Breaking Ground: Santiago LĂłpez-Ridaura supports farmers facing tough decisions
Farmers frequently encounter trade-offs between maximizing short-term profits and ensuring sustainable, long-term production. Santiago LĂłpez-Ridaura, a senior scientist at the International Maize and Wheat Improvement Center (CIMMYT), says these trade-offs are even more complicated for small-scale farmers who grow a mix of crops and raise livestock. With computer models to play out different scenarios, he and his team are helping them find optimal solutions.
âIf you have $100, one hectare of maize, a half hectare of beans and three cows, you have limited resources,â indicates LĂłpez-Ridaura. âYou have to decide how you allocate those resources.â
Should the farmer use the money to buy new equipment or vaccinate the cows? What would happen if the farmer replaced the half-acre of beans with maize? These trade-offs, LĂłpez-Ridaura explains, are one aspect of a farming systemâs complexity.
âThe other is that these farmers are trying to satisfy multiple objectives,â he adds. âThey want to generate income. They want to produce enough food to feed their family and they may be trying to maintain cultural values.â
For example, a hybrid maize variety may produce higher yields under certain growing conditions, but the farmer could decide to continue growing the native variety because it carries cultural or even religious importance. Seasonal migration for off-farm jobs, climate change and access to markets are just some of the other factors that further complicate the decision-making process. LĂłpez-Ridaura points out many models in the past have failed to capture these complexities because they have focused on one objective: productivity at the plot level.
âOur models show the bigger picture. They take a lot of time to develop, but theyâre worth it,â says LĂłpez-Ridaura.
Custom solutions to farming challenges
The models start with hundreds of in-depth household surveys from a specific region. LĂłpez-Ridaura and his team then organize the large pool of data into several categories of farming systems.
âWe make a model that says, âOK, this farm in Oaxaca, Mexico, has five hectares, 20 sheep and five people,â he explains. âWe know how much the animals need to eat, how much the people need to eat, how much the farm produces and how much production costs.â
He and his team can then adjust certain factors in the model to explore different outcomes. For example, they can see how much water the farmer could use for irrigation to maximize his/her yields without depleting the local water supply during a drought. They can see which farmers would be the most vulnerable to a commodity crop price drop or who would benefit from a new policy.

âThe political guys often want a simple solution so they may say, âWe should subsidize inputs such as seeds and fertilizers.â In Mexico, for example, you might miss 60-70% of farmers as they donât use much of these inputs,â LĂłpez-Ridaura says. âSo thatâs great for 30% of the population, but why donât we think about the other 70%? We must be able to suggest alternatives from a basket of options, considering the diversity of farming systems.â
LĂłpez-Ridaura emphasizes that the models on their own do not provide solutions. He and his research team work with farmers to learn what they identify as their main challenges and how best to support them.
âWe have networks of farmers in Guatemala and Oaxaca, and some may say, âWell, our main challenge is being self-sufficient with forage crops,â and weâll say, âOK, why donât we try a crop rotation with forage crops? Our model suggests that it might be an appropriate option.ââ
He and his team can then help the farmers access the right kind of seed and find out how best to grow it. This relationship is not a one-way street. The farmers also provide feedback on what is or is not working on the ground, which helps the researchers improve the accuracy of their models. This approach helps the researchers, farmers and policymakers understand different pathways forward and develop locally adapted, sustainable solutions.
Santiago LĂłpez-Ridaura and his team work in Africa, Latin America and South Asia. Their funding often comes from development agencies such as IFAD and USAID.