
Up to one million out of the roughly 8 million estimated species are threatened with extinction due to the impact of human activities, affirms the new report from the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES).
Compiled by 145 authors and with inputs from another 310 professionals, the IPBES Global Assessment Report on Biodiversity and Ecosystem Services is the most comprehensive assessment of changes in biodiversity over the past decades. More than 15,000 scientific and government sources were reviewed, including indigenous and local knowledge. The final report was approved by representatives of 132 governments in Paris at the beginning of this month.
Causes behind this situation
The drivers with the largest global impacts behind these changes in nature were analysed and ranked. In descending order, they are: (1) changes in land and sea use; (2) direct exploitation of organisms; (3) climate change; (4) pollution and (5) the spread of invasive species.
About 75% of the terrestrial and 66% of the marine environment have been severely altered by human actions. These alterations are mainly derived from the production of food, with more than 33% of the land surface and 75% of the freshwater resources dedicated to crop and livestock production. Agricultural activities also are one of the principal greenhouse gas producers, accounting for roughly 25% of total emissions. Aside from agricultural expansion, another of the main causes behind land use change is the increase of surface occupied by urban areas, which has doubled since 1992. As the global population continues to grow, agricultural and urban threats to the environment will increase.
As of 2015, 33% marine fish stocks were being harvested in an unsustainable manner, while 60% were maximally sustainably harvested and only 7% under that level.
This report also confirms the intimate link between climate change and biodiversity loss. Around 5% of all existing species would be threatened if we reach an increase of 2°C relative to pre-industrial levels. This seems likely to happen, unless greenhouse gas emissions are reduced drastically within the next years. Nevertheless, it is estimated that the distribution of 47% of terrestrial non-volant mammals and almost 25% of birds may have already been negatively affected by climate change.
Plastic pollution has increased 10 times since 1980. 300-400 million tons of heavy metals, solvents, toxic sludge and other industrial wastes are annually thrown into the world’s waters, while fertilizers entering coastal ecosystems have produced more than 400 marine ‘dead zones’ with a total surface of more than 245,000 km2.
The numbers of invasive alien species per country have increased by roughly 70% since 1970, across 21 countries with detailed records. Meanwhile, the average abundance of native species in most major terrestrial habitats has decreased by 20% relative to 1900.
“The overwhelming evidence of the IPBES Global Assessment, from a wide range of different fields of knowledge, presents an ominous picture,” said IPBES Chair, Sir Robert Watson. “The health of ecosystems on which we and all other species depend is deteriorating more rapidly than ever. We are eroding the very foundations of our economies, livelihoods, food security, health and quality of life worldwide.”
What can we do?
It’s not too late to revert this critical situation, the report says, but it will only happen if we start acting now. This “transformative change” will require the sustainable production of food and other resources, alongside with a reduction in greenhouse gas emissions. Society needs to shift from an economical growth perspective to a nature-based one. The report also confirms that nature managed by indigenous people and local communities are in better health than nature managed by other institutions. To protect nature better, governments need to learn from these communities, implementing their knowledge of nature into future policies.
From the Inspire4Nature partnership, we are concerned about the future of biodiversity and we are actively working from the Science-Policy interface to achieve a better future. Our projects encompass a wide variety of relevant issues such as invasive species monitoring, evaluating the efficacy of protected areas, identifying important areas for the persistence of biodiversity (KBAs and OECMs) and identifying species vulnerable to climate change, amongst others.