Lake Qinghai Surface Sediment Isotope and Geochemical Data Xu, H.; Ai, L.; Tan, L.; An, Z. Xu, H. Ai, L. Tan, L. An, Z. earth science/paleoclimate/paleolimnology (delta 13C,organic matter,null,per mil,null,paleolimnology,null,null,N,null) earth science/paleoclimate/paleolimnology (carbon/nitrogen,sediment,null,dimensionless,null,paleolimnology,null,null,N,null) earth science/paleoclimate/paleolimnology (delta 18O,carbonate,null,per mil PDB,null,paleolimnology,null,null,N,null) earth science/paleoclimate/paleolimnology (depth,null,null,centimeter,null,paleolimnology,null,null,N,null) earth science/paleoclimate/paleolimnology (organic carbon,sediment,null,percent,null,paleolimnology,null,null,N,null) earth science/paleoclimate/paleolimnology (delta 13C,carbonate,null,per mil PDB,null,paleolimnology,null,null,N,null) earth science/paleoclimate/paleolimnology (carbonate,sediment,null,percent,null,paleolimnology,null,null,N,null) earth science/paleoclimate/paleolimnology (age,null,null,year Common Era,null,paleolimnology,null,null,N,null) earth science/paleoclimate/paleolimnology (Lake Qinghai>LATITUDE 37.058>LONGITUDE 100.303) Multi-proxy indices on annual/decadal scales during the past 600 years were developed from the surface sediments of Lake Qinghai based on 210Pb and 137Cs geochronology. The d13Ccarb, d18Ocarb, and total carbonate content are consistent with one another in trends and their variations have been mainly ascribed to regional temperature. It is suggested that the strong evaporation contributes in modifying d18O of lake water and d13C of the dissolved inorganic carbon of the surface water, and appears to be responsible for the covariance between d13Ccarb and d18Ocarb. Photosynthesis of the aquatic plants appears to have played a significant role in determining d15N of organic matter. The discrimination of 14N and 15N during photosynthesis may have triggered a positive linkage between temperatures and d15Norg (after removal of the stratigraphic trend).Variations of total organic carbon (TOC), C/N ratio, and d13Corg have been ascribed to local precipitation. TOC (after removal of the stratigraphic trend) is positively correlated with the C/N ratio (r = 0.45, a < 0.01), and negatively correlated with d13C of organic matter (d13Corg) (r = - 0.55, a < 0.01); while d13Corg is negatively correlated with the C/N ratio (r = - 0.48, a < 0.01). The climatic significance of these multi-proxy indices has been verified by comparing with the meteorological records and the climates inferred from tree rings in adjacent regions. STUDY NOTES: Stable isotope and geochemical data from near-surface sediments (upper 30 cm., ~600 yrBP) from Lake Qinghai, central China. The indices from surface sediments of Lake Qinghai can be generally divided into two groups. One is dominated by precipitation (TOC, C/N, d13Corg); the other is dominated by temperature (d13Ccarb, d18Ocarb, total carbonate content). NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Xu, H. Investigator : Ai, L. Investigator : Tan, L. Investigator : An, Z. 2008-11-01 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/6205 https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/asia/china/qinghai2006.xls https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/asia/china/qinghai2006.txt https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/asia/china/qinghai2006.xls https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/asia/china/qinghai2006.txt English https://www.ncdc.noaa.gov/paleo/study/6205 https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/asia/china/qinghai2006.xls https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/asia/china/qinghai2006.txt Xu, H.,Ai, L.,Tan, L.,An, Z. 2006. Stable isotopes in bulk carbonates and organic matter in recent sediments of Lake Qinghai and their climatic implications. Chemical Geology, 235(3–4), 262–275. START YEAR: 566 cal yr BP * END YEAR: -49 cal yr BP 100.303 37.058 100.303 37.058