Physiological response to temperature, light, and nitrates in the giant kelp Macrocystis pyrifera, from Tasmania, Australia
Physiological response to temperature, light, and nitrates in the giant kelp Macrocystis pyrifera, from Tasmania, Australia
复制标题
澳大利亚塔斯马尼亚巨藻巨藻对温度、光和硝酸盐的生理反应
DOI：
10.3354/meps12900
复制
发表时间：
2019
影响因子：
2.5
通讯作者：
Jeffrey T. Wright
中科院分区：
文献类型：
--
作者：
Christopher J T Mabin;C. Johnson;Jeffrey T. Wright
气候变化的特点是多种非生物强迫同时作用于生物系统。在海洋系统中，温度似乎驱动了受气候变化影响的生物群落的大部分观察到的变化，但这可能反映了大多数研究只关注温度，而不考虑受气候变化影响的其他环境变量。巨型巨藻Macrocystis pyrifera曾经在塔斯马尼亚东部非常丰富，形成了广泛的生态和经济重要性的栖息地，但最近发生了广泛的人口下降。温暖的贫营养东澳大利亚洋流（EAC）向南入侵该地区的频率和强度都有所增加，该地区的变暖幅度约为全球平均水平的4倍，预计变暖趋势将持续下去。研究了温度、光照和硝态氮供应量单独和联合作用对红腹锦鸡儿幼鱼生理的影响。pyrifera孢子体在实验室实验。测定的相对生长速率，光系统II特性，色素，元素化学和核酸特性超过28天表明，所有实验因素影响孢子生理。温度和光驱动的性能特性相关的观察到的变化，海带组织的快速恶化的结果是温度胁迫（高温），光抑制（高光），和低光，伴随着受损的光合效率和RNA浓度增加，推测与生产的光保护蛋白。令人惊讶的是，在低硝酸盐处理中观察到较高的相对生长率。这些结果表明，温度对M。pyrifera种群将由光照和营养条件的局部变化介导。
Climate change is characterised by multiple abiotic forcings acting simultaneously on biotic systems. In marine systems, temperature appears to drive much of the observed change in biotic communities subject to climate change, but this may reflect the focus of most studies only on temperature without consideration of other environmental variables affected by climate change. The giant kelp Macrocystis pyrifera was once abundant in eastern Tasmania, forming extensive habitats of ecological and economic importance, but recent extensive population decline has occurred. Southerly incursion of warm oligotrophic East Australian Current (EAC) water has increased in frequency and intensity into this region, which has warmed ~4 times the global average, and the warming trend is predicted to continue. This study investigated the single and combined effects of temperature, light, and nitrate availability on the physiology of juvenile M. pyrifera sporophytes in a laboratory experiment. Determination of relative growth rate, photosystem II characteristics, pigments, elemental chemistry, and nucleic acid characteristics over 28 d showed that all experimental factors affected sporeling physiology. Temperature and light drove much of the observed variation related to performance characteristics, and rapid deterioration of kelp tissue was a consequence of temperature stress (high temperature), photoinhibition (high light), and low light, accompanied by impaired photosynthetic efficiency and increased RNA concentration, presumably associated with production of photoprotective proteins. Surprisingly, higher relative growth rates were observed in low-nitrate treatments. These findings suggest that negative effects of temperature on M. pyrifera populations will be mediated by local variation in light and nutrient conditions.