Cultured charophytes and Sphagnum will be used for cloning and sequencing of sugar transport genes, and for gene expression studies. Field data for charophyte diversity and biomass will be correlated with field measurements of pH, DOC, DIC, and bacterial biovolumes, and with species-specific abilities to load sugars and generate polyphenolic wall compounds measured with the use of laboratory cultures. Assessments of Sphagnum production of resistant wall materials and utilization of DOC by protonematal stages will also be made. The goal of the project is to improve estimates for the amount of carbon sequestered in peatlands.