Anthropogenic global defaunation and its consequences for planetary health

Abstract

The Convention on Biological Diversity has set the 20 Aichi targets for biodiversity by 2020. However, almost all indicators of the Aichi targets show negative trends. Anthropogenic pressure (human appropriation of biological productivity), biodiversity (Living Planet Index), biodiversity benefits (domesticated breeds, Red List of pollinators) show decline with negative consequences on resources and ecosystem services. Many academic studies and reports conducted by international organizations stressed that biodiversity loss is affecting ecosystem resilience but also health and well-being. However, we still lack a framework that could link socio-economics, ecosystems, biodiversity and health. The social-ecology approach links ecological and biological metabolism with social metabolism, where social systems are seen as hybrid systems between cultures, socio-economics (exchanges and flows) and environments (metabolic exchanges). Human societies can then be characterized by stocks and flows that involve: population and its demography, biophysical stocks and trade/production, land and its biological productivity. An important parameter is HANPP (Human Appropriation of the Net Primary Productivity). HANPP has doubled in the 20th century and scenarios suggest that this appropriation will continue to increase considerably in the coming decades. HANPP is an appropriate indicator for research into the impact of human intervention on biodiversity and can link human appropriation of environmental metabolism with ecological theories on biodiversity, like the species-energy hypothesis. We used the conceptual framework of social-ecology that links “drivers” (food consumption, energy), “pressures” (land use, HANPP), “states” (biodiversity change), “impacts” (reduction of the quality of ecosystem services) and “responses” (governance, land planning, conservation). This conceptual framework makes it possible to address the link between biodiversity and health. We tested this social-ecology framework using several databases at the nation level. We confirmed the species-energy hypothesis by showing a positive correlation between HANPP and declining biodiversity. The hypothesis of a reduction in ecosystem services for the regulation of infectious diseases appears also to be confirmed with an increase in zoonotic disease epidemics with the increase in HANPP at the world nation level. The incorporation of health components in social-ecology might provide governance tools for global biodiversity conservation and planetary health.