This study investigated the dynamics of carbon stock and Normalized Difference Vegetation Index (NDVI) as indicators of oil palm (Elaeis guineensis Jacq.) productivity in peat ecosystems under varying applications of compound NPK fertilizer. Research was conducted in Benteng Hulu Village, Mempura District, Siak Regency, Riau Province, Indonesia, from March 2023 to April 2024 using mature oil palm plants (10-12 years old) grown on different peat depths. A nested plot design was employed with three peat depth categories (shallow: 1-2 m, moderate: 2-3 m, and deep: >3 m) as main plots and five Compound NPK fertilizer treatments (T0: control, T1: 75%, T2: 100%, T3: 125%, and T4: 150% of recommended dose) as subplots. Results demonstrated significant stratification in carbon stocks across peat depths, with deep peat consistently maintaining higher carbon storage (564-597 Mg C ha⁻¹) compared to moderate (485-523 Mg C ha⁻¹) and shallow peat (421-452 Mg C ha⁻¹). UAV-derived NDVI values and Fresh Fruit Bunch (FFB) yields showed optimum responses at T3 treatment (125% of recommended dose), with shallow peat consistently outperforming deeper categories. Strong positive correlations were observed between NDVI and FFB yield (r = 0.83-0.87) across all peat depths, while water table depth exhibited strong negative correlations with carbon stock (r = -0.72 to -0.83). These findings indicate that moderate fertilization intensity (100-125% of recommended rates) optimizes the balance between carbon storage, vegetation health, and agricultural productivity in tropical peatland oil palm systems, supporting sustainable intensification approaches that simultaneously address climate mitigation and food security goals.