Growing more food with a reduced carbon footprint

The University of Western Australia’s Institute of Agriculture has collaborated with international researchers to identify how smallholder farms can grow more food with a reduced carbon footprint.

The study was published today in the prestigious journal Proceedings of the National Academy of Sciences of the United States of America.

The world has been struggling to find sustainable ways to produce more food for an ever-increasing human population with fewer negative environmental impacts.

The challenge is magnified in countries or regions where the availability of farmable land for agriculture is limited.

About 83 per cent of the global agricultural population (more than 2.3 billion people) rely on smallholder family farms for their livelihood.

An added challenge for agriculture is the uncertainty of the consequences of climate change and unpredictable abiotic stresses, which put pressure on agriculture to produce affordable food in sufficient quantities with minimal negative impact on the environment.

In developing countries, the lack of resources and available farmable land for agriculture has meant that many people are undernourished due to the lack of sufficient food.

In more developed countries, the excessive use of synthetic fertilisers and other agro-chemicals has negatively impacted the environment.

In China for example, excessive use of synthetic nitrogen fertilisers has increased greenhouse gas emissions, lowered nutrient-use efficiencies, and increased the risk of soil acidification and water and soil pollution.

Through 16 field experiments conducted over 12 consecutive years, the researchers found that smallholder farmers could achieve the dual goal of growing more food and lowering the environmental footprint by adopting integrated farming systems.

The research team developed an integrated cropping system that incorporated four components for farmers to follow: intensified cropping systems, relay planting within-field strip rotation, soil mulching with available means, and no-till or reduced tillage.

Co-author and The UWA Institute of Agriculture Director Professor Kadambot Siddique said adopting the ‘system integration’ model would have an immediate and significant impact on the global agricultural sector.

“Our research shows that system integration generates significant synergies,” Professor Siddique said.

“When compared with traditional monoculture cropping, it increases annual crop yields by 15.6 to 49.9 per cent and farm net returns by 39.2 per cent. Crucially, our integrated cropping system decreases the environmental footprint by 17.3 per cent.”

Professor Kadambot Siddique

Professor Siddique said the ‘system integration’ model could help alleviate challenges of global food insecurity.

“Food security has been a major concern worldwide and is a significant issue for the livelihood of rural communities in highly populated regions and countries,” he said.

“Our model is an effective way to increase crop yields and net farm income, while concurrently reducing the emission footprint per farm product.”

The approach could also be applied to many other smallholder systems worldwide, including high and low-input farming.

“However, a cross-globe approach may be required to test whether our integrated system performs similarly in other regions of the world,” Professor Siddique said.