EFFECT OF TEMPERATURE AND GRAZING ON GROWTH AND REPRODUCTION OF FLOATING MACROCYSTIS SPP. (PHAEOPHYCEAE) ALONG A LATITUDINAL GRADIENT 1
EFFECT OF TEMPERATURE AND GRAZING ON GROWTH AND REPRODUCTION OF FLOATING MACROCYSTIS SPP. (PHAEOPHYCEAE) ALONG A LATITUDINAL GRADIENT 1
复制标题
温度和放牧对漂浮大囊藻生长和繁殖的影响。
DOI：
10.1111/j.1529-8817.2009.00676.x
复制
发表时间：
2009
影响因子：
2.9
通讯作者：
M. Thiel
中科院分区：
文献类型：
--
作者：
Eva Rothäusler;I. Gómez;I. Hinojosa;U. Karsten;F. Tala;M. Thiel
大型藻筏经常漂浮在世界海洋温带地区的沿海沃茨水域。这些筏被认为是直接发展的相关生物的重要传播媒介。然而，环境因素可能会限制海带的漂浮潜力，从而限制相关生物的扩散。研究水温和放牧对浮游大囊藻生长、繁殖和存活的影响，在2006/2007年夏季，在智利太平洋沿岸沿着的三个地点（20° S、30° S、40° S），在室外水槽中进行实验。在每个研究中心，大囊藻属（Macrocystis spp.）分别在三种不同的水温（环境温度、环境温度-4 °C、环境温度+4 °C）以及存在或不存在端足类食草动物Peramphithoe femorata的情况下维持14天。 高水温（>20°C）引起大囊藻属的快速降解。木筏在中等温度（15°C-20°C）下，藻类的存活取决于相关食草动物的存在。在没有食草动物的情况下，藻筏的生物量增加，而放牧造成藻类生物量的大量损失。在较冷的条件下（<15°C），藻类的存活率最高，筏降解缓慢，食草动物引起的生物量损失通过持续的藻类生长得到补偿。我们的研究结果表明，漂浮的海带筏可以在海面上生存很长一段时间，但生存取决于温度和放牧之间的相互作用。我们认为，这些过程限制生存的海带筏在温暖的温度可能会作为一个分散的障碍海带及其相关的乘客。
Macroalgal rafts frequently occur floating in coastal waters of temperate regions of the world’s oceans. These rafts are considered important dispersal vehicles for associated organisms with direct development. However, environmental factors may limit the floating potential of kelp and thereby the dispersal of associated organisms. To examine the effect of water temperature and grazing on growth, reproductive output, and survival of floating Macrocystis spp., experiments were conducted in outdoor tanks during austral summer 2006/2007 at three sites along the Chilean Pacific coast (20° S, 30° S, 40° S). At each site, Macrocystis spp. was maintained individually at three different water temperatures (ambient, ambient − 4°C, ambient + 4°C) and in the presence or absence of the amphipod grazer Peramphithoe femorata for 14 d. High water temperatures (>20°C) provoked rapid degradation of Macrocystis spp. rafts. At moderate temperatures (15°C–20°C), algal survival depended on the presence of associated grazers. In the absence of grazers, algal rafts gained in biomass while grazing caused considerable losses of algal biomass. Algal survival was the highest under cooler conditions (<15°C), where raft degradation was slow and grazer‐induced biomass losses were compensated by continuing algal growth. Our results indicate that floating kelp rafts can survive for long time periods at the sea surface, but survival depends on the interaction between temperature and grazing. We suggest that these processes limiting the survival of kelp rafts in warmer temperatures may act as a dispersal barrier for kelp and its associated passengers.