Rodriguez César Augusto B, Bezerra Moises F, Rezende Carlos Eduardo DE, Bastos Wanderley R, Lacerda Luiz D DE
Laboratório de Biogeoquímica Costeira, Instituto de Ciências do Mar, Universidade Federal do Ceará, Av. Abolição, 3207, 60165-081 Fortaleza, CE, Brazil.
Department of Biology, San Diego State University, 92182-4614, San Diego, CA, USA.
An Acad Bras Cienc. 2019 Jul 10;91(2):e20180672. doi: 10.1590/0001-3765201920180672.
The present work tests the use of carapace fragments of the marine turtle Caretta caretta as a tool for environmental biomonitoring of mercury (Hg) and to evaluate the influence of biological and ecological factors in Hg concentrations. Samples of carapace fragments were obtained during the nesting season of 2012 and 2016 and were analyzed for their total-Hg and methyl-Hg concentrations and the isotopic composition of carbon and nitrogen (δ15N and δ13C). Seventy-six females were sampled, with an average size of 87.1 to 107 cm of curved carapace length (CCL). The results showed a wide variation in total Hg concentrations (3.3 - 1,672 ng g-1) and low concentrations of methyl-Hg, not showing any pattern of accumulation among the individuals. The isotopic composition of δ15N and δ13C suggests that the individuals sampled belong to a high trophic level but did not present any relationship with the Hg concentrations. It suggests that, at least with the existing results, and unlike other turtle species, carapace fragments of C. caretta cannot yet be used in environmental monitoring.
本研究测试了蠵龟（Caretta caretta）的背甲碎片作为汞（Hg）环境生物监测工具的用途，并评估了生物和生态因素对汞浓度的影响。在2012年和2016年的筑巢季节采集了背甲碎片样本，分析了它们的总汞和甲基汞浓度以及碳和氮的同位素组成（δ15N和δ13C）。共采集了76只雌性样本，其弯曲背甲长度（CCL）平均为87.1至107厘米。结果显示，总汞浓度差异很大（3.3 - 1,672 ng g-1），甲基汞浓度较低，个体之间未呈现出任何积累模式。δ15N和δ13C的同位素组成表明，所采集的个体属于高营养级，但与汞浓度没有任何关系。这表明，至少就现有结果而言，与其他龟类物种不同，蠵龟的背甲碎片目前还不能用于环境监测。
