A team international agricultural scientists has given a warning saying the use of nitrogen fertilizer by farmers across usually evaporates to atmosphere causing gas emission a factor in climate change challenge.

In a study conducted by scientists from International Maize and Wheat Improvement Center (CYMMYT), the scientists confirmed that nitrous oxide emissions is possible after farmers have applied it their fields to boost crop yields though this can reduced  using the 4Rs strategy.

In a press release by the scientists on April 9, 2021, it is stated “an international team of scientists has strengthened our understanding of how better fertilizer management could help minimize nitrous oxide emissions while still achieving high crop yields.”

The scientists highlighted their findings in a new publication titled “Metro analysis of yield and nitrous oxide outcomes for nitrogen management in agriculture”

The publication is as a result of a collaborative effort from the International Maize and Wheat Improvement Center the University of Hawai, the Environmental Defense Fund, Plant Nutrition Canada and the Africa Plant Nutrition Institute with funding from the CGIAR Research Program on Climate Change, Agriculture and Food Security.

Research content and Nitrogen fertilizer management

This research was conducted through a meta-analysis, where the results of multiple scientific studies were statistically combined.

According to the researchers in order to meet the world’s growing demand for food, farmers need fertile soil.

Nitrogen is an essential element in plant fertilizer and can have extremely harmful effects on the environment if not managed effectively.

Numerous studies have confirmed that improving nitrogen use in agriculture is key to securing a food secure future and environmental sustainability.

“Farmers needs nuanced strategies based upon tailored nutrient management approaches that keep nitrogen balances within safe limits,” said Tai M Maaz, researcher at University of Hawaii at Manoa and lead author of the study.

Maaz notes that when farmers apply nitrogen fertilizer to their crop, typically only 30-40% of it is taken up by the plant and the rest is lost in the environment.

One of the byproduct is nitrous oxide, the most potent greenhouse gases which usually escapes in the atmosphere.

Global agriculture is a major contributor of greenhouse gas emissions, especially those derived from nitrous oxide emissions.

Although farmers are now commonly told to practice fertilizer rate reduction, or simply advised to apply less fertilizer, there are cases where that strategy is either not possible or not advisable because some nitrous will still escape to the atmosphere.

Alternative forecasters of emissions

The study found that output indicators such as partial nitrogen balance, an indicator for the amount of nitrogen prone to loss and partial factor productivity, a measure of input use efficiency, predicted nitrous oxide emissions as well as or better than the application rate alone.

This means that in some cases, where nitrogen rate reduction is not possible, nitrous oxide emission can still be reduced by increasing yield through implementation of improved fertilizer management practices, such as the use of “4Rs:” at the right source, right timing, right placement and right application rate.

Tek B Sapkota, climate scientist at the CIMMYT and co-author of the study, emphasized that it is important for farmers to reduce the rate of fertilizer use in the cropping systems where the current level of nitrogen application is excessively high.

But, when comparing the systems at the same nitrogen application rates, nitrous oxide emission can be reduced by increasing yield.

“The 4R nutrient management practices must be tailored to specific regions to help close yield gaps and maintain environmental sustainability as the win-win scenario.

The future will require public and private institutions working together to disseminate such nutrient management information for specific cropping systems in specific geographical regions,” said Sapkota, who is also a review editor of the Intergovernmental Panel on Climate Change (IPCC) sixth assessment report.