Scientists agree – the world’s been a bit warmer lately. The ten hottest years on record have all occurred since 1998, with 2016 ending as the second-hottest year on record.
The changes come in small increments – often measured in tenths of a degree. For example, since 1895, the contiguous United States has seen an average temperature increase of just 0.15°F per decade. But a group of Australian researchers are interested in whether these subtle changes are creating subtle effects on soils.
In particular, the scientists looked at how soil organic carbon could be altered by climate change.
“Soil organic carbon is a major determinant of soil health,” according to Johnathan Gray, the study’s lead author and senior scientist at the New South Wales Office of Environment & Heritage. “It influences many chemical, physical and biological properties of the soil, such as fertility and water-holding capacity.”
Researchers ran 12 climate change models to predict how soil organic carbon levels would react to changing climatic conditions. They anticipated antagonistic results, but the results did not all come in as expected.
“A majority of the models showed a decline in soil organic carbon with climate change,” Gray says. “But a few of the models actually predicted an increase.”
More work needs to be done before they make any firm predictions, Gray adds. But it’s vital work, he contends.
“This knowledge can help us to better understand and predict where the greatest potential losses or gains in soil carbon may occur,” he says. “It would allow us to better prepare for and adapt to altered soil conditions. That would ultimately improve how we manage both agricultural and native ecosystems.”
The study was published in Soil Science Society of America Journal.