Contente Riguel Feltrin, Del Bianco Rossi-Wongtschowski Carmen Lucia
Departamento de Oceanografia Biológica, Instituto Oceanográfico, Universidade de São Paulo, São Paulo, Brazil.
Programa de Pós-Graduação em Sistemas Costeiros e Oceânicos (PGSISCO), Centro de Estudos do Mar, Universidade Federal do Paraná, Pontal do Paraná, Brazil.
Environ Monit Assess. 2017 Jun;189(6):251. doi: 10.1007/s10661-017-5954-y. Epub 2017 May 4.
The use of multiple sampling gears is indispensible to obtain robust characterizations of fish assemblage structure in species-rich subtropical ecosystems. In this study, such a dependence was demonstrated by characterizing the structure of the high-tide fish assemblage in a subtropical tidal flat ecosystem (the Araçá Bay, southeastern Brazil) using eight different gears along five seasonal surveys and estimating the bay's fish species richness, combining these data with those from local tide pool fish surveys. The high-tide fish assemblage was spatially structured, contained five threatened species, and was dominated by persistent and large populations of Eucinostomus argenteus and of the fisheries species Mugil curema and Diapterus rhombeus that intensively use the bay throughout their life cycles. Large, small-bodied fish populations supported a regular use of the bay by piscivores. The autumn-winter peak in abundance of juvenile fishes caused a subsequent increase in piscivore abundance, and both events explained the bulk of the seasonal variability of the fish assemblage. The estimated richness revealed that the combination of sampling methods was enough for sampling the bulk of the local richness, and the bay may hold a surprisingly high richness compared to other costal ecosystem of the region. This faunal characterization, only viable using multiple gears, will be critical to support the implementation of a future study to monitor the impacts on local fish biodiversity of an imminent port expansion over the tidal flat.
在物种丰富的亚热带生态系统中，使用多种采样工具对于获得鱼类群落结构的可靠特征至关重要。在本研究中，通过在五个季节调查中使用八种不同工具对亚热带潮间带生态系统（巴西东南部的阿拉卡湾）的高潮位鱼类群落结构进行特征描述，并估计该湾的鱼类物种丰富度，将这些数据与当地潮池鱼类调查的数据相结合，证明了这种依赖性。高潮位鱼类群落具有空间结构，包含五种受威胁物种，并且在整个生命周期中大量密集利用该湾的银口油鲱、渔业物种鲻鱼和菱体蝴蝶鱼的持久且大量的种群占主导地位。大量小型鱼类种群为食鱼动物定期利用该湾提供了支持。幼鱼数量在秋冬季节达到峰值，随后导致食鱼动物数量增加，这两个事件解释了鱼类群落季节性变化的主要部分。估计的丰富度表明，采样方法的组合足以对当地大部分丰富度进行采样，并且与该地区的其他沿海生态系统相比，该湾可能拥有惊人的高丰富度。这种仅通过使用多种工具才可行的动物区系特征描述，对于支持未来一项监测即将在潮间带进行的港口扩张对当地鱼类生物多样性影响的研究的实施至关重要。
