COMPARING TOTAL AND ACTIVE SOIL ORGANIC CARBON FRACTIONS UNDER DIFFERENT FOREST MANAGEMENT REGIMES**

Authors

Daniella C. Odhiambo*, GMC Prep, Milledgeville, GA 31061Follow
Alanis Bernis*, Georgia College & State University, Milledgeville, GA 31061Follow
Rebecca Barringer*, Georgia College & State University, Milledgeville, GA 31061Follow
Victoria Alden*, Georgia College & State University, Milledgeville, GA 31061Follow
Leah Bartleston*, Georgia College & State University, Milledgeville, GA 31061Follow
Christine Mutiti, Georgia College & State University, Milledgeville, GA 31061Follow

Abstract

Soil organic carbon (SOC) plays a critical role in forest ecosystem functioning and carbon sequestration. Active carbon represents the labile, biologically available fraction of SOC and is important for nutrient cycling and soil health. Forest type and stand age can influence both the quantity and quality of soil carbon, yet comparative data across different forest systems remain limited. We evaluated SOC and active carbon across three forest sites within the Bartram Wildlife Management Area in Milledgeville, GA: an unmanaged hardwood stand, a relatively younger pine stand, and an older pine stand, each approximately 20 acres. Twenty soil samples were collected from each site at a depth of 30 cm. SOC was determined using the loss-on-ignition method, and active carbon was measured using the permanganate oxidizable carbon (POXC) method. One-way ANOVA was used to compare %SOC, active carbon concentration (mg/kg), and the proportion of SOC as active carbon among sites. The hardwood site exhibited significantly higher %SOC and active carbon than both pine sites (P < 0.001), which did not differ from each other. Additionally, the hardwood and younger pine sites had a significantly greater proportion of SOC as active carbon compared to the older pine site (P < 0.001). These results indicate that forest type and stand age influence both SOC quantity and its active fraction. Hardwood systems maintain higher SOC and active carbon, suggesting greater potential for nutrient cycling and soil fertility. In contrast, older pine stands store carbon in more stable forms, indicating a shift toward long-term sequestration rather than active cycling. These findings have implications for carbon management strategies in forest ecosystems, highlighting the importance of considering both absolute and relative measures of soil carbon when evaluating ecosystem carbon dynamics and management impacts.

Recommended Citation

Odhiambo*, Daniella C.; Bernis*, Alanis; Barringer*, Rebecca; Alden*, Victoria; Bartleston*, Leah; and Mutiti, Christine (2026) "COMPARING TOTAL AND ACTIVE SOIL ORGANIC CARBON FRACTIONS UNDER DIFFERENT FOREST MANAGEMENT REGIMES**," Georgia Journal of Science, Vol. 84, No. 1, Article 193.
Available at: https://digitalcommons.gaacademy.org/gjs/vol84/iss1/193