Dynamics of physicochemical variables of the northern Colombian Caribbean coastal waters

Abstract

This study explored oceanographic dynamics related to high productivity processes in the northern Colombian Caribbean. Four scientific expeditions were carried out between May and December 2018, where selected physicochemical variables were measured using a CTDO (conductivity, temperature and dissolved oxygen sensor system), and transparency with a Secchi disc. May and December showed typical upwelling waters, while August and November showed waters characteristic of the rainy season. Spatial dynamics were related to temperature and salinity. Thus, northeastern stations showed colder and saltier surface waters compared to those located to the southwest. Vertical readings were taken and the Caribbean Surface Water mass was identified, and below it the subtropical subsurface water mass, which emerges at the beginning of the year. The results suggest that upwelling and freshwater runoff have a direct impact on the hydrographic structure of the region.

Seasonal upwelling conditions promote growth and calcification in reef‐building coralline algae

“…It is likely that the nutrient‐enriched upwelling waters favored a number of processes in the CCA in our study site, but further studies are needed to explore this relationship in detail. We were unable to collect data on irradiance in our study, but existing data sets from the same region generally show higher water transparency and irradiance (and lower sedimentation) values during the upwelling compared to the rainy season (Diaz‐Pulido & Garzón‐Ferreira, 2002; Eidens et al, 2012; Vega‐Sequeda et al, 2019). Since light availability (and sediment accumulation) is critical for CCA physiological processes (e.g., Caragnano et al, 2014; Fabricius & De´ath, 2001; Freiwald & Henrich, 1994; Steneck, 1997; Vásquez‐Elizondo & Enríquez, 2016), increased light availability may have favored CCA performance during the upwelling season.…”

“…Upwelling in the region is induced by an increase in the intensity and change in direction of the trade winds, which induce the upwelling of subsurficial waters (Arévalo‐Martínez & Franco‐Herrera, 2006; Paramo et al, 2011; Vega‐Sequeda et al, 2019). During the study period, upwelling was characterized by lower sea surface temperature (min: 23.14 ± 0.6°C), lower pH (8.0 and 8.2), and higher nitrate (NO 3 − ) concentration (max: 2.06 μg‐at N · L −1 ) than those during the non‐upwelling periods (Figure 2).…”

Changes in mercury content in oysters in relation to sediment and seston content in the Colombian Caribbean lagoons

“…The Colombian Caribbean region is characterized by a bimodal climatic regime with a rainy and dry season in uenced by the Intertropical Convergence Zone (ITCZ) that generates periodic patterns [13]. Trade winds predominate from December to April (dry season), changing direction to the southeast between April and November (rainy season) [14].…”

Exploring the Status of an Urban Coral and the Presence of Potential Probiotic Traits in Culturable Bacteria

“…The dry season (December-April) is characterized by cold waters ranging from 20 C (max) and salinity > 36; and the rainy season (May-November) is characterized by warmer waters between 27 • C (min) and 29 • C (max) and salinity < 34 [43,44]. The high discharges from the submarine outfall, the local rivers, the overflow of sewers, and the Magdalena River and Cienega Grande de Santa Marta (CGSM) affect the quality of the coastal waters, increasing nutrients, sedimentation, algae biomass, and bacterial load [44][45][46]. This area harbors several coral reef formations (typically patchy).…”