Carbon and nitrogen storage in California sage scrub and non-native grassland habitats

• We measured C and N storage in California sage scrub and non-native grassland.
• We modeled shrub branch biomass with empirically-derived models.
• C and N storage was higher in California sage scrub than in non-native grassland.
• C and N storage was not different between intact and recovering California sage scrub.
• Preservation and restoration of California sage scrub has C and N storage benefits.

Human activity has altered global carbon and nitrogen cycles, leading to changes in global temperatures and plant communities. Because atmospheric carbon (C) and nitrogen (N) concentrations are affected by storage in terrestrial vegetation and soil, it is critical to understand how conversions from native to non-native vegetation may alter the C and N storage potential of terrestrial landscapes. In this study, we compared C and N storage in native California sage scrub, non-native grassland, and recovering California sage scrub habitats in the spring and fall by determining the C and N content in aboveground biomass, litter, and surface soil. Significantly more C and N were stored in intact and recovering California sage scrub than in grassland habitats. Intact and recovering sage scrub did not differ significantly in C or N storage. Our results highlight that preserving and restoring California sage scrub habitat not only provides habitat for native biodiversity, but also increases carbon and nitrogen storage potential even without restoration to intact sage scrub.