| Resum: |
Human impacts on earth-system processes are overshooting several planetary boundaries, not only in terms of CO2 emissions and climate change, but also land-use change, biodiversity loss, chemical pollution, and biogeochemical flows. The current rate of biodiversity loss is particularly concerning; in a comprehensive review of extant evidence, the UN Intergovernmental Science Policy Platform on Biodiversity and Ecosystem Services found that, on our present trajectory, around one million species are now at risk of extinction, many within decades. This trend is indicative of widespread habitat fragmentation, ecosystem disruption, and ecological breakdown. These problems are being driven in large part by global resource use, through processes of material extraction, production, consumption, and waste. Resource use has a range of impacts on terrestrial and marine ecosystems, including on forests, soils, wetlands, lakes, rivers, and oceans, and resource use is understood to be a robust proxy for environmental pressure. Steinmann and colleagues showed that resource use accounts for more than 90% of the variation in environmental damage indicators. The UN International Resource Panel found that resource use is responsible for 90% of total global biodiversity loss and water stress. Moreover, as van der Voet and colleagues showed, although impacts vary by material and as technologies change, there is a link between aggregate mass flows and ecological impact, with a correlation coefficient of 0·73. Although differences between individual materials are important, aggregate material use is a key indicator for environmental policy. Global material use has increased markedly over the past half century, to the point where, as of 2017, the world economy is consuming over 90 billion tonnes of materials per year-well in excess of what industrial ecologists consider to be the sustainable limit. This increasing trend holds across all categories of materials, including biomass, metals, non-metallic minerals, and fossil fuels. However, not all nations are equally responsible for this trend; some nations use substantially more resources per capita than others. Although previous research has explored the question of national responsibility for CO2 emissions and climate change, such analysis has not been applied to other forms of environmental pressure. In this study, we quantify national responsibility for ecological damages related to excess material use, using a method rooted in the principle that the planet's resources and ecosystems are a commons, and that all people are entitled to an equal, sustainable share. This principle has been articulated in the climate literature, and the approach used here builds on a method that was developed for CO2 emissions. |
visitant ::
identificació
(Universitat Autònoma de Barcelona. Institut de Ciència i Tecnologia Ambientals)
