Soil carbon: the potential of Kenyan farmers to reduce greenhouse gas emissions and increase food production

• The Kenyan government aims to reduce carbon emissions by 32% in 2030, through the implementation of nature-based solutions (NBS).
• More than 200 countries, including Kenya, attending the COP29 Summit in Baku, Azerbaijan, have agreed on measures to direct carbon credits to NBS in developing countries and help reduce greenhouse gas emissions .
• The 2024 Global Carbon Budget report indicates that carbon emissions from fossil fuels and cement will increase by about 0.8% in 2024, reaching a record 37.4 billion tonnes.
• However, according to Jenny Luesby, managing director of FarmBizAfrica, the focus should be on soil carbon, where the numbers are overwhelming, rather than the oil and gas sector.

TUKO.co.ke journalist Wycliffe Musalia has over five years of experience in financial, business, technology and climate reporting, providing in-depth insight into Kenyan and global economic trends.

Baku, Azerbaijan – More than 200 countries, including Kenya, converged on the COP29 conference.

The 29th Conference of the Parties to the United Nations Climate Convention focused on measures to direct carbon credits to developing countries and help them reduce their greenhouse gas emissions.

Kenya, among other African countries, is among the beneficiaries of carbon credits which aim to reduce carbon emissions by 32% in 2030, through the implementation of nature-based solutions (NBS).

According to the Global Carbon Budget Report 2024, carbon emissions from fossil fuels and cement will increase by around 0.8% in 2024, reaching a record 37.4 billion tonnes.

Is soil carbon the solution?

However, in an exclusive interview with TUKO.co.keJenny Luesby, managing director of FarmBizAfrica, noted that the focus should be on soil carbon, where the numbers are overwhelming, rather than the oil and gas sector.

“We’ve focused all this time on oil, gas and methyl emissions, but in reality the numbers are tiny compared to what’s happening in the soil cycle,” Luesby said.

Luesby referenced the company’s recent analysis showing that Africa has the potential to capture more than 20 times global oil and gas emissions.

FarmBizAfrica has found that the continent could absorb up to 132 billion tonnes of climate change-causing carbon dioxide and save almost $2 trillion (KSh258.6 billion) annually in an effort up to here unsuccessful aim to offset carbon emissions from oil and gas by about $5 billion. billion tons.

The climate change consultant explained that the carbon cycle involves the soil receiving carbon from plants and releasing it into the air.

“What’s happening is that the carbon in the soil (black mineral carbon and organic carbon) is much more important than all the carbon in the air. Soil carbon escapes because we don’t grow enough crops to retain enough organic matter in the soil to replace the carbon. carbon dioxide coming out,” she noted.

Advancing Earth and Space Science, AGU, notes that soil carbon is essential to agricultural productivity and the terrestrial carbon budget. In addition to plant photosynthesis, the sequestration of atmospheric carbon dioxide (CO2) in the form of SOC constitutes a significant global carbon sink, with soils storing approximately twice as much carbon as is retained in the atmosphere.

Luesby clarified that soil carbon helps retain water and when it is less, the soil becomes more sandy and unable to retain water, leading to climate change effects such as land degradation, turning into droughts and eventually deserts.

“We need to return and retain organic and inorganic carbon in the soil. This helps retain water; without it, soils gradually turn to sand, moving towards eventual desertification,” she said.

How to restore and retain soil carbon

The FarmBizAfrica co-founder said soil carbon can be retained and reintroduced into the soil by growing indigenous crops.

These include millet and sorghum, which grow roots deeper and put more organic matter into the soil, retaining water.

She said soil carbon can be restored by changing what is grown, rotating crops and growing cover crops instead of exposing/not covering the soil for months after harvest.

These measures contribute to achieving a 1% increase in soil carbon. Studies show that every 1% increase absorbs 8.5 tons of carbon per acre per year,” Luesby noted

Kenya has 277,100 square kilometers of agricultural land, or 68.4 million acres. A 1% increase in soil carbon would capture 581 million tonnes of carbon per year.

In sub-Saharan Africa (10.5 million square kilometers of agricultural land), increasing soil carbon could capture 22.1 billion tonnes of carbon.

Is biochar the best way to retain soil carbon?

Most small-scale farmers in Kenya and Africa as a whole burn their agricultural waste in the open, which Luesby says is bad practice.

She explained that direct burning of plant waste exposes a lot of carbon to the atmosphere.

“Burning plant waste on the soil surface is really painful. This method burns all the organic carbon from the plants. Instead of composting it and mulching it to incorporate it into the soil, farmers send a mist of carbon into the soil. ‘air., leaving the soil bare, letting carbon dioxide from last season’s roots escape without replacement, and this is how our soil carbon continues to decline, making drier soils which can only function. with (expensive) fertilizers”, she noted.

However, she recommended digging a hole to burn the waste instead of burning it on the surface. This method (pyrolysis) produces biochar, a carbonized organic matter that enhances soil carbon, thereby improving productivity.

“There is no technical barrier, just dig a hole and burn your waste in it. This method does not draw oxygen into the combustion, thus creating biochar.” she added.

A Science Direct study shows that biochar adds 2.2 tons of carbon to the soil for every 9.9 tons of agricultural waste put into the biochar pit.

How biochar improves food productivity

Luesby cited a study conducted in Kenya by HAL, noting that biochar increases corn yield by more than 50%.

According to the report, Kenya’s average maize yield on smallholder farms is only about 1 Mg ha−1, which is lower than the national average and well below the yield of 6 to 8 Mg ha−1. 1 which could be obtained with recommended management practices.

“The crop yield gap is largely attributable to soil nutrient depletion caused by long-term nutrient extraction and land degradation, exacerbated by the old age and highly altered state of Kenyan soils , temporal and spatial variability of precipitation, and suboptimal agricultural practices,” the report reads in part.

It recommends adding biochar made from excess biomass waste to croplands as a potential strategy to improve food security, land management and climate change mitigation.

What are the challenges of adopting biochar?

The report reveals that this technique has not been studied extensively in smallholder farming systems in Kenya and Africa.

Luesby explained that the economic barrier to this lies in the lack of awareness among smallholder farmers.

She called for massive campaigns from relevant stakeholders, citing FarmBizafrica’s initiatives to raise awareness among farmers about biochar and its potential to improve food security.

“COP29 and governments should recognize this initiative and support farmers through carbon credits by prioritizing soil carbon, which is an effort towards sustainable agriculture,” Luesby recommended.

She said FarmBizAfrica is currently mobilizing and raising awareness among farmers about soil carbon and biochar, calling for extensive information campaigns and agricultural extension initiatives to end carbon emissions.

Jethro Tieman, CEO of FarmBizAfrica, said it was the right time for Kenya and other African countries to prioritize soil carbon for climate change solutions and food security.

“Our leaders tinker while Rome burns, but the consequences are of unimaginable magnitude. This is not about trading tokens on industrial emissions: now is the time to tackle soil carbon head-on and invest more in carbon capture in Africa than in the entire transition energy,” Tietman said.

The initiative is expected to be integrated into Kenya’s National Climate Change Action Plan (NCCAP) to reduce greenhouse gas emissions and ensure food security.

Source: TUKO.co.ke