PDF(Pubmed)
Abstract：
High abundances of gelatinous zooplankton (GZ) can significantly impact marine ecosystem by acting as both sink and source of organic matter (OM) and nutrients. The decay of GZ bloom can introduce significant amount of OM to the ocean interior, with its variability influenced by GZ life traits and environmental factors, impacting microbial communities vital to marine biogeochemical cycles. The invasive ctenophores Mnemiopsis leidyi has formed massive blooms in the northern Adriatic Sea since 2016. However, the variability in the chemical composition and egg production of blooming populations, as well as the role of environmental factors in governing this variability, remains largely unknown. Our analysis of biometry, chemical composition, and fecundity of M. leidyi sampled in the Gulf of Trieste in 2021 revealed stable carbon and nitrogen content throughout bloom development, with no significant correlation with seawater temperature, salinity, oxygen, and chlorophyll a concentration. Although the studied population exhibited homogeneity in terms of biometry and chemical composition, the number of produced eggs varied substantially, showing no clear correlation with environmental variables and being somewhat lower than previously reported for the study area and other Mediterranean areas. We observed a positive correlation between the wet weight of individuals and the percentage of hatched eggs, as well as a significant positive correlation between the percentage of hatched eggs and ambient seawater temperature. Additionally, we noted that the speed of hatching decreased with decreasing seawater temperature in autumn, corresponding to the end of M. leidyi bloom.
摘要：
大量的凝胶状浮游动物（GZ）可以通过充当有机质（OM）和养分的汇和来源来显着影响海洋生态系统。GZ水华的衰变可以将大量的OM引入海洋内部，其变异性受GZ生活特征和环境因素的影响，影响对海洋生物地球化学循环至关重要的微生物群落。自2016年以来，入侵性的食子病毒Mnemimopsisleidyi在亚得里亚海北部形成了大量的水华。然而,开花种群的化学成分和产蛋量的变化，以及环境因素在控制这种可变性中的作用，仍然很大程度上未知。我们对生物统计学的分析，化学成分,2021年在的里雅斯特湾采样的M.leidyi的繁殖力显示，在整个水华发育过程中，碳和氮含量稳定，与海水温度没有显著相关性，盐度,氧气,和叶绿素a浓度。尽管所研究的人群在生物特征和化学成分方面表现出同质性，产卵的数量变化很大，与环境变量没有明显的相关性，并且比以前报告的研究区域和其他地中海地区的要低一些。我们观察到个体的湿重与孵化卵的百分比之间存在正相关关系，以及孵化卵的百分比与周围海水温度之间的显着正相关。此外,我们注意到秋季孵化速度随着海水温度的降低而降低，对应于M.leidyibloom的结尾。
