A New Method to Quantify the Terrestrial Input to the Pool of Dissolved Organic Matter in the Ocean

9503257孵化器尽管海洋中的溶解有机碳(DOM)在全球碳的生物地球化学循环中发挥着重要作用，但我们对其组成和来源知之甚少。传统上，陆地对DOM的贡献是通过分析确定的CuO氧化降解产生的木质素衍生物质的数量来估计的。近年来，一种新的热降解技术已经成为检测木质素化学成分的有力工具。这项拟议的研究旨在开发和评估这一技术，用于表征海洋和河流系统中DOM中的木质素。除了对木质素衍生物质表现出更高的专属性外，与传统的CuO氧化方法相比，在大多数现代实验室中很容易实施(热解/气体氢氧化四甲基铵)层析方法。获得了类似的木质素苯酚参数，与CuO方法不同，该技术被认为可以从已被广泛降解的样品中恢复木质素特征。如果将该方法与CuO方法进行比较，它将为评价海洋和河流DOM的陆地成分提供一种更快速、更实用的方法。

9503257 HATCHER Although dissolved organic carbon (DOM) in the oceans plays a major role in the global biogeochemical cycling of carbon, we know little of its known composition and origin. Terrestrial contribution to the DOM has traditionally been estimated from analytically determined amounts of lignin-derived materials produced from oxidative degradation by CuO. Recently, a new thermal degradative technique has emerged as a powerful tool to examine the chemical components of lignin. This proposed study seeks to develop and evaluate this technique for the characterization of lignin in DOM from marine and riverine systems. Aside from showing greater specificity for lignin-derived material, the method (thermolysis/gas) chromatography with teramethyl ammonium hydroxide) is easily implemented in most modern laboratories, in contrast to the traditional CuO oxidation. Similar lignin phenol parameters are obtained and the technique is believed to recover the lignin signature from samples which have been extensively degraded, unlike the CuO method. If this method is tested to compare well with the CuO procedure, it would provide a rapid and more easily applied method of evaluating the terrestrial composition of marine and riverine DOM.