Natural and anthropogenic oil impacts on benthic foraminifera in the southern Gulf of Mexico
| Autor: | Patrick Schwing, A. Rodriguez-Ramírez, David J. Hollander, L. E. Gómez-Lizárraga, Adolfo Gracia, L. Almaraz-Ruiz, María Luisa Machain-Castillo, Joan-Albert Sanchez-Cabeza, H. M. Alexander-Valdés, A.C. Ruiz-Fernández, X. A. Nava-Fernández, L. H. Pérez-Bernal |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
0106 biological sciences
Geologic Sediments Foraminifera Aquatic Science Oceanography 010603 evolutionary biology 01 natural sciences Sedimentary depositional environment Ecosystem Petroleum Pollution Polycyclic Aromatic Hydrocarbons Total organic carbon Gulf of Mexico biology Terrigenous sediment 010604 marine biology & hydrobiology Trace element Sediment General Medicine Biodiversity biology.organism_classification Pollution Trace Elements Benthic zone Environmental science Water Pollutants Chemical Environmental Monitoring |
| Zdroj: | Marine environmental research. 149 |
| ISSN: | 1879-0291 |
| Popis: | The Campeche Sound is the major offshore oil producing area in the Southern Gulf of Mexico (SGoM). To evaluate the impact of oil related activities in the ocean floor sediments, we analyzed the geochemical (major and trace element, organic carbon and hydrocarbon concentrations) and biological (benthic foraminifera) composition of 62 superficial sediment samples, from 13 to 1336 m water depth. Cluster and Factor analysis of all the variables indicate that their distribution patterns are mainly controlled by differences between the terrigenous and carbonate platforms in the SGoM. Benthic foraminiferal assemblages were abundant and diverse, and their distribution patterns are mainly determined by water depth and sedimentary environment. However, most of the abundant species are opportunistic and/or low-oxygen tolerant, and many of their tests show oil stains and infillings, characteristic of oil polluted locations, suggesting the environment has been modified by natural seepage or oil-related activities. To determine if these conditions are natural or anthropogenic in origin, pre - industrial settings should be studied. Organic carbon (Corg) content (0.6–2.9%) and total hydrocarbon concentrations (PAHs 1.0–29.5 μg kg−1) were usually higher around the oil platforms area, the natural hydrocarbon seeps (“chapopoteras”) area and offshore rivers, but there is no accumulation of oil related trace elements in these areas. However, the comparison with international sediment quality benchmarks indicates that Cd, Cr and Ni concentrations are above the threshold effect level, and also As, Ba and Cu are above the probable effect level benchmarks, which indicate that these element concentrations might be of potential ecological concern. Comprehensive studies involving different proxies, and assessing pre-industrial conditions, must be undertaken before assessing environmental health of marine benthic ecosystems. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect