Rosales-Hoz Leticia, Carranza-Edwards Arturo, Martinez-Serrano Raymundo G, Alatorre Miguel Angel, Armstrong-Altrin John S
Instituto de Ciencias del Mar y Limnologia, Universidad Nacional Autónoma de México, 04510, Mexico, D.F., Mexico,
Environ Monit Assess. 2015 Apr;187(4):205. doi: 10.1007/s10661-015-4423-8. Epub 2015 Mar 24.
Two oceanographic cruises were taken during the winter (SAV I, November and December 2007) and summer (SAV II, July and August 2008) across the mouth of the Papaloapan River in the Gulf of Mexico. Surficial sediment samples were collected from shallow (16-30 m), intermediate (30 to 80 m), and deeper areas (≥300 m). Shallow water sediments are coarser, better-sorted, and primarily composed of sands during the winter, while those found in the summer are finer. At depths greater than 30 m, sediments are primarily fine-grained no matter the season. Major element analysis from shallow areas indicates higher SiO2 concentrations during the windy season with negative correlation against Al2O3 during both seasons, following the respective abundances of sand and muds. High organic carbon content was observed in shallow areas during the summer. Trace metals V, Ni, Cu, Zn, Pb, Li, Cr, Co, and Ba were evaluated. The first six metals showed higher average concentration in the deeper areas, although the highest values at some individual sampling sites for Cr, Co, Cu, and Ba were observed in the coastal area. Factor and cluster analysis were used to explain the sediment distribution pattern and the factors that determine the sediment characteristics within the study area. In shallow areas, four clusters were observed during the winter and five during the summer. The geochemical characteristics of the samples in each cluster suggest association with fluvial sediment input, textural characteristics, heavy minerals, and Cu and Ba concentration. To evaluate the variations in heavy metal concentration, metal enrichment factors (EFs) were calculated. Enrichment in V, Cr, Co, Zn, Ba, and Pb was detected at certain sites, whereas Cu behaved differently. The distribution of Cu enrichment suggests that it may be of natural origin, associated with the lithology of the volcanic continental area. The minor enrichment observed for other elements may be associated with river discharge. According to sediment quality guidelines, trace metal concentrations of Cu, Pb, and Zn present occasional risks to aquatic organisms.
在冬季（2007年11月和12月的SAV I）和夏季（2008年7月和8月的SAV II）期间，进行了两次海洋学考察，考察区域为墨西哥湾帕帕洛阿潘河河口。从浅水区（16 - 30米）、中间深度区（30至80米）和更深区域（≥300米）采集了表层沉积物样本。冬季浅水区沉积物较粗、分选较好，主要由沙子组成，而夏季的浅水区沉积物则较细。在深度大于30米的区域，无论季节如何，沉积物主要都是细颗粒的。浅水区的主要元素分析表明，有风季节的二氧化硅浓度较高，且在两个季节中均与氧化铝呈负相关，这与沙子和淤泥的各自丰度一致。夏季在浅水区观察到高有机碳含量。对痕量金属钒、镍、铜、锌、铅、锂、铬、钴和钡进行了评估。前六种金属在较深区域显示出较高的平均浓度，尽管在沿海地区的一些个别采样点观察到铬、钴、铜和钡的最高值。使用因子分析和聚类分析来解释沉积物分布模式以及决定研究区域内沉积物特征的因素。在浅水区，冬季观察到四个聚类，夏季观察到五个聚类。每个聚类中样本的地球化学特征表明与河流沉积物输入、质地特征、重矿物以及铜和钡的浓度有关。为了评估重金属浓度的变化，计算了金属富集因子（EFs）。在某些地点检测到钒、铬、钴、锌、钡和铅的富集，而铜的表现不同。铜富集的分布表明其可能源于自然，与火山大陆地区的岩性有关。其他元素观察到的轻微富集可能与河流排放有关。根据沉积物质量准则，铜、铅和锌的痕量金属浓度偶尔会对水生生物构成风险。
