Global environmental change in the Anthropocene: challenges for terrestrial biodiversity and sustainability

The biosphere is experiencing an unprecedented loss of all life forms as a result of anthropogenic climate and land-use change. Biodiversity conservation and climate change mitigation are now non-negotiable, strategic, and socially imperative investments. This thesis presents a series of studies combining extensive environmental and socio-economic datasets to address questions about the dynamic biophysical, geopolitical, and social contexts of implementing these imperatives. Interrogating datasets within these contexts allow quantification of pressures on biodiversity and can inform conservation policy and actions. First, using the projected velocity of future climate and land-use change, I map areas where species need to track climate conditions by shifting distributions rapidly and the degree of land-use instability they may encounter—a vast majority of which overlap areas of conservation importance (global protected areas and Earth’s remaining wilderness). Specifically, I show that the biodiversity contained within more than one-quarter (~27%) of the world’s protected areas (PAs)— ~7% of which are under restrictive management—may experience high rates of both climate and land-use change by 2050. PAs located in high conservation value regions of moist biomes and that are within less-restrictive management categories are most exposed. Moreover, locations within wilderness most vulnerable to high rates of both of these stressors are those of enormous uniqueness for biodiversity conservation that are least protected. Furthermore, ii more than half (53%) of the global wilderness areas may undergo climate shifts by 2050, undermining their capacity to shelter species from climate change impacts and successful biodiversity conservation outcomes. The magnitude of the effect of climate and land-use changes differed between the alternative scenarios and showed considerable biogeographic heterogeneity, requiring a mix of actions at local, national, and transnational scales. Notably, I find that using mixed actions as part of nations’ internationally determined contributions to climate change mitigation (including increasing protection, managing outside reserves areas, and restoration actions needed to enhance species adaptation) are constrained by environmental and socioeconomic factors such as development aid, food insecurity, and population growth. Worryingly, the positive role of development aid on mitigation attenuated for poorly-governed regions with food insecurity. Overall, I show that, in addition to global emission reduction efforts, more local land-use change actions are required to enhance biodiversity conservation. Findings can inform countries seeking to implement nationally determined contributions to carefully consider food security safeguards and adopt sustainable restoration and afforestation efforts. They also elucidate a need for stronger coordination among local-level and international bodies in developing effective tools for addressing biodiversity loss and climate change.