Light Regulation of Carbon Partitioning and Growth of Eelgrass

海草分布在除最极地以外的所有海域的边缘，构成了世界上一些最具生产力的植物群落的基础。它们在营养循环、沉积物沉积和结合、为大型和多样化的动物提供栖息地方面发挥着重要的生态作用，并对近岸食物网做出了重大贡献。大叶藻，通常在近岸水域的单一类型林中发现，其特征是光线有限，存在缺氧的富含有机的沉积物。鳗草栖息地的性质对地下组织造成了昼夜的、往往是长期的低氧/缺氧，并严格限制了碳的获得。鳗草承受这些条件并从这些条件中恢复的能力必须是其生态成功的基础。正在进行的研究已经开始检查在这些栖息地成功种植鳗草的生理和生化机制。这项研究项目将建立在先前研究的基础上，并推动目前对整个植物碳收支的简单核算，以及决定植物对海底光环境和缺氧沉积物的综合反应的生物化学和分子特征。这项研究将探讨海底光照制度控制带状藻生存深度、生长和生产力的基本机制，并阐明该物种确保其在沿海环境中生态成功的主要生理、生化和分子特征。特别是，该项目将研究海洋带状藻(Zostera Marina)茎和根之间碳分配的控制，并启动分子检测，以确定翻译和转录事件在调节根对每日和长期缺氧的反应中的相对重要性。这个项目应该提供对控制海藻分布和碳分配策略的主要因素所需的机械理解，以便将这种复杂程度纳入该物种的生长和生产力的预测数字模型中。从这些研究中获得的知识不仅将促进我们对控制海洋底栖动物生产力的因素的了解，有助于我们对植物中起作用的适应机制的基本了解，而且还将为沉水植物的健全和知情管理提供必要的信息。

Seagrasses are distributed along the margins of all but the most polar seas and form the basis of some of the most productive plant communities in the world. They play important ecological roles in nutrient cycling, sediment deposition and binding, provision of habitat for a large and diverse fauna, and contribute significantly to nearshore food webs. Eelgrass, Zostera marina, is found typically in monotypic stands in nearshore waters characterized by light limitation and the presence of anoxic, organic-rich sediments. The very nature of eelgrass habitats imposes diurnal and often prolonged hypoxia/anoxia on subterranean tissues and severe restrictions on carbon gain. The ability of eelgrass to withstand and recover from these conditions must underlie its ecological success. Ongoing studies have begun to examine the physiological and biochemical mechanisms responsible for the success of eelgrass in these habitats. This research project will build on prior research and advance current understanding, beyond a simple accounting of whole plant carbon budgets, to the biochemical and molecular features that dictate integrated plant responses to submarine light environments and anoxic sediments. This research will address the fundamental mechanisms by which submarine light regimes control the survival depth, growth and productivity of Zostera marina, and elucidate the primary physiological, biochemical and molecular features of this species that ensure its ecological success in littoral environments. In particular, this project will investigate the controls on carbon partitioning between shoots and roots in Zostera marina, and initiate molecular examinations to determine the relative importance of translational and transcription events in regulating root responses to diurnal and prolonged anoxia. This project should provide the needed mechanistic understanding of the major factors that control the distribution and carbon allocation strategies of eelgrass, so that this level of sophistication can be incorporated into a predictive numerical model of growth and productivity for this species. The knowledge gained form these studies will not only advance our understanding of factors that control marine benthic productivity and contribute to our basic understanding of the adaptive mechanisms that function in plants, but provide information essential to sound and informed management of submerged macrophytes.