Diverging land-use projections cause large variability in their impacts on ecosystems
Team members Anita Bayer, Almut Arneth and Peter Anthoni published a study in Earth System Dynamics demonstrating the large variability in ecosystem service indicators caused by diverging future land-use scenarios.
Post-2020 biodiversity targets need to embrace climate change
A considerable number of existing and proposed post-2020 biodiversity targets by international organizations are at risk of being severely compromised due to climate change, even if other barriers such as habitat exploitation are removed argue the authors of a study led by Almut Arneth. According to their analysis published in PNAS, global warming accelerates the loss of biodiversity. Vice versa, measures to protect biodiversity may also mitigate the impacts of climate change. The authors suggest that flexible approaches to conservation would allow dynamic responses to the effects of climate change on habitats and species.
Published: A comprehensive quantification of global nitrous oxide sources and sinks
Nitrous oxide (N₂O), like carbon dioxide, is a long-lived greenhouse gas that accumulates in the atmosphere. Over the past 150 years, increasing atmospheric N₂O concentrations have contributed to stratospheric ozone depletion and climate change, with the current rate of increase estimated at 2 per cent per decade.
Forest disturbance play important role for land carbon sinks and climate.
We contributed to an international study, led by our former team member Tom Pugh, published in Nature Climate Change which demonstrates the large importance of accounting for frequency and extend of disturbance for carbon cycling in forest ecosystems. The work highlights how even small changes in disturbance interval, for instance through climate change or human forest management, would impact today’s forest carbon sink.
The world’s biggest terrestrial carbon sinks are found in young forests.
More than half of the carbon sink in the world’s forests is in areas where the trees are relatively young – under 140 years old – rather than in tropical rainforests, an international team of researchers including Almut Arneth shows. These trees have typically ‘regrown’ on land previously used for agriculture, or cleared by fire or harvest and it is their young age that is one of the main drivers of this carbon uptake. Previously it had been thought that the carbon uptake by forests was overwhelmingly due to fertilisation of tree growth by increasing levels of carbon dioxide in the atmosphere. However, the analysis published in PNAS (www.pnas.org/cgi/doi/10.1073/pnas.1810512116) demonstrates that areas where forests are re-growing take up large amounts of carbon not only due to these fertilisation effects, but also as a result of their younger age.
Biodiversity loss worldwide – we cannot continue with a ‘business-as-usual’
An article published in Science (http://dx.doi.org/10.1126/science.aax3100) by authors of the Global Assessment of the IBPES (https://ipbes.net/news/global-assessment-summary-policymakers-final-version-now-available) warns of the continued over-exploitation of the earth’s resources which are vital for human societies. Evidence across scientific disciplines that was brought together for the report demonstrated unequivocally, that—like climate change—the loss of biodiversity on land, in freshwater and oceans impedes severely our possibilities towards achieving many Sustainable Development Goals. The declining trend in many indicators related to the integrity of natural ecosystems can be turned around through a number of integrated actions that include innovative governance approaches, as well as informed individual decision making.
Almut Arneth received a Distinguished Visiting International Fellowship under the Western Sydney University Vice Chancellor’s Research Fellowship Programme
She will be visiting the Hawkesbury Institute for the Environment at WSU in spring 2019 and 2020 to initial sustained cooperation and joint research activities with Australian colleagues on topics related to the role of terrestrial ecosystems and their management under land-use change and climate change.
A team of researchers including some of our team’s members has published a study titled “The role of global dietary transitions for safeguarding biodiversity” in Global Environmental Change (https://doi.org/10.1016/j.gloenvcha.2019.101956). The study emphasises that diets low in animal products reduce agricultural expansion and reduce agricultural intensity in biodiverse regions.
Land and land management is critical to keep global warming to well below 2ºC
The IPCC approved and accepted Climate Change and Land: an IPCC special report on climate change, desertification, land degradation, sustainable land management, food security, and greenhouse gas fluxes in terrestrial ecosystems at its 50th Session held on 2 – 7 August 2019 in Geneva. The approved Summary for Policymakers (SPM) was presented at a press conference on 8 August 2019. Almut Arneth was Coordinating Lead author of chapter 1 in the report and participated in the IPCC plenary session.