{"NOAAStudyId":"6205","contactInfo":{"address":"325 Broadway, E/NE31","city":"Boulder","constraints":"Please cite original publication, online resource, dataset and publication DOIs (where available), and date accessed when using downloaded data. If there is no publication information, please cite investigator, title, online resource, and date accessed. The appearance of external links associated with a dataset does not constitute endorsement by the Department of Commerce/National Oceanic and Atmospheric Administration of external Web sites or the information, products or services contained therein. For other than authorized activities, the Department of Commerce/NOAA does not exercise any editorial control over the information you may find at these locations. These links are provided consistent with the stated purpose of this Department of Commerce/NOAA Web site.","country":"USA","dataCenterUrl":"https://www.ncdc.noaa.gov/data-access/paleoclimatology-data","email":"paleo@noaa.gov","fax":"303-497-6513","longName":"National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce ","phone":"303-497-6280","postalCode":"80305-3328","shortName":"DOC/NOAA/NESDIS/NCEI","state":"CO","type":"CONTACT INFORMATION"},"contributionDate":"2008-11-01","dataPublisher":"NOAA","dataType":"PALEOLIMNOLOGY","dataTypeInformation":"https://www.ncdc.noaa.gov/data-access/paleoclimatology-data/datasets/lake","difMetadataLink":"http://www1.ncdc.noaa.gov/pub/data/metadata/published/paleo/dif/xml/noaa-lake-6205.xml","doi":null,"earliestYearBP":566,"earliestYearCE":1384,"entryId":"noaa-lake-6205","funding":[],"investigators":"Xu, H.; Ai, L.; Tan, L.; An, Z.","mostRecentYearBP":-49,"mostRecentYearCE":1999,"onlineResourceLink":"https://www.ncdc.noaa.gov/paleo/study/6205","originalSource":null,"publication":[{"abstract":"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.","author":null,"citation":"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.","edition":null,"identifier":null,"issue":null,"journal":"Chemical Geology","pages":null,"pubRank":"1","pubYear":2006,"reportNumber":null,"title":"Stable isotopes in bulk carbonates and organic matter in recent sediments of Lake Qinghai and their climatic implications","type":"publication","volume":null}],"reconstruction":"N","scienceKeywords":null,"site":[{"NOAASiteId":"20682","geo":{"geoType":"Feature","geometry":{"coordinates":["37.058","100.303"],"type":"POINT"},"properties":{"easternmostLongitude":"100.303","maxElevationMeters":"3192","minElevationMeters":"3192","northernmostLatitude":"37.058","southernmostLatitude":"37.058","westernmostLongitude":"100.303"}},"locationName":"Continent>Asia>Eastern Asia>China>Qinghai","mappable":"Y","paleoData":[{"NOAADataTableId":"9527","coreLengthMeters":null,"dataFile":[{"NOAAKeywords":["earth science>paleoclimate>paleolimnology>geochemistry"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/asia/china/qinghai2006.txt","linkText":"qinghai2006.txt","urlDescription":"Data","variables":[{"cvAdditionalInfo":null,"cvDataType":"PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"centimeter","cvWhat":"depth variable>depth"},{"cvAdditionalInfo":null,"cvDataType":"PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"year Common Era","cvWhat":"age variable>age"},{"cvAdditionalInfo":null,"cvDataType":"PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"biological material>bulk biological material>organic matter","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil","cvWhat":"chemical composition>isotope>isotope ratio>delta 13C"},{"cvAdditionalInfo":null,"cvDataType":"PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"geological material>bulk geological material>sediment","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"percent","cvWhat":"chemical composition>element or single-element molecule>carbon>organic carbon"},{"cvAdditionalInfo":null,"cvDataType":"PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"geological material>bulk geological material>sediment","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"dimensionless","cvWhat":"chemical composition>element or compound ratio>carbon/nitrogen"},{"cvAdditionalInfo":null,"cvDataType":"PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"geological material>identified mineral>carbonate","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil PDB","cvWhat":"chemical composition>isotope>isotope ratio>delta 13C"},{"cvAdditionalInfo":null,"cvDataType":"PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"geological material>identified mineral>carbonate","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil PDB","cvWhat":"chemical composition>isotope>isotope ratio>delta 18O"},{"cvAdditionalInfo":null,"cvDataType":"PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"geological material>bulk geological material>sediment","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"percent","cvWhat":"geological material>identified mineral>carbonate"}]},{"NOAAKeywords":["earth science>paleoclimate>paleolimnology>geochemistry"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/asia/china/qinghai2006.xls","linkText":"qinghai2006.xls","urlDescription":"Data","variables":[]}],"dataTableName":"Lake Qinghai LQINGHAI isotopes","dataTableNotes":null,"earliestYear":566,"earliestYearBP":566,"earliestYearCE":1384,"mostRecentYear":-49,"mostRecentYearBP":-49,"mostRecentYearCE":1999,"species":[],"timeUnit":"cal yr BP"}],"siteName":"Lake Qinghai"}],"studyCode":null,"studyName":"Lake Qinghai Surface Sediment Isotope and Geochemical Data","studyNotes":"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 \ntemperature (d13Ccarb, d18Ocarb, total carbonate content).","version":"1.0","xmlId":"2161"}