Carbon stocks and biodiversity conservation on a small island: Pico (the Azores, Portugal)

The loss of carbon storage and sequestration capacity has been increasingly assessed and analyzed worldwide as among the factors causing or amplifying climate change. Solutions that contribute to decreasing the release of carbon and increasing its sequestration, without compromising currently threatened ecosystems, are required, especially for small territories. This study focuses on the strategies to increase the resilience of small islands to these losses, including spatial management to prevent and adapt to climate change while preserving biodiversity. Changes in carbon storage on Pico Island (Azores, Portugal) between 1998 and 2013 were assessed using the InVEST (Integrated Valuation of Ecosystem Services and Tradeoffs) Carbon Storage and Sequestration model. Changes in carbon stocks caused by changes in land use during this period, and the stocks' relationships with protected areas and the quality of natural habitats on Pico Island, were analyzed. Bogs and Azorean endemic Macaronesian heaths store more carbon per ha. Alien species are invading natural areas, and their carbon values need to be carefully addressed. Results, however, indicated that simultaneously increasing carbon stocks (economical value) and protecting biodiversity (environmental value) is possible by adapted and discussed management actions. This study supports the strategies that promote the potential of the conservation of biodiversity for mitigating climate change. The proposed management guidelines can be applied to other Macaronesian islands and, with local adaptations, to other outermost regions.