Abstract:

The contents of carbon and nitrogen and C∶N ratio stoichiometry in three warm temperate deciduous broadleaf forest types were investigated in Dongling Mountains, northern China. The results showed that: 1) The carbon concentrations of soil and tree layer decreased successively from Betula platyphylla(birch) forest (BF), Quercus liaotungensis (oak) and Betula dahurica mixed deciduous broadleaf forest (MF), to Quercus liaotungensis (oak) forest (OF). The tree layer in the mixed forests had the highest nitrogen concentration, which was more than twice that of the others. However, no significant difference was found in the carbon and nitrogen contents in soil microbial among the three forest types. 2) The variation of C∶N ratio in the soil microbial was smaller than that in the tree layer among the three forest types, regardless of the soil C and N concentrations. 3) The C∶N ratios of both the soil and the soil microbial were not significantly changed and appeared well-constrained in the three forest types.

Key words: C and N contents, C∶N ratio, warm temperate deciduous broadleaf forest, ecosystem, stoichiometry, Dongling Mountain