Increased drought and wildfire risk make grass pasture more reliable as carbon sinks than trees.
Forests have always played a critical part of our environment as carbon sinks, consuming about a quarter of the carbon dioxide pollution produced worldwide. But decades of warming temperatures and drought have increased wildfire risks which in turn have the potential to change forests from carbon sinks to carbon sources.
Studies have shown that grass pastures can store more carbon than forests because they are impacted less by droughts and wildfires and this doesn’t include the potential benefits of good land management to help boost soil health and increase carbon stocks in grass pastures.
Carbon released in fires
Unlike forests, grass pastures sequester most of their carbon underground, while forests store it mostly in woody biomass and leaves. When wildfires cause trees to go up in flames, the burned carbon they formerly stored is released back to the atmosphere. When fire burns grass pastures, however, the carbon fixed underground tends to stay in the roots and soil.
In a stable climate, trees store more carbon than grass pastures. But with global warming and a drought-likely future, we could lose some of the most productive carbon sinks on the planet from the extreme weather changes that are beginning to occur all over the world.
We really need to start thinking about the vulnerability of ecosystem carbon, and use this information to plan our conservation strategies into the 21st century and grass pastures continue to store some carbon even during extreme drought simulations.
We are not suggesting that grass pastures should replace forests on the landscape or diminish the many other benefits of trees. Rather, that, conserving grass pastures and promoting good farming practices that promote reliable rates of carbon sequestration could help meet emission-reduction goals.
Trees and forests are an ecological necessity but when you put them in assuming they’re carbon sinks and trading them for pollution credits (ETS) while they’re not behaving as carbon sinks, emissions may not decrease as much as we hope.”
There’s a climate change solution beneath our feet
There’s too much carbon in the atmosphere and not enough in the ground where it’s useful.
When we think of climate change solutions, what typically comes to mind is the transportation we use, the lights in our home, the buildings we power and the food we eat. Rarely do we think about the ground beneath our feet or, more precisely, the soil.
Healthy soils can not only create productive farmlands, but also store carbon in the ground, where it belongs, rather than in the atmosphere as carbon dioxide.
Looking at a farm landscape most people would simply see bare fields. But in fact the fields themselves are living beings brimming with potential. The soil beneath the fields doesn’t just hold living things—it is itself alive.
The soil is like the human body with its own system of “organs” working together for its overall health. And, like us, it needs good food, water and care to live up to its full potential.
With soil, there’s so much going on that is so close to us, that’s so interesting and multifaceted, that affects our lives in so many ways — and it’s just lying there beneath our feet.
Farmers and gardeners have long sung the praises of good soil. For the rest of us, it’s practically invisible. But a greater awareness of soil’s ability to sequester carbon and act as a defense against climate change is earning new attention and admiration for a resource most of us treat like dirt.
Soil can potentially store between 1.5 to 5.5 billion tons of carbon a year globally. That’s equivalent to between 5 and 20 billion tons of carbon dioxide. While significant, that’s still just a fraction of the 32 billion tons of carbon dioxide emitted every year from burning fossil fuels.
So soil is just one part of a much greater number of integrated solutions needed to confront climate change.
But the nice thing about healthy soils is that creating them not only helps fight climate change, it also brings multiple benefits for agricultural, human and environmental health.
Underground, an invisible ecosystem of bugs or micro-organisms exists. In fact, there are more microbes in one teaspoon of soil than there are humans on Earth. Many of them lie dormant, just waiting to be properly fed and watered.
A well-fed army of microbes can go to work strengthening the soil so it can grow more food, hold more water, break down pollutants, prevent erosion and, yes, sequester carbon.
Soil sequesters carbon through a complex process that starts with photosynthesis. A plant draws carbon out of the atmosphere and returns to the soil what isn’t harvested in the form of residue and root secretions. This feeds microbes in the soil. The microbes transform it into the building blocks of soil organic matter and help stabilize the carbon, sequestering it.
You can’t sequester carbon without microbes, they’re far more important than we ever imagined.
There’s too much carbon in the atmosphere and not enough in the ground where it can be used.
The farmers should follow farming practices known to boost microbial communities underground and sequester carbon (such as using compost rather than fertilisers), to enhance their soils, to help reduce greenhouse gas emissions. Any increased demand for compost from farmers could also help reduce green waste going to landfills.
Similar to how people can feed probiotics and prebiotics to the microbes in their guts to improve their health, farmers can use cover crops and apply compost and other organic matter to feed microbes in the soil. Reduced tillage, efficient irrigation and other methods also strengthen the soil’s ability to store carbon.
Such techniques have long been used by farmers to enhance soil—particularly on organic and small farms.
This is ancient knowledge. When you increase organic matter in the soil, good things happen. But climate change is bringing new attention to it. Regardless of climate change, we should be doing this for many reasons—for productivity, erosion control, drought tolerance. It’s going back to our roots, no pun intended.
Sustainably managed farms suck up carbon by their mere existence.
The first thing to do to store carbon on farmlands is to avoid converting the farmland to other uses. But people are asking if there are additional things we can do to store carbon, like compost.
We lose many hectares of farmland each year, much of which becomes greenhouse-gas-emitting housing developments, shopping centres, roads and parking lots. But the remaining millions of hectares of farmlands nationwide—represent significant opportunities for additional carbon storage, and can help offset some of the emissions for which the meat industry is often criticized.
When people look at cows, they think of emissions, but the whole grazing system is actually sequestering carbon, yet the carbon sequestration from pasture is totally ignored when discussing emissions from farming.
It is only fair that if the discussions are to be held around the detrimental effects of farming on the environment, then the beneficial effects should also be part of the discussion to reflect the reality of the situation and bring some much needed balance to the discussions.
The world needs agriculture in all its different forms to ensure the population can be fed so any discussion should be based on science and include all of the relevant information that gives a realistic starting point when discussing rules around agriculture.
Unlike the current situation where the beneficial effects of agriculture have been totally removed from the discussion and there is no balance. The failure to include the beneficial effects, (from carbon sequestration in pasture through to security of food supply and reduction in food miles) highlights the inequity in the current discussions where agriculture is being unfairly portrayed as a destroyer of the natural environment, when in actual fact it is no worse or better than other parts of society as we see it today.
There are so many opportunities in agriculture to influence climate change. We should view soil as one example. Soil is easy to ignore. Although it’s everywhere, in most people’s consciousness, it’s nowhere (i.e. it’s ignored). So the challenge for the farming industries is to make people aware that the soil underfoot is alive, and that by using good farm practices we maintain or improve the soil whilst still ensuring security of food production.