Determination of soil organic carbon dynamics in land use changes

Soil is the largest carbon (C) reserve of the terrestrial biosphere. The soil carbon is three times that of atmospheric carbon, so even the slightest change in soil carbon affects atmospheric carbon. The carbon dioxide (CO₂) flow between the soil and the atmosphere is a process which is strongly dependent on the 'water extractable organic carbon (WEOC)' fraction which directly affects the CO2 outflow in the soil with a high biodegradability rate and land use changes. The level of carbon dioxide (CO2) in the atmosphere is increasing due to the increase in fossil fuel consumption, destruction of forests, conventional agricultural practices, land use changing, turning pastures into agriculture and industrial developments. One of the cheapest and best way to prevent CO2 growth is to store carbon in the soil. The aim of this study is to determine how soil organic carbon (SOC) dynamics in Eskişehir province changes with different land uses (pasture, agriculture, forest) and depth, and how it correlates with other soil parameters; in addition, in order to examine WEOC fraction in detail, both 'cold and hot' and 'only hot' extractions are used to determine the optimum extraction method in different land uses. As a result of the analyzes and statistical evaluations, positive correlations were found between SOC, WEOC and hot WEOC (HWEOC) values (R= 0.834; R= 0.785, p< 0.01, respectively). SOC, WEOC and HWEOC decreased with increasing depth in pasture and forest lands; did not change significantly in the agricultural land. HWEOC analysis is insufficient in the pasture land; but much more successful in agriculture and forest lands than WEOC analysis.