Cooperative Institute for Marine Resources Studies, Hatfield Marine Science Center, 2030 SE Marine Science Drive Newport, OR 97365, Oregon State University, USA; Institute Jožef Stefan, 1000 Ljubljana, Slovenia.
Washington Department of Ecology, Olympia, 300 Desmond Dr SE, WA 98503,(Emeritus), USA.
Sci Total Environ. 2024 Oct 1;945:174065. doi: 10.1016/j.scitotenv.2024.174065. Epub 2024 Jun 17.
Kelps are recognized for providing many ecosystem services in coastal areas and considered in ocean acidification (OA) mitigation. However, assessing OA modification requires an understanding of the multiple parameters involved in carbonate chemistry, especially in highly dynamic systems. We studied the effects of sugar kelp (Saccharina latissima) on an experimental farm at the north end of Hood Canal, Washington-a low retentive coastal system. In this field mesocosm study, two oyster species (Magallana gigas, Ostrea lurida) were exposed at locations in the mid, edge, and outside the kelp array. The Hood Head Sugar Kelp Farm Model outputs were used to identify dominating factors in spatial and temporal kelp dynamics, while wavelet spectrum analyses helped in understanding predictability patterns. This was linked to the measured biological responses (dissolution, growth, isotopes) of the exposed organisms. Positioned in an area of high (sub)-diel tidal fluxes with low retention potential, there were no measurable alterations of the seawater pH at the study site, demonstrating that the kelp array could not induce a direct mitigating effect against OA. However, beneficial responses in calcifiers were still observed, which are linked to two causes: increased pH predictability and improved provisioning through kelp-derived particulate organic resource utilization and as such, kelp improved habitat suitability and indirectly created refugia against OA. This study can serve as an analogue for many coastal bay habitats where prevailing physical forcing drives chemical changes. Future macrophyte studies that investigate OA mitigating effects should focus also on the importance of predictability patterns, which can additionally improve the conditions for marine calcifiers and ecosystem services vulnerable to or compromised by OA, including aquaculture sustainability.
海带被认为在沿海地区提供了许多生态系统服务，并被认为可以缓解海洋酸化（OA）。然而，评估 OA 变化需要了解碳酸盐化学涉及的多个参数，尤其是在高度动态的系统中。我们研究了糖海带（Saccharina latissima）在华盛顿胡德运河北端的一个实验农场的影响，这是一个低保留率的沿海系统。在这个田间中观实验研究中，两种牡蛎物种（Magallana gigas，Ostrea lurida）被暴露在海带阵列的中间、边缘和外部位置。使用 Hood Head Sugar Kelp Farm Model 输出来确定海带动态的空间和时间上的主导因素，而小波谱分析有助于理解可预测性模式。这与暴露生物的测量生物反应（溶解、生长、同位素）相关联。该位置处于潮汐通量高（亚）日变化且保留潜力低的区域，研究地点的海水 pH 值没有可测量的变化，这表明海带阵列不能对 OA 产生直接的缓解作用。然而，仍然观察到钙化生物的有益反应，这与两个原因有关：pH 值可预测性的增加，以及通过利用海带衍生的颗粒有机资源来改善供应，从而改善栖息地适宜性并间接为 OA 创造避难所。本研究可作为许多沿海海湾栖息地的模拟，这些栖息地的主要物理驱动力会导致化学变化。未来研究 OA 缓解作用的大型藻类研究应重点关注可预测性模式的重要性，这可以进一步改善海洋钙化生物和易受 OA 影响或受 OA 影响的生态系统服务的条件，包括水产养殖的可持续性。
