Effects of low salinity on the physiological ecology of planulae and polyps of scyphozoans in the East Asian Marginal Seas: potential impacts of monsoon rainfall on medusa population size
Effects of low salinity on the physiological ecology of planulae and polyps of scyphozoans in the East Asian Marginal Seas: potential impacts of monsoon rainfall on medusa population size
复制标题
DOI：
10.1007/s10750-018-3558-3
复制
发表时间：
2018-03
期刊：
影响因子：
2.6
通讯作者：
Mariko Takao;S. Uye
中科院分区：
文献类型：
--
作者：
Mariko Takao;S. Uye
据推测，盐度会影响东亚边缘海中水母类的丰度，因为它们的产卵主要与夏季季风季节相吻合，而极端干旱会使浮游生物的盐度降低，可能会危及水螅的招募。本文研究了不同盐度（5、10、15、20、25和32）对三种水华形成的钵水母（Chrysaora pacifica、Nemopilema nomurai和Rhopilema esculentum）的体型、游泳速度、浮浪的存活和沉降以及随后的变态息肉发育的影响。渗透胁迫对它们的生理和行为都有影响，但种间差异较大。在5，所有物种的浮浪死亡。在10摄氏度。pacific不能定居，但作为浮游生物生存，而N.诺穆兰河石菖蒲可定居并发育为四腱息肉，但前者表现为发育延迟和腱异常。允许息肉正常募集的最低盐度分别为10、15和20。esculentum，N. nomurai和C.太平洋，分别。季风降雨的年际变化可以改变水螅栖息地的水文条件，影响次年的水母种群规模。对低盐胁迫的适应性较强。esculentumandN. nomurailarterium可能使他们能够建立尚未确定的水螅种群在咸水环境中。
Salinity is hypothesized to influence the abundance of scyphozoan medusae in the East Asian Marginal Seas, as their spawning largely coincides with the summer monsoon season, and extreme rainfalls subject planulae to reduced salinity, presumably jeopardizing the recruitment of polyps. We examined the effects of different salinities (5, 10, 15, 20, 25, and 32) on body size, swimming speed, survivorship and settlement of planulae, and subsequent development of metamorphosed polyps of three bloom-forming scyphozoans:Chrysaora pacifica,Nemopilema nomurai, andRhopilema esculentum. Their physiology and behaviors were affected by osmotic stress, but differed by species. At 5, planulae of all species died. At 10,C. pacificacould not settle but survived as plankton, whereasN. nomuraiandR. esculentumcould settle and develop into four-tentacle polyps, yet the former showing delayed development and tentacle abnormalities. The lowest salinities permitting normal recruitment of polyps were 10, 15, and 20 forR. esculentum,N. nomurai, andC. pacifica, respectively. Inter-annual variations in monsoon rainfall can alter hydrographic conditions in the polyp habitats, affecting medusa population sizes in the following year. The robustness to low salinity ofR. esculentumandN. nomurailarvae may enable them to establish yet-to-be-identified polyp populations in brackish-water environments.