The decline and recovery of a persistent Texas brown tide algal bloom in the Laguna Madre (Texas, USA)
The decline and recovery of a persistent Texas brown tide algal bloom in the Laguna Madre (Texas, USA)
复制标题
DOI：
10.2307/1353236
复制
发表时间：
2001-06-01
期刊：
影响因子：
--
通讯作者：
Bersano, JGF
中科院分区：
文献类型：
--
作者：
Buskey, EJ;Liu, HB;Bersano, JGF
拉古纳马德雷已经经历了八年多的Aureoumbra lagunensis持续开花。这种水华的持续性可能部分是由于拉古纳马德雷（40-60 psu）的高盐条件有利于A。拉贡内斯1997年秋季的正常降雨量使巴芬湾的盐度从1997年7月的> 40至< 20 psu. A. lagunensis cell densities dropped from >10（6）个细胞ml（-1）降至1997年7月的c. 200个细胞ml（-1）。在这段时间的低棕色潮汐密度，浮游植物生物量普遍保持高水平，拉古纳马德雷经历了连续的硅藻（Rattellasolenia spp.）和蓝藻。1998年，高盐环境再次出现，到了夏季，褐潮密度增加到> 0.5 x 10（6）个细胞/ml。褐潮的异常持久性和不寻常的密集水华序列可能部分与浮游动物数量的减少有关。微型浮游动物种群下降后，在1997年的失败高于正常的降雨，人口没有恢复，直到1998年秋季。桡足类种群也急剧下降，并保持在低拉古纳马德雷，但恢复到1998年夏季在巴芬湾。稀释实验表明，微型浮游动物的放牧和浮游植物的生长通常是平衡的，在我们的巡航测量。A. lagunensis水华表明，这可能是一个更有弹性的组成部分，拉古纳马德雷植物群比以前怀疑。
The Laguna Madre has experienced a persistent bloom of Aureoumbra lagunensis for over eight years. The persistence of this bloom may be due in part to the often hypersaline conditions in Laguna Madre (40-60 psu) that favor the growth of A. lagunensis. Above-normal rainfall in the fall of 1997 reduced the salinities in Baffin Bay from > 40 to < 20 psu. A. lagunensis cell densities dropped from > 10(6) cells ml(-1) in July 1997 to c. 200 cells ml(-1) in January 1998. During this time of low brown tide density, phytoplankton biomass generally remained high and the Laguna Madre experienced successive blooms of diatoms (Rhizosolenia spp.) and cyanobacteria. Hypersaline conditions returned in 1998 and brown tide densities increased to > 0.5 x 10(6) cells ml-1 by summer. The extraordinary persistence of the brown tide and the unusual sequence of intense blooms may be related in part to the reduction of zooplankton populations. Microzooplankton populations declined following the above-normal rain in the fail of 1997; populations did not recover until fall 1998. Copepod populations also declined sharply and remained low in Laguna Madre, but recovered by summer 1998 in Baffin Bay. Dilution experiments indicated that microzooplankton grazing and phytoplankton growth were usually balanced when measured during our cruises. The rapid recovery of the A. lagunensis bloom suggests that this alga may be a more resilient component of the Laguna Madre flora than previously suspected.