Soil Erosion control
One of our big projects is in the Enyezini area, where we also support several girl child students in their education. The area suffers from erosion through deforestation in the last 50 years. Pressure on forest is high due to increasing demand of a growing population. According to a study of the UNEP, the agricultural productivity of Malawi is being reduced by 6% annually due to soil removal through erosion processes. This is a devastating trend as nearly all food that Malawians consume is being produced by local farmers. The tragedy of climate change shows that most of the time people who have not contributed to burning fossil fuels in a meaningful way are the ones who suffer the most as extreme weather events get more common: every year we receive reports about increasing rainfall and downpours destroying bridges and roads and obviously removing top-soil layers in fields and open canopy forest environments, especially if already in a disturbed state.
"A 2011 Poverty-Environment Initiative study estimated that if soil erosion would be tackled 1.88 million people could have been lifted out of poverty between 2005 and 2015."
It seems obvious that one should tackle soil erosion to improve the livelihoods of communities in the most impacted areas.
As we are not experts on soil erosion we found them in Ken Coetzee and his excellent team from Conservation Management Services from South Africa. We invited them to visit the project and they spent about 10 days there and taught all our project managers as well as 50 workers in the Enyezini Community how to tackle soil erosion, as well as the root causes of it.
What is soil-erosion? – in less than 60 seconds
If heavy rain hits the ground and is not being slowed down through vegetation, the top soil and the litter layer can be easily washed away. If small streams form in steeper terrain they wash away even more soil in their tiny riverbeds, creating erosion channels and gullys.
The negative impact of soil erosion is visible in the most important seasons for a plant: the rainy, as well as the dry season: As most of the rainwater is not being absorbed the remaining moisture in the dry season that is available for a plant is often too little to have a satisfactory growth speed. This impacts crop production, as well as the planting indigenous trees project. So what can we do about it?
The Basic idea of stopping soil erosion is to reduce flow speed of surface water. This can be achieved by multiple means: Planting trees, shrubs and grasses helps to prevent soil removal. Depending on the terrain there are a multitude of different measures that can be taken, the beauty of the applied methodology in Enyezini is that only locally available materials are being used making the whole strategy applicable in all areas within Malawi.
In relatively flat areas, wide and deep holes are being dug, and a branch-packing is being applied. In the rainy season they capture a lot of water, which then slowly gets absorbed by the soil. At the bottom of these holes moisture levels will remain high and allow for high growth rates and good survival of planted species or germinating dormant seeds.
In areas with smaller streams dam-like structures are being installed with the goal of reducing the stream flow and capturing soil particles that were washed away. This may not seem like much, but it prevents the erosion of downstream areas.
If a hill has no vegetation cover whatsoever it is helpful to apply mulch with smaller fences in between to slow down water runoff speed even further. Grasses are much more likely to survive under these conditions as well as other pioneer species.
Smaller gullies can be sloped, and denaturalized: a labour-intensive task. Here we see a before & after photo of the same area.
Lovemore (our Planting indigenous Trees Manger) has reported that our local managers have taught these methods to people in other areas as well and very pleasingly, locals are taking up these strategies and are implementing them on their lands.