November 12, 2009
How can livestock respiration contribute to global warming — a key conclusion of the recent WorldWatch article on livestock and global warming?
It’s confusing because we’ve learned that in a "natural state," carbon dioxide breathed out by animals is balanced by carbon dioxide taken up by plants. There is no net effect on greenhouse gas emissions from respiration by livestock, and everything is in balance, right?
To see the fallacy here, let’s back up to the time before you add that cow to the landscape. There are wild animals and humans breathing CO2, but also a lot of plants taking it up, so you have a balance. Then, along comes the cow — and boom, there goes your balance. With livestock agriculture we have bred so many animals that we have upset this natural balance. We have too many animals and not enough plants.
Many people will find this hard to believe. Don't the livestock just replace wild animals, who also breathe out CO2? And if we had too many animals, wouldn’t plants be eaten and start to disappear?
We haven’t just "replaced" wildlife with livestock during the last 10,000 years. If wild animals were sufficient to support human meat-eating, we’d still be hunting and gathering — but the last time we were hunting and gathering, our population was 1/1000 of what it is today. Humans, their livestock, and their pets are now 98% of the biomass of all land-based vertebrate species.
And in fact, plants are disappearing, even with the massive help of artificial fertilizers. Forests are being converted to grassland, grassland is being converted to desert, and cropland soil erosion is about 10 to 20 times the natural rate of soil formation.
This is all prima facie evidence for a serious and growing imbalance between animals and plants, and thus for livestock respiration contributing to greenhouse gas emissions.
In fact, what is really strange is that this whole imbalance is coming to light through a global warming analysis. If we are depleting plant life and soil, we're depleting the basis of all human life. Isn't this, like, news? It should be, but we're too distracted. No one notices that the basis of all human and animal life is being eroded; but we do notice that things are getting a bit warmer.