Research News

Assessing Farmers’ Decision-Making under Water Scarcity Conditions

January 26, 2023

A new model to predict farmers’ behavior shows that farmers in coastal regions may be more influenced by social than economic factors when it comes to their farms and their willingness to adapt decreases as future water deficits increase. 

 

Worldwide, water scarcity is identified as one of the major threats to agriculture, particularly coastal agriculture. Future climate change is expected to increase the amplitude and duration of heat waves and lead to variation in rainfall patterns that could represent a serious threat to coastal agriculture and crop yields.

 

A research team led by Khalifa University’s Prof. Mutasem El Fadel, Chair of the Department of Civil Infrastructure & Environmental Engineering and Professor of Industrial and Systems Engineering, developed a model to predict farmers’ decisions concerning their future farming practices when faced with potential water scarcity induced by climate change. They published their results in the Journal of Environmental Management.

 

“We can expect that future climate change will have significant implications on the coastal landscape and threaten the sustainability of global food security, economic viability, and farmers’ livelihoods,” Prof. El Fadel said. “As such, it is imperative to shed light on farmers’ decision-making processes under water scarcity associated with projected climate change.”

 

Current theories assume that farmers are profit optimizers. Evidence shows, however, that experienced farmers tend to make economically viable decisions, while still considering their surrounding community, the weather, and their political background.

 

“Farmers are also known to assign great value to their farming lifestyle, family, community, work traditions, and experience,” Prof. El Fadel said. “Normative models, therefore, can misrepresent farmers’ decisions and are other unreliable descriptors of their reality.”

 

Social models, on the other hand, have been developed to account for farmers’ attitudes, intentions, beliefs, and norms in the decision-making process. These models recognize the complexity involved, relying on the social-psychology theory that there are two central drivers of human behavior — attitude and subjective norms — that affect decisions beyond profit optimization.

 

The research team wanted to develop a model that would highlight the importance of accounting for the socio-psychological variables when simulating farmer decisions.

 

“Agent-based models (ABM) are powerful tools that have evolved toward assessing decision-making, while explicitly accounting for spatial dependencies,” Prof. El Fadel said. “They are able to simulate actions and interactions between a series of agents and their environment and to map the ways of the mind. ABMs can equally account for a wide range of decision-making rules and have been successfully used to predict farmers’ decisions under different scenarios.”

 

The team tested and validated their model with farms located in Lebanon along the eastern Mediterranean coastline. Most of the land in this area is used for agriculture, of which 65 percent is banana production. It enjoys a Mediterranean climate, with warm and dry summers and moderately cold, windy and wet winters. Future climate models for the area, however, predict a decrease in precipitation and an increase in temperatures by 2030, suggesting a decline in water availability too. 

 

This is the scenario the team used to test their model. It highlights the potential impacts that the changes in water availability within the study area may have on the future landscape. Various predictions regarding the magnitude of the decrease in water availability were considered.

 

Under these parameters, using only strictly economic-based rules predicted that by the end of the simulation in 2032, the region would experience a 30 percent decrease in areas growing bananas, mainly along the northern end of the study area and near the shoreline. The model predicted that farmers would choose more economically attractive crops under these conditions to maximize profit, not accounting for the fact that banana farming is associated with local traditions.

 

The two most common predictions using purely economic rules were quitting farming without selling the land and changing the crop type. But when farmers’ decisions were based on optimizing the joint socio-economic options, the two most common decisions were changing the crop type and seeking a new water source.

“This highlights the impact that social values, traditions, and past incidences have, reflecting a compromise between the social values that aim to retain the land and the loss of economic profitability if the land is left barren,” Prof. El Fadel said.

 

When the drop in water availability was minor, a significant number of farmers tended to seek a new water source, either with or without changing their crop types. Changing crop type appeared to be the most feasible and economically viable decision when the drop in water availability was limited to 12 percent, indicating that farmers will try to adapt without giving up on farming.

 

As the projected decrease in water availability increased, so did the probabilities of selling and quitting. The less water available in the scenario, the less willing farmers were to adapt and keep farming. The researchers theorized this was due to the need to change to drought-tolerant crops, which they may have no experience in farming, or to expect more frequent crop failures. Additionally, willingness to seek an alternative water source appeared to wane when water availability significantly decreased. At this point, farmers preferred to sell their land and allow their fields to be urbanized. If water scarcity reaches the point predicted in the model — 48 percent less — the region could expect to see expanded urbanization and a limit to banana farming.

 

“Although we tested our model along the Mediterranean coastline, our model offers a generalized and nonspecific structure to allow its application in any agricultural setting,” Prof. El Fadel said. “Our framework provides a powerful management tool that can be used by coastal managers aiming to protect fragile coastal agriculture from the encroachment of urbanization. It can help in defining and testing the impacts of proposed policies and the effects of changes to the physical and social forcing on future farming decisions and the feasibility of preserving coastal agriculture.”

 

Jade Sterling
Science Writer
26 January 2023