Massicotte Philippe, Proulx Raphaël, Cabana Gilbert, Rodríguez Marco A
Centre de Recherche sur les Interactions Bassins Versants-Écosystèmes Aquatiques (RIVE), Université du Québec à Trois-Rivières , Trois-Rivières , Canada.
PeerJ. 2015 Feb 12;3:e760. doi: 10.7717/peerj.760. eCollection 2015.
Environmental homogenization in coastal ecosystems impacted by human activities may be an important factor explaining the observed decline in fish species richness. We used fish community data (>200 species) from extensive surveys conducted in two biogeographic provinces (extent >1,000 km) in North America to quantify the relationship between fish species richness and local (grain <10 km(2)) environmental heterogeneity. Our analyses are based on samples collected at nearly 800 stations over a period of five years. We demonstrate that fish species richness in coastal ecosystems is associated locally with the spatial heterogeneity of environmental variables but not with their magnitude. The observed effect of heterogeneity on species richness was substantially greater than that generated by simulations from a random placement model of community assembly, indicating that the observed relationship is unlikely to arise from veil or sampling effects. Our results suggest that restoring or actively protecting areas of high habitat heterogeneity may be of great importance for slowing current trends of decreasing biodiversity in coastal ecosystems.
受人类活动影响的沿海生态系统中的环境同质化可能是解释观察到的鱼类物种丰富度下降的一个重要因素。我们使用了在北美两个生物地理省份（范围>1000公里）进行的广泛调查中的鱼类群落数据（>200种），以量化鱼类物种丰富度与局部（粒度<10平方公里）环境异质性之间的关系。我们的分析基于在五年时间内从近800个站点收集的样本。我们证明，沿海生态系统中的鱼类物种丰富度在局部上与环境变量的空间异质性相关，而与其大小无关。观察到的异质性对物种丰富度的影响远大于群落组装随机放置模型模拟产生的影响，这表明观察到的关系不太可能源于面纱或采样效应。我们的结果表明，恢复或积极保护高栖息地异质性区域对于减缓当前沿海生态系统生物多样性下降的趋势可能非常重要。
