Here is a good article on the emergence of agroforestry in Africa, exploring how trees on farms, biomass management, integration of natural fertilizers into agricultural systems is taking hold amongst small-holder farmers… Click the link at the bottom of the page to view the full article.
Soil care, fertiliser trees help African farmers grow yields
By Geoffrey Kamadi
RONGAI, Kenya (AlertNet) – Small farmers across sub-Saharan Africa are turning to simple, affordable techniques to increase harvests and help them cope with climate extremes – from growing trees on their land, to keeping their soils healthy and making their own fertiliser.
Nelson Mwangi has managed to boost the maize yield from his 0.3 hectare (0.8 acre) plot in Rongai, 170km from Kenya’s capital Nairobi, to 18 bags from around seven bags since adopting a method known as conservation agriculture three years ago.
“I have reached a position where I don’t need to use (chemical) fertiliser on my farm anymore because I have enough manure and compost,” says the 54-year-old father of four. The former agriculture teacher is now saving around KSH 3,900 ($46) in fertiliser and KSH 2,500 ($29) in labour costs each planting season.
Conservation agriculture involves minimum or zero tillage of the soil, keeping the earth permanently covered with organic matter, and rotating crops. Limiting disturbance of the soil ensures that it releases very little carbon dioxide and nitrous oxide – key greenhouse gases – into the atmosphere.
The use of harvested crop residue as soil cover helps retain moisture, meaning farmers are less reliant on rainfall. And when the residue decomposes, it enriches the soil further. Crop rotation helps control soil-borne diseases, reducing losses.
Increasingly, farmers are combining this approach with agroforestry, which involves planting leguminous tree species on the land.
As well as sequestering carbon, these “fertiliser trees” capture nitrogen from the atmosphere and fix it in the soil, boosting its nutrient content. As a result, farmers are less dependent on commercial fertilisers.