Soil transformations triggered by global warming

Impact of Global Warming on Soil Transformations

In a recent study published in the journal "Proceedings of the National Academy of Sciences", a team of researchers, led by Matthew Nielsen from the University of Bremen and colleagues from Sweden, have shed light on the significant and potentially alarming effects of global warming on soil microbial diversity.

The research reveals that a temperature increase of just 2.3 degrees Celsius in experiments resulted in a reduction of bacterial diversity by 16.0% and fungal diversity by 19.7%. This finding is particularly concerning as diverse communities of microbes play a crucial role in the soil ecosystem, using carbon more efficiently and investing more in biomass production rather than respiration, promoting carbon storage.

Previous studies had shown varying effects of global warming on biodiversity, but this new study presents a consistent picture of negative impacts on microbial diversity in soil. For the warmest climate scenario, the researchers predict that bacterial diversity in soil may decrease by 56% within 60 years, and fungal diversity could decrease by 81%.

The effects of global warming on microbial diversity are not limited to specific ecosystems. The team's findings suggest that these effects are similar in farmland, forests, and pasture. This means that the loss of microbial diversity could have far-reaching consequences, affecting not just the health of our soils but also the productivity of our agricultural lands and the resilience of our forests.

Heat-loving species are favoured in these warmer conditions, displacing cold-loving species, leading to reduced biodiversity in soil, farmland, forests, and grasslands. This reduction in microbial diversity could accelerate future warming, underscoring the urgent need to mitigate global climate change.

Soils are currently considered carbon sinks, but their storage capacity may decrease with increasing heat. Bacteria, which have higher metabolic rates in heat, break down more organic material into CO2, reducing carbon storage. This decrease in microbial diversity could lead to significant and widespread losses of carbon storage, exacerbating the effects of global warming.

The team emphasizes the importance of reducing climate warming to maintain soil carbon. They suggest the use of organic soil amendments and reducing chemical fertilizers and pesticides as potential strategies to help mitigate these effects.

Moreover, the findings suggest that the fungal community is more sensitive to heat than the bacterial community. This means that efforts to protect and preserve fungal diversity could be particularly important in the fight against global warming.

The study also highlights a potential cost for farmers. Temperature increase may lead to higher costs for farmers, with one study showing that a farmer may lose 5% of their crop per day due to temperatures. This underscores the need for sustainable farming practices that can help adapt to and mitigate the effects of global warming.

In conclusion, the study provides a clear picture of the negative impacts of global warming on soil microbial diversity. These findings underscore the urgent need for action to reduce climate warming and protect our soils, not just for the health of our planet, but for the future of our agriculture and food security.