Investigation of soil organic carbon pool in mixed beech-hornbeam (Case study: Shastkolteh forest)

The forest is one of the most important natural ecosystems with a high potential for carbon absorption and gradual emission and also its equilibrium and the absorption of atmospheric carbon dioxide and carbon storage. Temporal variation of carbon sequestration in Hyrcanian forests is an important issue, so the aim of this study was to investigate the monthly changes of soil organic carbon (SOC) storage and determine its potential in the mixed beech-hornbeam stand. For this purpose, 20 sample points were randomly selected in one hectare of mixed beech-hornbeam stands and soil monthly sampling was done in 20 cm depth over a year from February of 2014 to February of 2015. SOC, moisture content, bulk density and volume proportion of coarse fragments were determined. Litter falls were measured using litter traps, soil and atmosphere temperature as effective factors on SOC pool were recorded in each sample points. Results showed significant monthly changes of litter production, soil moisture and temperature, atmosphere temperature and SOC storage over a year in the level of 95 percent. Also, results showed the highest and the lowest levels of SOC storage were in February (93.06 t.ha-1) and August (63.62 t.ha-1), respectively.