Costa Tarso de M M, Soares-Gomes Abilio
Departamento de Biologia Marinha, Universidade Federal Fluminense, P.O. Box 100.644, 24001-970 Niterói, RJ, Brazil; CE3C - Centre for Ecology, Evolution and Environmental Changes/Azorean Biodiversity Group and Universidade dos Açores, Departamento de Biologia, Ponta Delgada, Açores, Portugal.
Departamento de Biologia Marinha, Universidade Federal Fluminense, P.O. Box 100.644, 24001-970 Niterói, RJ, Brazil.
Mar Pollut Bull. 2015 Dec 30;101(2):533-8. doi: 10.1016/j.marpolbul.2015.10.061. Epub 2015 Nov 6.
Fiddler crabs Uca rapax were analyzed in three mangrove areas located in both a lagoon and estuarine system in order to study the influence of eutrophication on their population dynamics and production. Populations at the three sites showed a biased sex ratio. Densities were similar at the three sites, but biomass was higher at the lagoon system. Despite biomass being higher at the most eutrophic site, this site exhibited the lowest production. Regarding age structure, the population inhabiting the less eutrophic site mainly comprised younger crabs. The lower production and smaller P/B ratio found in the more eutrophic site were most likely consequences of a high mortality rate and an aged population. Our study evidences the high plasticity of the fiddler crab U. rapax, and confirms secondary production and P/B ratio estimates as useful tools to assess the effects of environmental change.
为了研究富营养化对招潮蟹（Uca rapax）种群动态和产量的影响，对位于泻湖和河口系统的三个红树林区域的招潮蟹进行了分析。三个地点的种群呈现出偏态的性别比例。三个地点的密度相似，但泻湖系统的生物量更高。尽管在富营养化程度最高的地点生物量更高，但该地点的产量却最低。关于年龄结构，生活在富营养化程度较低地点的种群主要由较年轻的螃蟹组成。在富营养化程度较高的地点发现的较低产量和较小的P/B比很可能是高死亡率和老龄种群的结果。我们的研究证明了招潮蟹U. rapax具有高度的可塑性，并证实次级产量和P/B比估计是评估环境变化影响的有用工具。
