Combined use of aerogammaspectrometry and geochemistry to access sediment sources in a shallow coral site at Armação dos Búzios, Brazil

• Published in: Estuarine, coastal and shelf science Vol. 87; no. 4; pp. 526 - 534
• Main Authors: Godiva, Danielly, Evangelista, Heitor, Kampel, Milton, Licinio, Marcus Vinicius, Munita, Casimiro
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 20-05-2010; Elsevier
• Subjects: aerogammaspectrometry; Animal and plant ecology; Animal, plant and microbial ecology; Armação dos Búzios; Biological and medical sciences; Brackish; Brackish water ecosystems; Cnidaria. Ctenaria; Coastal; Corals; Fundamental and applied biological sciences. Psychology; Geochemistry; Human; Invertebrates; Marine; radioisotopes; River basins; Sedimentation; Sediments; Siderastrea stellata; Synecology; South America; Brazil; America; Bosnia-Herzegovina, Una R; AS, South Atlantic; Brazil, Macae R; Brazil, Macae R. basin; aerogammaspectrometry; radioisotopes; Armação dos Búzios; siderastrea stellata; sedimentation; Brackish water environment; Geochemistry; Radioisotope; Sediments; Sedimentation; Coelenterata; Coral; Cnidaria; Invertebrata
• ISSN: 0272-7714; 1096-0015
• DOI: 10.1016/j.ecss.2010.02.006

Coral and reef environments in shallow waters are negatively affected by human activities in several coastal areas worldwide. It has been demonstrated that sediment influx and macronutrient discharges induce decline of coral population structure and diversity. Therefore, efforts to quantify sediment flux, sources and the biological response to sedimentation were conducted by several marine researchers. Herein, we investigated the case study of Armação dos Búzios/Brazil/Western South Atlantic, where coral colonies (mostly
Siderastrea stellata) are under stress due to sediment apportionment as a consequence of regional human occupation. Classification of potential sediment source regions was based on a high-resolution aerogammaspectrometry survey for
232Th,
238U and
40K in main land near shore, used as primarily tool, in combination with sediment geochemistry. This approach allowed distinguishing three hydrographic basins (Macaé river basin, São João river basin and Una river basin) as potential sources. Hierarchical cluster analysis applied to the set of parameters identified the Macaé River as the most probable sediment contributor to the coralline site.