An unprecedented and continuing loss of biodiversity has been sparked by anthropogenic climate change together with the intensive use and destruction of natural ecosystems. However, since the public often views the climate crisis and the biodiversity crisis as two separate catastrophes, an international team of researchers including paleontologist Prof. Dr. Wolfgang Kiessling from Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) calls for adopting a new perspective: In their review study just released in the journal “Science”, they recommend protecting and restoring at least 30 percent of all land, freshwater and marine zones, establishing a network of interconnected protected areas, and promoting interdisciplinary collaboration between institutions.

Human beings have massively changed the Earth’s climate system by producing greenhouse gas emissions that caused the global mean temperature to rise by more than 1.1 degrees Celsius compared to the preindustrial era. The consequences for our planet are manifold and include among others the rising of global sea levels, frequent extreme weather events, and a loss in biodiversity.

Climate and biodiversity go hand in hand

In their newly published report, “Overcoming the coupled climate and biodiversity crises and their societal impacts”, 18 international researchers highlight the connection between climate crisis and biodiversity loss. Prof. Dr. Wolfgang Kiessling, FAU paleontologist and Chair of Palaeoenvironmental Research at Geozentrum Nordbayern, is one of the co-authors. He explains: “The drastic change in temperatures we experience right now has a great impact on the habitats of animate beings. Since they all have their specific range of tolerance, organisms are forced to shift their territory due to climate change. This comes with different challenges. For instance, mobile species can only migrate to cooler environments for so long until they hit a dead end, for example the coast of a landmass. Sessile organisms like coral reefs on the other hand take several generations to change their habitat. If you look at it long-term, for many of them it may already be too late.”

What makes matters worse is the loss of ecosystems due to agriculture, fishing and industry. The study’s authors estimate that human activities have altered roughly 75 percent of the land surface and 66 percent of the marine waters on our planet. As a result, today approximately 80 percent of the biomass from mammals and 50 percent of plant biomass have been lost, while more species are in danger of extinction than at any time in human history.

Coming full circle, global warming and the destruction of natural habitats not only lead to biodiversity loss, but also reduce the capacity of organisms, soils and sediments to store carbon, which in turn exacerbates the climate crisis.

Adapting now for a good future

In order to address these multiple crises, the researchers propose a combination of emissions reduction, restoration and protection measures, intelligent land-use management, and promoting cross-institutional competencies among political actors. “The key to a good future must be to not only focus on reducing emissions but to make sustainable adaptions to the already existing change in our climate, especially through nature-based solutions”, says Kiessling.

This includes the protection of coastlines by maintaining coral reefs and wetlands; the restoration of at least 30 percent of land, freshwater and marine zones to prevent further biodiversity losses; and the connection of protected areas via migration corridors, hence creating a web of safe habitats around the world for animals. The paper further emphasizes that agriculture and fishing must focus on sustainability: Resource-conserving forms of use and a reliable food supply for the human race have to be ensured, with concepts leading to intensified carbon dioxide uptake and carbon fixation in biomass and soils being prioritized. In addition, sufficient havens must be created for species responsible for making harvests possible, e.g. the insects that pollinate fruit trees.

Unanimous approach necessary

For all of these measures to be successful, countries and institutions across the world need to stand on common ground. As Kiessling puts it: “No matter the issue, be it economic, political or social, we all must look at it with climate change, biodiversity and sustainability in mind, and most importantly: We must understand that what impacts one country will definitely have an effect on others. This is why we need joint strategies and regular exchange between institutions and world leaders.”

The full report is available via the DOI: 10.1126/science.abl4881