Dust transport from northeastern China inferred from carbon isotopes of atmospheric dust carbonate

We made carbon and oxygen isotope analyses on the carbonates in atmospheric dust samples (hereafter, atmospheric dust carbonates) over the saline land of Songnen Plain (SSL) and at Changchun, 50 km eastward from the east margin of SSL, as well as in the surface soil samples in SSL. The atmospheric dust carbonates from SSL and Changchun had similar carbon isotopic composition as the soil carbonates from SSL, while showing a distinct difference with the atmospheric dust carbonates in the northwestern Chinese deserts. The atmospheric dust carbonates for two of the three heavy dust storms at Changchun had a similar carbon isotopic composition as those in SSL. The dust emission from SSL makes a significant contribution to the dust storms in the downwind area. Carbon isotopic composition of the atmospheric dust carbonates should be a useful indicator for inferring the dust source. We have also noted a depleting trend of 13C of atmospheric dust carbonates from west to east over northern China. The incorporating process of dust generated in areas under the pathway of the Asian dust transport might be investigated from the carbon isotopic composition in atmospheric dust carbonates.