|
|||||
|
|
Holocene Lake Level Fluctuations Recorded in the Sediment Compositionof Lake Juusa,Southeastern Estonia |
|
| Authors: | |
| Institution: | (1) Institute of Ecology at Tallinn University, Kevade 2, 10137 Tallinn, Estonia |
| Abstract: | The main aim of this study was to reconstruct the history of water level fluctuations of a small dimictic lake during the Holocene based on the lithological and geochemical composition of sediments. We studied lithological and geochemical parameters in sediment cores extracted along a transect through Lake Juusa in southeastern Estonia. Analysis revealed that LOI550 and CaCO3 content in the accumulated sediment are dependent on water depth. At depths greater than 3 m, the relationship between organic carbon and CaCO3 is inverse, whereas no relationship exists at shallower depths. Lake-level changes are well depicted on the grain-size distribution profiles and macrofossil composition. An increase in the >‰315μm fraction appeared during the initial phases of water level fluctuations, followed by an increase in the 100–315μm fraction. The >‰36μm fraction dominated the silt fraction. Higher OC/N ratios in shallow water sediments reflect the dominance of macrophytes vegetation. |
| Keywords: | Geochemistry Lake sediments Lithology Macrophytes OC/N variations Water level fluctuations |
| 本文献已被 SpringerLink 等数据库收录！ | |