OPUS:CRS: Synthesis of decadal changes in controls, trajectories, & tipping points in vegetation cover, spatial structure, & marsh platform elevation in Great Sippewissett Marsh

盐沼是沿海环境的共同特征。它们提供基本的服务，如保持水质，稳定海岸线，并为重要的渔业提供选择栖息地。在世界各地，盐沼正受到人类活动长期影响的威胁。这些因素包括营养负荷增加、海平面上升加速以及气温和降水量增加。这些变化可能会达到临界点，超过这个临界点，这些服务可能会停止。该项目使用了一个49年的数据集盐沼反应氮添加和其他外部驱动程序，以增加对盐沼结构和功能的理解。了解盐沼对这种变化的反应对于更好地管理这些重要的生态系统是必要的。这项研究的结果将导致实质性的贡献盐沼生态学的基本问题，并将是有益的利益相关者负责湿地管理。从这项研究中产生的完整数据库将通过DataONE（地球数据观测网络）免费提供给任何未来的用户。该项目提出了一个综合的丰富数据库，该数据库来自对大Sippewissett沼泽的长期研究，这是马萨诸塞州科德角的一个代表性的新英格兰盐沼。核心数据库包括：a）高清晰度（10 × 10厘米）的植被镶嵌记录，和B）高清晰度（±1-3毫米）的微海拔空间分布，两者都是在49年前建立的10米半径的重复实验地块内测量的。这些地块受到长期处理，包括四种不同水平的营养投入，与世界河口的富营养化范围相当。在条件发生实质性变化的同时，富集仍在继续：因此，这项工作将评估暴露于广泛富营养化的盐沼如何对海平面上升、温度和降水的相互作用和平行变化作出反应。这个独一无二的数据库的综合将允许定义主要驱动变量的交互作用，促进对变化条件下盐沼响应和十年轨迹的理解，并发展对外部与内部控制，稳定状态，临界点，该奖项反映了NSF的法定使命，并通过评估被认为值得支持使用基金会的知识价值和更广泛的影响审查标准。

Salt marshes are common features of coastal environments. They provide fundamental services, such as maintaining water quality, stabilizing shorelines, and providing choice habitats for important fisheries. Across the world, salt marshes are under threat from the long-term effects of human activities. These include increased nutrient loading, accelerating sea level rise, and increased temperature and precipitation. These changes may be reaching tipping points beyond which these services may cease. This project uses a 49-year dataset on salt marsh responses to nitrogen addition and other external drivers to increase understanding of salt marsh structure and function. Knowledge about the response of salt marshes to such changes is necessary for better management of these critical ecosystems. Results from this research will lead to substantial contributions to basic questions about ecology of salt marshes and will be useful to stakeholders responsible for wetland management. The full database generated from this research will be made freely available to any future users through DataONE (Data Observation Network for Earth).The project proposes a synthesis of a rich database derived from long-term research in the Great Sippewissett Marsh, a representative New England salt marshes in Cape Cod, MA. The core database includes a) a high-definition (10x10 cm) record of a mosaic of vegetation, and b) a high-definition (±1-3 mm) spatial distribution of micro-elevations, both measured within replicated experimental 10-m radius plots established 49 years ago. These plots have been subject to chronic treatments, including four different levels of nutrient inputs, comparable to ranges of eutrophication found in the worlds’ estuaries. The enrichments continued while conditions changed substantially: this work therefore will assess how salt marshes exposed to a wide range of eutrophication will respond to interactive and parallel changes in sea level rise, temperatures, and precipitation. Synthesis of this one-of-a-kind database will allow definition of interactive effects of major driving variables, advance understanding of salt marsh responses and decadal trajectories under changing conditions, and develop theoretical understanding of external vs internal controls, stable states, tipping points, and variability of decadal vegetation trajectories.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.