Incorporating trees onto cropland can sequester large amounts of carbon—but the most striking benefits are felt in farmers’ wallets, according to study from India. It found that mixed croplands interspersed with fruit trees were five times more profitable than conventional annual cropping systems.

The study took place in the semi-arid Vindhyan region of India characterized by low rainfall and generally poor soil quality, according to the study authors. They started their work on an experimental site, where they could compare seven different types of agricultural systems. Three of these were pure orchard farms of mango, guava, and Indian gooseberry; one was a teak tree plantation; and another was a traditional annual cropping farm that rotated between mung beans and wheat. Finally, two plots contained either mango or guava trees, each interspersed with two annual crops of wheat and mung beans.

Throughout the experiment the researchers took carbon measurements, tracking its presence in trees and vegetation, ground biomass, and soil.

This revealed the study’s central finding: tree-based systems were noticeably richer in carbon. When the whole system was considered—vegetation, biomass, and soil—the pure mango orchard emerged as the clear winner, managing to contain 46.63 tonnes of carbon per hectare. Meanwhile, the highest rates of carbon sequestration occurred in the guava-only orchard, which absorbed almost 8 tonnes of CO2-equivalent per hectare, per year. Conventional systems containing just annual crops had the lowest amounts of soil organic carbon, and the lowest carbon density, overall. 

When they then expanded the benefits to look at the economics of each plot, a different agricultural winner emerged. In this case, the researchers found that the mango-annual plot, where wheat and mung beans crops were interwoven with fruit trees, not only accumulated the highest amounts of biomass and had the highest carbon density in vegetation, but also produced significant financial gains. Farmers on these lands would reap net returns of over $4,800 per hectare per year. That figure is almost five times higher than they’d reap from an annual cropping system, showing potentially huge livelihood gains for farmers. 

This shows how trees can balance both environmental and economic needs in farming landscapes, the researchers say. That doesn’t mean that mixed-use agroforestry will be the answer everywhere: in fact the study shows that the benefits of tree farming are often highly distinct. The best solution could differ depending on the farming context, and what the goal is—whether to increase rates of carbon sequestration, or help farmers thrive. 

Singh et. al. “Carbon storage and economic efficiency of fruit-based systems in semi-arid region: a symbiotic approach for sustainable agriculture and climate resilience.” Carbon Research. 2024. 

Photo by Allec Gomes on Unsplash