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How your family eating habits can help

 

 

 

 

Growing your own fruit and vegetables will save on your contribution to transport costs and keep you in touch with the earth; a healthy past time. Home grown vegetables are highly nutritious.

 

Meat The Challenge      

Roo poo emits no methane   

Divorce Rates & the Environment    New Zealand considers its methane contribution   

China's methane output from poultry & livestock  Belching Discovery could aid fight against global warming

The next time you throw a steak on the barbie, think about this. Agriculture produces more greenhouse gases than cars and air travel.

Eighty per cent of these gases come from the feeding, flatulence and freighting involved in putting mostly red meat on our tables. And some of the gases – methane and nitrous oxide – are more powerful global warmers than carbon dioxide.

A paper from leading researchers, including two Australians, has laid out a way forward. They hypothesise that limiting livestock production could have a rapid effect on global warming, and that using technology to reduce the gases produced won't get you there.

The answer is having radically lower meat consumption in high income countries, while bringing poor nations up to reasonable levels.

They say that just to stabilise greenhouse gas production, global meat consumption per head should be 90 grams a day.

That would reduce heart disease, obesity and bowel cancer in countries like Australia, and make poor nations much healthier through high quality protein. Converting from ruminant meat to animals with a single stomach would also help.

While the authors argue for policy changes that would bring this about, the big question is whether the temptation of meat is too great to resist.

For Reference

Title: The Lancet
Author: McMichael AJ et al. Food, livestock production, energy, climate change and health.
URL: http://www.thelancet.com/
2007;370:1253-1263

Summary

Food provides energy and nutrients, but its acquisition requires energy expenditure. In post-hunter-gatherer societies, extra-somatic energy has greatly expanded and intensified the catching, gathering, and production of food. Modern relations between energy, food, and health are very complex, raising serious, high-level policy challenges. Together with persistent widespread under-nutrition, over-nutrition (and sedentarism) is causing obesity and associated serious health consequences. Worldwide, agricultural activity, especially livestock production, accounts for about a fifth of total greenhouse-gas emissions, thus contributing to climate change and its adverse health consequences, including the threat to food yields in many regions. Particular policy attention should be paid to the health risks posed by the rapid worldwide growth in meat consumption, both by exacerbating climate change and by directly contributing to certain diseases. To prevent increased greenhouse-gas emissions from this production sector, both the average worldwide consumption level of animal products and the intensity of emissions from livestock production must be reduced. An international contraction and convergence strategy offers a feasible route to such a goal. The current global average meat consumption is 100 g per person per day, with about a ten-fold variation between high-consuming and low-consuming populations. 90 g per day is proposed as a working global target, shared more evenly, with not more than 50 g per day coming from red meat from ruminants (ie, cattle, sheep, goats, and other digastric grazers).

Roo bacteria key to cattle and sheep methane output

SYDNEY- Australian scientists are trying to give kangaroo-style stomachs to cattle and sheep in a bid to cut the emission of greenhouse gases blamed for global warming, researchers say.

Thanks to special bacteria in their stomachs, kangaroo flatulence contains no methane and scientists want to transfer that bacteria to cattle and sheep who emit large quantities of the harmful gas.

Livestock passing wind contribute  a surprisingly high percentage of total emissions in some countries.

The Examiner, Launceston , Friday December 7th p.18

Your comment- get involved in our discussion group.

Divorce Toll- Launceston Examiner (The Sunday Examiner Magazine p.11), Sunday December 9th 2007

Increasing rates of divorce around the world have a negative impact on the environment, leading to a less efficient use of energy and resources and bigger expenditure on utilities, according to a new study.

"Divorce usually causes a former spouse to move out and form a new household, thus increasing the size of materials and land for housing", a study by researchers at Michigan State University has said.

Researchers surveyed 3283 homes in the US between 2001 and 2005, and found that divorcing households registered a 61 percent increase in the number of rooms a person, compared with six percent increase in households that remained married.

