By Alina Paul-Bossuet
Droughts are becoming more frequent, particularly in regions where smallholder farmers are already struggling to get good harvests and grow enough for their family’s needs. Last year the drought in East Africa hit the headlines with its heavy toll on human lives. Now it is the Sahel region that’s suffering.
How can we anticipate what damage changing weather patterns will have on food production on small farms where families are least equipped to survive massive crop losses? A group of experts on climate, agriculture and economics have come together to address this question through the Agricultural Model Intercomparison and Improvement Project, or AgMIP which aims to assess climate impacts on regional and global food security now and in the future.
As part of this scientists are using computer models to understand how crops such as sorghum and peanut, which are vital to many smallholder farmers in Africa and Asia, are vulnerable to the changing climate.
“Climate change – warmer temperatures, and possibly less rainfall – may make a vulnerable region even more vulnerable to the weather,” says Cynthia Rosenzweig, a climate scientist at Columbia’s Earth Institute, who is co-leading the project.
But what do we mean by vulnerable? Of course a reduced crop yield due to warmer or dryer weather (where farmers rely on rain to water their crops) clearly affects a farmer’s food security and income. But warmer weather could also lead to increased pest attacks and fungal infections which could have serious health and economic consequences.
For example, the occurrence of aflatoxin, a deadly fungus that attacks staple crops like peanut, millet and maize, is strongly influenced by weather during and after the growing season. An increase in hot and dry spells would increase the risk of aflatoxin contamination.
Exposure to aflatoxin through consuming contaminated food is common and at high levels in sub-Saharan Africa and Southeast Asia, especially at the small subsistence farm level.
In young children exposure is associated with impaired growth and development, which is very prevalent in these regions. Studies in Benin and Togo showed that stunted and/or underweight children had 30 percent to 40 percent higher aflatoxin levels in their blood compared to children of normal height and weight. There is also a strong correlation between liver cancer and chronic aflatoxin contamination (a 5 to 60 times higher cancer risk).
Research shows that contamination levels can be significantly reduced when the right measures are put in place, such as improved drying and storage of the harvest and testing for aflatoxin levels.
So can climate and crop modeling help predict future toxin outbreaks and can seasonal forecasting prepare communities before and during the season to minimise aflatoxin contamination?
This is a question being studied by a team led by Andy Challinor , research director at Leeds University’s Africa College. He is working with the Consultative Group on International Agricultural Research (CGIAR) programme on Climate Change, Agriculture and Food Security (CCAFS), which is partnering with AgMIP to better assess the likely impacts of climate change on agricultural systems.
And what about dealing with crop losses due to droughts? Perhaps it’s worth mentioning a study of soybean farms in the US, given the drought hitting the country at the moment. Could changing to more drought tolerant crop varieties be a solution? A simulation over 50 years showed that the water conservation traits of drought-tolerant soybean resulted in yield increases in many locations in more than 70 percent of years.
We need to have similar predictions for drought-prone regions in the world’s southern countries, to help plan coping methods.
A team led by Vincent Vadez, a scientist from the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), is currently studying the effect of drought adaptation traits on the yields of groundnut, cowpea, chickpea and beans in key African countries.
The study covers a large part of the West African Sahelian zone and a large region of Eastern Africa (from Ethiopia down to Zimbabwe and Mozambique) and researchers will use the results to prioritize successful traits to breed for to prepare farmers for the future.
The results of crop and climate modeling could make a big difference to farmers – but only if breeders target useful traits (such as water conservation and pest resistance) and farmers can use the resources, advice and recommendations to change their practice.
“A major challenge is exchanging information between different scientific disciplines and taking the results of the climate, crop and economic modeling to the farm level” says Lieven Claessens, an ICRISAT scientist and part of the AgMIP project in Nairobi.
“Farmers and other stakeholders (national researchers, extension workers, NGOs and policy makers) have to be involved from the beginning to make sure the strategies and practices that are simulated with the models are feasible and can eventually be adopted by farmers to prepare for climate effects,” he adds.
Effective partnerships with those working with farmers in the region are essential to ensure that AgMIP has an impact on those vulnerable to climate change. Researchers, policy makers, extension services and NGOs are valuable partners to enable farmers to use the modeling data and adaptation strategies.
UK aid from the Department for International Development means that AgMIP will now include interdisciplinary teams in sub-Saharan Africa and South Asia. This is aimed at building capacity in the regions where small scale farmers are most vulnerable to climate change. That’s a big and must-have step if we want to make sure that crop modeling information and coping mechanisms have a real and useful impact on those worst hit by the weather.
Alina Paul-Bossuet is a communications specialist for the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT).