称为珊瑚方舟的系泊中水测地线结构提供了一个模块化、可扩展和垂直可调的研究平台,可用于在以前无法操作的区域(包括近海)建造、监测和扰乱珊瑚礁群落。
当珊瑚礁支持多级营养结构并在有利的水质条件下生长时,珊瑚礁会茁壮成长并提供最大的生态系统服务,包括高光照水平、快速水流和低营养水平。近几十年来,水质差和其他人为压力因素导致珊瑚死亡,导致许多珊瑚礁的营养降级和生物复杂性的丧失。扭转营养降级原因的解决方案仍然难以捉摸,部分原因是恢复珊瑚礁的努力往往是在最初导致珊瑚死亡的相同减少条件下尝试的。
珊瑚方舟,正浮力,中水结构,旨在为易位和自然招募的珊瑚提供更好的水质条件和支持性隐秘生物多样性,以组装健康的珊瑚礁中观物,用作长期研究平台。自主珊瑚礁监测结构(ARMS)是被动沉降装置,用于将神秘的珊瑚礁生物多样性转移到珊瑚方舟,从而为自然补充提供“促进”,并为珊瑚健康提供生态支持。我们对方舟的两种设计进行了建模和实验测试,以评估结构的阻力特性,并根据它们对流体动力的响应评估它们在中水的长期稳定性。
然后,我们在两个加勒比珊瑚礁地点安装了两种方舟结构设计,并随着时间的推移测量了与方舟环境相关的几个水质指标。在部署时和6个月后,珊瑚方舟显示出增强的珊瑚礁功能指标,包括更高的流量,光和溶解氧,易位珊瑚的更高存活率,以及相对于附近相同深度的海底站点减少的沉积和微生物化。这种方法为研究人员提供了一个适应性强的长期平台,用于建立珊瑚礁群落,通过改变深度和地点等部署参数来调整当地的水质条件。
在全球范围内,珊瑚礁生态系统正在经历从高生物多样性、以珊瑚为主的底栖群落向以草皮和肉质大型藻类为主的低多样性群落的过渡1,2,3。几十年来在描述珊瑚礁退化机制方面取得的进展揭示了微生物和大型生物群落之间的联系如何加快了这些转变的速度和严重程度。例如,人类对珊瑚礁的过度捕捞引发了营养级联,其中来自未放牧藻类的过量光合作用衍生糖将能量分流到珊瑚礁微生物群落中,从而推动发病机制并导致珊瑚衰退4,5,6。由于水质下降导致珊瑚礁生物多样性的丧失,加剧了这种营养降级7,8。中宇宙水平的实验可用于通过增强生物多样性和改善水质来更好地了解和减轻珊瑚礁群落的营养降级,但后勤挑战使这些研究难以就地实施。
珊瑚礁营养降级的后果是神秘生物多样性的广泛丧失,其中大部分仍未表征7,9。珊瑚依赖于各种神秘的珊瑚礁生物(“隐生物群”),通过在捕食者防御10,清洁11,放牧竞争藻类12,13和珊瑚礁水化学调节14,15中发挥不可或缺的作用来支持它们的健康。直到最近,由于目视调查的方法限制,珊瑚礁隐生物群在珊瑚礁生态学的背景下代表性不足,知之甚少,因此在恢复或重建珊瑚礁的努力中很少考虑它们。在过去的十年中,使用称为自主珊瑚礁监测结构(ARMS)的标准化定居单元与高通量测序方法相结合,可以更好地收集和表征珊瑚礁隐生物群16,17。ARMS被动地招募了几乎所有已知珊瑚礁生物多样性的代表,并帮助揭示了神秘生物在珊瑚礁规模过程中的许多功能作用9,18,19,20,21,22,23。因此,这些定居单位提供了一种机制,将神秘的珊瑚礁生物群与珊瑚一起转移,以便通过生物介导的机制(如放牧、防御和改善当地水质)聚集更完整的珊瑚礁群落,这对于维持营养结构至关重要。
以珊瑚为主的珊瑚礁在高光照、低营养和含氧良好的环境中茁壮成长。城市化、农业和过度捕捞等人类活动通过增加径流中的沉积物、营养物质、金属和其他化合物来降低许多珊瑚礁的水质24,25,并改变生物地球化学循环26。反过来,这些活动通过窒息,能量消耗,与沉积相关的污染物的输送27,28,促进与珊瑚竞争的大型藻类的生长29,增加微生物病原体的丰度6,30,31以及创造杀死神秘无脊椎动物的缺氧区来降解珊瑚礁群落32,33.海洋条件的区域和全球变化加剧了这些和其他“局部影响”,包括温度升高和pH值降低,进一步恶化了珊瑚和其他珊瑚礁生物的状况34,35。具体而言,在底栖-水界面,底栖生物群落的呼吸和光合动力学导致pH值和溶解氧的波动,在高度退化的珊瑚礁上变得更加明显,从而创造了底栖无脊椎动物无法忍受的条件32,36,37,38.因此,提供适当的水质条件对于组建功能正常的珊瑚礁群落至关重要,但这仍然具有挑战性,因为越来越多的珊瑚礁陷入各种退化状态。
底栖生物的珊瑚和基础隐秘分类群面临的许多挑战可以通过搬迁到中水来克服,这里定义为海洋表面和海底之间的水柱设置。在中水环境中,水质改善39,40,沉积减少,与海底的距离抑制了与底栖代谢相关的参数的波动。这些特征通过向近海移动而得到进一步改善,在近海,陆上人为影响,如陆地衍生的径流,随着与海岸的距离而日益稀释。在这里,我们介绍并提供建造,部署和监测珊瑚礁方舟的协议,这种方法利用改善的中水水质条件,并在锚定的,正浮力结构上结合神秘的生物多样性,用于珊瑚礁群落的组装。
珊瑚礁方舟系统或“方舟”由两个主要组成部分组成:(1)悬挂在底栖生物上方的刚性测地平台和(2)生物覆盖或“播种”的ARMS,从附近的底栖地区转移珊瑚礁隐生物群,从而补充自然补充过程,为易位珊瑚提供更多样化和功能性的珊瑚礁群落。选择测地线结构以最大限度地提高强度并最小化建筑材料(从而减轻重量),并创建类似于珊瑚礁矩阵的内部湍流环境。
在两个加勒比海野外地点成功安装了两种设计的方舟,目前正在用于研究珊瑚礁群落的建立和生态演替(图1)。珊瑚方舟结构旨在成为长期研究平台,因此,本手稿的主要重点是描述定位、安装、监测和维护这些结构的协议,以最大限度地提高它们在中水环境中的稳定性和寿命。建模和水中测试相结合,评估结构的阻力特性,并调整设计以承受预期的流体动力。安装后,通过主动易位(珊瑚和播种ARMS单位)和自然补充相结合,在方舟和附近相同深度的底栖控制点建立了珊瑚礁群落。在整个演替早期的几个时间点记录了方舟上的水质条件、微生物群落动态和珊瑚存活情况,并与底栖控制地点进行了比较。迄今为止,与中水珊瑚方舟环境相关的条件相对于相同深度的邻近底栖控制点,对珊瑚及其相关的神秘联盟一直更有利。下面的方法描述了复制珊瑚方舟方法所需的步骤,包括如何选择地点以及设计和部署珊瑚方舟结构。监测珊瑚方舟的建议方法包含在 补充文件1中。
上述代表性结果表明,珊瑚方舟为在稳定的原位研究平台上组装珊瑚礁群落提供了栖息地和改善的水质条件。相同深度的方舟和海底控制点显示出一致的不同水质剖面。较高的平均水流速度和离海岸更远的距离减少了方舟地点中水环境中的沉积和浑浊(图6B),这可能导致方舟上测量的溶解有机碳浓度较低(图6F)。此外,水透明度的这些改善导致方舟上相对于对照地点的日间光强度升高(图6A)。与底栖生物相比,溶解氧的DIEL波动较低,表明方舟上珊瑚的氧气可用性有所改善,尤其是在夜间(图6G)。在过去的工作中,这些指标都与珊瑚存活率42,生长43,44,45和从压力中恢复46,47的改善有关,并且可能与与底栖控制地点相比,转移到方舟的珊瑚的生存结果增强有关(图8).即使在通过生物淤积积累大量生物质之后,这些条件仍然存在,这一事实表明,自然补充过程不会削弱中水环境的水质特征的改善。方舟部署在底栖控制地点离岸3公里处,可能受益于陆地衍生的沉积物、营养物质以及可能挑战近岸地点的捕捞压力的减少。在水源清洁且人类影响较小的地区(如近海)放置方舟可能比受影响严重的沿海地区提供更好的环境,以传播珊瑚礁生物多样性以进行中宇宙级实验。
初步发现还表明,中水方舟经历了较少的微生物化,这是与底栖礁栖息地退化相关的中央珊瑚礁过程4,48。高营养投入和过度捕捞已被确定为珊瑚礁营养反馈回路的驱动因素,其中能量不稳定的微生物群落增殖,导致呼吸吸收代谢可用的氧气和底栖生物珊瑚病原体的发生率增加6,49,50,51.微生物化珊瑚礁上游离病毒的丰度减少,这是微生物群落生长的主要裂解控制,表明营养结构的破坏有利于微生物进一步扩张52。与海底地点相比,方舟上的水柱相关微生物既不丰富(图7B),而且物理上更小(图7D)。方舟还显示出更高的病毒与微生物比率(图7A),游离病毒丰度(图7C)和溶解氧可用性,特别是在夜间(图6G)。综上所述,这些发现表明,相对于海底地点,中水环境显示出微生物化的可能性较小。方舟作为中层动物,只需在水柱中垂直调整即可改变环境条件,为减轻和进一步探索珊瑚礁退化的微生物和分子机制提供了机会。
这里介绍的珊瑚方舟的设计选择了两种不同频率的测地线球体(图1)。测地线频率(1V、2V、3V)表示测地线球体中重复子元素的数量,频率越高,三角形子元素的数量就越多。从结构的角度来看,测地线多面体在整个结构中分布机械应力,从而为其尺寸 53,54 带来很高的先天强度。这些特性提供了高耐用性和使用寿命,但代价是更高的流体动力阻力,这可能导致系泊系统上的负载增加。从栖息地的角度来看,方舟系统产生的阻力代表了结构内动量扩散的指标,因此代表了内部环境流量减少的程度。建模和实验验证的结果表明,由于结构内部产生湍流,“壳牌”方舟内部的流速相对于周围流场降低了40%-70%(见补充文件1的第6节)。虽然内部流量减少的最佳水平尚不清楚(并且因测地线频率而异),但结构内流量减少的区域对于创建生态位栖息地很重要 55,56、再矿化养分57,58 以及促进幼虫的保留和沉降 59,60.一般来说,更大和更高频率的测地线结构,特别是在更暴露的安装地点,需要具有更高保持力和更多冗余的锚固系统纳入结构设计。
对“壳牌”方舟系泊系统上的张力阻力分量进行现场测量的结果与建模和实验拖曳估计的结果非常吻合(图4),并且完全在预期的设计范围内。这些结果表明,流体动力学模型的假设是有效的,并且该模型可以预测背景电流范围内的阻力。然而,虽然建模和实验数据的偏差很小,但测试期间的流量范围(典型的环境、非风暴流动速度)无法在整个建模范围内进行严格的验证。在预测珊瑚方舟系统的设计要求时,建模工作应与计划部署地点的风暴频率和暴露信息相结合,以设计能够在预期的流体动力下生存的结构和系泊系统。这里介绍的建模工作可用于在其他站点以最小的输入(部署站点所需的 Ark 尺寸、频率和平均电流速度)设计方舟系统,方法是在系泊和锚固系统上提供阻力系数和最大预期力。
方舟和 ARMS 系统是模块化的,可以以与此处描述的不同规模和替代材料建造。虽然它们的最终寿命尚未确定,但珊瑚方舟的设计寿命约为10年。Arks和ARMS的材料成分会影响结构的寿命,系统的重量,因此会影响抵消重量所需的浮力,并可能影响早期结垢群落的反应(补充文件1-图S7)。例如,石灰石为ARMS上的生物定植提供了更天然的基质,并且在大多数碳酸盐礁岛屿上很容易且廉价地采购,但它比PVC和玻璃纤维等其他材料更脆弱,更重。在设计最能满足所需项目成果的 ARMS、Arks 和系泊系统时,应根据特定场地的特征考虑这些因素。
珊瑚方舟的部署地点也应根据预期的项目目标(即研究、缓解或恢复)进行选择。选址需要考虑的因素包括材料的获取、珊瑚礁状态或条件、社区投资/参与、资源限制、机构支持和许可要求。珊瑚方舟可以提供机会,以满足以下地点的特定需求:(1)包含状况相对较差的活珊瑚礁,并将受益于恢复活动,以加强珊瑚补充,珊瑚覆盖,海岸保护或人类食物资源;(2)需要将珊瑚转移到另一个地点,例如,当法律要求将活珊瑚从预定清除的碎片物品上移走时,可能会发生这种情况(在这些地点,珊瑚方舟可以与现有的恢复和移栽工作合作使用,或支持现有的恢复和移栽工作,以改善易位结果);(3)要求研究利用珊瑚方舟的新型保护和恢复技术,以提高当地努力的成功率;或(4)具有足够不同的当地条件(即不同程度的人为影响),这意味着标准化的中观生物可以对珊瑚礁过程和干预措施进行有意义的比较。监测珊瑚方舟生态系统方面(如生物生长、多样性和水化学)的具体方法将根据项目目标和特定地点的变量因项目而异。补充文件1的第5节提供了迄今为止对珊瑚方舟进行的科学监测的代表性大纲。
珊瑚方舟结构的设计可以容纳几乎任何物种、大小和年龄的珊瑚,并且应该提供相对于受干扰的珊瑚礁底栖生物的改善条件。根据在给定系统上观察到的生长和钙化速率,可能需要在方舟结构上增加正浮力以补偿生物生长并降低下沉风险。可以使用张力/压缩称重传感器或应变片对正浮力的中水结构进行称重,以确定群落的水中重量是否在增加(图5)。使用称重传感器的定期或长期测量可以补充其他更精细分辨率的珊瑚生长指标,以生成社区级生长/钙化的指标,并已作为常规维护任务包括在内,以确定系统是否有足够的正浮力来补偿这种生物生长随着时间的推移。如果已安装的方舟无法再被监测或维护,可以将其重新定位和/或移除浮力,以使方舟牢固地附着在底栖生物上。
这里描述的方法为研究人员提供了一个多功能工具包,用于组装中水礁群落,这些珊瑚礁群落可以位于水质改善的位置。通过改变方舟结构的深度或位置,水质参数的变化可以通过实验与珊瑚礁群落结构和演替轨迹的变化联系起来。这种设计特征使研究人员能够利用中水环境中丰富且未充分利用的空间来组装和研究珊瑚礁中观。使用播种的ARMS转移隐秘的生物多样性,并“促进”流动放牧无脊椎动物的自然补充,为减少藻类生物污染以及珊瑚的底栖竞争提供了一种功能性解决方案。使用已建立和标准化的采样结构作为该系统的组成部分,通过对方舟上的神秘群落进行长期监测,并与使用ARMS作为全球生物多样性普查工具生成的数据集进行比较,从而提供附加值。
珊瑚方舟可以作为一个更全面、更综合和自我调节的平台,用于繁殖珊瑚和无脊椎动物生物量,然后可以将其迁移到附近退化的珊瑚礁,并为珊瑚在改善的水质条件下生长和繁殖提供安全的避风港。正如目前在波多黎各所证明的那样,方舟可以改善缓解项目的生存结果,这些项目涉及将珊瑚和珊瑚礁生物多样性从碎片物品或退化地区重新安置。方舟在长期项目中具有相关性,可以替代鱼类种群的栖息地,测试新的保护策略,并保护原生珊瑚礁生物多样性。在此过程中,Arks为进行珊瑚礁组装和生态演替的 原位 研究提供了多功能工具,并可能对珊瑚礁连通性产生新的见解。
The authors have nothing to disclose.
我们感谢Mark Vermeij,Kristen Marhaver和库拉索岛的CARMABI研究基金会为该项目提供资源,支持和见解。我们感谢NAVFAC大西洋别克斯岛恢复方案和Jacobs工程团队在别克斯岛珊瑚方舟的安装、维护和监测方面提供的大量后勤和技术支持。我们也感谢Mike Anghera,Toni Luque,Cynthia Silveira,Natascha Varona,Andres Sanchez-Quinto,Lars ter Horst和Ben Darby在该领域的帮助和建设性投入。这项研究由FLR 的戈登和贝蒂摩尔基金会水生共生研究者奖和国防部环境安全技术认证计划(RC20-5175)资助。
PVC ARMS | |||
316 Stainless Steel Hex Head Bolt, Partially Threaded, 8" length, 1/4"-20 Thread Size | McMaster Carr | 92186A569 | Bolts for PVC ARMS assembly Per unit: 4x |
316 Stainless Steel Hex Nut, Super-Corrosion-Resistant, 1/4"-20 Thread Size | McMaster Carr | 94805A029 | Nuts for PVC ARMS assembly Per unit: 8x |
316 Stainless Steel Nylon-Insert Locknut, Super-Corrosion-Resistant, 1/4"-20 Thread Size | McMaster Carr | 90715A125 | Locknuts for PVC ARMS assembly Per unit: 4x |
316 Stainless Steel Washer for 1/4" Screw Size, 0.281" ID, 0.625" OD | McMaster Carr | 90107A029 | Washers for PVC ARMS assembly Per unit: 8x |
Nylon Unthreaded Spacers – 1/2" Long, 1/2" OD, Black | McMaster Carr | 90176A159 | Nylon spacers for PVC ARMS assembly Per unit: 20x |
PVC Sheet Type 1, 0.25" Thick, Gray | McMaster Carr | 8747K215 | PVC for ARMS stacking plates. See Supplemental File 1-Figure SI 4. Per unit: 9x Refers to drawing: Yes |
PVC Sheet Type 1, 0.5" Thick, Gray | McMaster Carr | 8747K217 | PVC for ARMS baseplates. See Supplemental File 1-Figure SI 1. Per unit: 1x Refers to drawing: Yes |
PVC Sheet Type 1, 0.5" Thick, Gray | McMaster Carr | 8747K217 | PVC for ARMS long cross spacers. See Supplemental File 1-Figure SI 2. Per unit: 4x Refers to drawing: Yes |
PVC Sheet Type 1, 0.5" Thick, Gray | McMaster Carr | 8747K217 | PVC for ARMS short cross spacers. See Supplemental File 1-Figure SI 3. Per unit: 8x Refers to drawing: Yes |
Ratcheting Combination Wrench, 7/16" | McMaster Carr | 5163A15 | Wrenches to secure PVC ARMS hardware Per unit: 2x |
Rebar, 3-ft Lengths, 1/2" Thick | McMaster Carr | 7480N115 | Rebar stakes to secure PVC ARMS to benthos. Mallet required. Per unit: 4x |
Sequentially Numbered Metal Tags | McMaster Carr | 2208N349 | Numbered tags for ARMS ID Per unit: 1x |
Limestone ARMS | |||
DeWalt Wet Tile Saw | Home Depot | D24000S | Cut limestone tile into stackable pieces Per unit: 1x |
Lift Bag, 50 lb Capacity | Amazon | B07GCNGRDR | Lift bag for transport of Limestone ARMS to benthos Per unit: 1x |
Milk Crate, Heavy Duty, 13" x 19" x 11" | Amazon | B06XGBDJMD | Crate for transport of Limestone ARMS to benthos Per unit: 1x |
Natural Limestone or Travertine Tile (Unfilled) – 12" x 12" | Bedrosians Tile & Stone | TRVSIENA1212T | Base material for Limestone ARMS layers and stacking pieces. See Supplemental File 1-Figure SI 7 and Figure SI 8. Per unit: 10x Refers to drawing: Yes |
PC-11 Epoxy Adhesive Paste, Two-Part Marine Grade | Amazon | B008DZ1864 | Two-part epoxy for Limestone ARMS assembly |
Shell Ark | |||
Downline: 1" Nylon, 6' length thimble-to-thimble with stainless sailmaker thimble at top, heavy duty galvanized thimble at bottom | West Marine | Custom | Nylon mooring line for attaching Ark mooring bridle to anchor system. Per unit: 1 |
Main structure: 105-B Epoxy | West Marine (made by West System) | 318352 | Epoxy to seal foam in struts. |
Main structure: 205-B Hardener | West Marine (made by West System) | 318378 | Epoxy to seal foam in struts. |
Mooring bridle: 3-1/8" X 2" small diamond base padeye with 7/8" bail | West Marine (Made by Harken) | 130560 | Padeyes for attaching mooring system to Ark base. Per unit: 5 |
Main structure: 3/4" H-80 Divinycell Closed-Cell Foam, Plain Sheet 48" x 96" | Fiberglass Supply | L18-1110 | Buoyant foam for struts. Cut foam into 1.5" wide strips, 15.5" long for S1 struts and 19" long for S2 struts, add to struts. Per unit: 120 |
Downline: 3/4" Stainless Masterlink | Lift-It (Made by Suncor) | S0652-0020 | Masterlink, connects top of swivel to lower portion of 5-point mooring bridle. Per unit: 1 |
Mooring bridle: 3/8" Stainless Long D Shackles with Captive Self-Locking Pin | West Marine (Made by Wichard) | 116293 | High-strength shackles to connect pad eyes to mooring system. Per unit: 5 |
Main structure: 316 SS, Pan Head Phillips Screw, 1/4-20, 3" Long | McMaster Carr | 91735A385 | Bolts to attach hull anodes to stainless struts Per unit: 2 |
ARMS attachments: 316 Stainless Steel Nylon-Insert Locknut, Super-Corrosion-Resistant, 1/2"-13 Thread Size | McMaster | 90715A165 | Locknuts for attaching ARMS to ARMS mounting baseplates (8 per unit) Per unit: 80 |
ARMS Baseplates: 316 Stainless Steel Nylon-Insert Locknut, Super-Corrosion-Resistant, 1/4"-20 Thread Size | McMaster | 90715A125 | Locknuts for ARMS mounting baseplates (struts and Stars) Per unit: 600 |
Coral plate baseplates: 316 Stainless Steel Nylon-Insert Locknut, Super-Corrosion-Resistant, 1/4"-20 Thread Size | McMaster | 90715A125 | Locknuts for attaching coral plate baseplates to struts Per unit: 600 |
Coral plate attach: 316 Stainless Steel Nylon-Insert Locknut, Super-Corrosion-Resistant, 1/4"-20 Thread Size | McMaster | 90715A125 | Locknuts to attach coral plates to baseplates Per unit: 80 |
Mooring bridle: 316 Stainless Steel Nylon-Insert Locknut, Super-Corrosion-Resistant, 1/4"-20 Thread Size | McMaster | 90715A125 | Padeye locknuts for attaching pad eyes to struts. Per unit: 20 |
Main structure: 316 Stainless Steel Nylon-Insert Locknut, Super-Corrosion-Resistant, 10-32 Thread Size | McMaster | 90715A115 | Locknuts for star-strut connections Per unit: 475 |
Main structure: 316 Stainless Steel Pan Head Phillips Screw, 10-32 Thread, 2-1/2" Long | McMaster | 91735A368 | Bolts for star-strut connections Per unit: 475 |
Mooring bridle: 316 Stainless Steel Phillips Flat Head Screws, 1/4"-20 Thread Size, 2-3/4" Long | McMaster | 91500A341 | Padeye bolts for attaching pad eyes to struts. Per unit: 15 |
ARMS Baseplates: 316 Stainless Steel Phillips Flat Head Screws, 1/4"-20 Thread Size, 3" Long | McMaster | 91500A554 | Bolts for attaching ARMS mounting baseplates to Stars Per unit: 475 |
Mooring bridle: 316 Stainless Steel Phillips Flat Head Screws, 1/4"-20 Thread Size, 3" Long | McMaster | 91500A554 | Padeye bolts for attaching pad eyes through struts & Stars. Per unit: 5 |
Mooring bridle: 316 Stainless Steel Screw-Pin Shackle – for Lifting, 1/2" Thick | McMaster | 3583T15 | Shackles to connect lower bridle thimbles to small links on Masterlink. Per unit: 5 |
ARMS attachments: 316 Stainless Steel Split Lock Washer for 1/2" Screw Size, 0.512" ID, 0.869" OD | McMaster | 92147A033 | Lock washers for attaching ARMS to ARMS mounting baseplates (4 per unit) Per unit: 40 |
ARMS attachments: 316 Stainless Steel Washer for 1/2" Screw Size, 0.531" ID, 1.25" OD | McMaster | 90107A033 | Backing washers for attaching ARMS to ARMS mounting baseplates (4 per unit) Per unit: 40 |
ARMS Baseplates: 316 Stainless Steel Washer for 1/4" Screw Size, 0.281" ID, 0.625" OD | McMaster | 90107A029 | Washers for attaching ARMS mounting baseplates to struts Per unit: 40 |
Coral plate baseplates: 316 Stainless Steel Washer for 1/4" Screw Size, 0.281" ID, 0.625" OD | McMaster | 90107A029 | Washers for attaching coral plate baseplates to struts Per unit: 40 |
Coral plate attach: 316 Stainless Steel Washer for 1/4" Screw Size, 0.281" ID, 0.625" OD | McMaster | 90107A029 | Washers to attach coral plates to baseplates Per unit: 160 |
Main structure: 316 Stainless Steel Washer for Number 10 Screw Size, 0.203" ID, 0.438" OD | McMaster | 90107A011 | Washers for star-strut connections Per unit: 475 |
Buoyancy: 316 Stainless Steel Washer, 1" Screw Size, 2" OD | McMaster | 90107A038 | Large washers for central rod (2 per float) Per unit: 22 |
ARMS attachments: 316 Stainless Steel Washer, Oversized, 1/2" Screw, 1.5" OD, 0.052"- 0.072" Thickness | McMaster | 91525A145 | Oversized washers for attaching ARMS to ARMS mounting baseplates (4 per unit) Per unit: 40 |
Coral plates: 3M Marine Adhesive Sealant – Fast Cure 5200 | McMaster | 67015A44 | Adhesive to glue limestone tiles to PVC coral baseplates. Drill out corners with masonry bit. |
Buoyancy: 3M Marine Adhesive Sealant – Fast Cure 5200 | McMaster | 67015A44 | Adhesive for securing fiberglass threaded rods into trawl floats Per unit: 2 |
Mooring bridle: 5/8" Dyneema with Stainless Sailmakers Thimbles at Top and Bottom | West Marine | Custom | 5-leg mooring bridle for attaching Ark to downline. Per unit: 5 |
Downline: Clevis-to-Clevis Swivel – Not for Lifting, 316 Stainless Steel, 6-7/32" Long | McMaster | 37405T29 | Swivel, bottom connects to top of downline, top connects to large link in Masterlink. Per unit: 1 |
Buoyancy: Fiberglass Hex Nut, 1"-8 Thread Size | McMaster | 91395A038 | Fiberglass hex nuts for securing fiberglass threaded rods into trawl floats Per unit: 30 |
Buoyancy: Fiberglass Threaded Rod, 1"-8 Thread Size, 8 Feet Long | McMaster | 91315A238 | Fiberglass threaded rod to attach float to Ark. See Supplemental File 1-Figure SI 16. Per unit: 10 Refers to drawing: Yes |
Anchor system: Galvanized Alloy Steel Shackle with Screw Pin – for Lifting, 1/2" Thick | McMaster | 3663T42 | Middle shackle from chain to pear link. Per unit: 3 |
Anchor system: Galvanized Alloy Steel Shackle with Screw Pin – for Lifting, 3/4" Thick | McMaster | 3663T44 | Upper large shackle to connect pear link to lower downline thimble. Per unit: 1 |
Anchor system: Galvanized Alloy Steel Shackle with Screw Pin – for Lifting, 3/4" Thick | McMaster | 3663T44 | Anchor shackle. Per unit: 3 |
Anchor system: Galvanized Alloy Steel Shackle with Screw Pin – for Lifting, 3/8" Thick | McMaster | 3663T51 | Shackle to connect chain to upper middle shackle. Per unit: 3 |
Anchor system: Galvanized Alloy Steel Shackle with Screw Pin – for Lifting, 3/8" Thick | McMaster | 3663T51 | Lower small shackle to connect chain and anchor shackle. Per unit: 3 |
Install & Tools: HARKEN–57mm Carbo Air® Triple Block | West Marine | 200076 | Top of block and tackle Per unit: 1 |
Install & Tools: HARKEN–57mm Carbo Air® Triple Block with Becket and Cam | West Marine | 1171644 | Base of block and tackle Per unit: 1 |
ARMS Baseplates: Heat-Shrink Tubing, 0.50" ID Before Shrinking | McMaster | 7856K47 | Heatshrink for non-slip. Cut into 1.5" lengths, slide over a SS u-bolt bracket and use heat gun to tighten onto bracket. Per unit: 20 |
Coral plate baseplates: Heat-Shrink Tubing, 0.50" ID Before Shrinking | McMaster | 7856K47 | Heatshrink for non-slip. Cut into 1.5" lengths, slide over a SS u-bolt bracket and use heat gun to tighten onto bracket. Per unit: 40 |
Buoyancy: Heatshrink for covering threaded rods before mounting in floats, 14" sections | McMaster | 7856K66 | Heatshrink for non-slip. Cut into 14" lengths. Slide onto fiberglass rods with 1" exposed on one end and 2-1/4" exposed on the other. Use heat gun to shrink until snug. Per unit: 11 |
Anchor system: High-Strength Grade 40/43 Chain-Not for Lifting, Galvanized Steel, 5/16 Trade Size | McMaster | 3588T23 | Chain to connect anchors and downline. Per unit: 3 |
Install & Tools: LOW-STRETCH ROPE, 7/16" DIAMETER | McMaster | 3789T25 | Rope for block and tackle Per unit: 250 |
ARMS Baseplates: Marine-Grade Moisture-Resistant HDPE, 48" x 48", 1/2" Thick | McMaster | 9785T82 | Sheeting for ARMS mounting baseplates. See Supplemental File 1-Figure SI 13. Per unit: 10 Refers to drawing: Yes |
Coral plate baseplates: Marine-Grade Moisture-Resistant HDPE, 48" x 48", 1/2" Thick | McMaster | 9785T82 | Sheeting for coral plate baseplates. See Supplemental File 1-Figure SI 14. Per unit: 20 Refers to drawing: Yes |
Mooring bridle: Martyr Collar Anode Zinc 3/4" x 2 1/8" x 2 1/8" | West Marine | 5538715 | Sacrificial anodes for Masterlinks on mooring lines Per unit: 2 |
Main structure: Martyr Hull Anode Zinc 6 1/4" x 2 3/4" x 5/8" | West Marine | 484998 | Sacrificial anodes for stainless struts at Ark base Per unit: 3 |
ARMS Baseplates: Mounting Plate for 1/4"-20 Thread Size, 2" ID 304 Stainless Steel U-Bolt | McMaster | 8896T156 | Bracket plate w/heatshrink, for attaching ARMS mounting baseplates to struts Per unit: 6 |
Coral plate baseplates: Mounting Plate for 1/4"-20 Thread Size, 2" ID 304 Stainless Steel U-Bolt | McMaster | 8896T156 | Bracket plate w/heatshrink, for attaching coral plate baseplates to struts Per unit: 40 |
Main structure: N1 Stars, 316 SS, 5mm Thick Connectors for DIY VikingDome F2 Sphere, modified | Viking Dome | ICO2-AISI | N1 Stars modified for central rod. Machine/weld connections to insert top and bottom of unthreaded fiberglass structural rod. See Supplemental File 1-Figure SI 10. Per unit: 2 |
Main structure: N1 Stars, 316 SS, 5mm Thick Connectors for DIY VikingDome F2 Sphere, unmodified | Viking Dome | ICO2-AISI | Unmodified N1 Stars for Ark assembly. See Supplemental File 1-Figure SI 10 Per unit: 10 Refers to drawing: Yes |
Main structure: N2 Stars, 316 SS, 5mm Thick Connectors for DIY VikingDome F2 Sphere, modified | Viking Dome | ICO2-AISI | N2 Stars modified for floats. Drill larger center hole to accommodate 1" threaded fiberglass rod. Per unit: 10 |
Main structure: N2 Stars, 316 SS, 5mm Thick Connectors for DIY VikingDome F2 Sphere, modified | Viking Dome | ICO2-AISI | N2 Stars modified for pad eyes. Drill larger bolt hole (bit – 1/4") on outer hole of one arm for Padeye connector. Per unit: 5 |
Main structure: N2 Stars, 316 SS, 5mm Thick Connectors for DIY VikingDome F2 Sphere, unmodified | Viking Dome | ICO2-AISI | Unmodified N2 Stars for Ark assembly Per unit: 15 |
Anchor system: Pear-Shaped Link – Not for Lifting, Galvanized Steel, 3/4" Thick | McMaster | 3567T34 | Link to connect 3x 1/2" shackles to upper large shackle. Per unit: 1 |
Install & Tools: Phillips Screwdriver, Size No. 2 | McMaster Carr | 5682A28 | Tighten down locknuts on star-strut bolts Per unit: 1 |
Coral plates: PVC Sheet Type 1, Gray, 48" x 48", 1/4" Thick | McMaster | 8747K194 | PVC baseplates for coral plates. See Supplemental File 1-Figure SI 4. Per unit: 20 Refers to drawing: Yes |
Install & Tools: Ratcheting Combination Wrench, 3/4" | McMaster Carr | 5163A21 | Attach ARMS to ARMS mounting baseplates Per unit: 2 |
Install & Tools: Ratcheting Combination Wrench, 3/8" | McMaster Carr | 5163A14 | Tighten down locknuts on star-strut bolts Per unit: 2 |
Install & Tools: Ratcheting Combination Wrench, 7/16" | McMaster Carr | 5163A15 | Attach coral plates to coral plate baseplates Per unit: 2 |
Install & Tools: Round Bend-and-Stay Multipurpose Stainless Steel Wire, 0.012" diameter, 645 feet | McMaster | 9882K35 | Wire for mousing stainless shackles Per unit: 1 |
Main structure: S1 Struts – Structural FRP Fiberglass Square Tube, 2" Wide x 2" High Outside, 1/4" Wall Thickness | McMaster | 8548K34 | Fiberglass S1 Struts. Cut to 20.905" long (531 mm), drill bolt holes (bit – 7/32"), fill w/ divinycell foam & epoxy. See Supplemental File 1-Figure SI 9 Per unit: 55 Refers to drawing: Yes |
Main structure: S1 Struts (SS) – Corrosion-Resistant 316/316L Stainless Steel Rectangular Tube, 0.12" Wall Thickness, 2" x 2" Outside | McMaster | 2937K17 | Stainless S1 Struts. Cut to 20.905" long (531 mm), drill bolt holes (bit – 1/4"). See Supplemental File 1-Figure SI 9. Per unit: 5 Refers to drawing: Yes |
Main structure: S2 Struts – Structural FRP Fiberglass Square Tube, 2" Wide x 2" High Outside, 1/4" Wall Thickness | McMaster | 8548K34 | Fiberglass S2 Struts. Cut to 24.331" long (618 mm), drill bolt holes (bit – 7/32"), fill w/ divinycell foam & epoxy. See Supplemental File 1-Figure SI 9. Per unit: 60 Refers to drawing: Yes |
Anchor system: Skrew SK2500 | Spade Anchor USA | SK2500 | Two-plate sand screw anchors Per unit: 3 |
Coral plates: Stainless Steel Washers for 1/4" Screw Size, 0.281" ID, 0.625" OD | McMaster | 90107A029 | Numbered tags for coral plates. Stamp SS washers with numbered stamps and glue to coral plate for later ID. Per unit: 100 |
Main structure: Structural FRP Fiberglass Rod, 10 Feet Long, 1" Diameter | McMaster | 8543K26 | Central fiberglass rod, cut to Ark diameter Per unit: 1 |
ARMS attachments: Super-Corrosion-Resistant 316 Stainless Steel Hex Head Screw, 1/2"-13 Thread Size, 1-3/4" Long | McMaster | 93190A718 | Bolts for attaching ARMS to ARMS mounting baseplates (4 per unit) Per unit: 40 |
Coral plate attach: Super-Corrosion-Resistant 316 Stainless Steel Hex Head Screw, 1/4"-20 Thread Size, 2" Long, Fully Threaded | McMaster | 93190A550 | Bolts to attach coral plates to baseplates Per unit: 80 |
ARMS Baseplates: Super-Corrosion-Resistant 316 Stainless Steel Hex Head Screw, 1/4"-20 Thread Size, 3-1/2" Long | McMaster | 92186A556 | Bolts for attaching ARMS mounting baseplates to struts Per unit: 40 |
Coral plate baseplates: Super-Corrosion-Resistant 316 Stainless Steel Hex Head Screw, 1/4"-20 Thread Size, 3" Long, Partially Threaded | McMaster | 92186A554 | Bolts for attaching coral plate baseplates to struts Per unit: 160 |
Buoyancy: TFLOAT 14" CENTERHOLE OR 437FM, modified | Seattle Marine | YUN12B-8 | 14" trawl floats for mounting to Stars. Slide fiberglass rod with heat shrink through trawl float. Add stainless washer and fiberglass hex nut on both sides. Seal washers with 3M 5200. Tighten nuts down. See Supplemental File 1-Figure SI 16. Per unit: 11 Refers to drawing: Yes |
Buoyancy: TFLOAT 14" CENTERHOLE OR 437FM, unmodified | Seattle Marine | YUN12B-8 | 14" trawl float Per unit: 2 |
ARMS Baseplates: Thick-Wall Dark Gray PVC Pipe for Water, Unthreaded, 1/4 Pipe Size, 5 Feet Long | McMaster | 48855K41 | Star standoffs for attaching ARMS mounting baseplates to Stars. Cut to 1.75" long sections. Per unit: 40 |
Coral plates: Unfilled, Natural Travertine Flooring Tile, 16" x 16" | Home Depot | 304540080 | Limestone tiles for coral plates. Cut to 9" x 9" tiles using wet tile saw. Per unit: 20 |
Buoyancy: Vibration-Damping Routing Clamp, Weld mount, Polypropylene with Stainless Steel Plates, 1" ID | McMaster | 3015T47 | Attachment for central rod and float Per unit: 1 |
Buoyancy: Water- and Steam-Resistant Fiberglass Washer for 1" Screw Size, 1.015" ID, 1.755" OD | McMaster | 93493A110 | Fiberglass washers for securing fiberglass threaded rods into trawl floats Per unit: 20 |
