Trace elements and organochlorines in the shoalgrass community of the lower Laguna Madre Texas

T. W. Custer; C. A. Mitchell

doi:10.1007/bf00548024

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Trace elements and organochlorines in the shoalgrass community of the lower Laguna Madre Texas

T. W. Custer·C. A. Mitchell

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Abstract

Our objectives were to measure concentrations of seven trace elements and 14 organochlorine compounds in sediment and biota of the shoalgrass ( Halodule wrightii ) community of the lower Laguna Madre of south Texas and to determine whether chemicals associated with agriculture (e.g. mercury, arsenic, selenium, organochlorine pesticides) were highest near agricultural drainages. Arsenic, mercury, selenium, lead, cadmium, and organochlorines were generally at background concentrations throughout the lower Laguna Madre. Nickel and chromium concentrations were exceptionally high in shrimp and pinfish ( Lagodon rhomboides ), which is difficult to explain because of no known anthropogenic sources for these trace elements. For sediment and blue crabs ( Callinectes sapidus ), mercury was highest near agricultural drainages. Also, DDE was more frequently detected in blue crabs near agricultural drainages than farther away. In contrast, selenium concentrations did not differ among collecting sites and arsenic concentrations were lowest in shoalgrass, blue crabs, and brown shrimp ( Penaeus aztecus ) near agricultural drainages.

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Environmental Monitoring and Assessment Article

Source-reported bounding extent: 26.054315442680412° to 26.556593211456345° latitude; -97.4322509765625° to -97.15347290039061° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeX RIS

T. W. Custer, C. A. Mitchell. 1993. Trace elements and organochlorines in the shoalgrass community of the lower Laguna Madre Texas. https://doi.org/10.1007/bf00548024

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