Getting Dirty on Climate Change
Last Friday Climate Change rallies spread across Asia into Africa and Europe, with school students joined by supporters of all ages. The global day of action was called ahead of a United Nations climate summit in New York this week. I fully support the cause, but question the depth of understanding and congruence between words and daily practices of the protestors:
· I wonder how many are prepared to pay more for sustainable energy, sustainable produce; sustainable clothing?
· I wonder how many buy the vast majority of their food from Coles, Woolworths or Aldi?
· I wonder how many argue for a plant-based world, but don’t know what poly-cultured farming is?
To meet the demands of a growing, increasingly urban global population (approximately 9 billion by 2050), the World Bank calculates that global food production must increase by 70% over the next 3 decades. This is a great challenge not only because of the volume of food that must be produced, but because agricultural conditions will not remain constant or predicable in the years to come.
An International Food Policy Research Institute report outlines opportunities for more productive and sustainable farming practices in the face of climate change. This report offered many important recommendations, but most notably highlighted the link between enhanced food security and climate-change adaptation. Sustainable farming has been shown to improve agricultural resilience and increase yields in climates where farming is historically difficult, and even help curb greenhouse gas emissions through practices like soil carbon sequestration. Such practices can not only help in terms of climate adaptation but can also be an invaluable driver in reducing poverty around the world.
In recent years, soil has been identified as an underutilised carbon sink, with a great potential to alleviate climate pressure. Soil is normally a significant carbon sink, but land use changes, such as conversion of native lands for agricultural use, reduces the soil’s potential carbon storage capacity. Some common agricultural practices, such as tilling, release carbon stored in soil. By contrast, periodically allowing soil to lie fallow leads to increased carbon sequestration.
More and more, scientists and researchers are exploring ways to restore degraded lands and replenish carbon and microbe levels for healthy soil. Carbon is an essential component of soil, giving it better water-retention, structure, and fertility. Improving soil quality around the world is an important step in achieving greater food security, especially in regions where vulnerable populations would benefit significantly from increased productivity and resilience.
One way to both increase crop yields and mitigate greenhouse gas emissions would be through soil carbon sequestration, which is the process by which atmospheric carbon is pulled into and stored in soil. Generally, high soil diversity and reduced disturbance can help maximise soil carbon sequestration. However, restoring degraded systems or preserving native lands are not the only means of enhancing a soil’s carbon storage capacity. Several well-known methods for environmentally responsible farming can help actively enhance storage while introducing other co-benefits as well. Of course, a combination of these methods would lead to the greatest benefit. Other methods should also be explored, as those highlighted below might not necessarily be suited for all countries or regions. Some methods to highlight include:
· No-till farming helps leave soil undisturbed and would protect sequestered carbon; meaning that it promotes carbon conservation in soil. This farming method is also known for preventing soil erosion, and in some regions, it has shown to help increase crop yields.
· Crop rotation, which involves the sequential planting several different crops on a plot of land, is a complimentary method to improve soil health. Not only does this method promote a strong balance of nutrients, this method can also reduce weed growth. In terms of carbon sequestration, rotational diversity can allow soil microbes to better process biomass residue that would then be stored in aggregates (stable soil structures that can protect carbon).
· Livestock is another important component of the agricultural industry and moving grazing herd animals from pasture to pasture can prevent over-grazing and land degradation. Restoring degraded lands through the introduction of manure could help improve soil quality, thereby improving its ability to store carbon.
· Perennial crops are those that can survive through multiple seasons and harvests, requiring less disturbance to plant new seeds. Perennial fields have shown to have higher root mass which allows for better introduction of carbon and nutrients back into the soil.
By introducing these sustainable farming methods in regions where a decline in agricultural would have the greatest negative effects on local populations, soil carbon sequestration could be an effective means of enhancing food security and addressing climate challenges.
Protests are great for your Instagram feed and for media outlets around the globe. The solution to climate change requires putting your money where your mouth is, starting with the food we eat.
Until next week, stay healthy