RESUMEN
Pelagic Sargassum in the Gulf of Mexico (GoM) plays an important role in ocean biology and ecology, yet our knowledge of its origins and transport pathways is limited. Here, using satellite observations of Sargassum areal density and ocean surface currents between 2000 and 2023, we show that large amounts of Sargassum in the GoM can either originate from the northwestern GoM or be a result of physical transport from the northwestern Caribbean Sea, both with specific transport pathways. Sargassum of the northwestern GoM can be transported to the eastern GoM by ocean currents and eddies, eventually entering the Sargasso Sea. Sargassum entering the GoM from the northwestern Caribbean Sea can be transported in three different directions, with the northward and eastward transports governed by the Loop Current System (LCS) and westward transport driven by the westward extension of the LCS, the propagation or relaying of ocean eddies, the wind-driven westward currents on the Campeche Bank with or without eddies, and the westward currents with/without currents associated with eddies in the northern/central GoM. Overall, the spatial distribution patterns of pelagic Sargassum in the GoM are strongly influenced by the LCS and relevant eddies.
Asunto(s)
Sargassum , Golfo de México , Ambiente , Región del Caribe , EcologíaRESUMEN
The northern Gulf of Mexico (GoM) is a region strongly influenced by river discharges of freshwater and nutrients, which promote a highly productive coastal ecosystem that host commercially valuable marine species. A variety of climate and weather processes could potentially influence the river discharges into the northern GoM. However, their impacts on the coastal ecosystem remain poorly described. By using a regional ocean-biogeochemical model, complemented with satellite and in situ observations, here we show that El Niño - Southern Oscillation (ENSO) is a main driver of the interannual variability in salinity and plankton biomass during winter and spring. Composite analysis of salinity and plankton biomass anomalies shows a strong asymmetry between El Niño and La Niña impacts, with much larger amplitude and broader areas affected during El Niño conditions. Further analysis of the model simulation reveals significant coastal circulation anomalies driven by changes in salinity and winds. The coastal circulation anomalies in turn largely determine the spatial extent and distribution of the ENSO-induced plankton biomass variability. These findings highlight that ENSO-induced changes in salinity, plankton biomass, and coastal circulation across the northern GoM are closely interlinked and may significantly impact the abundance and distribution of fish and invertebrates.
RESUMEN
Los aptámeros son ácidos nucleicos de cadena sencilla, ADN o ARN, que reconocen una gran variedad de moléculas. Cada aptámero posee una estructura tridimensional particular que le permite unirse con afinidad y especificidad altas a la molécula diana. Los aptámeros tienen propiedades de reconocimiento equiparables a las de los anticuerpos; sin embargo, por la naturaleza de su composición tienen ventajas significativas en cuanto a su tamaño, producción y modificación. Estas características los hacen excelentes candidatos para el desarrollo de nuevas plataformas biotecnológicas. Se han identificado aptámeros con propiedades terapéuticas que han sido evaluados exitosamente en modelos animales; entre ellos, algunos se encuentran en fase clínica y uno ya fue aprobado para tratamiento por la FDA (Food and Drug Administration). Todos estos avances ocurridos durante las dos últimas décadas permiten anticipar el protagonismo que tendrán los aptámeros como agentes diagnósticos y terapéuticos en un futuro cercano.
Aptamers are single-stranded DNA or RNA molecules that recognize a variety of target molecules with high levels of affinity and specificity, due to their particular three-dimensional structure. They are similar to antibodies regarding the recognition process. However, they offer significant advantages over antibodies based on their size, ease of production and various chemical modifications. Thus, they are excellent candidates for developing new biotechnological platforms. Up to date, several aptamers with therapeutic properties have been successfully evaluated in animal models and clinical trials. Moreover, one of them has already been approved by the FDA. Advances during the last two decades allow to foresee that aptamers will play a key role as diagnostic and therapeutic agents in the near future.