The Arctic is undergoing rapid changes due to climate warming and permafrost thaw, with implications for the release of previously preserved C. However, little is known about variation in SOC decomposability across High Arctic landscapes. We employed 90-day laboratory incubations, diffuse reflectance infra-red Fourier transform (DRIFT) and Near Edge X-ray Absorption Fine Structure (NEXAFS) spectroscopy to explore spatial variability in SOC decomposability in Mesic Tundra (MT), Wet Sedge (WS), and Polar Desert at the Cape Bounty Arctic Watershed Observatory (CBAWO), Nunavut. Vegetation type significantly influenced labile pool (M1), recalcitrant pools (M2) and labile mineralisation rate (k1). The k1 values were higher in WS than PD (p=0.019) and higher, although not significantly than MT. Conversely, PD had significantly higher M2 (p=0.007) than MT. DRIFT spectra revealed presence of labile SOC peaks (aliphatic-C bands 2853 and 2920cm-1) at all depths in WS as well as a significantly lower degree of decomposition index -DDI (recalcitrance index from DRIFT) than PD (H=12.97, p=0.01). NEXAFS analyses revealed that WS had a greater percentage of O-alkyl and carboxyl C, whereas MT and PD exhibited higher alkyl/O-alkyl ratios and significantly higher DDI values compared to WS. This indicates a higher degree of SOC recalcitrance in MT and PD. Strong positive correlation (ρ=0.725, p<0.01, R2=0.53) between alkyl/O-alkyl ratio (recalcitrance index from NEXAFS spectra) and SOC suggesting increasing recalcitrance with increasing SOC content. Our results suggest that spatial variability in SOC quality linked to vegetation type could influence rates of C release, with warming in the high Arctic.