Climate change scientists found have a new worry to keep us awake at night …
January 29, 2019
International Center for Tropical Agriculture – The exceptional climate-altering capabilities of cattle are mainly due to methane, which they blast into the atmosphere during their daily digestive routine.
Cattle urine is a lesser-known climate offender.
It produces nitrous oxide (N2O), which has warming power far greater than that of carbon dioxide (CO2), the main driver of global warming.
A study conducted by the International Center for Tropical Agriculture (CIAT) and partners shows that these N2O emissions can be significantly curbed by healthy cattle pastures.
For the study, researchers collected urine from cattle at research sites in five countries across Latin America and the Caribbean.
They spilled these 500 mL samples on paired cattle fields classified as degraded or healthy, which was determined by vegetation coverage.
In six of the seven test sites, degraded pastures emitted significantly more N2O — sometimes up to three times as much.
The results were published January 29 in Scientific Reports, an open-access journal by the publishers of Nature.
“Degraded pastures are bad in so many ways,” said Ngonidzashe Chirinda, a CIAT researcher 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.”
The results add urgency to global land restoration agreements, including Initiative 20×20, which aims to bring into restoration 20 million hectares of land into restoration in Latin America by 2020 as a first major step toward even more ambitious restoration targets.
Estimates vary, but Chirinda calculates, conservatively, that there are 150 million hectares of degraded lands in Latin America. Brazil alone is home to some 80 million hectares of degraded pastureland.
Degraded livestock land is generally characterized by overgrazing, soil compaction, loss of organic material and low levels of nutrients and soil carbon.
Large-scale land restoration with improved forage grasses, rotational grazing and the addition of shrubs and trees (silvopastoral farming) could significantly mitigate the negative climate effects wrought by degradation.
In addition to reducing N2O emissions, restored landscapes generally contain more carbon, have healthier soils and more robust and productive livestock … Read more.