Install & Tools: Zinc-Galvanized Steel Wire, 0.014" diameter, 475 feet long | McMaster | 8872K19 | Wire for mousing galvanized shackles Per unit: 1 |
Two Platform Ark | |||
Downline: 1" Nylon, 15' length thimble-to-thimble with SS Sailmaker Thimble spliced at top, galvanized thimble spliced at bottom | West Marine | Custom | Runs from bottom of swivel shackle (SS) to top of anchor system (galvanized) Per unit: 1x |
Downline: 1/2" Spectra Rope with SS316 Sailmakers Thimbles Spliced at Top and Bottom | West Marine | Custom | Runs from bottom of Ark to top of swivel shackle. Per unit: 2x |
Buoyancy: 1/2" Spectra Rope with SS316 Sailmakers Thimbles Spliced at Top and Bottom | West Marine | Custom | Connects mooring buoy to top eye on Ark Per unit: 2x |
Main structure: 3/8 x 36 Inch SS Thimble Eye Swages and 5/8 Jaw-Jaw Turnbuckle Cable Assembly | Pacific Rigging & Loft | Custom | Custom rigging system with turnbuckle, 3/8" SS wire rope swaged into PVC end caps Per unit: 1x |
Main structure: 304 SS U-Bolt with Mounting Plate, 1/4"-20, 2" ID | McMaster Carr | 8896T123 | For joining fiberglass platforms using I-beams Per unit: 10x |
Main structure: 316 SS Hex Nut, 1/4"-20 | McMaster Carr | 94804A029 | For locking struts in hubs Per unit: 120x |
Main structure: 316 SS Nylon-Insert Locknut, 1/4"-20 | McMaster Carr | 90715A125 | For locking struts in hubs Per unit: 240x |
Main structure: 316 SS Pan Head Phillips Screw, 1/4"-20 Thread, 2.5" Long | McMaster Carr | 91735A384 | For locking struts in hubs Per unit: 120x |
Downline: 316 SS Safety-Pin Shackle, 1/2" Thick | McMaster Carr | 3860T25 | Connect Ark bottom eye to 1/2" Spectra rope. Per unit: 1x |
Buoyancy: 316 SS Safety-Pin Shackle, 1/2" Thick | McMaster Carr | 3860T25 | Connects bottom of 1/2" rope to top Ark eye Per unit: 2x |
Buoyancy: 316 SS Safety-Pin Shackle, 7/16" Thick | McMaster Carr | 3860T24 | Connects mooring buoy to 1/2" rope Per unit: 2x |
Install & Tools: Arbor with 7/16" Hex for 1-1/2" Diameter Hole Saw | McMaster Carr | 4066A63 | Drill holes in 6" PVC (Hubs) Per unit: 1x |
Main structure: Clamping U-bolt, 304 SS, 1/4"-20 Thread Size, 9/16" ID | McMaster Carr | 3042T149 | For clamping SS wire rope at Ark vertices Per unit: 15x |
Downline: Clevis-to-Clevis Swivel, 316 SS, 5-7/16" Long | McMaster Carr | 37405T28 | Swivel shackle between 1/2" spectra rope and 1" nylon downline Per unit: 1x |
Main structure: Corrosion-Resistant Wire Rope, 316 SS, 1/8" Thick | McMaster Carr | 8908T44 | String through assembled Ark and clamp at vertices Per unit: 250ft |
Main structure: Fiberglass Molded Grating, Square Grid, 1" Grid Height, 1-1/2" x 1-1/2" Square Grid, Grit Surface, 70% Open Area | McNichols | MS-S-100 | Cut to half pentagon shape, mirror images. See Figure S23. Per unit: 2x Refers to drawing: Yes |
Anchor system: Galvanized Alloy Steel Screw-Pin Shackle, 1/2" Thick | McMaster Carr | 3663T42 | Connects base of 1" nylon downline to anchor chain Per unit: 1x |
Anchor system: Galvanized Alloy Steel Screw-Pin Shackle, 3/8" Thick | McMaster Carr | 3663T51 | Connects anchor chain together Per unit: 1x |
Anchor system: Grade 30 Chain, Galvanized Steel, 1/4 Trade Size | McMaster Carr | 3592T45 | Anchor chain |
Install & Tools: HARKEN–57 mm Carbo Air Triple Block | West Marine | 200076 | Top of block and tackle Per unit: 1x |
Install & Tools: HARKEN–57 mm Carbo Air Triple Block with Becket and Cam | West Marine | 1171644 | Base of block and tackle Per unit: 1x |
Install & Tools: Hole Saw, 1-15/16" Cutting Depth, 1-1/2" Diameter | McMaster Carr | 4066A27 | Drill holes in 6" PVC (Hubs) Per unit: 1x |
Install & Tools: Low Pressure Inflator Nozzle | Amazon (Made by Trident) | B00KAI940E | Inflate mooring buoys underwater Per unit: 1x |
Install & Tools: LOW-STRETCH ROPE, 7/16" DIAMETER | McMaster | 3789T25 | Rope for block and tackle Per unit: 100ft |
Main structure: Nylon Cable Ties, UV Resistant Heavy Duty, 19" long, 250 lb strength | CableTiesAndMore | CT19BK | Use to secure platforms to Ark framework Per unit: 30x |
