Targeted plan supports soil potassium management

Experts suggest steps to address potassium deficiency challenges, increase food security and support sustainable agriculture.

Potassium in soils is essential for crop production, but a current lack of the key nutrient in soils worldwide could have potential consequences for global food production

Potassium deficiency can cause lower crop yields, and addressing this issue is crucial to producing enough food to feed a growing population, researchers suggest.

Experts, including researchers from the Global Academy of Agriculture and Food Systems, outline six key actions that can safeguard food production and promote sustainable agricultural practices.

Deficiency challenge

Around 20 per cent of agricultural soils worldwide face potassium deficiency, with regions such as Southeast Asia, Latin America, and sub-Saharan Africa particularly affected.

While nitrogen and phosphorus sustainability issues are widely known, potassium remains in the shadows.
Dr Peter Alexander, Senior Lecturer in Global Food Security

Most of the world's natural potassium reserves are mined in Canada, Belarus, and Russia, leaving many countries vulnerable to supply disruptions, as they rely on imports.

Environmental impact

Potash mining, the main method for potassium extraction, leaves a considerable environmental footprint in the form of salt left over from the mining process.

Without proper management, this salt can harm ecosystems when washed into rivers and groundwaters.

Key actions

To address soil potassium deficiencies and guard against price volatility and environmental impacts, experts propose a set of measures.

Currently, there is no system in place to assess global potassium soil stocks. A quantified life-cycle analysis of potassium could pinpoint opportunities to reduce losses, scientists recommend.

This analysis could also identify regions where potassium recycling strategies, for example adding leftover potassium from animal waste back into the soil, could be enhanced.

Despite the volatility of potash prices, there is no current system to forecast price changes. Experts advocate for enhanced potassium supply and demand monitoring, to safeguard farmers and mitigate food security risks.

Ecosystem effects

The environmental impact of potash mining is not well understood. A combination of laboratory and field studies could establish safe potassium concentrations for aquatic life and help researchers better understand the implications of potash pollution on ecosystem integrity.

Local studies could support farmers in maintaining healthy potassium levels in their soil, by establishing targeted fertiliser recommendations dependent on the type of crops being planted, and existing levels of potassium in soil.

Global surveillance

International working groups which monitor nutrient availability have not yet focused on potassium management. Earlier this year, the United Nations Environment Programme (UNEP) Working Group on Nitrogen together with the Global Partnership on Nutrient Management delivered a phosphorus sustainability update to the UN, raising the opportunity for international collaborations. Similar UN momentum on potassium would increase awareness on the need for action, experts advise.

The proposed actions provide a roadmap to ensuring potassium availability does not harm food security. As the research suggests, local and international frameworks to consolidate knowledge on potassium cycles, set globally agreed targets and quantify the environmental and production benefits of action seems to be essential to paving the way for unified global action and integrated nutrient management.
Dr Peter Alexander

This blog is adapted from a perspective piece published in Nature Food in collaboration with the UK Centre for Ecology and Hydrology and colleagues from England and Spain.