Composite Substrates Reveal Inorganic Material Cues for Coral Larval Settlement
Composite Substrates Reveal Inorganic Material Cues for Coral Larval Settlement
复制标题
DOI：
10.1021/acssuschemeng.1c08313
复制
发表时间：
2022-03
期刊：
影响因子：
--
通讯作者：
M. Levenstein;K. L. Marhaver;Zachary A. Quinlan;Haley M. Tholen;L. Tichy;J. Yus;I. Lightcap;Linda Wegley Kelly;G. Juarez;M. Vermeij;A. W. Wagoner Johnson
中科院分区：
文献类型：
--
作者：
M. Levenstein;K. L. Marhaver;Zachary A. Quinlan;Haley M. Tholen;L. Tichy;J. Yus;I. Lightcap;Linda Wegley Kelly;G. Juarez;M. Vermeij;A. W. Wagoner Johnson
礁石珊瑚种群的广泛消失，加上珊瑚幼体的低定居率和存活率，使情况更加复杂。为了重建珊瑚群落，恢复从业者已经制定了工作流程，将脆弱的珊瑚幼虫安置在实验室，并将定居的幼体安置在自然和人工珊瑚礁上。这些工作流程通常利用自然的生化沉降线索，将这些线索呈现给游动的幼虫以诱导沉降。本文建立了潜在的无机线索来补充这些已知的生化效应。沉降基质由碳酸钙制成，碳酸钙是一种天然存在于珊瑚礁上的材料，并添加了沙子、玻璃和碱土碳酸盐等添加剂。对两种加勒比珊瑚的幼虫进行的实验表明，添加剂对沉降的偏好与体积表面的平均粗糙度和润湿性等特性无关。相反，对底物的分析表明，沉降的珊瑚幼虫可以探测到比其身体宽度小一个数量级以上的局部地形特征，并且可以感知并积极响应可溶性无机矿物，如二氧化硅（sio2）和锶矿（SrCO 3）。这些发现为珊瑚礁修复开辟了一个新的研究领域，在这个领域中，复合基质可以设计成天然有机和无机添加剂的组合，以增加幼虫的沉降，并可能改善沉降后的生长、矿化和防御。在支持信息中提供了石灰砂浆制造工艺和附加基板类型的制造以及关于基板表征方法的详细信息。幼虫沉降实验。将不同组成的试验基质一起放入1 L的重复聚苯乙烯箱中，每个箱中含有800 mL过滤海水（FSW），以评估幼虫的定居选择。FSW采用孔径分别为50、20、5和0.5 μ m的堆叠沉淀物过滤器（h2o Distributors, Marietta， GA）制备。沉降实验开始时，每个培养皿中移液200只（±5%）幼虫，7天后结束，记录每个培养皿顶部和底部的沉降位置。采用单因素方差分析和事后Tukey检验来评估数据，以确定显著性差异；更详细的统计方法见辅助资料。
: The widespread loss of stony reef-building coral populations has been compounded by the low settlement and survival of coral juveniles. To rebuild coral communities, restoration practitioners have developed work fl ows to settle vulnerable coral larvae in the laboratory and outplant settled juveniles back to natural and arti fi cial reefs. These work fl ows often make use of natural biochemical settlement cues, which are presented to swimming larvae to induce settlement. This paper establishes the potential for inorganic cues to complement these known biochemical e ff ects. Settlement substrates were fabricated from calcium carbonate, a material present naturally on reefs, and modi fi ed with additives including sands, glasses, and alkaline earth carbonates. Experiments with larvae of two Caribbean coral species revealed additive-speci fi c settlement preferences that were independent of bulk surface properties such as mean roughness and wettability. Instead, analyses of the substrates suggest that settling coral larvae can detect localized topographical features more than an order of magnitude smaller than their body width and can sense and positively respond to soluble inorganic minerals such as silica (SiO 2 ) and strontianite (SrCO 3 ). These fi ndings open a new area of research in coral reef restoration, in which composite substrates can be designed with a combination of natural organic and inorganic additives to increase larval settlement and perhaps also improve post-settlement growth, mineralization, and defense. of the lime mortar fabrication process and the fabrication of additional substrate types are provided in the Supporting Information along with details on substrate characterization methods. Larval Settlement Experiments. Test substrates with di ff erent compositions were placed together in replicate 1 L polystyrene bins, each containing 800 mL of fi ltered seawater (FSW), to evaluate larval settlement choices. FSW was prepared using a succession of stacked sediment fi lters with pore sizes of 50, 20, 5, and 0.5 μ m (H 2 O Distributors, Marietta, GA). Settlement experiments were initiated by pipetting 200 larvae ( ± 5%) into each bin and ended after 7 days by recording settlement locations on the top and bottom of each substrate. Data were evaluated by one-way ANOVA with post hoc Tukey testing to determine signi fi cance di ff erences; more detailed statistical methods are provided in the Supporting Information.