Lethal and sublethal effects of sediment burial on the eastern oyster Crassostrea virginica
Lethal and sublethal effects of sediment burial on the eastern oyster Crassostrea virginica
复制标题
DOI：
10.3354/meps11244
复制
发表时间：
2015-05-07
影响因子：
2.5
通讯作者：
Lipcius, Romuald N.
中科院分区：
文献类型：
--
作者：
Colden, Allison M.;Lipcius, Romuald N.
东方牡蛎Crassostrea virgiica是主要的生态工程师，在河口系统中建造复杂的珊瑚礁。珊瑚礁的持久性依赖于珊瑚礁的生长，而珊瑚礁的生长必须超过珊瑚礁的退化和沉积物的沉积。埋葬对牡蛎存活的定量影响以及沉积物沉积的亚致死效应尚不确定。在这项中观研究中，我们量化了部分和完全埋藏(牡蛎壳高度的0、50、70、90和110%)对牡蛎(壳高25-75 mm)的存活、生物沉积、条件指数和生长的影响。只有当90%或更多的牡蛎被掩埋时，存活率才会显着下降；导致50%死亡的临界埋深是108%。这一发现将使牡蛎的死亡率成为沉积物负荷和牡蛎大小的函数。生物沉降量和状态指数与埋藏深度呈负相关，贝壳生长随埋深增加而增加。生物沉积量和状态指数的下降可能与埋葬和将能源重新分配给贝壳生长造成的摄食中断有关。贝壳生长的增加类似于动物区系物种的垂直迁移-埋藏的牡蛎增加了垂直的贝壳生长，以突破沉积物表面取食和呼吸，以牺牲组织生长为代价。虽然牡蛎在存活方面可以容忍部分埋葬，但埋葬会对新陈代谢过程产生不利影响，从而影响人口统计比率和珊瑚礁的持久性。今后的管理工作应考虑部分埋葬的影响，这往往比导致大规模死亡的灾难性埋葬事件发生得更频繁。
Eastern oysters Crassostrea virginica are dominant ecosystem engineers that construct complex reefs in estuarine systems. Reef persistence relies on reef growth, which must outpace reef degradation and sediment deposition. The quantitative impact of burial on oyster survival and sublethal effects of sediment deposition are undefined. In this mesocosm study, we quantified effects of partial and complete burial (0, 50, 70, 90, and 110% of oyster shell height) on survival, biodeposition, condition index and growth of oysters (shell height = 25-75 mm). Survival only declined significantly when 90% or more of an oyster was buried; the critical burial depth inducing 50% mortality was 108%. This finding will allow scaling of mortality rates of oysters as a function of sediment load and oyster size. Biodeposition and condition index were negatively related to burial depth, whereas shell growth increased with burial depth. Decreases in biodeposition and condition index were likely related to disruption of feeding by burial and reallocation of energy resources to shell growth. The increase in shell growth was analogous to vertical migration of infaunal species-buried oysters increased vertical shell growth to breach the sediment surface to feed and respire, at the expense of tissue growth. While oysters are tolerant of partial burial in terms of survival, burial adversely affects metabolic processes that influence demographic rates and reef persistence. Future management efforts should consider the effects of partial burial, which often occur more frequently than catastrophic burial events causing mass mortality.