Spatial-Temporal Variability of the Thermohaline Properties in the Coastal Region of Fernando de Noronha Archipelago, Brazil

Spatio-temporal variation of planktonic decapods along the leeward coast of the Fernando de Noronha archipelago, Brazil

“…Other general factors that may be highlighted to explain the increase of nutrients are the sediment resuspension with the intense swell and an increment of the stools and vomiting of spinner dolphin populations that inhabit the Baía dos Golfinhos (Sazima et al, 2003). We observed a general trend of higher abundances of decapods during the rainy season in both years, coinciding with the highest levels of salinity and lower temperatures in the surface layer (Assunção et al, 2016). This pattern has also been registered for the St. Peter and St. Paul archipelago (Brandão et al, 2013).…”

“…The decrease in the phytoplankton community affects the zooplankton community (secondary consumers) directly, causing their decline (Costlow and Bookhout, 1959;Anger and Dawirs, 1981;Emmerson, 1984;Anger, 2001). Despite the higher nutrient values found at the Porto de Santo Antônio station, the amounts registered were within the expected values for oligotrophic regions (Assunção et al, 2016). It is likely that the region experiences nutrient pulses over time, as the archipelago has a large number of nesting areas for sea birds, which produce a large amount of guano fertilizer (Bosman and Hockey, 1986;Polis et al, 1997).…”

“…The nutrient level was considered normal for the oligotrophic regions of the Tropical Atlantic Ocean, with inter-annual seasonal variation (2014 with higher nutrient concentrations), though with low levels of ammonia. A sudden increase of nutrients was recorded during the rainy seasons of the two years (see Assunção et al, 2016). northern part of the island, and Cacimba do Padre (CP) and Baía dos Golfinhos (BG), located in the southern part of the island (Figure 1).…”

“…in 2014, particularly in the rainy season (Assunção et al, 2016). These results could be due to the sheltered nature of the port (hydrodynamics), or to the input of sewage from terrestrial sources (tourism), or from harbor activity (sewage from boats).…”

“…It is likely that the region experiences nutrient pulses over time, as the archipelago has a large number of nesting areas for sea birds, which produce a large amount of guano fertilizer (Bosman and Hockey, 1986;Polis et al, 1997). This guano can be transported by rain-water or washed into the sea by waves and high swell (Polis et al, 1997), thus explaining the sudden increase in the nutrient concentration in the rainy season (Assunção et al, 2016). Other general factors that may be highlighted to explain the increase of nutrients are the sediment resuspension with the intense swell and an increment of the stools and vomiting of spinner dolphin populations that inhabit the Baía dos Golfinhos (Sazima et al, 2003).…”