ISSN:
1573-0417
Keywords:
δ13C organic
;
glacial-interglacial cycles
;
mass accumulation rates
;
C/N ratios
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Geosciences
Notes:
Abstract A 911-m-long sediment core from Lake Biwa, Japan, provides a record of organic matter delivery and accumulation in this large lake during a succession of tectonic and climatic changes dating back to the latest Pliocene. Sediments deposited since 430 ky are profundal; older sediments vary in setting between shallow-water and fluviodeltaic conditions, with occasional deep-water intervals. C/N ratios identify algal production as the dominant source of organic matter throughout the core, although the proportion of land-derived contributions episodically increases in the fluviodeltaic and shallow-water sediments. Rates of organic matter delivery and burial in lake sediments change in response to glacial-interglacial climate changes over the past 430 ky. Sediments deposited during interglacial intervals have organic carbon mass accumulation rates up to 9 times greater than those from glacial intervals, reflecting interglacial climates that were wetter than glacial climates. Algal production of organic matter increased during interglacial times because of greater wash-in of soil nutrients, and organic matter preservation was enhanced because of faster sedimentation rates.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1007913901723
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