Miocene microflora of Belorado (Spain)

Neogene deposits from Belorado (Province de Burgos, Spain) in the NE border of the Duero Basin have been analyzed. The palynologic analysis of the samples suggests the existence of arboreal landscapes associated with the herbaceous cover creating belts of vegetation around restricted aquatic areas (marshy and lacustrine environments). The characteristics of the palynomorph assemblages allow to define a warm-template climate with strong seasons. The age of these deposits could be included in the middle Miocene (Aragonian).

Seawater carbonate chemistry and dissolution rates by boring microflora during ex situ experiments with dead corals (Porites lobata), 2009

Eight-month-old blocks of the coral Porites lobata colonized by natural Hawaiian euendolithic and epilithic communities were experimentally exposed to two different aqueous pCO2 treatments, 400 ppmv and 750 ppmv, for 3 months. The chlorophyte Ostreobium quekettii dominated communities at the start and at the end of the experiment (65-90%). There were no significant differences in the relative abundance of euendolithic species, nor were there any differences in bioeroded area at the surface of blocks (27%) between pCO2 treatments. The depth of penetration of filaments of O. quekettii was, however, significantly higher under 750 ppmv (1.4 mm) than under 400 ppmv (1 mm). Consequently, rates of carbonate dissolution measured under elevated pCO2 were 48% higher than under ambient pCO2 (0.46 kg CaCO3 dissolved m2/a versus 0.31 kg /m2/a). Thus, biogenic dissolution of carbonates by euendoliths in coral reefs may be a dominant mechanism of carbonate dissolution in a more acidic ocean.