Variations in Soil Organic Carbon Accumulation Between <i>Pinus kesiya</i> and <i>Pinus oocarpa</i> at Viphya Plantations in Malawi

This study pioneers the assessment of soil organic carbon (SOC) accumulation in Pinus kesiya and Pinus oocarpa at Viphya Plantations, addressing a critical gap in carbon sequestration research in Malawi. Unlike the well‐studied Miombo woodlands, Pine plantations, despite their prominence, have received limited attention. The findings offer novel insights with significant implications for Malawi’s contribution to global net‐zero targets and REDD + commitments. Therefore, this study estimated SOC accumulation variations and annual soil carbon sequestration between P. kesiya and P. oocarpa at the age of 16 years at Viphya plantations, Malawi. A total of 40 composite samples of soil were collected and analyzed for SOC using the Walkley–Black method. The results revealed that P. kesiya accumulates higher SOC (32.37 ± 2.75 tC/ha) compared with P. oocarpa (28.85 ± 1.22 tC/ha). Furthermore, P. kesiya had a higher annual soil carbon sequestration (7.41 ± 1.12 tCO 2 e/ha/yr) as compared to the annual soil carbon sequestration of P. oocarpa plantation (6.62 ± 0.46 tCO 2 e/ha/yr). Although the results are not statistically significant, this trend suggests a potential difference that may be biologically or environmentally relevant. Further research with longer observation periods may help clarify these differences and their implications. Therefore, this study’s findings underscore species‐specific characteristics as key determinants in carbon accumulation and annual soil carbon sequestration in Pinus tree species. The findings further show that the uncertainties were low (&lt; 2.0%) and fit within the IPCC’s recommended range (&lt; 15.0%). This suggests potential for carbon trading in Malawi using P. kesiya or P. oocarpa plantations.