Install & Tools: Phillips Screwdriver, Size No. 3 | McMaster Carr | 5682A29 | For locking struts in hubs Per unit: 1x |
Buoyancy: Polyform Buoy, A-5 Series All-Purpose Buoy, 27" | West Marine (Made by PolyformUS) | 11630142 | Mooring buoy for buoyancy. Per unit: 2x |
Main structure: PVC Pipe, Schedule 80, 1" diameter | McMaster Carr | 48855K13 | Struts. Cut to 1.2 m (4 ft) lengths, drill to accommodate bolts Per unit: 30x |
Main structure: PVC Pipe, Schedule 80, 6" diameter | McMaster Carr | 48855K42 | Hubs. Cut into 4" lengths, drill 5 holes symmetrically around midline using 1-1/2" hole saw. See Supplemental File 1-Figure S22. Per unit: 12x Refers to drawing: Yes |
Main structure: PVC Thick Wall Pipe Fitting, End Cap, Schedule 80, 6 " diameter, Female | PRMFiltration (Made by ERA) | PVC80CAP600X | End caps for top and bottom of Ark. Cut off bottom 2 inches. Per unit: 2x |
Install & Tools: Ratcheting Combination Wrench, 7/16" | McMaster Carr | 5163A15 | For locking struts in hubs Per unit: 1x |
Install & Tools: Ratcheting PVC Cutter, 1-1/4" | McMaster Carr | 8336A11 | Cut 1" PVC into struts Per unit: 1x |
Main structure: Ring, 18-8 SS, for 5/32 Chain Trade Size, 3/4" Inside Length | McMaster Carr | 3769T71 | Substitute for 1/2" SS wire rope clamps. Per unit: 12x |
Install & Tools: Round Bend-and-Stay Multipurpose Stainless Steel Wire, 0.012" diameter, 645 feet | McMaster | 9882K35 | Wire for mousing stainless shackles Per unit: 1 |
Main structure: Structural FRP Fiberglass I-Beam, 1/4" Wall Thickness, 1-1/2" Wide x 3" High, 5 ft long | McMaster Carr | 9468T41 | Cut to 5 1-ft long sections. Per unit: 1x |
Install & Tools: Underwater Lift Bag, 220 lbs Lift Capacity | Subsalve Commercial | C-200 | Transport Ark to deployment site Per unit: 1x |
Install & Tools: Zinc-Galvanized Steel Wire, 0.014" diameter, 475 feet long | McMaster | 8872K19 | Wire for mousing galvanized shackles Per unit: 1x |
Strain Gauge | |||
316 Stainless Steel Eyebolt, for Lifting, M16 x 2 Thread Size, 27 mm Thread Length | McMaster Carr | 3130T14 | For strain gauge eyebolts Per unit: 2x |
Bridge101A Data Logger, 30 mV | MadgeTech | Bridge101A-30 | Collect voltage data from load cell. Per unit: 1x |
Chemical-Resistant PVC Rod, 2" Diameter | McMaster Carr | 8745K26 | For datalogger housing endcap. See Supplemental File 1-Figure S32. Per unit: 1x Refers to drawing: Yes |
Clamping U-Bolt, 304 SS, 5/16"-18 Thread Size, 1-3/8" ID | McMaster Carr | 3042T154 | For attachment of datalogger housing to strain gauge. Per unit: 1x |
Dow Corning Molykote 44 Medium Grease Lubricant | Amazon (Made by Dow Corning) | B001VY1EL8 | For mating male and female underwater connectors. Per unit: 1x |
STA-8 Stainless Steel S Type Tension and Compression Load Cell | LCM Systems | STA-8-1T-SUB | Load cell instrument for assessment of in-water weight. Per unit: 1x |
Standard-Wall Clear Blue Rigid PVC Pipe for Water, Unthreaded, 1-1/2 Pipe Size, 2 ft | McMaster Carr | 49035K47 | For datalogger housing. See Supplemental File 1-Figure S31. Per unit: 1x Refers to drawing: Yes |
Standard-Wall PVC Pipe Fitting for Water, Cap, White, 1-1/2 Pipe Size Socket Female | McMaster Carr | 4880K55 | For datalogger housing. Per unit: 2x |
Structural FRP Fiberglass Sheet, 12" Wide x 12" Long, 3/16" Thick | McMaster Carr | 8537K24 | For attachment of datalogger housing to strain gauge. Per unit: 1x |
SubConn Micro Circular Connector, Female, 4-port | McCartney (Made by SubConn) | MCBH4F | Install into machined housing endcap. Per unit: 1x |
SubConn Micro Circular Connector, Male, 4-contact | McCartney (Made by SubConn) | MCIL4M | Splice to load cell wiring and waterproof connection. Per unit: 1x |
Threadlocker, Loctite 262, 0.34 FL. oz Bottle | McMaster Carr | 91458A170 | For strain gauge eyebolts Per unit: 1x |
Vibration-Damping Routing Clamp, Weld-Mount, Polypropylene with Zinc-Plated Steel Top Plate, 1-7/8" ID | McMaster Carr | 3015T39 | For attachment of datalogger housing to strain gauge. Per unit: 1x |