Scientists uncover hidden phosphorus reservoir vital for future food production

Researchers have developed a simpler and more cost-effective method to measure a biologically important form of phosphorus in soils, providing new insights into nutrient cycling that could help improve sustainable agricultural management.

Phosphorus is an essential nutrient for plant growth and global food production, yet its natural reserves are finite. Understanding how phosphorus is stored, transformed, and made available in soils is critical for maintaining soil fertility while reducing environmental impacts.

In a study published in the Journal of Agricultural and Marine Sciences, an international research team, including scientists from Sultan Qaboos University, James Hutton Institute, the Environment Authority of Oman and others, optimized a laboratory method for measuring DNA-bound phosphorus (DNA-P) in soils. DNA-P is part of the organic phosphorus pool associated with living microorganisms and plays an important role in nutrient cycling.

The researchers evaluated and modified an existing analytical protocol and applied the improved method to 32 different soil types across the United Kingdom. The revised procedure proved to be simpler, more economical, and capable of maintaining analytical precision and sensitivity.

The study showed that enzyme treatments previously used in the method were unnecessary, reducing complexity and costs. However, an ultrafiltration step remained essential to accurately separate DNA-bound phosphorus from other phosphorus-containing compounds.

Although DNA-P represented only a small fraction of total organic phosphorus in soils, its concentrations were strongly linked to soil pH, microbial biomass phosphorus, organic matter content, and phosphorus dissolved in soil water. These relationships suggest that DNA-P is closely associated with living soil microorganisms rather than long-term stable phosphorus reserves.

The findings provide researchers with an improved tool for studying biologically active phosphorus in soils and offer new opportunities to better understand how microbial communities contribute to nutrient availability for plants.

As global agriculture faces increasing pressure to use phosphorus resources more efficiently, the new method could support future research on soil fertility, nutrient management, and sustainable food production systems.