Data Accompanying "Leveraging successional facilitation to improve restoration of foundational dune grasses along a frequently disturbed coastline"

Experimental Data accompanying "Leveraging successional facilitation to improve restoration of foundational dune grasses along a frequently disturbed coastline" Authors: Hallie Fischman, Copeland Cromwell, Joe Morton, Ralph Temmink, Tjisse van der Heide, Pete Adams, Christine Angelini Manuscript Abstract Coastal ecosystems provide critical storm and flood protection services, but are rapidly degrading worldwide, making their restoration urgent. Here, we evaluated whether successional facilitation, where pioneers facilitate climax species, could be leveraged to accelerate coastal dune revegetation. A survey spanning 270km of Southeast US coastline revealed that Panicum amarum (bitter panicum) supported higher plant richness than Uniola paniculata (sea oats), and that sea oat cover was 230% greater on mature dunes than disturbed dunes, suggesting bitter panicum functions as a pioneer and sea oats is a climax species. A reciprocal transplant experiment confirmed this interpretation: bitter panicum stem production and height fell by 37% and >20 cm, respectively, when planted proximate to sea oats versus in isolation, whereas sea oats produced 38% more and >12 cm taller stems when planted proximate to bitter panicum versus in isolation. A second experiment evaluating the density-dependence of this facilitative interaction revealed that sea oats transplanted into low densities of bitter panicum grew >15% taller than isolated and high-density treatments. However, within seven months, wave inundation eliminated >60% propagules in both experiments. To explore foredune inundation frequency and its implications for dune revegetation, we applied empirical wave runup models at 101 locations throughout Volusia County, Florida. While disturbance frequency varied seasonally and annually, sites with low dune crests and steep beach slopes experienced frequent inundation (>50 events/year). Given the interactions between geomorphology and vegetation success, we present decision matrix to guide managers in determining optimal revegetation methods tailored to project goals and site conditions. Methods and Data Description Experiment 1: Uniola paniculata (sea oats) and panicum amarum (bitter panicum) were planted in one of three treatments. Controls are in bare areas, Adjacent treatments (adj) are planted 50cm away from naturally occuring patches of the other species (ie, SO-adj-NPA is sea oats planted adjacent to natural bitter panicum), and Within treatments are planted in a naturally occuring patch of the other species (ie, SO-in-NPA is sea oats planted into a patch of natural bitter panicum). Each replicate consisted of 5 transplant propagules in an X configuration. At each monitoring, all stems were counted and the maximum height of each plot was measured. Plot treatments were reassigned during monitoring, if needed, such that any plot with the