COLLABORATIVE RESEARCH: RAPID 2017 Hurricane Irma: How do the effects of pulse disturbance vary with abiotic conditions, disturbance history, and proximity to a transition zone.

风暴潮通常被认为是与飓风有关的对生命和财产的最大威胁。风暴潮对生态系统影响的研究通常集中在暴露的沿海地区，如海滩。然而，向上游输送盐水可能会产生长期影响，并可能导致宝贵的淡水潮汐区减少，这些淡水潮汐区为鱼类和野生动物提供栖息地，保护和改善水质，并储存洪水。这一点尤其重要，因为由于海平面上升，这些地区已经面临着上游盐水入侵的潜在损失。2017年9月11日，飓风“厄玛”经过美国，在乔治亚州中部海岸引发了有史以来最高的风暴潮，导致海水比平时向上游移动得更远。美国国家科学基金会（nsf）赞助的乔治亚州海岸生态系统长期生态研究项目（GCE-LTER）有长期的实验和监测项目，提供“之前”的数据和了解这次事件影响的背景。研究人员预计，风暴潮带来的盐水将影响潮间带湿地生态系统的多个组成部分，包括植物、动物、水化学和土壤表面海拔。这项研究的结果将通过佐治亚州海岸研究委员会和佐治亚州海岸灾害实践社区与沿海管理人员分享。LTER研究人员还将接待K-12教师，作为GCE校园项目的一部分，并与他们合作，将这种经验运用到课堂上。理解像飓风厄玛这样的扰动的影响是很困难的，因为它们很难通过实验来控制，而且在不同的地区会产生不同的影响。研究人员推测：1)风暴潮对上游地区的影响比下游地区更大，潮点的影响最大，恢复时间最长；2)从历史上看，以前接触过海水的地区将显示出更大的影响；3)在不同湿地生境之间的边界地区（即盐沼和微咸沼泽植物之间的边缘），变化更有可能发生。他们将通过以下方法来检验这些假设：1)增加GCE-LTER湿地监测点的采样，这些监测点分布在乔治亚州中部海岸并向内陆延伸；2)利用正在进行的GCE-LTER现场实验来确定先前的盐水干扰处理如何影响对飓风风暴潮的响应；3)收集航空图像，这将使他们能够看到与风暴前的地图相比，植被类型的景观水平变化，并在预先建立的过渡地块上进行额外的采样。LTER的研究人员推测，像这次风暴这样罕见但严重的事件是重新设置这些宝贵的潮间带湿地栖息地分布的主要原因。

Storm surge is often considered the greatest threat to life and property associated with a hurricane. Studies of the ecosystem effects of storm surge often focus on exposed coastal areas such as beaches. However, the upstream delivery of salt water can have long-lasting effects and can result in the decline of valuable freshwater tidal areas, which provide habitat to fish and wildlife, protect and improve water quality, and store floodwaters. This is especially important given the fact that these areas are already facing potential loss due to upstream salt water intrusion as a result of sea level rise. Hurricane Irma, which passed over the US on Sept. 11, 2017, caused the highest storm surge ever recorded on the central Georgia coast and resulted in salt water moving much further upstream than usual. The NSF-sponsored Georgia Coastal Ecosystems Long Term Ecological Research Project (GCE-LTER) has long-term experiments and monitoring programs that provide "before" data and a context for understanding the effects of this event. The investigators anticipate that the salt water delivered by the storm surge will affect multiple components of intertidal wetland ecosystems, including plants, animals, water chemistry, and soil surface elevation. The results of this research will be shared with coastal managers through the Georgia Coastal Research Council and the Georgia Coastal Hazards Community of Practice. The LTER researchers will also host K-12 teachers as part of the GCE Schoolyard Program and work with them to use this experience in the classroom.Understanding the effects of disturbances like Hurricane Irma is difficult because they are hard to manipulate experimentally and can act differently on different parts of the landscape. The investigators hypothesize that: 1) the effects of the storm surge will be greater in upstream as opposed to downstream areas, with the greatest effects and longest recovery times in tidal fresh sites; 2) areas that have had previous exposure to salt water will show greater effects based on their history; and 3) changes will be more likely in areas that are at the borders between different wetland habitats (i.e. the edge between salt marsh and brackish marsh plants). They will test these hypotheses by 1) augmenting sampling of the GCE-LTER wetland monitoring sites, which are distributed along and extend inland from the central Georgia Coast; 2) taking advantage of an ongoing GCE-LTER field experiment to determine how prior saline disturbance treatments affect responses to the hurricane storm surge; and 3) collecting aerial imagery that will allow them to look at landscape level shifts in vegetation type compared to pre-storm maps, and doing additional sampling in pre-established transitional plots. The LTER researchers speculate that rare but severe events like this storm are the major occasions that re-set the distribution of habitats in these valuable intertidal wetlands.