Analysis of carbon isotope in phytoliths from C3 and C4 plants and modern soils

The analysis of carbon isotope in phytoliths from modern plants and surface soils in China shows that the values of carbon isotope are consistent with those from C3 and C4 plants, and the processes of photosynthesis of the or iginal plants can be clearly identified by carbon isotope in phytoliths. Th e value of carbon isotope varied from -23.8 parts per thousand to -28 parts per thousand, with the maximum distributed in the latitude zone from 34 de greesN to 40 degreesN in North China and East China areas, and the minimum in the Northeast China and South China regions. The values of carbon of phy toliths tend to increase from low to high and then reduce to low value agai n as the latitude increases. In the same latitude zone, the carbon isotope in phytoliths from grassland soil under the trees is obviously lower than t hat from grassland soil without any trees with the difference of 1 parts pe r thousand - 2 parts per thousand.