0000000000289390
AUTHOR
Rob Witbaard
The revolution of crossdating in marine palaeoecology and palaeoclimatology.
Over the past century, the dendrochronology technique of crossdating has been widely used to generate a global network of tree-ring chronologies that serves as a leading indicator of environmental variability and change. Only recently, however, has this same approach been applied to growth increments in calcified structures of bivalves, fish and corals in the world's oceans. As in trees, these crossdated marine chronologies are well replicated, annually resolved and absolutely dated, providing uninterrupted multi-decadal to millennial histories of ocean palaeoclimatic and palaeoecological processes. Moreover, they span an extensive geographical range, multiple trophic levels, habitats and f…
Environmental and biological factors influencing trace elemental and microstructural properties of Arctica islandica shells
Long-term and high-resolution environmental proxy data are crucial to contextualize current climate change. The extremely long-lived bivalve, Arctica islandica, , is one of the most widely used paleoclimate archives of the northern Atlantic because of its fine temporal resolution. However, the interpretation of environmental histories from microstructures and elemental impurities of A. islandica, shells is still a challenge. Vital effects (metabolic rate, ontogenetic age, and growth rate) can modify the way in which physiochemical changes of the ambient environment are recorded by the shells. To quantify the degree to which microstructural properties and element incorporation into A. island…
Accurate increment identification and the spatial extent of the common signal in fiveArctica islandicachronologies from the Fladen Ground, northern North Sea
[1] The creation of networks of shell-based chronologies which can provide regionally extensive high-resolution proxies for the marine environment depends on the spatial extent of the common environmental signal preserved in the shell banding and on the reliability of the dating model. Here Arctica islandica chronologies from five neighboring sites in the North Sea are compared, and the strength of the common environmental signal across distances up to 80 km is analyzed using statistical techniques derived from dendrochronology. The signal is found to be coherent across these distances. In a linked study, chronologies based on one of the same sites but constructed by two different research …
Changes of shell microstructural characteristics of Cerastoderma edule (Bivalvia) — A novel proxy for water temperature
Abstract Shells of bivalves potentially provide an excellent archive for high-resolution paleoclimate studies. However, quantification of environmental variables, specifically water temperature remains a very challenging task. Here, we explore the possibility to infer water temperature from changes of microstructural characteristics of shells of the common cockle, Cerastoderma edule . The size and elongation of individual microstructural units, i.e., prisms, in the outer shell layer of seven three to five year-old, specimens collected alive from the intertidal zone of the North Sea near Texel, The Netherlands, and Schillig, Germany, were measured by means of automatic image processing. Grow…