Preliminary quantification of the carbon stock of lowland and midland scrublands of Tenerife, Canary Islands

Abstract

The consideration of terrestrial ecosystems as carbon sinks is usually linked to forests and arboreal species. However, insular mature ecosystems dominated by native shrub species could be acting as sinks and contributing to the carbon stock on islands. In the Canary Islands, scrublands occupy around 25% of the archipelago land area. Here we present preliminary data about the total amount of carbon stored in the aboveground vegetation of mature coastal scrubland, and the lowland and midland secondary scrubs of the island of Tenerife. Five plant communities were characterized by measuring, in 40 plots of 400 m2, the plant cover and the amount of aboveground biomass per unit area, to calculate the carbon stored in each community. We measured all the individuals of scrub and tree species in the plot, including height, two diameters, and basal steam diameters when possible. For the most frequent and abundant scrub species of Tenerife (native, endemic, and invasive), we built preliminary allometric equations using their volumetric data to estimate the biomass of individuals. The average carbon stored in each community was calculated and extrapolated to the total area occupied in Tenerife. Although the carbon accumulated in scrubs is lower than in forests, the importance of their contribution lies in their wide distribution. Information provided by this work is intended to guide management measures to maximize the compensation of the carbon footprint of the Canaries. Additionally, allometric equations will provide a non-destructive method to calculate biomass content in shrubs in the future. The need for protection and conservation of the Canarian ecosystems with the aim of preserving the natural heritage is more than accepted. However, the ecosystem service of carbon sequestration done by native species, not only trees but also shrubs, could be another reason for the conservation and restoration of natural and degraded areas