Complex interactions of climatic and ecological controls on macroalgal recruitment
Complex interactions of climatic and ecological controls on macroalgal recruitment
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DOI：
10.4319/lo.2002.47.6.1734
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发表时间：
2002-11-01
影响因子：
4.5
通讯作者：
Worm, B
中科院分区：
文献类型：
--
作者：
Lotze, HK;Worm, B
关于多重（>2）环境控制对水生生态系统中物种表现和相互作用的累积效应知之甚少。我们询问了气候（温度、紫外线辐射）和生态控制（营养、放牧）的变化如何影响绿色大型浮游植物浒苔的补充，这种藻类在全球沿海生态系统中形成破坏性的藻华。我们设计了析因实验室实验来分析补充对（1）营养富集、放牧压力和食草动物物种组成的单一和综合影响以及（2）紫外线（UV）辐射、温度、营养和放牧的累积影响的反应。招募E。随着营养物质的富集，生物量呈指数增长。食草动物可以控制藻类的招聘，直到营养阈值达到取决于食草动物物种组成。蜗牛（Littorina littorea）有很强的负效应，招募密度，而端足类动物（Gaminarlis oceanicus）有弱放牧效应，有利于藻类招聘时，营养供应低，通过排泄。温度和营养盐都增强了藻类的补充，但也有食草动物的影响，这导致了这些因素之间的显着的三向交互作用。同样，紫外线辐射的影响取决于食草动物的存在和温度。当食草动物缺席，紫外线辐射减少招聘在11和17 ℃，但增强招聘在5 ℃。在食草动物存在的情况下没有观察到任何影响。我们的研究结果表明，多种人为影响，如气候变化，富营养化和食物网的改变，具有相互依存的影响和协同提高沿海生态系统中大型藻类水华的发展潜力。
Little is known about the cumulative effects of multiple (>2) environmental controls on species performance and interactions in aquatic ecosystems. We asked how changes in climatic (temperature, ultraviolet radiation) and ecolouical controls (nutrients, grazing) affect recruitment of the green macroalga Enteromorpha intestinalis, which forms destructive algal blooms in coastal ecosystems worldwide. We designed factorial laboratory experiments to analyze the recruitment response to (1) single and combined effects of nutrient enrichment, grazing pressure, and grazer species composition and (2) the cumulative effects of ultraviolet (UV) radiation, temperature, nutrients, and grazing. Recruitment of E. intestinalis increased exponentially with nutrient enrichment. Grazers could control algal recruitment until a nutrient threshold was reached depending on grazer species composition. Snails (Littorina littorea) had strong negative effects on recruit density, whereas amphipods (Gaminarlis oceanicus) had weak grazing effects and favored algal recruitment through excretion when nutrient supply was low. Temperature and nutrients both enhanced algal recruitment but also the effects of grazers, which led to a significant three-way interaction among these factors. Similarly, effects of UV radiation depended on grazer presence and temperature. When grazers were absent, UV radiation reduced recruitment at 11 and 17degreesC but enhanced recruitment at 5degreesC. No effects were seen in the presence of grazers. Our results indicate that multiple human influences, such as climate change, eutrophication, and food web alterations, have interdependent effects and the potential for synergistically enhancing the development of macroalgal blooms in coastal ecosystems.