Relationship between precipitation and the infiltration depth over the middle and lower reaches of the Yellow River and Yangtze-Huaihe River Valley

National Natural Science Foundation of China [40701021, 40625002, 40331013]; National Knowledge Innovation Program of Chinese Academy of Sciences [KZCX2-YW-315-2]

Elemental carbon record of paleofire history on the Chinese Loess Plateau during the last 420 ka and its response to environmental and climate changes

An elemental carbon (EC) record, covering the last 420 ka, was reconstructed using chemical oxidation method on a loess and paleosol sequence from the Lingtai section on the Chinese Loess Plateau. The EC record reveals the paleofire history and its relationship with climate and vegetation changes on the Chinese Loess Plateau. Our results show that the EC abundance is generally higher in the paleosols than in the loess layers, showing a glacial/interglacial pattern, which is coincident with biomass changes. This variation pattern indicates that paleofires were intensified when biomass accumulated and climate changed abruptly especially from wet to dry conditions. The EC abundance increases sharply at similar to 130 kaB.P., indicating a dramatic change in the vegetation and climate variation patterns. The occurrence of a peak value with the highest average EC abundance in the Holocene may reflect the occurrence of a major climate event at similar to 6 kaB.P., and may also be partly due to more frequent anthropogenic fire usages. (c) 2007 Elsevier B.V. All rights reserved.