Bloom dynamics of Dinophysis acuta in an upwelling system: In situ growth versus transport
Bloom dynamics of Dinophysis acuta in an upwelling system: In situ growth versus transport
复制标题
DOI：
10.1016/j.hal.2009.12.002
复制
发表时间：
2010-03-01
期刊：
影响因子：
6.6
通讯作者：
Ruiz-Villarreal, Manuel
中科院分区：
文献类型：
--
作者：
Escalera, Laura;Reguera, Beatriz;Ruiz-Villarreal, Manuel
牙藻的开花。与亲脂性贝类有关的毒素暴发在伊比利亚西北部水域从春季到秋季很常见。尖锐地藻的水华具有很强的季节性(夏末-初秋)；在上升流季节，它们在葡萄牙北部水域较早开始，并在上升流季节结束时，在加利西亚里亚海达到最大值。关于RIA中细胞密度的突然增加是由于先前在邻近陆架水域建立的种群的跨陆架运输所致，还是由于沿海运输将葡萄牙附近海域的种群带到了北部，存在争议。2005年，9月初在阿维罗附近的葡萄牙海域观察到了创纪录的尖锐螺旋体浓度(14×10(4)室L-1)，而加利西亚海岸的浓度非常中等(10(2)-10(3)室L-1)。在秋季由上升风向下流风转变的过程中，尖吻金鱼在葡萄牙近海突然减弱，而在加利西亚海发现了年最大值(高达22x10(3)格子L-1)。采用了一种新的方法，该方法结合了物理观测(SST，当前测量)；加利西亚和葡萄牙监测方案的每周观测；Ria de Vigo的尖吻金线虫的周分率估计，以及Ria de Vigo的每月横断面和额外的特别抽样。在8月和9月初，Ria de Vigo的分裂率很高，但浓度很低，而葡萄牙较高的SST值(代表热层结)似乎促进了尖锐水母高密度的建立。在10月的最后一周和11月的第一周，种群数量下降，而在加利西亚，种群达到了最大密度，而分裂比率估计几乎为零。这里提供的结果证实，加利西亚海区的数量增加不是由于内在的生长，而是由于物理驱动的积累；在积累期计算的简单的细胞浓度平衡表明，在没有细胞分裂的情况下，在下流期间观察到的高净增长，一定是由于通过沿海运输输入的细胞。(C)2009爱思唯尔B.V.保留所有权利。
Blooms of Dinophysis spp. associated with lipophilic shellfish toxin outbreaks are common in Northwestern Iberia waters from spring to autumn. Blooms of Dinophysis acuta are very seasonal (late summer-early autumn); they start earlier in Northern Portuguese waters during the upwelling season, and reach their maximum values in the Galician Rias during downwelling events at the end of the upwelling season. There is controversy about whether sudden increases in cell concentrations in the rias result from cross-shelf transport of populations previously established in adjacent shelf waters, or are due to longshore transport that brings populations located off Portugal to the North. In 2005, record concentrations of D. acuta were observed in Portuguese waters (14 x 10(4) cell L-1) off Aveiro in early September, while concentrations off the Galician coast were very moderate (10(2)-10(3) cell L-1). During the autumn transition from upwelling- to downwelling-favourable winds, D. acuta declined abruptly off Portugal while the annual maximum (up to 22 x 10(3) cell L-1) was found in the Galician Rias. A new approach was used that combined physical observations (SST, current measurements); weekly observations from monitoring programmes in Galicia and Portugal; weekly division rate (Amin) estimates of D. acuta in Ria de Vigo, together with monthly transects and additional ad hoc sampling in the Ria. During August and early September, division rates were high in Ria de Vigo but concentrations were low, whereas higher SST values in Portugal (a proxy for thermal stratification) seemed to promote the build up of high densities of D. acuta. During the last week of October and the first week of November, populations declined, whereas in Galicia, maximum concentrations were reached while division rate estimates were almost zero. Results presented here confirm that increased numbers in the Galician Rias are not due to intrinsic growth but to physically driven accumulation; a simple cell concentration budget calculated during the accumulation period suggests that the high net growth observed during downwelling, in the absence of cellular division, must be due to cells imported by longshore transport. (C) 2009 Elsevier B.V. All rights reserved.