A 13-m long sediment core from Borsog Bay of Lake Khuvsgul,northern Mongolia records hydro-environmental changes during the past 10000 years;three rapid environmental changes(ca.2700 a BP,ca.6000 a BP and ca.8000 a BP...A 13-m long sediment core from Borsog Bay of Lake Khuvsgul,northern Mongolia records hydro-environmental changes during the past 10000 years;three rapid environmental changes(ca.2700 a BP,ca.6000 a BP and ca.8000 a BP based on ^(14)C dates of organic carbon materials) are detected in depth profiles of sediment physical properties.Temporal changes in the physical properties of the core(grain size,grain density and water content) also suggest three periods of large discharge from outside and three periods of stable input(200-500 cm,800-980 cm and 1050-1200 cm).The sedimentation rates in the stable period are 0.102 cm·a^(-1),0.085 cm·a^(-1) and 0.139 cm·a^(-1),respectively.The periods of large discharge likely correspond to the intervals of the three rapid environmental changes,indicating that there were three rapid and high discharge periods related to melt water and/or heavy rainfall during the past 10000 years in this region.The analytical results also show that the physical properties are valuable in reconstructing past hydro-geomorphological fluctuations in the lake-catchment system.展开更多
基金Supported by the National Basic Research Program of China （2007CB815002）, and the National Natural Science Foundation of China （10775003, 10905002 and 10827505）.
基金Grants-in-Aid for Scientific Research from Ministry of Education,Science and Culture(Japan)to K.Kashiwaya[(A2)20253002]
文摘A 13-m long sediment core from Borsog Bay of Lake Khuvsgul,northern Mongolia records hydro-environmental changes during the past 10000 years;three rapid environmental changes(ca.2700 a BP,ca.6000 a BP and ca.8000 a BP based on ^(14)C dates of organic carbon materials) are detected in depth profiles of sediment physical properties.Temporal changes in the physical properties of the core(grain size,grain density and water content) also suggest three periods of large discharge from outside and three periods of stable input(200-500 cm,800-980 cm and 1050-1200 cm).The sedimentation rates in the stable period are 0.102 cm·a^(-1),0.085 cm·a^(-1) and 0.139 cm·a^(-1),respectively.The periods of large discharge likely correspond to the intervals of the three rapid environmental changes,indicating that there were three rapid and high discharge periods related to melt water and/or heavy rainfall during the past 10000 years in this region.The analytical results also show that the physical properties are valuable in reconstructing past hydro-geomorphological fluctuations in the lake-catchment system.
