GREEN ADVOCATES lamented that for the 40th anniversary of Earth Day two days ago, there was one environmental problem that the world had not fully addressed yet: meat consumption.

Aside from the billion tons or so of CO2-equivalent greenhouse gases every year being added to the atmosphere, investigations and detailed analyses have shown how the global livestock sector has severely damaged the environment.

The Food and Agriculture Organization of the United Nations in 2006 made an in-depth assessment on the significant impact of the world?s livestock sector on the environment (readers can download the whole study on the Web). Aptly titled ?Livestock?s long shadow,? it cites the ?very substantial contribution of animal agriculture to climate change and air pollution, to land, soil and water degradation and to the reduction of biodiversity.?

?This is not done simply to blame the rapidly growing and intensifying global livestock sector for severely damaging the environment but to encourage decisive measures at the technical and political levels for mitigating such damage,? the assessment said.

?Hamburgerization? of forests

John Robbins, author of ?The Food Revolution: How Your Diet Can Help Save Your Life and Our World,? wrote in the chapter ?Trading Tropical Rainforests for Cheeseburgers? tropical rainforests were being destroyed at a terrifying rate. Every second, an area the size of a football field is destroyed forever, according to him.

?The No. 1 factor in (the) elimination of Latin America?s tropical rainforests is cattle grazing ... [We are seeing] the ?hamburgerization? of the forests,? Robbins quotes Normay Myers, author of ?The Primary Source: Tropical Forests and Our Future.?

Tropical rainforests are among the planet?s most precious natural resources, Robbins said. He added that these forests contain 80 percent of the world?s species of land vegetation and account for much of the global oxygen supply.

?These forests are the oldest terrestrial ecosystems on Earth and have developed extraordinary ecological richness. Half of all species on Earth live in the moist tropical rainforests. And the rainforests are home to the world?s most ancient indigenous peoples, tribes who have lived in harmony with their environment since before the time of the Pharaohs,? Robbins said.

Dr. ME Ensminger, former chair of the Department of Animal Science at Washington State University and the author of 10 books dealing with livestock raising, has this to say in his book ?Animal Science?: ?Is a quarter pound of hamburger worth a half ton of Brazil?s rainforest? Is 67 square feet of rainforest too much to pay for one hamburger? Should we form cattle pastures to produce hamburgers in the Amazon, or should we retain the rainforest and the natural environment?

?These and other similar questions are being asked too little and too late to preserve much of the great tropical rainforest of the Amazon and its environment. It took nature thousands of years to form the rainforest, but it took a mere 25 years for people to destroy much of it. And when a rainforest is gone, it?s gone forever.?

Greenhouse gases

The worldwide meat production of beef, chicken and pork emits more atmospheric greenhouse gases than do all forms of global transportation or industrial processes.

Scientific American?s Nathan Fiala wrote in the February 2009 issue that on the basis of data from the United Nations Food and Agriculture Organization and the Emission Database for Global Atmospheric Research, current levels of meat production add nearly 6.5 billion tons of CO2-equivalent greenhouse gases every year to the atmosphere: Some 18 percent of the worldwide annual production of 36 billion tons. The author adds that only energy production generates more greenhouse gases than does raising livestock for food.

Earth-shattering facts

In ?Proof Positive: How to Reliably Combat Disease and Achieve Optimal Health through Nutrition and Lifestyle,? author Dr. Neil Nedley enumerates the following:

Environmental damage from raising livestock: clearing of forests, killing meadow grass, feedlot runoff, topsoil erosion, water shortages, water pollution, increase in greenhouse gases.

?It is increasingly obvious that environmentally sustainable solutions to world hunger can only emerge as people eat more plant foods and fewer animal products. To me it is deeply moving that the same food choices that give us the best chance to eliminate world hunger are also those that take the least toll on the environment, contribute the most to our long-term health, are the safest, and are also, far and away, the most compassionate toward our fellow creatures,? Robbins said.