- Soil acidification strangling crop productivity on three million hectares.
Officials at the Ministry of Agriculture have finally received the go-ahead to use a portion of the federal fertilizer subsidy budget to lower costs for lime needed to remedy acidic soil threatening farm productivity in many parts of the country.
Lime (calcium carbonate) is used to neutralize acidic reactions and ions that build up in the soil as a result of farming, particularly with the use of nitrogen fertilizers such as urea. The Ministry plans to allocate 1.4 billion birr to subsidize lime costs for farmers this year, looking to heal 300,000 hectares of farmland that has seen productivity plummet as a result of soil acidity. It is a fraction of the 3.1 million hectares thought to require lime treatment in the country.
Eyasu Elias (PhD), a state minister of Agriculture, told The Reporter he and his peers at the Ministry needed to convince Parliament, the Finance Ministry, and senior Prosperity Party officials to approve the budget for lime subsidies, which was originally part of the budget for fertilizer subsidies.
“Budget allocation for lime subsidies have been delayed because the budget earmarked for lime has been diverted to subsidize fertilizer. Fertilizer has become more expensive, so its subsidy has been taking up a large budget. Now, we’re preparing to launch a comprehensive campaign to treat acidic soil,” said Eyasu.
More than three million hectares in Ethiopia, including in parts of Oromia, Amhara, Sidama, Benishangul-Gumuz, and the Southwestern regions, are classified as having strong acidity (pH value between 4 and 5). A further 17 million hectares is thought to be slightly acidic (pH value between 5 and 6).
In addition to chemical fertilizers, heavy rainfall can hasten soil acidification by washing away useful nutrients such as calcium, magnesium, and sodium.
Although some crops can tolerate soil acidity to a degree, many, such as barley and potato, do not grow at all in acidic soil. It is also thought to reduce wheat productivity by up to 70 percent, and corn (maize) by 30 percent. Acidic soil generally lowers productivity by a 50 percent average across all crop types. However, crops like tea and coffee prefer acidic soil.
“Ethiopia is losing a substantial amount of productivity due to acidic soil. We must heal the soil with all available resources we have,” said Sofia Kassa (PhD), a state minister of Agriculture.
Agricultural experts warn that acidity can neutralize the growth-promoting effects of chemical fertilizers. It takes 30 quintals of lime to heal, or alkalize, one hectare of farmland. One round of lime application, prior to sowing, can keep soil acidification at bay for up to five years as the calcium in the lime rock takes years to leach into the ground.
The government will source close to nine million quintals of lime from eight state-owned production plans to treat 300,000 hectares. There are also efforts underway to source lime from cement factories, according to Eyasu.
“We decided to start with 300,000 hectares this year because there isn’t enough in the budget for subsidies,” he told The Reporter.
Alkaline (basic) soil is also a problem in Ethiopia, where nearly 13 million hectares of land are thought to be affected. The prevalence of basic soil, which is also detrimental to plant growth, is related to the misuse and overuse of irrigation.