| Popis: |
We analyzed the characteristics of organic matter TOC,TN andδ13C value and sand sediment grain size from samples of Jianghan Plain and discussed its relationship with climatic circumstance. The results show that: the TOC and TN of the organic materials in sediments are higher, but theδ13C are lower and grain sizes are coarser during warmer and wetter climatic episodes, On the other hand, during colder and dryer climatic episodes, the TOC and TN contents in sediments are lower. Theδ13C are lower and grain sizes are finer. With the results we reconstructed the evolution sequence of paleoclimate in Jianghan Plain region since 9000 aBP. It has four stages as follows:8900 -6070 aBP,warm and wet; 6070 -4600 aBP,cold and dry;4600 -2500 aBP,warm and wet; 2500 -500 aBP,cool and dry. |
