Collaborative Research: THE BENTHIC MICROALGAL SUBSIDY IN ESTUARINE ECOSYSTEMS

河口是许多重要的商业和娱乐物种的重要栖息地。这些系统中食物网的基础是由水柱（浮游植物）和沉积物（底栖微藻）中的微藻初级产品提供的。该项目侧重于量化南卡罗莱纳州北入口河口底栖微藻对生态系统初级生产总量的贡献。然后，沿着海拔梯度（低潮到高潮区域）估算底栖微藻产量，用于评估对即将到来的海平面上升的反应。研究结果对湿地价值评估、碳信用、滋养动力学和河口生态系统的碳储量具有重要意义。这项研究是革命性的，因为它首次提供了潮间带、生态系统水平底栖微藻对总净初级产量贡献的综合测量，以评估BMA对河口生态系统过程和功能的生态重要性。研究结果可能会重构我们对河口能量流动和循环过程的理解和当前的范式。除研究活动外，该项目还包括指导研究生和本科生，努力从历史上代表性不足的群体中招募学生；将调查结果纳入教师和K-12学生的教材；以及与国家河口研究保护区合作的社区科学项目。我们目前对东南河口生态系统净初级生产量的理解缺少一个基本组成部分，事实上，这个组成部分可能提供多达三分之一的固定碳，为上层营养水平的高生物量提供燃料。以底栖微藻为基础的主要补贴的概念与传统观点相矛盾，传统观点认为浮游植物和以碎屑为基础的食物网是大多数东南河口的唯一能源来源。本项目通过表征BMA NPP的时空变异性，定量确定BMA的相对贡献，以估算生态系统水平对总系统NPP的年贡献。主要目标是测量河口潮间带BMA NPP、生物量、群落组成和相关环境变量（营养物质、粒度、孔隙度等），并将这些结果纳入GIS DEM中，以计算生态系统水平的BMA NPP。此外，GIS模型还预测了不同海平面上升情景下BMA NPP的大小和空间分布的变化。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Estuaries are nurseries that are critical habitat for many commercially and recreationally important species. The base of the food web in these systems is supplied by microalgal primary production in both the water column (phytoplankton) and the sediments (benthic microalgae). This project focuses on quantifying the contribution of benthic microalgae to total ecosystem primary production in the North Inlet Estuary, SC. Benthic microalgal production estimates along an elevational gradient (low to high tide region) are then used to assess responses to the impending sea level rise. The results have implications for wetlands valuation, carbon credits, trophodynamics, and carbon storage in estuarine ecosystems. This research is transformative in that it provides the first ever comprehensive measures of intertidal, ecosystem-level benthic microalgal contributions to total net primary production to evaluate the ecological importance of BMA for estuarine ecosystem processes and functions. The research results will likely restructure our understanding and current paradigms of energy flow and cycling processes in estuaries. In addition to the research activities, the project involves the mentorship of graduate students and undergraduates, with efforts to recruit students from historically underrepresented groups; incorporation of findings into educational materials for teachers and K-12 students; and a community science program in collaboration with the National Estuarine Research Reserve.Our current understanding of ecosystem net primary production in southeastern estuaries is missing a fundamental component that may, in fact, provide as much as a third of the fixed C fueling the high biomass of upper trophic levels. The concept of a major benthic microalgal-based subsidy contradicts the traditional views that phytoplankton and detritus-based food webs are the only energy sources for most southeastern estuaries. This project quantitatively determines the relative BMA contribution by characterizing the spatiotemporal variability in BMA NPP to estimate the annual ecosystem-level contribution to total system NPP. The primary objective is the measurement of estuarine intertidal BMA NPP, biomass, community composition, and relevant environmental variables (nutrients, grain size, porosity, etc.) along fixed transects that span the intertidal elevational gradient from mean low water to mean high water and incorporate these results in a GIS DEM to calculate ecosystem-level BMA NPP. Furthermore, the GIS model predicts shifts in the magnitude and spatial distribution of BMA NPP resulting from various sea-level rise scenarios.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.