Collaborative Research: Macrofaunal community effects on benthic exchange fluxes

合作研究：大型动物群落对底栖交换通量的影响

基本信息

批准号：
0751882
负责人：
Christof Meile
金额：
$ 15.86万
依托单位：
University of Georgia Research Foundation Inc
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2008
资助国家：
美国
起止时间：
2008-04-01 至 2012-03-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=0751882&HistoricalAwards=false
关键词：
Collaborative Research Macrofaunal community effects

项目摘要

The seafloor plays a critical role in the elemental cycling within shallow water ecosystems. Although the coastal benthos has been relatively well studied, the quantitative role of infauna in modifying critical ecosystem services such as nutrient cycling remains still poorly constrained. This stems largely from difficulties in scaling biogeochemical dynamics observed at the plot (mm - m) scale to the larger framework of coastal ecosystems. In this collaborative project, researchers at the University of Georgia and the University of Maryland?s Chesapeake Biological Laboratory will quantify small-scale dynamics of infaunal activities and their ecological interactions under controlled conditions and incorporate these data into a novel modeling approach of sediment biogeochemistry. Specifically, they will carry out a series of experimental studies to 1) determine to what extent spatial arrangement of burrows in a complex 3-dimensional domain alters sediment biogeochemistry, 2) measure species-interaction effects and feedbacks on sediment biogeochemistry, and 3) use these findings to provide guidance on sampling the intrinsically heterogeneous coastal seafloor. Laboratory experiments will be developed using sediment microcosms with artificial burrows and real organisms ? the ubiquitous Arenicola cristata and Nereis diversicolor - in separate experiments. Fluxes between the sediment and the overlying water of several diagenetically and ecologically important solutes will be measured. Burrow mimic experiments will provide detailed empirical information on burrow irrigation and spatial orientation effects on sediment-seawater exchange. This information will be used to parameterize a three-dimensional reactive transport model. Microcosms containing different combinations of the two macrofaunal species distributed in even and clustered spatial arrangements will be used to determine species interaction effects on burrow geometry and irrigation, and consequences for solute fluxes. The experimental data will elucidate the response of infauna to spatial proximity as well as the interaction across and within species. Comparison of observational data to model simulations will be used to assess the impact of macrofaunal interactions on sediment biogeochemistry. Finally, reactive transport model simulations will be performed for scenarios differing in densities and spatial arrangement of macrofauna, as well as their interactions. Aggregate fluxes across the sediment water interface will be estimated by dividing the seafloor up into tiles for which model flux estimates can be obtained. This approach will be used to evaluate various possible sampling strategies, and determine how well a limited number of flux measurements can approximate the contribution of benthic infauna to coastal biogeochemical cycles. In terms of broader impacts, this study is expected to provide a framework for scaling individual flux measurements taken in coastal sediments to larger scale mass fluxes. The findings will broaden our understanding of nutrient dynamics in the coastal ocean and benefit the general experimental community by providing context for the interpretation of flux data and design of measurement campaigns. One graduate student will be trained in experimental and numerical methodology. In addition, development of outreach materials and exhibits about sediment biogeochemistry and benthic infauna for the CBL visitor center will expose roughly 3500 visitors per year to lesser known aspects of the marine environment.

海底在浅水生态系统内的元素循环中起着至关重要的作用。尽管对沿海底栖生物进行了相对良好的研究，但Infauna在修改关键生态系统服务（例如营养循环）中的定量作用仍然受到限制。这主要源于在图（MM -M）尺度上观察到更大的沿海生态系统框架的生物地球化学动力学的困难。在这个合作项目中，佐治亚大学和马里兰州的切萨皮克大学生物实验室的研究人员将在受控条件下量化小规模的无效活动及其生态相互作用的动态，并将这些数据纳入一种新型的泥沙生物地球化学模型。具体而言，他们将进行一系列实验研究至1）确定复杂的3维领域中洞穴的空间排列在多大程度上改变了沉积物生物地球化学，2）测量物种相互作用的影响和对沉积物生物地球化学的反馈以及3）使用3）这些发现提供了有关对本质上异质沿海海底取样的指导。实验室实验将使用带有人工洞穴和真实生物的沉积物缩影开发？在单独的实验中，无处不在的竞技场和Nereis多样色。将测量沉积物和几种具有生态重要溶质的上覆的水之间的通量。洞穴模仿实验将提供有关洞穴灌溉和空间取向对沉积物 - 水交换的详细经验信息。该信息将用于参数化三维反应性传输模型。含有分布在均匀和簇的空间排列中的两个大芳族物种的不同组合的缩影将用于确定物种相互作用对洞穴几何和灌溉的影响，以及对溶质通量的后果。实验数据将阐明Infauna对空间接近性以及物种内部和内部的相互作用的响应。将观察数据与模型模拟的比较将用于评估大小相互作用对沉积物生物地球化学的影响。最后，将进行反应性传输模型模拟，以实现大小写的密度和空间排列不同及其相互作用的情况。通过将海底分为瓷砖，可以估算到沉积物水界面上的聚集通量，以获得模型通量估计。这种方法将用于评估各种可能的抽样策略，并确定有限数量的通量测量值能近似底栖ifauna对沿海生物地球化学周期的贡献。在更广泛的影响方面，这项研究有望提供一个框架，用于将沿海沉积物中的单个通量测量扩展到更大的质量通量。这些发现将扩大我们对沿海海洋中营养动态的理解，并通过为通量数据的解释和测量运动设计提供背景，从而使一般实验社区受益。一名研究生将接受实验和数值方法的培训。此外，开发有关CBL游客中心的沉积物生物地球化学和底栖Infauna的展览材料和展览将使每年大约3500名游客接触到海洋环境的鲜为人知的方面。

项目成果

期刊论文数量（4）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Burrow patchiness and oxygen fluxes in bioirrigated sediments

生物灌溉沉积物中的洞穴斑块和氧气通量

DOI：
10.1016/j.jembe.2011.11.004
发表时间：
2012
期刊：
Journal of Experimental Marine Biology and Ecology
影响因子：
2
作者：
Dornhoffer, T.;Waldbusser, G.G.;Meile, C.
通讯作者：
Meile, C.

Intermittent bioirrigation and oxygen dynamics in permeable sediments: An experimental and modeling study of three tellinid bivalves

DOI：
10.1357/002224012806770955
发表时间：
2012-11
期刊：
Journal of Marine Research
影响因子：
0.5
作者：
N. Volkenborn;C. Meile;L. Polerecky;C. Pilditch;A. Norkko;J. Norkko;J. Hewitt;S. Thrush;D. Wethey;S. Woodin
通讯作者：
N. Volkenborn;C. Meile;L. Polerecky;C. Pilditch;A. Norkko;J. Norkko;J. Hewitt;S. Thrush;D. Wethey;S. Woodin

Modeling lugworm irrigation behavior effects on sediment nitrogen cycling