Biogeosciences (BG) is an international scientific journal dedicated to the publication and discussion of research articles, short communications, and review papers on all aspects of the interactions between the biological, chemical, and physical processes in terrestrial or extraterrestrial life with the geosphere, hydrosphere, and atmosphere. The objective of the journal is to cut across the boundaries of established sciences and achieve an interdisciplinary view of these interactions. Experimental, conceptual, and modelling approaches are welcome.
We investigated an unusual ice type, called hair ice. It grows on the surface of dead wood of broad-leaf trees at temperatures slightly below 0°C.We describe this phenomenon and present our biological, physical and chemical investigations to gain insight in the properties and processes related to hair ice: we found, that a winter-acive fungus in the wood is required. Ice segregation is the common mechanism. Chemical analyses show a complex mixture of several thousand lignin/ tannin compounds.
D. Hofmann, G. Preuss, and C. Mätzler
Eleven years (2003-2013) of satellite data were processed to observe the variations in suspended particulate matter concentrations at the mouth of the Mackenzie River and estimate the fluxes exported into the Canadian Arctic Ocean. Results show that these concentrations at the river mouth, in the delta zone and in the river plume have increased by 46%, 71% and 33%, respectively, since 2003. This corresponds to a more than 50% increase in particulate export from the river into the Beaufort Sea.
D. Doxaran, E. Devred, and M. Babin
A large initial-condition ensemble suite of simulations with an Earth system model is applied to evaluate emergence characteristics of four ocean ecosystem drivers under climate change. The drivers considered are warming, acidification, deoxygenation, and perturbations to biological productivity. The spatial and temporal hierarchies of the emergence of these drivers are considered, using concepts of both time of emergence (ToE) and confidence intervals.
K. B. Rodgers, J. Lin, and T. L. Frölicher
Here we investigate how ecosystem carbon stocks vary with elevation shifting from the closed forest to open alpine tundra, in the mountains of southern Norway. Above-ground carbon stocks decreased with elevation, with a clear breakpoint at the forest line, while the organic horizon soil carbon stocks increased linearly with elevation. Overall, ecosystem carbon stocks increased with elevation above the treeline and decreased with elevation below, demonstrating the importance of the treeline.
J. D. M. Speed, V. Martinsen, A. J. Hester, Ø. Holand, J. Mulder, A. Mysterud, and G. Austrheim
We investigated the origin and mechanisms of the natural iron fertilization that sustains a phytoplankton bloom downstream of the Kerguelen Islands. We used radium isotopes to trace the fate of shelf waters that may transport iron and other micronutrients towards offshore waters. We show that shelf waters are rapidly transferred offshore and may be transported across the polar front (PF). The PF may thus not be a strong physical barrier for chemical elements released by the shelf sediments.
V. Sanial, P. van Beek, B. Lansard, M. Souhaut, E. Kestenare, F. d'Ovidio, M. Zhou, and S. Blain