So, you want to help fight climate change? Start at the root
Written by Brendon Anthony, Co-founder and CEO of Harvest Craft
Emissions from the burning of fossil fuels that power most of our homes, transport and offices are warming up our atmosphere like additional wool in a sweater, insulating and raising the global temperature of our air and oceans to a near catastrophic level.
But there is a way to return this carbon back to below the Earth’s surface. It is happening 24/7, every day of the year, all around the world and you are currently benefitting from it right now as you read this. It’s called photosynthesis. Nothing earth-shattering, you might think, but biological organisms, like plants, can be leveraged to not only convert CO2 into oxygen that we can breathe, but convert it into carbon compounds that can be stored.
In other words, oxygen is merely a by-product of the fascinating conversion of plants harnessing carbon dioxide and water. They are able to create compounds that first help the growth of its plant material – leaves, fruits, flowers – and then send these carbohydrates down into the soil. This helps build an incredible resource that is all too often overlooked: soil organic matter (SOM).
“Glue” in the soil
Soil organic matter is just a fancy word for carbon in the soil but it acts as a vital component to the soil’s ecosystem. It acts like “glue” in the soil, helping to retain moisture and nutrients vital for plant growth. It also gives soil texture and helps hold it all together, so when rains or winds come, it doesn’t wash or blow away. In other words, maintaining SOM ensures the life-giving capacity of the soil and also mitigates the effects of climate change by storing carbon in the soil, as opposed to leaving it in the air. So, how do we add more SOM back into our lands? Well it requires a change in our agricultural practices, while restoring natural ecosystems.
There are two main ways SOM is lost and released back into the atmosphere in the form of CO2. The first is tillage, a cultivation technique that essentially churns and blends up the soil to eliminate weeds and remaining crop, while creating a fresh layer of top soil for seed planting in the subsequent season. The plant material is not left to decompose into the soil, but instead its carbon is emitted back into the atmosphere. The second way SOM is lost is through soil erosion, where the soil itself is just washed away, especially when agriculture is taking place on steep hillsides.
Trees can act as a natural barrier for the soil
Soil erosion is a complex issue and is not exclusive to any agricultural region. However, in tropical areas where heavy storms and hurricanes are in high frequency, this can lead to accelerated erosion. The eroding impacts of these storms are only intensified when vast issues, such as deforestation, are also present in these areas exacerbating the problem.
Why? Because trees can act as a natural barrier for the soil, with the heavy rains hitting the canopy, instead of directly hitting the ground. This buffer helps eliminate the pressure of erosion. Additionally, the vast network of tree roots also helps to maintain the soil’s integrity, not to mention the tree’s capacity to also sequester carbon and build up SOM. This is why global reforestation efforts are a key solution in helping to mitigate climate change and restore balance to natural landscapes.
Haiti’s soil crisis
Deforestation coupled with natural disasters is a major issue in Haiti. The lack of tree cover in the mountains, as well as the removal of mangroves along the coastline, create an extremely exposed and vulnerable landscape when hurricanes do occur. Farmers are also growing food along steep hillsides (often the cheapest land available), tilling the land for ease of maintenance and creating a potentially devastating situation, both in the short and long term. The short-term impact may be the loss of this year’s yield when a storm comes, but the issue of losing their soil to erosion presents negative long-term impacts. The loss of soil is an economic and social issue to the subsistence farmers in these regions who depend on their production. It’s also an environmental one as the loss of vegetation from the farmland negatively impacts biodiversity and the soil’s ability to sequester carbon.
Soil conservation must therefore be put at the heart of Haiti’s solution to reducing soil erosion and increasing canopy coverage through reforestation. One of the most inexpensive and effective ways to prevent soil erosion on these steep hillsides is to first create terraces to level the grade and second, plant vetiver (Chrysopogon zizanioides), a tropical bunchgrass, along the hillsides to act as a physical barrier for the escaping soil.
Soil saving miracle grass
Vetiver is a deep-rooted grass that grows quickly from cuttings and helps stabilise the soil. Its roots are widely known for their aroma and is most popularly used as a base-compound in many perfumes. It is widely grown in Haiti for this purpose, but its benefits go much further. Vetiver can be grown along terraces so its deep roots can help prevent soil from eroding, while drawing up nutrients from deep soil horizons which then get drawn back up to the grass. The grass can then be “chopped” and “dropped” back on top of the soil to act as mulch. The grassy mulch layer on top of the soil helps prevent weeds, retain soil moisture and slowly adds organic matter (via decomposition) to the topsoil, which enhances agricultural production and acts as a “sponge” for carbon storage.
Vetiver is an easy and effective mitigation strategy for soil conservation, and in turn helps farmers produce more food and helps the environment draw-down more atmospheric carbon back into the soil. In other words, this fragrant grass does much more than tantalise the senses. Vetiver provides huge economic, ecological and social benefits.
Solutions like these are providing short- and long-term benefits to farmers who are implementing them, while the soil is conserved, improved and built up. When the planet’s soil is strong, healthy and full of organic matter – carbon – it has the capacity to bolster food production and tackle climate change.
So, what can you do? Support farmers that support their soil. After all, it isn’t just dirt. It’s full of life and has the capacity to ensure a rich life to come, not just for plants, but for all of us.
Non-profit organisations based in Haiti are encouraging vetiver cultivation beyond its normal production area, in the South of Haiti. Harvest Craft, the operating organisation of the Haiti Center for Agroecology (HCA), hosts trainings each month with local farmers on how to shape terraces on contour for production along steep hillsides, while providing knowledge and plant material to propagate vetiver along their edges.