Assessment of Soil Carbon Stock in Different Land Use Types of Eastern Türkiye

Soil organic carbon (SOC) is one of the sensitive indicators in monitoring changes in terrestrial ecosystems and land use practices. Studies to determine SOC stocks and increase their capacity are of critical importance in combating climate change and preventing land degradation. This study evaluated SOC stocks in a semi-arid micro-watershed with different land uses in the Eastern Anatolia Region. The land use types examined were identified as moderate rangeland (MR), weak rangeland (WR), agricultural land (AL), and degraded area (DA). Representative areas (1 ha each) were selected based on dominant vegetation and management history. A total of 60 soil samples were collected using a random sampling method, with 15 samples per hectare evenly distributed to minimize spatial variability. Sampling was conducted at two depths: 0-10 cm and 10-20 cm. Bulk density (BD), electrical conductivity (EC), pH, soil texture, calcium carbonate (CaCO3), and SOC analyses were conducted on the soil samples. The research findings revealed statistically significant differences in SOC stocks between land uses (P<0.001). The SOC amounts were calculated as follows: MR (50.79 Mg C ha-1) > AL (42.36 Mg C ha-1) > WR (30.86 Mg C ha-1) > DA (11.69 Mg C ha-1). These findings indicate that land use and management practices significantly influence SOC stocks. The highest SOC stocks (50.79 Mg C ha-¹) were recorded in MR and conservation of these areas can contribute significantly to carbon sequestration. The lowest SOC stocks (11.69 Mg C ha-¹) were recorded in DA and erosion control and vegetation restoration were recommended. For intermediate SOC stocks (42.36 Mg C ha-¹) in AL, the use of organic fertilizers and reduced tillage practices can reduce SOC losses. Lower SOC stocks (30.86 Mg C ha-¹) were recorded in WR, and improved grazing management was recommended. Additionally, it can be stated that sustainable soil management practices could prevent land degradation and thus contribute significantly to combating climate change.