GROW Tile ms data

Eastern oyster recruitment and size on Oyster Castles (OC) and GROW Reef Tiles (GT) were assessed three times over 25 months in multiple locations with varying salinity. Four sites in the Chesapeake Bay region were examined: Cherrystone Inlet, Mockhorn Bay (eastern shore), Elizabeth River and, Lynnhaven Bay (western shore). Our hypothesis was that GROW Tiles would allow for higher oyster densities and larger oysters than the Oyster Castles due to habitat heterogeneity (varied orientation of the surfaces) and their special composition with concrete that is formulated to match oyster shell (GROW 2021). Additionally, we hypothesized that oyster densities would differ among sites due to abiotic stressors such as salinity, relative shoreline height, wave exposure. At each site, ten OC and ten GT were randomly placed parallel to shore in the intertidal zone in May 2019. Sites were sampled non-destructively in October 2019, July 2020, and June 2021. A quadrat (0.30 m x 0.30 m) was placed on top the structure, dividing the structure into four quadrants, and one random quadrant was chosen to count and measure oysters for shell height and mortality status. Data on oyster height and mortality status for each of the sites and years are shown in the dataset columns. Data from each year and combined data (2019-2021) were analyzed using the response variables oyster density and shell height along with combinations of the factors year, site, and substrate type. Both substrate types (OC and GT) had high oyster recruitment (>400 oysters m-2). At 25 months post-deployment, mean oyster densities differed significantly by substrate, with 553.3 ± 59.8 (SE) oysters m-2 on OC and 423.0 ± 57.0 oysters m-2 on GT (24% higher on OC), associated with 27% higher surface area on OC. Oyster densities differed by site, with highest densities in Mockhorn Bay. Growth was ~60-70 mm over the 25 months, and oysters were smallest at the highest-salinity and highest-density site. Mean oyster shell height was greater on GT (61.7 ± 2.2 mm) compared to OC (57.3 ± 2.1) over the time frame.本研究针对牡蛎城堡（Oyster Castles，OC）与GROW礁体砖（GROW Reef Tiles，GT）上的东方牡蛎（Eastern oyster）幼体补充量与个体规格，在25个月内于多个盐度梯度区域开展了三次评估。研究覆盖切萨皮克湾（Chesapeake Bay）区域的四个采样点：切里斯顿湾入口（Cherrystone Inlet）、莫克霍恩湾（Mockhorn Bay，东岸）、伊丽莎白河（Elizabeth River）以及林恩黑文湾（Lynnhaven Bay，西岸）。本研究提出两项核心假设：其一，相较于牡蛎城堡，GROW礁体砖凭借生境异质性（表面朝向多样化）以及适配牡蛎壳的专用混凝土配方（GROW，2021），可支撑更高的牡蛎种群密度与更大的个体规格；其二，不同采样点的牡蛎种群密度会因盐度、岸线相对高度、波浪暴露等非生物胁迫因子存在显著差异。2019年5月，于每个采样点的潮间带区域随机平行于岸线布设10组牡蛎城堡与10组GROW礁体砖。分别于2019年10月、2020年7月及2021年6月对各采样点开展非破坏性采样。采样时于样体顶部放置0.30 m×0.30 m的样方框，将样体划分为四个象限，随后随机选取其中一个象限计数并测量牡蛎的壳高与存活状态。各采样点与各年份的牡蛎壳高及存活状态数据均收录于数据集的对应列中。本研究以牡蛎种群密度与壳高作为响应变量，结合年份、采样点及基底类型三类因子的组合，分别对单年份数据与2019-2021年合并数据开展统计分析。两类基底（OC与GT）均实现了较高的牡蛎幼体补充量（>400 只·m⁻²）。布设完成25个月后，不同基底的牡蛎平均种群密度存在显著差异：牡蛎城堡组的密度为553.3±59.8（标准误）只·m⁻²，GROW礁体砖组为423.0±57.0只·m⁻²（牡蛎城堡组密度高出24%），这一差异与牡蛎城堡的表面积高出27%相关。不同采样点的牡蛎种群密度亦存在显著差异，其中莫克霍恩湾的种群密度最高。25个月内牡蛎的生长量约为60~70 mm，且在盐度最高、种群密度最大的采样点中，牡蛎个体规格最小。整个实验周期内，GROW礁体砖组的牡蛎平均壳高（61.7±2.2 mm）显著高于牡蛎城堡组（57.3±2.1 mm）。