Blomberg Brittany N, Lebreton Benoit, Palmer Terence A, Guillou Gaël, Beseres Pollack Jennifer, Montagna Paul A
Harte Research Institute for Gulf of Mexico Studies, Texas A&M University - Corpus Christi, 6300 Ocean Drive, Unit 5869, Corpus Christi, TX 78412-5869, USA.
Institut du Littoral et de l'Environnement, Université de La Rochelle, 2 rue Olympe de Gouges, 17000 La Rochelle, France.
Mar Environ Res. 2017 Jun;127:32-40. doi: 10.1016/j.marenvres.2017.03.003. Epub 2017 Mar 11.
As ecosystem engineers, oysters create and maintain structured habitat and can influence trophodynamics and benthic-pelagic coupling in the surrounding landscape. The physical reef structure and associated biotic parameters can affect the availability of food resources for oysters. Oysters and potential composite food sources - suspended particulate organic matter (SPOM) and surface sediment organic matter (SSOM) - were assessed using a dual stable isotope (δC, δN) approach at three reef types (natural, restored, and unconsolidated) seasonally for two years to determine if changes in physical and/or biotic parameters affected the relative availability and/or use of food resources by oysters. SPOM was more depleted in C (-24.2 ± 0.6‰, mean ± SD) than SSOM (-21.2 ± 0.8‰). SPOM composition is likely dominated by autochthonous phytoplankton production, while SSOM includes trapped phytoplankton and benthic microalgae. SSOM was used by oysters in increasing proportions relative to SPOM over time at all reef types. This temporal trend is likely due to increased oyster biomass over time, promoting enhanced microphytobenthos growth through feedback effects related to oyster biodeposits. Structural differences between reef types observed in this study had no effect on food resource availability and use by oysters, indicating strong bentho-pelagic coupling likely due to shallow depths as well as strong and consistent winds. This study provides insights for restoration of oyster reefs as it highlights that food resources used by oysters remain similar among reef types despite changes in abiotic and biotic parameters among habitats and over time.
作为生态系统工程师，牡蛎创造并维持结构化栖息地，还能影响周围景观中的营养动力学和底栖-水层耦合。物理礁体结构和相关生物参数会影响牡蛎的食物资源可利用性。使用双稳定同位素（δC、δN）方法，在两年的时间里，季节性地对三种礁体类型（天然礁体、修复礁体和未固结礁体）的牡蛎以及潜在的复合食物来源——悬浮颗粒有机物（SPOM）和表层沉积物有机物（SSOM）进行评估，以确定物理和/或生物参数的变化是否会影响牡蛎对食物资源的相对可利用性和/或利用情况。SPOM的碳含量（-24.2 ± 0.6‰，平均值±标准差）比SSOM（-21.2 ± 0.8‰）贫化程度更高。SPOM的组成可能主要是本地浮游植物的产物，而SSOM包括捕获的浮游植物和底栖微藻。在所有礁体类型中，随着时间的推移，牡蛎对SSOM的利用比例相对于SPOM不断增加。这种时间趋势可能是由于牡蛎生物量随时间增加，通过与牡蛎生物沉积物相关的反馈效应促进了微型底栖植物的生长。本研究中观察到的礁体类型之间的结构差异对牡蛎的食物资源可利用性和利用情况没有影响，这表明可能由于深度较浅以及强而持续的风力，导致了强烈的底栖-水层耦合。这项研究为牡蛎礁的修复提供了见解，因为它强调尽管栖息地之间的非生物和生物参数随时间发生了变化，但不同礁体类型中牡蛎利用的食物资源仍然相似。
