Vertical distribution of isotopes and nutrients of Castanopsis carlesii at different forest ages promoted by natural regeneration forest

• 1、Fujian Normal University,College of Geographical Science,Fuzhou,350007

Abstract： To investigate the difference of soil carbon, nitrogen, phosphorus content and carbon stable isotope in different forest ages. We analyzed the soil carbon, nitrogen, phosphorus content and carbon stable isotope of different forest ages . The results showed that the δ13C value in the soil of different forest ages ranged from -28.50‰ to -26.51‰, and the soil δ13C value increased with the deepening of soil layer. There was a significant linear negative correlation between the δ13C value and the organic carbon content in different forest ages. The β value was 21 years <49 years .Soil carbon contents of the 21-year and 49-year were 13.83 and 14.37 g.kg-1 respectively , the nitrogen contents were 0.92 and 1.03 g.kg-1, and the phosphorus contents were 0.27 and 0.33 g.kg-1 Soil SOC and decreased obviously with increasing soil depth. The β value of 49year indicating that the soil mineralization was weakened with the increase of forest age and the carbon sequestration of forest soil was strengthened.??

Keywords： Forest age Stable isotope Carbon nitrogen and phosphorus