Source:Xinhua Published: 2014-9-2 9:41:29
Healthier diets are not only important to ensure food security and people's health, but also to avoid dangerous climate change, according to a new British study published in the scientific journal Nature Climate Change.
The study by Cambridge and Aberdeen universities revealed that if current trends continue, food production alone will reach, if not exceed, the global targets for total greenhouse gas (GHG) emissions in 2050.
As populations rise and global tastes shift towards meat-heavy "Western diets," increasing agricultural yields will not meet projected food demands, making it necessary to bring more land into cultivation, according to the authors.
As a result, deforestation will increase carbon emissions as well as biodiversity loss, and increased livestock production will raise methane levels. They argue that current food demand trends must change through reducing waste and encouraging balanced diets.
Researchers said if we maintain "business as usual," by 2050, cropland will have expanded by 42 percent and fertilizer use increased sharply by 45 percent over 2009 levels. A further tenth of the world's pristine tropical forests would disappear over the next 35 years.
The study shows that increased deforestation, fertilizer use and livestock methane emissions are likely to cause GHG from food production to increase by almost 80 percent.
This will put emissions from food production alone roughly equal to the target greenhouse gas emissions in 2050 for the entire global economy.
"There are basic laws of biophysics that we cannot evade," lead researcher Bojana Bajzelj from Cambridge University said.
"The average efficiency of livestock converting plant feed to meat is less than 3 percent, and as we eat more meat, more arable cultivation is turned over to producing feedstock for animals that provide meat for humans."
"Agricultural practices are not necessarily at fault here, but our choice of food is," Bajzelj continued. "Food production is a main driver of biodiversity loss and a large contributor to climate change and pollution, so our food choices matter."