heterospecific growing within the 0.25 m2 area was considered a “within plot” and any plot with the heterospecific <50 cm away was considered an “adjacent plot”. See maunscript for additional details. Experiment 2: Sea oats were planted in the same configuration (5 propagules in an X) surrounded by varrying densities of natural bitter panicum. At each monitoring, we counted all bitter panicum stems within a 1m radius of the transplant, all propogule stems, and measured the height of the tallest transplant in each plot. Treatments were binned based on the number of surrounding bitter panicum stems at the final monitoring point: “Zero”, containing no stems within the 1 m radius (n=20 plots); “Low”, 1-9 stems in the surrounding 1 m radius (n=46 plots); “Mid” 10-34 stems in the 1 m radius (n=29 plots); and “High”, 35-70 stems in the 1m radius (n=25 plots). See manuscript for additional details. Datasets contains stem counts and heights of planted grasses over time. Stem counts are provided for each of the 5 propagules that comprise a single experimental unit, and a single maximum height is provided per plot. Plots were monitored approximately bimonthly until grasses were eroded by waves (see manuscript). Additional information on treatments are provided in the manuscript and data methods sections.本数据集配套于论文《利用演替促进作用改善高频扰动海岸带基础沙丘草本修复效果》（原英文标题：Leveraging successional facilitation to improve restoration of foundational dune grasses along a frequently disturbed coastline），作者为Hallie Fischman、Copeland Cromwell、Joe Morton、Ralph Temmink、Tjisse van der Heide、Pete Adams、Christine Angelini。 论文摘要 海岸生态系统提供关键的风暴与洪水防护服务，但全球范围内正快速退化，其修复工作迫在眉睫。本研究评估了演替促进作用（successional facilitation）——即先锋物种促进顶极物种定植的生态过程——是否可用于加速海岸沙丘植被恢复。一项覆盖美国东南部270公里海岸线的调查显示：苦黍（Panicum amarum）相比海燕麦（Uniola paniculata）能支撑更高的植物物种丰富度；成熟沙丘上海燕麦的盖度较受扰沙丘高出230%，这表明苦黍可作为先锋物种，而海燕麦为顶极物种。互易移植实验（reciprocal transplant experiment）验证了这一推论：当与海燕麦邻近种植时，苦黍的茎秆产量下降37%，株高降低超20厘米；而单独种植时苦黍的上述指标无显著变化。与之相对，当与苦黍邻近种植时，海燕麦的茎秆产量提升38%，株高增加超12厘米，单独种植时则无此增益。第二项评估该促进作用密度依赖性的实验显示：种植于低密度苦黍群落中的海燕麦，其株高较单独种植组与高密度组高出15%以上。但在七个月内，两项实验中均有超过60%的繁殖体（propagules）被海浪淹没清除。为探究前沙丘的淹没频率及其对沙丘植被恢复的影响，研究团队在佛罗里达州沃卢西亚县（Volusia County）的101个点位应用了经验波流增水模型（wave runup models）。尽管扰动频率随季节与年度动态变化，但沙丘脊低矮、海滩坡度较陡的点位会遭遇频繁的海浪淹没（每年超50次）。鉴于地貌与植被定植间的相互作用，本研究提出了一套决策矩阵（decision matrix），以指导管理者根据项目目标与立地条件选择最优的植被恢复方案。 方法与数据说明 实验1：海燕麦（Uniola paniculata）与苦黍（Panicum amarum）被种植于三种处理组中：对照组设置于裸地；邻近组（adj）指种植于距另一物种自然定植斑块50厘米处（例如SO-adj-NPA代表海燕麦种植于自然苦黍斑块邻近区域）；内生组指种植于另一物种的自然定植斑块内部（例如SO-in-NPA代表海燕麦种植于自然苦黍斑块内部）。每个重复单元包含5个以X型配置的移植繁殖体。每次监测时，统计所有茎秆数量并测定每个样地的最大株高。若监测过程中需要重新划分样地处理：若异种植物生长于样地0.25平方米范围内，则将该样地归为“内生样地”；若异种植物距离样地小于50厘米，则归为“邻近样地”。更多细节参见论文正文。 实验2：海燕麦以相同配置（5个繁殖体呈X型排布）种植，周围环绕不同密度的自然苦黍种群。每次监测时，统计移植样地1米半径范围内的所有苦黍茎秆数量、所有繁殖体茎秆数量，并测定每个样地内最高移植植株的株高。根据最终监测时周围苦黍茎秆的数量将处理组划分为四类：“零密度组”，1米半径范围内无苦黍茎秆（n=20个样地）；“低密度组”，1米半径范围内有1~9株苦黍（n=46个样地）；“中密度组”，1米半径范围内有10~34株苦黍（n=29个样地）；“高密度组”，1米半径范围内有35~70株苦黍（n=25个样地）。更多细节参见论文正文。 本数据集包含随时间变化的种植草本茎秆数量与株高数据。每个实验单元由5个繁殖体组成，数据提供了每个繁殖体的茎秆计数，以及每个样地的最大株高。样地约每两个月监测一次，直至草本植被被海浪侵蚀清除（详见论文）。更多处理组相关信息参见论文正文与数据方法部分。