Benazza Achwak, Selleslagh Jonathan, Breton Elsa, Rabhi Khalef, Cornille Vincent, Bacha Mahmoud, Lecuyer Eric, Amara Rachid
Université du littoral, UMR 8187 LOG, F-62930 Wimereux, France; Université Badji Mokhtar, Laboratoire d’Ecobiologie Milieux Marins et Littoraux, Annaba, Algeria.
Université du littoral, UMR 8187 LOG, F-62930 Wimereux, France; Université de Bordeaux, CNRS, UMR 5805 EPOC, Station Marine d’Arcachon, place du Docteur Peyneau, F-33120 Arcachon, France.
PLoS One. 2015 Jan 24;10(1):e0117220. doi: 10.1371/journal.pone.0117220. eCollection 2015.
The inter-annual variability of the fish and macrocrustacean spring community on an intertidal sandy beach near the Canche estuary (North of France) was studied from 2000 to 2013 based on weekly spring sampling over an 11-year period. Twenty-eight species representing 21 families were collected during the course of the study. The community was dominated by a few abundant species accounting for > 99% of the total species densities. Most individuals caught were young-of-the-year indicating the importance of this ecosystem for juvenile fishes and macrocrustaceans. Although standard qualitative community ecology metrics (species composition, richness, diversity, evenness and similarity) indicated notable stability over the study period, community structure showed a clear change since 2009. Densities of P. platessa, P. microps and A. tobianus decreased significantly since 2009, whereas over the period 2010-2013, the contribution of S. sprattus to total species density increased 4-fold. Co-inertia and generalised linear model analyses identified winter NAO index, water temperature, salinity and suspended particular matter as the major environmental factors explaining these changes. Although the recurrent and dense spring blooms of the Prymnesiophyte Phaeocystis globosa is one of the main potential threats in shallow waters of the eastern English Channel, no negative impact of its temporal change was detected on the fish and macrocrustacean spring community structure.
2000年至2013年期间，基于11年的每周春季采样，对法国北部康什河口附近潮间带沙滩上鱼类和大型甲壳类动物春季群落的年际变化进行了研究。在研究过程中，共采集到代表21个科的28个物种。该群落由少数优势物种主导，这些物种占总物种密度的99%以上。捕获的大多数个体为当年幼鱼，表明该生态系统对幼鱼和大型甲壳类动物具有重要意义。尽管标准的定性群落生态学指标（物种组成、丰富度、多样性、均匀度和相似度）显示在研究期间群落具有显著稳定性，但自2009年以来群落结构发生了明显变化。自2009年以来，欧洲比目鱼、小眼鲽和托氏赤虾的密度显著下降，而在2010年至2013年期间，黍鲱对总物种密度的贡献增加了4倍。共惯性分析和广义线性模型分析确定冬季北大西洋涛动指数、水温、盐度和悬浮颗粒物是解释这些变化的主要环境因素。尽管球等鞭金藻在英吉利海峡东部浅水区频繁且密集的春季水华是主要潜在威胁之一，但未检测到其时间变化对鱼类和大型甲壳类动物春季群落结构有负面影响。
