Arévalo Raquel, Pinedo Susana, Ballesteros Enric
Centre d'Estudis Avançats de Blanes-CSIC, Accés Cala Sant Francesc 14, 17300 Blanes, Spain.
Mar Pollut Bull. 2007;55(1-6):104-13. doi: 10.1016/j.marpolbul.2006.08.023. Epub 2006 Oct 11.
Changes in the species composition and structure of Mediterranean macroalgal-dominated communities from the upper sublittoral zone are described along a gradient of nutrient enrichment coming from a urban sewage outfall. Ulva-dominated communities only appear close to the sewage outfall. Corallina-dominated communities replace ulvacean algae at intermediate levels of nutrient enrichment. Cystoseira-dominated communities thrive in the reference site but already appear at nutrient levels that are threefold higher than those reported from unpolluted sites. Assemblage variability of Cystoseira-dominated communities decreases along the gradient of nutrient enrichment. Methods based on the functional-form groups of macroalgae to assess the water quality provide equivocal results at intermediate levels of nutrient enrichment because species belonging to the same group can display a completely different response to pollution. Alternatively, methods based on indicator species showed correlated evidence among species abundances and pollution levels and seem to have better performances in water quality assessment.
本文描述了地中海大型藻类主导群落物种组成和结构的变化，该群落位于潮下带上部区域，沿着城市污水排放口产生的营养物质富集梯度分布。以石莼为主的群落仅出现在污水排放口附近。在中等营养富集水平下，以珊瑚藻为主的群落取代了石莼类藻类。以囊藻为主的群落在对照点生长旺盛，但在营养水平比未受污染地点高出三倍时就已出现。以囊藻为主的群落的组合变异性沿着营养富集梯度降低。基于大型藻类功能形态组来评估水质的方法，在中等营养富集水平下会得出模棱两可的结果，因为属于同一组的物种对污染可能表现出完全不同的反应。相比之下，基于指示物种的方法显示出物种丰度与污染水平之间的相关证据，并且在水质评估中似乎表现更好。
