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@Article{LessaMJVRBAK:2019:DeHiCo,
               author = "Lessa, Douglas and Morard, Raphael and Jonkers, Lukas and 
                         Ven{\^a}ncio, Igor Martins and Reuter, Runa and Baumeister, 
                         Adrian and Albuquerque, Ana Luiza and Kucera, Michal",
          affiliation = "{University of Bremen} and {University of Bremen} and {University 
                         of Bremen} and {Instituto Nacional de Pesquisas Espaciais (INPE)} 
                         and {University of Bremen} and {University of Bremen} and 
                         {Universidade Federal Fluminense (UFF)} and {University of 
                         Bremen}",
                title = "Vertical distribution of planktonic foraminifera in the 
                         Subtropical South Atlantic: depth hierarchy of controlling 
                         factors",
              journal = "Biogeosciences Discussions",
                 year = "2019",
               volume = "2019",
               number = "355",
             abstract = "Temperature appears to be the best predictor of species 
                         composition of planktonic foraminifera communities, making it 
                         possible to use their fossil assemblages to reconstruct sea 
                         surface temperature (SST) variation in the past. However, the role 
                         of other environmental factors potentially modulating the spatial 
                         and vertical distribution of planktonic foraminifera species is 
                         poorly understood. This is especially relevant for environmental 
                         factors affecting the subsurface habitat. If such factors play a 
                         role, changes in the abundance of deeper dwelling species may not 
                         solely reflect SST variation. In order to constrain the effect of 
                         subsurface parameters on species composition, we here characterize 
                         the vertical distribution of living planktonic foraminifera 
                         community across the subtropical South Atlantic Ocean, where SST 
                         variability is small but the subsurface water mass structure 
                         changes dramatically. Four planktonic foraminifera communities 
                         could be identified across the top 700\ m of the EW 
                         transect. Gyre and Agulhas Leakage faunas were predominantly 
                         composed of Globigerinoides ruber, Globigerinoides tenellus, 
                         Trilobatus sacculifer, Globoturborotalita rubescens, 
                         Globigerinella calida, Tenuitella iota and Globigerinita 
                         glutinata, and only differed in terms of relative abundances 
                         (community composition). Upwelling fauna was dominated by 
                         Neogloboquadrina pachyderma, Neogloboquadrina incompta, 
                         Globorotalia crassaformis and Globorotalia inflata. Thermocline 
                         fauna was dominated by Tenuitella fleisheri, Globorotalia 
                         truncatulinoides and Globorotalia scitula in the western side, and 
                         by G. scitula in the eastern side of the basin. The largest part 
                         of the standing stock was consistently found in the surface layer, 
                         but SST was not the main predictor of species composition, neither 
                         for the total fauna at each station nor in analyses considering 
                         each depth layer separately. Instead, we identified a consistent 
                         vertical pattern in parameters controlling species composition at 
                         different depths, in which the parameters appear to reflect 
                         different aspects of the pelagic habitat. Whereas productivity 
                         appears to dominate in the mixed layer (060\ m), 
                         physical-chemical parameters are important at depth immediately 
                         below (60100\ m), followed by parameters related to the 
                         degradation of organic matter (100300\ m), and parameters 
                         describing the dissolved oxygen availability 
                         (>\ 300\ m). These results indicate that the 
                         seemingly straightforward relationship between assemblage 
                         composition and SST in sedimentary assemblages reflects vertically 
                         and seasonally integrated processes that are only indirectly 
                         linked to SST. This also implies that fossil assemblages of 
                         planktonic foraminifera should also contain a signature of 
                         subsurface processes, which could be used for paleoceanographic 
                         reconstructions.",
                  doi = "10.5194/bg-2019-355",
                  url = "http://dx.doi.org/10.5194/bg-2019-355",
                 issn = "1810-6277",
             language = "en",
           targetfile = "lessa_vertical.pdf",
        urlaccessdate = "19 abr. 2021"
}


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