Conservation farming key to food security

Conservation agriculture can boost crop production especially for farmers who cannot access fertilisers, a new study by the International Maize and Wheat Improvement Centre now says. The system helps prevent losses of arable land while regenerating degraded lands.

The study, conducted by an international team of researchers, found out that eco-friendly practices such as growing a range of crops, including legumes such as beans or pigeon pea, and adding plant residues or manure to soils can raise food crop yields in places such as rural Africa, where small-scale farmers cannot apply adequate nitrogen fertiliser.

In their study, whose results were published in science journal Nature Sustainability, the researchers examined data from 30 long-running field experiments involving staple crops such as wheat, maize, oats, barley, sugar beet or potato in Europe and Africa.

They compared farm practices that work with nature to increase yields and explore how they interact with fertiliser.

The long-term experiments were carried out under "climate-smart" conservation agriculture practices, which include reduced or no tillage, keeping some crop residues on the soil, and growing a range of crops.

"Agriculture is a leading cause of global environmental change but is also very vulnerable to that change. We found combinations of farming methods that boost harvests while reducing synthetic fertiliser overuse and other environmentally damaging practices," observed Dr Chloe MacLaren, a plant ecologist at Rothamsted Research, UK, and lead author of the paper.

"In places where farmers' access to fertiliser is limited, such as sub-Saharan Africa..., ecological intensification can complement scarce fertiliser resources to increase crop yields, boosting households' incomes and food security," said Dr Christian Thierfelder study co-author.

They noted that to intensify production on the current arable land to feed its rising numbers, the new model must substitute human-made inputs like chemical fertilisers, to maintain or increase yields.

According to the researchers, these maize-based cropping systems showed considerable resilience against climate effects that increasingly threaten smallholders.