Historical Evolution of Organic Matter Accumulation in a Coastal Bay in the SW Atlantic, Brazil: Use of Sterols andn-Alcohols as Molecular Markers

Abstract

C22). Assignments of the selected markers to terrestrial or marine sources were evaluated using principal component analysis (PCA). The trends and events that influenced the OM accumulation in the last decades were also revealed by the PCA, as the increasing human settlement in the region and the removal of a mangrove forest occurred between 1940 and 1960. The absence or low level of sewage contamination was indicated by the sterol coprostanol and associated indexes.]]>

Quantification of Sterol and Triterpenol Biomarkers in Sediments of the Cananéia-Iguape Estuarine-Lagoonal System (Brazil) by UHPLC-MS/MS

“…Sterols, also known as alcohol steroids, are hydrophobic compounds that occur naturally in most of the living forms [ 1 ]. This class of compounds can be easily incorporated into sediments, where they remain well preserved, representing good tracers of sources, changes, and preservation of organic matter (OM) [ 2 ]. Sterols have been used to assess the OM origin in several estuarine systems around the world because of their recalcitrance and specific-source, which allows classifying the OM input from different sources, including terrestrial plants [ 3 ], phytoplankton [ 4 ], bacteria [ 5 ], and heterotrophic eukaryote and benthic algae [ 6 ].…”

Caracterização Da Matéria Orgânica Particulada Na Transição Baía De Guanabara Oceano Costeiro Usando Marcadores Isotópicos E Moleculares

“…Diferentes classes de lipídios como os hidrocarbonetos (Carreira et al, 2011c;Tolosa et al, 2013;Wakeham e McNichol, 2014), ácidos graxos (Close et al, 2014;Petrisic e Ogrinc, 2013;Rampen et al, 2010), esteróis (Biache e Philp, 2013;Campos et al, 2012;Rampen et al, 2010), n-álcoois (Bayona et al, 1989;Tolosa et al, 2003) e muitos outros, tem sido usados extensivamente como marcadores moleculares para avaliar as entradas de MO de origem natural e antropogênica nos ambientes costeiros mundiais. Já no Brasil, a geoquímica da MO tem sido estudada em sistemas aquáticos como estuários (Grilo et al, 2013;Martins et al, 2010;Martins et al, 2011), lagoas (Carreira et al, 2011a;Carreira et al, 2010;Martins et al, 2007;Passos et al, 2011;Silva et al, 2012), manguezais (Mater et al, 2004), baías (Mauad et al, 2013;Neto et al, 2013;Richard et al, 2014), plataforma continental (Carreira et al, 2012;Carreira et al, 2015;Kalas et al, 2009;Neto et al, 1986), entre outros. As técnicas mais utilizadas para o estudo dos lipídios biomarcadores são a cromatografia em fase gasosa com detector de ionização por chama (GC/FID) e a cromatografia em fase gasosa acoplada a espectrômetro de massas (GC/MS).…”