@article{TitschackBaumDePolHolzetal., author = {Titschack, J{\"u}rgen and Baum, Daniel and De Pol-Holz, Ricardo and L{\´o}pez Correa, Matthias and Forster, Nina and Fl{\"o}gel, Sascha and Hebbeln, Dierk and Freiwald, Andr{\´e}}, title = {Aggradation and carbonate accumulation of Holocene Norwegian cold-water coral reefs}, series = {Sedimentology}, volume = {62}, journal = {Sedimentology}, number = {7}, publisher = {Wiley}, doi = {10.1111/sed.12206}, pages = {1873 -- 1898}, language = {en} } @article{FaerberTitschackSchoenbergetal., author = {F{\"a}rber, Claudia and Titschack, J{\"u}rgen and Sch{\"o}nberg, Christine H. L. and Ehrig, Karsten and Boos, Karin and Baum, Daniel and Illerhaus, Bernd and Asgaard, Ulla and Bromley, Richard G. and Freiwald, Andr{\´e} and Wisshak, Max}, title = {Long-term macrobioerosion in the Mediterranean Sea assessed by micro-computed tomography}, series = {Biogeosciences}, volume = {13}, journal = {Biogeosciences}, number = {11}, address = {http://www.biogeosciences.net/13/3461/2016/}, doi = {10.5194/bg-13-3461-2016}, pages = {3461 -- 3474}, abstract = {Biological erosion is a key process for the recycling of carbonate and the formation of calcareous sediments in the oceans. Experimental studies showed that bioerosion is subject to distinct temporal variability, but previous long-term studies were restricted to tropical waters. Here, we present results from a 14-year bioerosion experiment that was carried out along the rocky limestone coast of the island of Rhodes, Greece, in the Eastern Mediterranean Sea, in order to monitor the pace at which bioerosion affects carbonate substrate and the sequence of colonisation by bioeroding organisms. Internal macrobioerosion was visualised and quantified by micro-computed tomography and computer-algorithm-based segmentation procedures. Analysis of internal macrobioerosion traces revealed a dominance of bioeroding sponges producing eight types of characteristic Entobia cavity networks, which were matched to five different clionaid sponges by spicule identification in extracted tissue. The morphology of the entobians strongly varied depending on the species of the producing sponge, its ontogenetic stage, available space, and competition by other bioeroders. An early community developed during the first 5 years of exposure with initially very low macrobioerosion rates and was followed by an intermediate stage when sponges formed large and more diverse entobians and bioerosion rates increased. After 14 years, 30 \% of the block volumes were occupied by boring sponges, yielding maximum bioerosion rates of 900 g m^-2 yr^-1. A high spatial variability in macrobioerosion prohibited clear conclusions about the onset of macrobioerosion equilibrium conditions. This highlights the necessity of even longer experimental exposures and higher replication at various factor levels in order to better understand and quantify temporal patterns of macrobioerosion in marine carbonate environments.}, language = {en} } @article{TitschackFinkBaumetal., author = {Titschack, J{\"u}rgen and Fink, Hiske G. and Baum, Daniel and Wienberg, Claudia and Hebbeln, Dierk and Freiwald, Andr{\´e}}, title = {Mediterranean cold-water corals - an important regional carbonate factory?}, series = {The Depositional Record}, volume = {2}, journal = {The Depositional Record}, number = {1}, doi = {10.1002/dep2.14}, pages = {74 -- 96}, language = {en} } @article{MatsuyamaTitschackBaumetal.2015, author = {Matsuyama, Kei and Titschack, J{\"u}rgen and Baum, Daniel and Freiwald, Andr{\´e}}, title = {Two new species of erect Bryozoa (Gymnolaemata: Cheilostomata) and the application of non-destructive imaging methods for quantitative taxonomy}, series = {Zootaxa}, volume = {4020}, journal = {Zootaxa}, number = {1}, doi = {10.11646/zootaxa.4020.1.3}, pages = {81 -- 100}, year = {2015}, abstract = {Two new species of cheilostome Bryozoa are described from continental-slope habitats off Mauritania, including canyon and coldwater-coral (mound) habitats. Internal structures of both species were visualised and quantified using micro-computed tomographic (micro-CT) methods. Cellaria bafouri n. sp. is characterised by the arrangement of zooids in alternating longitudinal rows, a smooth cryptocyst, and the presence of an ooecial plate with denticles. Smittina imragueni n. sp. exhibits many similarities with Smittina cervicornis (Pallas, 1766), but differs especially in the shape and orientation of the suboral avicularium. Observations on Smittina imragueni and material labelled as Smittina cervicornis suggest that the latter represents a species group, members of which have not yet been discriminated, possibly because of high intracolony variation and marked astogenetic changes in surface morphology. Both new species are known only from the habitats where they were collected, probably reflecting the paucity of bryozoan sampling from this geographic area and depth range. Both species are able to tolerate low oxygen concentration, which is assumed to be compensated by the high nutrient supply off Mauritania. The application of micro-CT for the semiautomatic quantification of zooidal skeletal characters was successfully tested. We were able to automatically distinguish individual zooidal cavities and acquire corresponding morphological datasets. Comparing the obtained results with conventional SEM measurements allowed ascertaining the reliability of this new method. The employment of micro-CT allows the observation and quantification of previously un- seen characters that can be used in describing and differentiating species that were previously indistinguishable. Further- more, this method might help elucidate processes of colony growth and the function of individual zooids during this process.}, language = {en} }