Inhaltszusammenfassung

Age-detrended and standardized annual growth increment width time series of 67 live-collected intertidal bivalve molluscs of the species Chione cortezi, C. fluctifraga and C. californiensis from the northern Gulf of California were strung together to form a master-chronology that covers the period from AD 1982 to 1999. A high positive correlation was found between standardized annual growth rates and summer sea-surface temperatures and river-flow volume in the period 1988-99; and 63-76% of th...Age-detrended and standardized annual growth increment width time series of 67 live-collected intertidal bivalve molluscs of the species Chione cortezi, C. fluctifraga and C. californiensis from the northern Gulf of California were strung together to form a master-chronology that covers the period from AD 1982 to 1999. A high positive correlation was found between standardized annual growth rates and summer sea-surface temperatures and river-flow volume in the period 1988-99; and 63-76% of the variation in mean relative annual growth rates of Chione spp. is explained by temperature and river flow. Seven dead-collected specimens were cross-dated with the master-chronology permitting the reconstruction of the year of hatching and death for these shells. The incorporation of dead-collected specimens in the master-chronology improved the correlation statistics slightly. Species-related growth differences were not significant, but geographic differences in growth rates occur: individuals at the Colorado River mouth grew more slowly when large amounts of fresh water reached the Gulf. This study demonstrates that even short-lived molluscs (average 6-10 years old) can be used to build a master-chronology of environmental and climatic history.» weiterlesen» einklappen

Autoren

Klassifikation

DFG Fachgebiet:
3.31 - Mathematik

DDC Sachgruppe:
Paläontologie