Biological and Photochemical Transformations of Dissolved Organic Matter in a Subtropical Estuarine Ecosystem

Benner 溶解有机物（DOM）是大多数水生生态系统中有机物的主要形式，是地球上最大的有机碳反应库之一。DOM是分解微生物的主要碳源和能量来源。这些微生物负责水生生态系统中的大部分呼吸和碳氮循环。这些研究的重点是DOM的循环在一个浅的亚热带河口，是高生产力和占主导地位的海草。生物和光化学途径被假设为主导DOM分解的相互作用过程。因此，从生态系统的角度来看，阳光可以作为有机物非生物降解和营养物质再生的重要能源。 浅层水生生态系统可能正在接受以前未被认识到的来自阳光的能量补贴，这增强了降解和再生过程，从而提高了系统的总体生产力。这一点很重要，因为在水生生态系统中，尚未详细研究生态系统接受的阳光量与退化率之间的相互作用。阳光可以通过增强光合作用和分解来刺激生产力。

BENNER Dissolved organic matter (DOM) is the dominant form of organic matter in most aquatic ecosystems and is one of the largest reactive reservoirs of organic carbon on Earth. DOM is the major source of carbon and energy for decomposer microorganisms. These microorganisms are responsible for most of the respiration and carbon and nitrogen cycling in aquatic ecosystems. These studies focus on the cycling of DOM in a shallow subtropical estuary that is highly productive and dominated by seagrasses. Biological and photochemical pathways are hypothesized to be interacting processes which dominate DOM decomposition. Thus, from an ecosystem perspective, sunlight can serve as an important energy source for the non-biological degradation of organic matter and the regeneration of nutrients. Shallow aquatic ecosystems may be receiving a previously unrecognized energy subsidy from sunlight that enhances degradative and regenerative processes and thereby increases the overall productivity of the system. This is important because the interaction between the amount of sunlight an ecosystem receives and the rates of degradation have not been studied in detail in aquatic ecosystems. Sunlight may stimulate productivity both by enhancing photosynthesis and decomposition.