UWA study finds partial shift to organic inputs can reduce synthetic nitrogen use without yield loss

A field study led by the University of Western Australia found that replacing part of synthetic nitrogen fertilizer with low rates of organic inputs can sustain crop yields while improving soil quality and nutrient efficiency. The research, published in Land Degradation & Development, examined a winter wheat–summer maize rotation over two years under varying nitrogen application rates and organic fertilizer additions.

Researchers reported that reducing synthetic nitrogen fertilizer by up to 45% and partially substituting it with organic inputs improved soil quality, crop productivity, nitrogen uptake, and nutrient cycling without increasing nitrous oxide emissions. The study found that low rates of organic amendments delivered better outcomes than higher additions, supporting more efficient nitrogen use while maintaining agricultural productivity.

Kadambot Siddique, director of the UWA Institute of Agriculture, said reducing synthetic nitrogen by less than 45% alongside organic fertilizers can “maintain productivity without increasing emissions.” The findings come as fertilizer markets face continued volatility, with approximately 60% of global urea trade moving through the Strait of Hormuz, making supplies vulnerable to geopolitical disruptions and price swings. Researchers said optimizing the balance between organic and synthetic nitrogen could help lower agricultural emissions while strengthening resilience against rising input costs.

Source: Phys.org

What to know about the UWA nitrogen-reduction study