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Smoky Home: Cleaning Up Indoor Air with Human Waste

The secret weapon in the fight against indoor air pollution—and deforestation—in China might be decomposing human waste

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MORE AND LESS:

Liming middle schoolers get that message through the Student Earth Helpers program. This poem, written as part of that program, translates:
"If more smoke in the sky, birds will be less
If more boats in the sea, fish will be less
If more people in the mountains, animals will be less
If more cars in the forest, trees will be less."
On the bright side, the poet might have added: if more biogas in the village, deforestation--and a whole host of related environmental issues--will be less.....[ More ]

SIGN OF THE TIMES:

"We believe it is very important to leave something for future generations," Cun says. "But, sometimes, to survive, [people] use it," speaking of the vestiges of once abundant timber.....[ More ]

BIOGAS BOONDOGGLE?

Despite decades of effort, most recently by environmentalist Cun (Angela) Yangfang pictured here, biogas stoves have not become ubiquitous in China.....[ More ]

OUTFOXING WASTE:

To supplement incomes and the amount of waste in such biogas systems, the villagers of Shijialing have also begun tending extra animals, such as these foxes raised for their pelts.....[ More ]

WASTE FULL BURN:

Such methane can then be piped to household burners, such as the one being demonstrated here by Shijialing village leader Shi Tongkang in Shandong Province.....[ More ]

WASTE TO FUEL:

Concrete pits, such as the one being installed in Liming by middle school principal Dong Fang, are used to store human waste, allowing it to be digested by microbes and turned into methane or, as the Chinese call it, marsh gas.....[ More ]

SUPERIOR STOVE:

Better designed wood-burning stoves, such as the one pictured here, can halve wood burning. Having such a stove has also meant less work for Feng Yu's parents.....[ More ]

SMOKE INSIDE:

Old stoves such as the one pictured here burn wood inefficiently as well as contributing to indoor air pollution at least 16 times higher than U.S. or World Health Organization standards.....[ More ]

PORK PRODUCT:

The Chinese farmer's tendency to cook fodder for pigs also contributes to an ever-expanding demand for firewood.....[ More ]

LAND RUSH:

A booming population has also driven farmers into formerly natural areas. "We farm anywhere we can farm," notes Cun (Angela) Yanfang, a Chinese environmentalist working for the Nature Conservancy and RARE.....[ More ]

WOOD WOES:

A combination of logging and rising demand for fuel wood has leveled forests throughout China, such as the one that used to cover this hillside overlooking the town of Liming in Yunnan Province.....[ More ]

WOOD WORK:

Chinese demand for wood--for everything from construction to fuel--is driving deforestation and follow-on floods both within China and abroad, in countries such as Indonesia.....[ More ]

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