Symbiodiniaceae ITS2 sequences from reef corals in St. John, U.S. Virgin Islands

Monitoring coral cover can describe the ecology of reef degradation, but rarely can it reveal the proximal mechanisms of change, or achieve its full potential in informing conservation actions. Describing temporal variation in Symbiodiniaceae within corals can help address these limitations, but this is rarely a research priority. Here, we augmented an ecological time series of the coral reefs of St. John, US Virgin Islands, by describing the genetic complement of symbiotic algae in common corals. Seventy-five corals from 9 species were marked and sampled in 2017, and following hurricanes in September 2017, 41% were sampled in 2018, and 72% in 2019; 28% could not be found and were assumed to have died. Symbiodiniaceae ITS2 sequencing identified 525 distinct sequences (comprising 42 ITS2 type profiles), and symbiont diversity differed among host species and individuals, but was in most cases preserved within hosts over 3 yrs that were marked by physical disturbances from major hurricanes..., Project design and field sampling
In the summer of 2017, nine scleractinian species (Table 1) from six genera were selected based on their high abundance and ecological importance. A total of 75 coral colonies were sampled from 7–10 m depth at White Point, East Tektite, and Cabritte Horn [Fig. S1]), where the reefs have been monitored since 1992 (Edmunds 2018). Colonies were haphazardly selected along 40-m transects at each monitoring site (Edmunds 2018) between 27 July and 7 August 2017, and their positions were identified using cartesian coordinates. They were selected based on ease of location, and size (> 20-cm diameter to support multiple samplings), and marked with aluminum tags epoxied to the substratum. Following tagging, a tissue biopsy (< 1-cm diameter) was removed from the upper surface of each colony using stainless steel clippers. Samples were placed in Whirl-Pak bags and processed within 2 hours of sampling.
We searched for the tagged colonies in 2018 (13–15 August),..., , # Symbiodiniaceae ITS2 sequences from reef corals in St. John, U.S. Virgin Islands

[https://doi.org/10.5061/dryad.02v6wwq95](https://doi.org/10.5061/dryad.02v6wwq95)

Seventy-five corals from 9 species were marked and sampled in 2017, and following hurricanes in September 2017, 41% were sampled in 2018, and 72% in 2019; 28% could not be found and were assumed to have died. Symbiodiniaceae ITS2 sequencing identified 525 distinct sequences (comprising 42 ITS2 type profiles), and symbiont diversity differed among host species and individuals, but was in most cases preserved within hosts over 3 yrs that were marked by physical disturbances from major hurricanes and the onset of stony coral tissue loss disease. While changes in symbiont communities were slight and stochastic over time within colonies, variation in the dominant symbionts among colonies was observed for all host species. This data archive contains the raw ITS2 sequencing data for all corals. Processed data and subsequent anal...

监测珊瑚覆盖度可反映珊瑚礁退化的生态态势，但极少能揭示其变化的近端机制，亦无法充分发挥指导保护行动的全部潜力。解析珊瑚体内虫黄藻（Symbiodiniaceae）的时间动态，有助于弥补上述局限，但此类研究往往未被列为优先研究方向。本研究对美属维尔京群岛圣约翰岛的珊瑚礁生态时间序列进行了扩充，通过解析常见珊瑚中共生藻类的遗传组成完成这一目标。2017年，研究人员标记并采样了9个物种的75株珊瑚；2017年9月飓风过境后，2018年对其中41%的个体完成采样，2019年采样比例达72%；另有28%的个体未被寻获，推测已死亡。通过虫黄藻ITS2测序，共鉴定出525条独特序列（涵盖42个ITS2型谱）；共生体多样性在宿主物种与个体间存在差异，但在经历强飓风物理扰动的3年监测期内，多数宿主体内的共生体多样性总体保持稳定……
# 项目设计与野外采样
2017年夏季，研究人员基于高丰度与生态重要性，选取了6个属的9种石珊瑚（表1）。采样点设于怀特角（White Point）、特克蒂特东滩（East Tektite）与卡布里特角（Cabritte Horn）的7–10米水深区域（图S1），该区域的珊瑚礁自1992年起便纳入长期监测体系（Edmunds 2018）。2017年7月27日至8月7日期间，研究人员在各监测点的40米样带上随机选取珊瑚群落，通过笛卡尔坐标标记其空间位置。所选个体需便于定位，且直径大于20厘米以支持多次采样，随后用环氧树脂固定于基底的铝制标签进行标记。标记完成后，使用不锈钢剪从每个群落的上部表面获取直径小于1厘米的组织活检样本。样本被装入Whirl-Pak采样袋，并于采样后2小时内完成预处理。
2018年8月13–15日，研究人员对已标记的珊瑚群落开展搜寻……
# 美属维尔京群岛圣约翰岛礁珊瑚的虫黄藻ITS2序列数据
[https://doi.org/10.5061/dryad.02v6wwq95](https://doi.org/10.5061/dryad.02v6wwq95)
2017年，研究人员标记并采样了9个物种的75株珊瑚；2017年9月飓风过境后，2018年对其中41%的个体完成采样，2019年采样比例达72%；另有28%的个体未被寻获，推测已死亡。通过虫黄藻ITS2测序，共鉴定出525条独特序列（涵盖42个ITS2型谱）；共生体多样性在宿主物种与个体间存在差异，但在经历强飓风物理扰动以及石珊瑚组织损失病暴发的3年监测期内，多数宿主体内的共生体多样性总体保持稳定。尽管单个珊瑚群落内的共生体群落随时间呈现微弱且随机的变化，但所有宿主物种的群落间均观察到了优势共生体的变异。本数据集归档了所有珊瑚的ITS2测序原始数据。已处理的数据与后续分析……