Combining with the diatom-based conductivity transfer function from Qing-hai-Xizang (Tibetan) Plateau lakes, the lake salinity for the past 300 years was quantitatively reconstructed based on the analysis of diatom as...Combining with the diatom-based conductivity transfer function from Qing-hai-Xizang (Tibetan) Plateau lakes, the lake salinity for the past 300 years was quantitatively reconstructed based on the analysis of diatom assemblages from a sediment core in Chencuo Lake, southern Tibet. The distinct negative relationship between inferred conductivity and recorded lakelevels in recent years suggests that the lake salinity can reflect the fluctuations of effective moisture of climate in lake area. The salinity inferred from diatoms reveals several major hydrological episodes. An obvious desalination of lake water occurred during the last cold interval of the Little Ice Age (about 1845–1885 AD), indicating a cold and moist climate. The lake salinity presented a rapid increase trend since the middle 1960s, with a peak value and high amplitude of salinity variability in the whole past 300 years. The low effective moisture inferred from the lake salinity may have contributed to the enhanced evaporation by the continuous increase of temperature in recent years. Keywords diatoms - conductivity or salinity - quantitative reconstruction - Chencuo Lake展开更多
Based on careful sampling and accurate analysis of recent sediments in Lake Chenghai, this paper discusses the staggered positive/negative correlation between organic carbon (OC) concentration and inorganic carbon (IC...Based on careful sampling and accurate analysis of recent sediments in Lake Chenghai, this paper discusses the staggered positive/negative correlation between organic carbon (OC) concentration and inorganic carbon (IC) concentration. The result indicates that temperature change, and its induced relative changes are the main factors affecting the relationship between IC concentration, δ13C of carbonate and OC concentration. When temperature and its induced photosynthesis strength change control autochthonous calcite precipitation, OC concentration is positively correlated with IC concentration and δ13C of carbonate. When temperature and its induced physical/chemical changes dominate, OC concentration displays negative correlation with IC concentration and δ13C of carbonate. IC concentration and δ13C of carbonate in sediments of Lake Chenghai are good proxies for climatic warm/cold changes.展开更多
文摘Combining with the diatom-based conductivity transfer function from Qing-hai-Xizang (Tibetan) Plateau lakes, the lake salinity for the past 300 years was quantitatively reconstructed based on the analysis of diatom assemblages from a sediment core in Chencuo Lake, southern Tibet. The distinct negative relationship between inferred conductivity and recorded lakelevels in recent years suggests that the lake salinity can reflect the fluctuations of effective moisture of climate in lake area. The salinity inferred from diatoms reveals several major hydrological episodes. An obvious desalination of lake water occurred during the last cold interval of the Little Ice Age (about 1845–1885 AD), indicating a cold and moist climate. The lake salinity presented a rapid increase trend since the middle 1960s, with a peak value and high amplitude of salinity variability in the whole past 300 years. The low effective moisture inferred from the lake salinity may have contributed to the enhanced evaporation by the continuous increase of temperature in recent years. Keywords diatoms - conductivity or salinity - quantitative reconstruction - Chencuo Lake
基金This work was supported by the Knowledge Innovation Project of Chinese Academy of Sciences (KZCX2-105) the Innovation Realm Project of the State Key Laboratory of Environmental Geochemistry and the National Natural Science Foundation of China (Gran
文摘Based on careful sampling and accurate analysis of recent sediments in Lake Chenghai, this paper discusses the staggered positive/negative correlation between organic carbon (OC) concentration and inorganic carbon (IC) concentration. The result indicates that temperature change, and its induced relative changes are the main factors affecting the relationship between IC concentration, δ13C of carbonate and OC concentration. When temperature and its induced photosynthesis strength change control autochthonous calcite precipitation, OC concentration is positively correlated with IC concentration and δ13C of carbonate. When temperature and its induced physical/chemical changes dominate, OC concentration displays negative correlation with IC concentration and δ13C of carbonate. IC concentration and δ13C of carbonate in sediments of Lake Chenghai are good proxies for climatic warm/cold changes.
