Factors influencing particulate lipid production in the East Atlantic Ocean

Abstract

a b s t r a c tExtensive analyses of particulate lipids and lipid classes were conducted to gain insight into lipid production and related factors along the biogeochemical provinces of the Eastern Atlantic Ocean. Data are supported by particulate organic carbon (POC), chlorophyll a (Chl a), phaeopigments, Chl a concentrations and carbon content of eukaryotic micro-, nano-and picophytoplankton, including cell abundances for the latter two and for cyanobacteria and prokaryotic heterotrophs. We focused on the productive ocean surface (2 m depth and deep Chl a maximum (DCM)). Samples from the deep ocean provided information about the relative reactivity and preservation potential of particular lipid classes. ) where an increased contribution to the POC pool was observed. The highest lipid concentrations were measured in high latitude temperate waters and in the North Atlantic Tropical Gyral Province (13-251N). Factors responsible for the enhanced lipid synthesis in the eastern Atlantic appeared to be phytoplankton size (micro, nano, pico) and the low nutrient status with microphytoplankton having the most expressed influence in the surface and eukaryotic nano-and picophytoplankton in the DCM layer. Higher lipid to Chl a ratios suggest enhanced lipid biosynthesis in the nutrient poorer regions. The various lipid classes pointed to possible mechanisms of phytoplankton adaptation to the nutritional conditions. Thus, it is likely that adaptation comprises the replacement of membrane phospholipids by non-phosphorus containing glycolipids under low phosphorus conditions. The qualitative and quantitative lipid compositions revealed that phospholipids were the most degradable lipids, and their occurrence decreased with increasing depth. In contrast, wax esters, possibly originating from zooplankton, survived downward transport probably due to the fast sinking rate of particles (fecal pellets). The important contribution of glycolipids in deep waters reflected their relatively stable nature and degradation resistance. A lipid-based proxy for the lipid degradative state (Lipolysis Index) suggests that many lipid classes were quite resistant to degradation even in the deep ocean.

Phospholipids as a component of the oceanic phosphorus cycle

“…8b). Lipids, like bulk POC, are produced primarily in surface waters by plankton and are largely recycled and degraded in sub-surface waters (Gašparović et al, 2014;Wakeham, 1995). Size-fractionated…”

“…Particulate PL concentrations in the northern Adriatic, Mediterranean, throughout a year vary in the range of 3.0 to 27.7 µg/l, with a contribution to total lipids between 17.8 and 50.3% (Frka et al, 2011;Marić et al, 2013) as measured by thin layer chromatography. PL in the oligotrophic to mesotrophic region of the east Atlantic, measured by thin layer chromatography, ranged from 1.3 to 7.8 µg/l, contributing between 11.4 and 55.0% of total lipid content (Gašparović et al, 2014). In the upper 250 m of the oceanic water column, concentrations of measured PL (PG+PE+PC) in the eastern subtropical South Pacific ranged between 130-1350 pmol/l (Van Mooy and Fredrichs, 2010).…”

Insights into the life strategy of the common marine diatom Chaetoceros peruvianus Brightwell

“…Total lipid concentrations were obtained by summing all lipid classes quantified by TLC-FID. A detailed description of the procedure is described in Gašparović et al [ 21 , 35 , 36 ].…”

Concerted measurements of lipids in seawater and on submicrometer aerosol particles at the Cabo Verde islands: biogenic sources, selective transfer and high enrichments

“…Until now, lipids or individual lipid classes have often been analyzed in only one compartment of the ambient marine environment, i.e., seawater or marine aerosol particles (Gagosian et al, 1982;Simoneit and Mazurek, 1982;Frka et al, 2011;Gašparović et al, 2014). The possible transfer of total lipids (determined as a sum parameter) has so far only been described under controlled conditions in laboratory studies (Rastelli et al, 2017) or for certain lipid classes such as fatty acids, n-alkanes, total hydrocarbons (Marty et al, 1979), or as fatty acids and their derivatives (Cochran et al, 2016b) in freshly emitted sea spray aerosol.…”