Climate change: Planet-warming power of cattle urine can be avoided by restoring farmland, study finds

Greenhouse gases from livestock can be cut by ensuring pastures are healthy, scientists say

Scientists have found restoring cattle pastures brings an unlikely environmental benefit by cutting the greenhouse gas emissions from cattle urine.

The planet-warming power of methane gas emitted by cows is well known, but their urine is also a contributor to climate change.

When the animals urinate on pastures, they produce the greenhouse gas nitrous oxide, which like methane has a far more powerful climate effect that CO2.

Previous research on the Somerset Levels in the UK has shown how adding cow urine to grassland stimulates gas production by adding nitrogen to the system and increasing soil water content.

In a new study, scientists investigated the levels of nitrous oxide coming from cow pastures across Latin America and the Caribbean after pouring samples of urine onto them.

They found that while the urine inevitably produced greenhouse gases, up to three times as much came from grassland that suffered from overgrazing and low soil quality.

With degraded land covering 150 million hectares of Latin America, this finding adds a further incentive to restore these pastures to their former quality.

“Degraded pastures are bad in so many ways,” said Dr Ngonidzashe Chirinda, a researcher at the International Centre for Tropical Agriculture and the study’s lead author.

“This study adds to the case for land restoration. Degraded pastures not only affect food security and the livelihood of farmers today, but affects the livelihood of future farmers because they emit more gases that cause global warming.”

Farm emissions are a major contributor to climate change, releasing CO2, methane and nitrous oxide that accounts for 10 per cent of emissions in the UK alone.

The new study was published in the journal Scientific Reports.