UBIPRO, Facultad de Estudios Superiores Iztacala, Universidad Nacional Autónoma de México, Av. de los Barrios 1, Los Reyes Iztacala, Tlalnepantla, 54090, México, Mexico.
Departamento de Ecología Marina, Centro de Investigación Científica y de Educación Superior de Ensenada (CICESE), Carretera Ensenada-Tijuana 3918, 22860, Ensenada, Baja California, Mexico.
Environ Monit Assess. 2019 Mar 11;191(4):214. doi: 10.1007/s10661-019-7353-z.
The Jamapa-Atoyac fluvial system (JAFS) is tropical river system, which flows from the Pico de Orizaba, the highest elevation in Mexico, to end in the city of Veracruz, in the southern Gulf of Mexico. The geology of the watershed is dominated by Tertiary igneous rocks and Cretaceous limestones in the upper basin, and Quaternary alluvial sediments in the lower basin. Seventy percent of the land in the watershed has been deforested, and there are various urban and industrial areas. The JAFS is been widely known as source of trace elements to the coastal zone, and considered as contaminated. So, the aim of this study was to assess the environmental quality of the JAFS, using the total (TC) and the bioavailable (BF) concentrations of Cu and Pb, in surface fluvial sediments samples, in the dry (DS) and rainy (RS) seasons of the 2016. Average concentrations and ranges for the JAFS were Cu 10.2 ± 5.2 μg/g (2.2-41.5 μg/g); Cu 1.1 ± 1.4 μg/g (0.04-10.7 μg/g); Pb 5.0 ± 1.2 μg/g (1.8-10.9 μg/g); and Pb 0.7 ± 0.4 μg/g (0.1-2.0 μg/g). The BF only accounts for the ~ 10% of the total concentration for both elements, and is highly correlated to the mud content. No differences in average concentrations were found between the upper and lower bassins, nor among areas with different lithology. Cu presented higher concentrations during the RS, which suggest an enrichment of fluvial sediments from soil erosion, contrary, to Pb with higher concentrations during the DS. Although, some sampling stations, those located immediately after the Cordoba and Miguel Aleman cities, presented higher than average Cu and Pb concentrations, they did not exceeded the limits established by national environmental regulations, sediment quality guidelines, geoaccumulation index, and potential ecological risk indexes. Hence, the JAFS may be considered as not contaminated by Cu and Pb.
杰马帕-阿特雅克河流域（JAFS）是一条源自墨西哥最高峰皮科·德奥里萨巴的热带河流，最终流入墨西哥湾南部的韦拉克鲁斯市。流域的地质结构主要由第三纪火成岩和上流域的白垩纪石灰岩以及下流域的第四纪冲积物构成。流域内 70%的土地已经被砍伐，同时还有各种城市和工业区。JAFS 一直被认为是向沿海地区输送微量元素的源头，并被认为受到了污染。因此，本研究旨在通过评估 2016 年旱季（DS）和雨季（RS）地表河流沉积物中 Cu 和 Pb 的总量（TC）和生物有效态（BF）浓度，来评估 JAFS 的环境质量。JAFS 的平均浓度和范围分别为 Cu 10.2±5.2μg/g（2.2-41.5μg/g）；Cu 1.1±1.4μg/g（0.04-10.7μg/g）；Pb 5.0±1.2μg/g（1.8-10.9μg/g）；Pb 0.7±0.4μg/g（0.1-2.0μg/g）。BF 仅占两种元素总浓度的约 10%，且与泥含量高度相关。上、下游流域之间以及不同岩性地区之间的平均浓度没有差异。在 RS 期间，Cu 的浓度较高，这表明河流沉积物受到土壤侵蚀的富集，而 Pb 的浓度在 DS 期间较高。尽管一些采样点，如科尔多瓦和米格尔·阿莱曼市附近的采样点，Cu 和 Pb 的浓度高于平均值，但并未超过国家环境法规、沉积物质量指南、地质累积指数和潜在生态风险指数所规定的限值。因此，JAFS 可能被认为没有受到 Cu 和 Pb 的污染。
