A Coupled Modeling and Empirical Approach to the Study of the Life History and Physiological Ecology of Cold Seep Vestimentiferans and Communities

冷渗动物及其群落生活史和生理生态研究的模型与实证耦合方法。渗透线虫及其共生体是主要的生产者，在无毒环境中为各种各样的渗透地方性和非地方性异养物种提供复杂的栖息地结构。因此，它们可以说是大陆斜坡上广泛渗透地区最重要的基石物种。最近的研究表明，有一种（至少）渗漏线虫的寿命非常长，并且可以通过身体埋藏的部分吸收溶解的气体来维持其自养的生活方式。因此，在许多方面，这些渗透植物类似于陆地环境中长寿的、生态系统结构的木本植物。我们将开发模型来解决资源获取和分配，生活史，以及冷渗动物的群落生产力，这将指导和重点冷渗动物群落的现场和实验室研究。我们建议在墨西哥湾路易斯安那州上斜坡的540至1000米深度范围内开展工作，并将包括暴露在一系列硫化物浓度下的硬基质和沉积物上的群落。我们将使用实证研究和比较方法来开发、测试和完善动态能量预算模型的预测，同时解决有关肠道聚集生理学和生态学的特定假设。我们的现场工作将以这些数学模型为指导，并与非常高效和定量的收集方法相结合，这将最大限度地从每次收集中收集信息，并为未来的研究提供材料，从而最大限度地减少我们对社区的短期和长期影响。将测量成千上万个个体的生长速度，这些数据用于估计寿命，并计算每个被评估物种分配给生长的资源。我们将确定“根”（可用于从沉积物中开采硫化物的后伸物）是否是渗漏体的一般特征，以及它们是否是环境引起的。这些模型将用于探索不同情况下根部硫化物吸收对聚集物维持的相对重要性，以及估算硫化物需求对硫化物产生的生物地球化学模型的影响。为了促进这一点，将测量环境中硫化物的浓度和跨根管和组织的扩散距离，并确定不同物种中血红蛋白的浓度和硫化物结合特性。在完整的集合和处理的集合中，将确定前体动物的生物量、大小频率、分布和繁殖状态，从而确定每个集合中所有相关动物的物种丰富度和生物量。这将使我们能够制定生活史模型，将个体模型扩大到群体水平，并对相关动物的过度生产及其使用进行建模。费舍尔对墨西哥湾的渗漏社区有着丰富的经验，并去过现场。Shea是一位理论生态学家，在陆地水生自养系统的生活史建模方面有经验。所提出的方法将大大增加我们对这些广泛而富有成效的深海群落及其对周围深海的影响的理解，并将提供一个建模框架，以关注相关和未来的调查。提出的研究将产生对深海系统的生态学、生理学和生殖生物学的基本见解，特别是化学自养系统。它们还将提供新的理论，并对现有的关于生命史策略进化的理论进行检验。

A coupled modeling and empirical approach to the study of the life history andphysiological ecology of cold seep vestimentiferans and communities.Seep vestimentiferans and their symbionts are primary producers that provide complexhabitat structure in a non-toxic setting for a diverse assortment of seep-endemic and non-endemicheterotrophic species. As such, they are arguably the most important keystone speciesin widespread areas of seepage on the continental slope. Recent work has demonstrated that onespecies (at least) of seep vestimentiferan is extremely long-lived and can support its autotrophiclife style with the uptake of dissolved gasses across buried portions of its body. Thus, in manyways, the seep vestimentiferans are analogous to long-lived, ecosystem-structuring, woody plantspecies in a terrestrial environment.We will develop models to address resource acquisition and allocation, life histories, andcommunity productivity of cold seep vestimentiferans that will guide and focus field andlaboratory studies of cold seep vestimentiferan communities. We propose to work on the upperLouisiana Slope of the Gulf of Mexico at a depth range of 540 to 1,000m and will includecommunities on both hard substrata and sediment that are exposed to a range of sulfideconcentrations. We will use empirical studies and comparative methods to develop, test thepredictions of, and refine, Dynamic Energy Budget models, while at the same time addressingspecific hypotheses concerning vestimentiferan aggregation physiology and ecology.Our in situ work will be guided by these mathematical models and interfaced with veryefficient and quantitative collection methods that will maximize the information gleaned fromeach collection and provide material for future studies, thereby minimizing our short and long-termimpact on the communities. Growth rates of thousands of individuals will be measured andthese data used to estimate the longevity and to calculate the resources allocated to growth byeach vestimentiferan species. We will determine whether "roots" (posterior extensions that canbe used to mine sulfide from within sediments) are a general feature of seep vestimentiferans andwhether they are environmentally induced. The models will be used to explore the relativeimportance of root sulfide uptake to the sustenance of aggregations in different situations and theimplications of vestimentiferan sulfide demand on biogeochemical models of sulfide production.To facilitate this, environmental concentrations of sulfide and diffusion distances across roottubes and tissues will be measured, and concentrations and sulfide binding properties of thehemoglobins in the different species will be determined. The biomass, size frequency,distribution, and reproductive state of the vestimentiferans will be determined for intactaggregations and collections processed so that the species richness and biomass of all associatedfauna in each collection can also be determined. This will allow us to formulate life historymodels, to scale up the models of individuals to the levels of aggregations, and to model excessproduction and its use by associated fauna.Fisher has extensive experience with the Gulf of Mexico seep communities and has visitedthe sites. Shea is a theoretical ecologist with experience in life-history modeling of terrestrialand aquatic autotrophic systems. The proposed approach will significantly increase ourunderstanding of these widespread and productive deep-sea communities and their impact on thesurrounding deep sea, and will provide a modeling framework to focus related and futureinvestigations. The proposed studies will yield basic insights on the ecology, physiology andreproductive biology of deep-sea systems in general and chemoautotrophic systems in particular.They will also provide new theory, and tests for existing theory on the evolution of life historystrategies.