Abstract

This chapter analyzes the available information regarding the main drivers of global change operating in Patagonia, including climate change and its impact on biodiversity, the introduction of exotic species, change in land use and cover, and some emerging drivers of global change such as harmful algal blooms (HABs) and the increase in connectivity of human populations associated with the construction and expansion of the Austral Highway, and the bridge over the Chacao Channel in Chiloé. We emphasize the complexities associated with global change due to the synergies of the different global change drivers in Patagonia, such as the introduction of exotic species, climate, and the increased likelihood of fires, and between HABs, climate, and nutrient inputs. Global climate models for Patagonia project that by 2070, and assuming a scenario of moderate change in greenhouse gas concentrations (RCP 4.5), average temperature will increase from 0, 9 to 1.4 °C. Similarly, precipitation is projected to decrease between 5.5 and 116 mm on average; the highest precipitation reduction is 221 mm, with a modal reduction of 21 mm. In some areas, however, precipitation is projected to increase up to 77 mm. Although Patagonian ecosystems have been resilient and able to adapt to Holocene climate modifications, evidence suggests large and abrupt changes associated with European colonization in the twentieth century that go hand in hand with the increase in the incidence of fires, habitat loss and invasion of exotic species. In particular, an increase in exotic species plantations—together with a drier and warmer climate and the abundance of exotic herbivores that affect the regeneration of native species—can have far-reaching consequences for Patagonian ecosystems. This chapter concludes with a series of recommendations that address both the knowledge gaps identified and the impacts of global change in the area. Some of these include the regulation of productive activities (tourism and aquaculture), periodic diagnostics of the state of Patagonian ecosystems and the services they provide, and improved knowledge of ecosystem functioning, particularly climate change and the synergic action of different global change drivers on their resilience.