" Because of higher consumption per person, an individual in a divorced household may also generate more waste ( solid, liquid, and gaseous material like greenhouse gases) that contributes to global environmental changes such as climate change and biodiversity loss" it said.

New Zealand Considers its methane contribution

In New Zealand , a country highly dependent on its pastoral based exports and  a signatory of the Kyoto protocol,   recent study ( Giles & Mosk 2005  [1]  determined that it would be more effective to achieve its international obligations to  reduce greenhouse gases by reducing the excretion levels of  the ruminant animals ( sheep, beef cattle & dairy cows),  by changing their diet and introducing  vaccination aimed at reducing the methane producing bacteriarather than reducing the levels of production of these animals by New Zealand.

They argue that altering the market share of New Zealand will ultimately lead to increased methane levels by other countries that are less advanced in the industry taking up the availability of demand on world markets. 

1."A long term environmental Kuznetz' Curve Analysis for enteric methane emission from ruminant eructation in New Zealand" - Davis E.A. Giles & Carl A Mosk - Dept. Economics, University of Victoria, Victoria, B.C., Canada - Revised Sept. 2005 .

 It should be pointed out that there is controversy  about this paper and its conclusions, and we are uncertain about its peer review and publication. webmaster

China's methane output from livestock & poultry

 In China, it is estimated that between 1949 and 2003, methane production from livestock has been rising at an annual growth rate of 2.2% from enteric fermentation and 3.5% from manure management, while nitrous oxide emissions from manure have increase annually by 3%. This gives a total annual growth rate of 2.4%. This presents a crisis and a challenge.

Estimation of methane and nitrous oxide emission from livestock and poultry in China during 1949–2003

J.B. Zhou, M.M. Jiang and G.Q. Chen

aNational Laboratory for Complex Systems and Turbulence, Department of Mechanics, Peking University, Beijing 100871, China
Received 13 November 2006;  accepted 18 January 2007.  Available online 7 March 2007.

Abstract

To investigate the greenhouse gases emission from enteric fermentation and manure management of livestock and poultry industry in China, the present study presents a systematic estimation of methane and nitrous oxide emission during 1949–2003, based on the local measurement and IPCC guidelines. As far as greenhouse gases emission is concerned among livestock swine is found to hold major position followed by goat and sheep, while among poultry chicken has the major place and is followed by duck and geese. Methane emission from enteric fermentation is estimated to have increased from 3.04 Tg in 1949 to 10.13 Tg in 2003, an averaged annual growth rate of 2.2%, and methane emission from manure management has increased from 0.16 Tg in 1949 to 1.06 Tg in 2003, an annual growth rate of 3.5%, while nitrous oxide emission from manure management has increased from 47.76 to 241.2 Gg in 2003, with an annual growth rate of 3.0%. The total greenhouse gas emission has increased from 82.01 Tg CO2 Eq. in 1949 to 309.76 Tg CO2 Eq. in 2003, an annual growth rate of 2.4%. The estimation of livestock methane and nitrous oxide emissions in China from 1949 to 2003 is shown to be consistent with a linear growth model, and the reduction of greenhouse gas emission is thus considered an urgent and arduous task for the Chinese livestock industry. Full article acquisition

 

Belching discovery could aid fight against global warming

TOKYO- Researchers have stumbled on a way to stop cows from emitting methane- a potent greenhouse gas- when they belch, in a finding that could help the fight against global warming.

Methane generated when livestock belch while eating is said to account for about 5 per cent of global greenhouse gas emissions. But supplementing the animals' diet with cysteine, a type of amino acid, and nitrate can reduce the methane they produce according to the researchers.

Methane is generated in the stomachs of ruminants, such as cows and sheep, as bacteria breaks down the plant fibres.
The gas is emitted into the atmosphere when the animals belch as they chew cud.

A research team at Ohio University of Agriculture in Hokkaido initially noticed that dairy cattle that consume a large amount of nitrate from grass growing in soil doused with high levels of chemical fertiliser release only traces of methane when they belch.

The Examiner, Launceston,Thursday January 24, 2008