ABSTRACT Carbon dioxide is one of the most important greenhouse gases responsible for global climate change. Terrestrial ecosystems are widely recognized as useful mechanisms, as they store large quantities of carbon in their bodies. In this context, the present study aims at analyzing carbon stocks in forest (both productive and degraded), grassland, and agricultural ecosystems of Kizildag Planning Unit. To this end, forest inventory data, published statistics, and GIS tools were used for modeling carbon densities of these three ecosystems in a spatially explicit manner. Moreover, carbon contents were estimated for different pools including above- and below-ground biomass, litter layer, deadwood, and soil components. Results showed that a total of nearly 3.5 million tons of carbon stored in the entire study area. When standardized to per unit area, productive and degraded forests stocked the most significant amounts followed by grassland and cropland land use/land cover (LULC) classes. The average density was 120.8 tons ha-1 for productive forests, while it was 32.3 tons ha-1 for croplands. The vast majority of these amounts stocked in soil pools for each LULC classes. Therefore, special attention should be paid for soil carbon studies which are very rare in the region. Regarding spatial distribution, Kizildag showed a rather non-homogeneous pattern in terms of carbon densities. Hotspots generally accumulated in the southwestern parts, as well as near the east border of the study area. Carbon densities could be as high as 200-245 tons ha-1 in these hotspots. Those areas were dominated by mixed stands of Taurus fir, cedar, and black pine at older ages and they were designated primarily for protective functions in the forest management plan. It is concluded that vast degraded forestlands in the region offer great opportunities to forest managers as an effective mechanism in combatting climate change. Therefore, rehabilitation, afforestation, and forest protection activities should be accelerated as possible.