Popis: |
The acid resistant microscopic organic matter preserved in marine sediments (palynofacies) represents a small fraction of marine and terrestrial biomass that escaped rapid degradation and recycling to the atmospheric and hydrospheric carbon reservoirs. Palynofacies consists of (1) organic microfossils (palynomorphs), (2) fragments of larger organic structures (palynodebris), and (3) degradation products of both debris and palynomorphs (diffuse organic aggregates). Palynofacies composition is biologically, chemically and physically determined by the combined selective effects of (1) qualitative and quantitative composition of source biomass, (2) chemical preservation potential of individual biomacromolecular structures in organic remains during sedimentation and diagenesis, and (3) a wide variety of external chemical and physical conditions, such as water currents, sedimentation rate, oxygen level, and temperature. Complementary to biogeochemical analysis, the palynological analysis of organic matter constituents from (sub)recent sediment samples can provide insight in (1) the biological affinity of individual palynofacies categories, and (2) the influence of differential sorting and differential degradation on palynofacies composition. |