‘Transformative changes’ needed to counteract nature’s decline, IPBES Global Biodiversity Report warns
09 May 2019
A landmark report on the state of global biodiversity was released this week by the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES). Compiled by 145 international leading experts, the report assesses changes over the past five decades, providing a global picture of the impact of economic development on nature and warning that climate change will not be halted if we carry on degrading the soil.
The study highlights the unprecedented rates of nature’s decline and species extinction, as well as the grave impacts on the world’s population. It also offers a range of possible scenarios and recommendations for the coming decades.
More than 75% of Earth’s land areas are degraded
According to the report, more than 75% of Earth’s land areas are substantially degraded, undermining the well-being of 3.2 billion people. Rapid expansion and industrial management of croplands and grazing lands is the main driver of land degradation, causing significant loss of biodiversity and impacting food security, water purification and energy provision. Around 1 million animal and plant species are now threatened with extinction, more than ever before in human history. Since 1980, greenhouse gas emissions have doubled, raising average global temperatures by 0.7 ˚C – with climate change already impacting nature from the level of ecosystems to that of genetics. The report also finds that current trends in biodiversity and ecosystems will undermine progress towards 80% of the targets of the United Nations Sustainable Development Goals, related to poverty, hunger, health, water, cities, climate, oceans and land. More than ‘just’ an environmental issue, loss of biodiversity is also linked to developmental, economic, security, social and moral concerns.
The role of microbiology
Professor Penny Hirsch, Research Scientist at Rothamsted Research, read the report for the Microbiology Society. She commented that while the report highlights the importance of micro-organisms for human health, as well as marine and aquatic ecosystems, the importance for soil quality is identified as a ‘knowledge gap’. She also highlighted that while not mentioned explicitly, “indirectly, the importance of micro-organisms is a core part of this report. For every large charismatic mammal, rare plant, or obscure invertebrate that becomes extinct due to climate change or habitat loss, an associated microbiome is also lost. Any attempts to reintroduce captive-bred descendants will be hindered if they lack the microbiome needed to resist colonisation by parasites and pathogens present in their natural habitat”. Professor Hirsch also highlighted that degradation of soil reduces the abundance and diversity of the soil microbiota and may reduce the provision of services for general environmental functioning and agricultural crop production. Widespread cultivation of plant monoculture, she explains, “reduces microbiome diversity, making crops more susceptible to fungal and bacterial pathogens”.
Report offers a framework for transformative change
According to the IPBES report, transformative changes and a wide range of ambitious solutions are required in sectors such as agriculture, forestry, marine systems, freshwater systems, urban areas, energy and finance to safeguard life on Earth as we know it. For developing regions, the cost of inaction in the face of land degradation is at least three times higher than the cost of action. And the benefits of restoration are 10 times higher than the costs.
Micro-organisms are part of the solution for the need to increase agricultural sustainability, Professor Hirsch explains. For example, growing more legumes which form nitrogen-fixing root nodules containing rhizobia (symbiotic bacteria that can be applied to seeds or soil) can alleviate the need for nitrogen fertilisers and provide protein-rich crops. Some bacteria and fungi can be applied to crops to counter pests and diseases, reducing agrochemical use. Mycorrhizal fungi can be applied to improve the root systems of host plants. Better knowledge of these systems together with careful soil and crop management will help to optimise these valuable microbial interactions.
Soil microbiomes are large and diverse, with a range of bacteria, archaea and fungi capable of contributing to ecosystem services, Professor Hirsch notes. However, when stress is applied – such as flooding, drought, increased temperatures, application of excessive fertilisers and agrochemicals, or xenobiotic pollution – she explains that the system may be less able to respond: “Even in pristine conditions, environmental changes such as rising temperatures leading to melting permafrost leads to wet, organic-matter-rich soils releasing the greenhouse gas methane (along with nitrous oxide, if nitrogen levels are high). This shows that careful stewardship of our planet and its biota to minimise damage to the soil ecosystem and limit climate change is imperative”.
A summary of the report and other resources are available on the IPBES website.
The Microbiology Society is embarking on an ambitious project that will demonstrate the value and raise the profile of microbiology in addressing the world’s biggest challenges. Find out more about the ‘A Sustainable Future’ project.
Thanks are due to Professor Penny Hirsch for her analysis of the IPBES Global Biodiversity report. Penny led a group working on soil microbiology and molecular ecology at Rothamsted Research, the longest running agricultural research institute in the world. She has worked on mechanisms of gene transfer and antibiotic resistance elements in soil, and on mycorrhizal and nematophagous fungi.