Nature paper shows crucial role of soil biodiversity in human health

The role of soil biodiversity in promoting human health is underappreciated, and poor land management practices and environmental change are endangering lives needlessly, according to a new Western Sydney University research paper published in Nature (opens in a new window). 

Co-authored by Dr Uffe Nielsen from the Hawkesbury Institute for the Environment, in conjunction with Professor Diana Wall of Colorado State University and Dr Johan Six of the Swiss Federal Institute of Technology, the Perspectives Paper (opens in a new window) outlines ten reasons why healthy and biodiverse soils are directly connected to human health.

"We are losing soils and soil biodiversity at a rapid pace, with substantial negative ramifications on human health worldwide," says Dr Nielsen.

"People understand that properly managing soils is key for the global food supply, and that soils are eroding. But less recognized is the role of living organisms in soils, and how management of those organisms benefits human health."

"It is time to properly recognize and manage soil biodiversity to achieve long-term sustainability goals related to global human health, because biodiversity in soils is connected to all life."

Dr Nielsen says a new approach towards soil is needed to recognize their centrality to human health, starting with the UN Sustainable Development Goals, which currently only mention soil in four of 17 targets. 

"It is not enough to aim towards improvement of a single benefit related to 'food' or 'air' or 'water' or 'disease' control, because all are simultaneously dependent on soils and soil biodiversity," he says.

The ten reasons healthy soils are crucial in human health and wellbeing:

• Biodiverse soils can help to control populations of disease-causing organisms – in healthy soil communities, disease-causing organisms such as listeria, salmonella and toxoplasmosis that infect humans are naturally controlled by soil-dwelling organisms.
• Healthy, well-covered soils can reduce disease outbreaks – keeping the soil covered with litter and vegetation is a well-known principle for maintaining soil health. This is also an effective approach for reducing the impact of diseases such as anthrax that can infect livestock and humans.
• Carbon-rich soils may reduce outbreaks of human and animal parasites – research from rural Cambodia found a higher risk of infection by roundworms in areas that had been cleared for crops where the soil carbon content had declined.
• Exposure to soil microbes can reduce allergies – inhabitants of urban areas have generally lower diversity of bacteria on their skin and lower immunity expression, meaning that exposure to soil microbes can promote immune health.
• Soils have provided many of our current antibiotics and pest-control agents – losses of soil biodiversity may reduce sources of future agents. Already, researchers have found promising soil bacteria that act against tuberculosis bacteria.
• Soil organisms can provide biological control agents – researchers are turning to soil-dwelling organisms such as nematodes, bacteria and fungi to safely control other pests and diseases in crops, a better approach than relying on synthetic pesticides.
• Healthy soils mean healthier foods and more of it – biodiverse soils can promote better nutrient and water uptake by plants, which means that food is richer in nutrients essential to human well-being.
• Soil microbes can enhance crop plant resilience – in difficult seasons, the health of the soil can dictate whether or not the crop can survive to produce a good yield. New research demonstrates how reliant many crop plants are on soil fungi and bacteria.
• Healthy soils promote good clean air quality – we all remember the incredible red dust storm of 2009 in Australia. But healthy soils are also more stable soils that produce more plant cover and are less prone to wind and water erosion.
• Healthy soils provide clean and safe water – soils provide many benefits in delivering clean water to our populations, through filtration, decontamination by microbes and removal of pollutants. Our water cycle is very dependent on the ability of soils to support clean water collection.

Ends

24 November 2015

Mark Smith, Senior Media Officer