Development of a Coupled Global Circulation/Adaptive Food Web Model to Explain Carbon Cycling in the Ocean

开发耦合的全球循环/自适应食物网模型来解释海洋中的碳循环

• 批准号: 0097335
• 负责人: Edward Laws
• 金额: $ 20.01万
• 依托单位: University of Hawaii
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-06-15 至 2004-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0097335&HistoricalAwards=false
• 关键词: Development; Coupled; Global; Circulation; Adaptive

This research will be on the development of a food web model that can be used to predict export production and to characterize the nature of the carbon exported to the interior of the ocean. The model will be similar to the food web model developed conceptually at the 1999 Synthesis and Modeling (SMP) food web work-shop in Keystone, Colorado. In the model phytoplankton are envisioned as consisting of five functional groups, small phytoplankton such as Synechococcus and Prochlorococcus, diatoms, coccolithophores, Phaeocystis, and nitrogen fixers. Division of the phytoplankton in this manner is hypothesized to be necessary to explain the dependence of export ratios on temperature and primary production, to account for the allocation of exported carbon between calcium carbonate, particulate organic carbon, and dissolved organic carbon, and to take into account various methods of ballasting (fecal pellets, calcium carbonate, and silica) that influence the sinking and remineralisation rates of particulate carbon. A distinguishing characteristic of the model is the assumption that open ocean biological communities adapt to environmental conditions in a way that tends to maximize the stability of the steady state condition toward which the communities evolve. This same hypothesis has previously been tested with a simpler food web model in which the phytoplankton are envisioned as consisting of only two functional groups, small and large phytoplankton. The success of that previous model, which was developed with funding from the first phase of the SMP, has provided the motivation for extending this same approach to the more complex model with five functional phytoplankton groups. It is hypothesized that a stable coupled physical-biological model of the ocean will require that the biological component be adaptive. With respect to export production, specific questions to be addressed with the model will include the following:1. How much of the organic carbon is exported as dissolved organic carbon (DOC) and how much as particulate carbon (PC)2. Of the PC export, how much is exported as particulate organic carbon (POC) and how much as carbonate carbon (CC)3. To what extent is the exported POC ballasted by silica and/or carbonate or sequestered by incorporation into encapsulated fecal pelletsA time-dependent version of the model may be incorporated into a GCM at a later date.

这项研究将涉及开发一个食物网模型，用于预测出口生产，并说明向海洋内部出口的碳的性质。该模型将类似于1999年在科罗拉多基斯通的综合与建模（SMP）食物网工作室概念上开发的食物网模型。在该模型中，浮游植物被设想为由五个功能组组成，小型浮游植物，如聚球藻和原绿球藻，硅藻，颗石藻，棕囊藻和固氮菌。以这种方式划分浮游植物被假设为是必要的，以解释输出比率对温度和初级生产的依赖性，以说明输出碳在碳酸钙、颗粒有机碳和溶解有机碳之间的分配，并考虑到压载的各种方法（粪粒、碳酸钙和二氧化硅），其影响颗粒碳的沉降和再矿化速率。该模型的一个显着特点是假设开放的海洋生物群落适应环境条件的方式，往往最大限度地提高稳定状态的条件下，社区的发展。这一假设之前已经用一个更简单的食物网模型进行了测试，在这个模型中，浮游植物被设想为只包括两个功能组，小型和大型浮游植物。先前的模型是在SMP第一阶段的资助下开发的，其成功为将同样的方法扩展到具有五个功能性浮游植物群的更复杂的模型提供了动力。据推测，一个稳定的耦合的物理-生物模式的海洋将需要的生物组件是适应性的。在出口生产方面，该模型将解决的具体问题包括：1.有多少有机碳以溶解有机碳（DOC）的形式输出，有多少以颗粒碳（PC）的形式输出。在PC出口中，有多少是以颗粒有机碳（POC）的形式出口的，有多少是以碳酸盐碳（CC）的形式出口的。在何种程度上，输出的POC被二氧化硅和/或碳酸盐压载，或通过掺入胶囊化粪粒而被隔离。