The soil carbon pool in two spruce forests established on former open grazing land

Forest soils store a substantial amount of carbon and carbon is a key component in soil organic matter. During the stand development of a forest site, a proportion of the carbon sequestrated by trees and other vegetation is transferred into the soil by litterfall and roots, and thereby building up a soil carbon stock. The main goal of my study was to estimate the soil carbon pools in 55 and 15 years old Norway spruce (Picea abies) forest stands that are established on formerly open grazing land. The overall mean carbon content across all study sites was 2092 ± 993 g/m2 (± SD) with site-specific means ranging from 1043 ± 233 g/m2 to 3297 ± 828 g/m2. The soil carbon pool was largest in the 55 years old forest stand, whereas the 15 years old forest stand had the lowest amount of carbon across the study sites. The results showed different trends and variation in the amount of carbon content between and within the study sites. In particular there was a large variation in the size of the soil carbon pool across fine spatial scales