Evidence for natural fire and climate history since 37 ka BP in the northern part of the South China Sea

摘要

The history of natural fire since 37 kaBP and its relationship toclimate for the northern part of the South China Sea are revealedfrom the statistic study of charcoal particles and associ- atedpollen data from deep sea core 17940 (20°07'N, 117°23'E, 1 727 m inwater depth). Our study indicates that, during the last glaciation,the concentration of charcoal and the ratio of con- centrationbetween charcoal and terrestrial pollen are much higher that that ofthe Holocene. This can be explained as the relatively high strengthand frequency of natural fire during glaciation which is probable dueto the drier climate; during the Last Glacial Maximum (LGM), thesubstantial rising or the concentration of large and medium charcoalparticles probably suggests the local source area of the naturalfires, i.e. the exposed continental shelf; moreover, the correlationbe- tween charcoal concentration with different size and pollenpercentage may elucidate different transport dynamics.