Microbial carbon sequestration is one of the most important scientific endeavours of the 21st century. It promises an elegant solution for two of our greatest challenges: climate change induced by the increase of CO2 in the atmosphere, and the decrease of fertility and resilience in the world's agricultural soils.
A pathway from sky to soil
Compared with other carbon sequestration mechanisms, microbial processes are by far the most efficient way of capturing carbon. There is no requirement for additional equipment, land or energy for the sequestration process.
Farming for soil health
Today's methods of agricultural soil management can dramatically influence soil organic carbon (SOC) but with unpredictable outcomes. This is mainly due to varied rates of decomposition and respiration of a substantial portion of root exudate and soil material releasing it back to the atmosphere as CO2.
Supporting the crops
Endophytes are microbes that live symbiotically within plant tissue for at least part of their life cycle. Groups of these endophytic microbes, such as mycorrhizal fungi and nitrogen‐fixing bacteria, have long been known to benefit plant growth. Other endophytes living in plant tissues have been shown to increase fertility, promote plant growth and give protection against stresses such as disease, drought and temperature extremes.
Long-term stable carbon storage
Some microbes, for example melanised endophytic fungi, feed on the plant root exudate which contains labile carbon compounds and produce melanin. This is a more stable polyaromatic carbon compound that is resistant to being broken down by reaction with water in the soil. In addition, it has been shown that this carbon is deposited in tiny compressed balls of soil called soil micro-aggregate. These micro-aggregates provide an anaerobic home where carbon can be safely stored long term.
The application of associations of microbial organisms, including melanised endophytic fungi, is an efficient method of increasing natural carbon deposits in soil. In a fungal-bacterial consortia melanising fungi can be grouped together with other microbes to create plant benefits. This method also creates a long-term increase in stable soil organic carbon drawn down from atmospheric CO2.