The influence of biophysical coupling and cross-scale interactions on ecosystems of the Plum Island LTER

查明支配生物体地理分布的生物和环境因素，对于了解自然生态系统的功能及其给社会带来的种种好处至关重要。例如，盐沼生态系统是海陆交界处的关键过渡地带，并提供关键的生态系统服务，例如通过清除陆地径流中的过量营养物质来改善水质，以及通过海岸线缓冲来减轻海岸侵蚀。该项目利用实地调查、实验室实验和数学模型相结合的方法，预测负责这些关键生态系统服务的生物的地理分布如何受到生物相互作用(例如，竞争和捕食)以及环境因素(例如，温度和物理干扰)的影响，这些因素随着新英格兰盐沼地区的海洋流而变化。该项目的更广泛影响包括对研究生进行生物学、统计学、数学建模和计算机编程方面的交叉培训。此外，该项目的成果将与梅子岛生态系统长期生态研究(LTER)网络共享，并将被纳入生物统计学、数学建模和实验设计的本科课程，以展示定量和跨学科的STEM培训对于解决社区和生态系统生态学中的重要问题的重要性。最后，将创建多个互动网络模块，以加强这项研究成果在传统学术界之外的传播，包括东北大学的K-12推广计划。该项目的总体目标是确定理解和预测多个尺度上的多营养盐沼生态系统的动态是否取决于物理海洋过程的整合及其对异地输入供应的影响。该项目将在NSF的梅子岛LTER进行，由四个目标组成：(1)在三个嵌套空间尺度上对永久建立的研究小区进行重复调查，以量化异地输入的大小和海洋和陆地食物网的群落结构，从而评估异地输入和食物网结构的时空分布是否与其假定的物理海洋驱动因素一致；(2)在三个嵌套空间尺度上操纵碎屑输入大小的梯度以及海鱼自上而下控制的实地实验，从而能够评估观察到的调查模式是否由自下而上和自上而下的过程驱动；(3)全因素实验室实验，以进一步理清海洋鱼类和陆地蜘蛛自上而下控制在关键生态系统过程中的作用，如初级生产、分解、草食和跨碎屑输入梯度的捕食；以及(4)开发一个场参数化的空间显式数学模型，以确定自下而上强迫和自上而下控制在不同尺度上对盐沼群落结构的独立和联合影响。通过在生物物理-异地输入框架中结合模型和现场实验，该项目将利用传统上与群落生态学相关联的机械洞察力来揭示局部和广泛的过程对开放生态系统的等级组织动态的联合影响。该项目将有助于为新英格兰盐沼的资源管理提供信息，并通过强调定量和跨学科的STEM培训对解决生物学中的重要问题的重要性来促进公共教育。该项目由生物海洋学和生态系统科学集群联合资助。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Identifying the biological and environmental factors that govern the geographical distribution of organisms is critical for understanding the functioning of natural ecosystems and the myriad benefits that they provide to society. For example, salt marsh ecosystems serve as critical transition zones at the land-sea interface and provide key ecosystem services such as improving water quality via removal of excess nutrients from terrestrial run-off and mitigating coastal erosion via shoreline buffering. This project leverages a combination of field surveys, lab experiments, and mathematical models to predict how the geographical distribution of organisms responsible for these critical ecosystem services is influenced by biological interactions (e.g., competition and predation) as well as environmental factors (e.g., temperature and physical disturbance) that vary with oceanographic currents across a range of New England salt marsh locations. The broader impacts of the project include cross-training of graduate students in biology, statistics, mathematical modeling, and computer programming. In addition, the results of this project will be shared with the Plum Island Ecosystems Long Term Ecological Research (LTER) Network and will be integrated into undergraduate courses in biostatistics, mathematical modeling, and experimental design in order to demonstrate the importance of quantitative and interdisciplinary STEM training for addressing important questions in community and ecosystem ecology. Finally, multiple interactive web modules will be created to enhance the dissemination of the results of this research beyond traditional academic circles, including Northeastern University’s K-12 outreach programs.The overall aim of this project is to determine whether understanding and predicting the dynamics of multi-trophic salt marsh ecosystems across multiple scales hinges upon the integration of physical oceanographic processes and their influence on the supply of allochthonous inputs. This project will be conducted at NSF’s Plum Island LTER and consists of four objectives: (1) repeated surveys of permanently established study plots across three nested spatial scales to quantify the magnitude of allochthonous inputs and the community structure of both marine and terrestrial food webs, allowing an assessment of whether the spatiotemporal distributions of allochthonous inputs and food web architectures are consistent with their putative physical oceanographic drivers; (2) a field experiment that manipulates a gradient in the magnitude of detrital input as well as top-down control by marine fish across three nested spatial scales, enabling an assessment of whether observed survey patterns are driven by bottom-up vs. top-down processes; (3) a fully factorial lab experiment to further disentangle the role of the top-down control by marine fish vs. terrestrial spiders on key ecosystem processes such as primary production, decomposition, herbivory, and predation across a gradient of detrital inputs; and (4) development of a field-parameterized, spatially-explicit mathematical model to determine the independent and joint influences of bottom-up forcing and top-down control on the salt marsh community structure across scales. By combining models and field experiments in a biophysical-allochthonous input framework, this project will leverage the mechanistic insights traditionally associated with community ecology to reveal the joint influence of local and broad-scale processes on the hierarchically organized dynamics of open ecological systems. This project will help inform resource management for New England salt marshes and promote public education by highlighting the importance of quantitative and interdisciplinary STEM training for addressing important questions in biology.This project is jointly funded by Biological Oceanography and the Ecosystems Science Cluster.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.