According to the Food and Agriculture Organization of the United Nations (FAO), around one-third of the island’s land resources are degraded – mostly due to erosion.
Scientists from Madagascar’s National Institute of Nuclear Science and Technology (INSTN Madagascar) used an isotopic technique to evaluate the level of soil erosion and then used the results to advise farmers in similar situation across the country.
Erosion does not only deplete the soil, but at the same time impacts terrestrial ecosystems and their biodiversity, and when the eroded soil ends up in rivers and lakes, it affects the viability of aquatic ecosystems as well. It is therefore important to establish effective conservation strategies.
The studies have revealed that on cultivated land in the country’s Central Highlands over 10 tons/hectare of soil are lost on unprotected slopes every year as a result of a combination of farming practices, the lack of land cover and natural causes such as wind and heavy rain. The solution the INSTN researchers recommended to farmers was to switch to terrace farming, in which measurements revealed the loss of fertile soil was only 5 tons per hectare per year.
Officers from the Ministry of Agriculture are now working directly with highland farmers on implementing conservations strategies based on these findings.
“There are many ways in which the IAEA, through its technical cooperation programme, is assisting Madagascar in the use of nuclear techniques for development, in support of the government’s priorities,” said Abdou Ndiath, the IAEA Programme Management Officer working with the country’s government. “Addressing land degradation challenges brought about by soil erosion is among the most important fields of cooperation.”
Farmers in Madagascar’s highlands have always been rotating their crops to maintain the nutrient level of their plots, but now they know that at least once a year they need to grow sweet potatoes or beans, plants with extensive roots that not only keep much of the soil in place but after they have decayed enrich soil with carbon and provide a more dense structure to the soil, slowing down erosion.
Original source: IAEA
Published on 14 January 2019