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November 11th, 2014:

Crop yields cut by almost half due to India’s dirty air: study

04 November, 2014

The Guardian

Study finds that 90 per cent of falls in production of wheat and rice over 30 years could be attributed to black carbon and ground level ozone

Air pollution in India has become so severe that crop yields are being cut by almost half, scientists have found.

Researchers analysed yields for wheat and rice alongside pollution data, and concluded significant decreases in yield could be attributed to two air pollutants, black carbon and ground level ozone. The finding could also be relevant to farmers in China, as well as having implications for global food security as India is a major rice exporter.

Black carbon is mostly caused by rural cooking stoves, and ozone forms as a result of motor vehicle exhaust, industrial emissions, and chemical solvents reacting in the atmosphere in the presence of sunlight. Both are “short-lived climate pollutants” that exist locally for weeks to months, with ozone damaging the leaves on plants and black carbon reducing the amount of sunlight they receive.

The study looked at both the effects of climate change and the two pollutants on crop yields.

“While temperature has gone up in the last three decades, the levels of smog and pollution have changed much more dramatically,” said Jennifer Burney, an environmental scientist at the University of California, San Diego, and co-author of the paper, published in Proceedings of the National Academy of Sciences. “But this was the first time anyone looked at historical data to show these pollutants are having tremendous impacts on crops.”

Comparing crop yields in 2010 to what they would be expected to be if temperature, rainfall and pollution remained at 1980 levels, the researchers showed that yields for wheat were on average 36 per cent lower than they otherwise would have been, while rice production decreased by up to 20 per cent. In some higher population states, wheat yields were as much as 50 per cent lower.

Using modelling to account for the effects of temperature increase and precipitation changes in that time, they were able to show that 90 per cent of this loss is attributable to the impact of the two pollutants.

The results are specific to India’s seasonal patterns, the crops, and its pollution levels, but may extend to other places with similar problems. Chinese scientists warned in February that air pollution is slowing photosynthesis in plants, with effects “somewhat similar to a nuclear winter”.

Previous studies had used experimental data looking at the impact of ozone on plants to extrapolate potential losses, but this is the first study to use actual historical agricultural and emissions data to account for lower crop yields.

“Overall I think it’s a great paper,” said Stanford University agricultural ecologist David Lobell. “I think in both India and China there is growing recognition of the toll poor air quality has on agriculture. This study will certainly add to that.”

Lobell and Burney both point out that because black carbon and ozone are short-lived pollutants, they present a clear opportunity for tackling climate change. While long-lived greenhouse gases like carbon dioxide and nitrous oxides can persist in the atmosphere for decades, addressing sources of the short-lived pollutants will have more immediately perceptible effects.

Measures such as improved cooking stove technology for rural areas, or cleaner coal consumption and diesel filters on trucks in urban ones, could go a long way to improving the impact on agricultural yields.

“Our thought is that these are more politically tractable points of entry for making a meaningful change in the climate,” said Burney. “There’s a really local benefit in taking on some sort of costly action.”

670,000 deaths a year the cost of China’s reliance on coa

05 November, 2014

Li Jing

Smog caused by coal consumption killed an estimated 670,000 people in China in 2012, according to a study by researchers that tries to put a price tag on the environmental and social costs of the heavy reliance on the fuel.

Damage to the environment and health added up to 260 yuan (HK$330) for each tonne produced and used in 2012, said Teng Fei , an associate professor at Tsinghua University.

The 260 yuan is made up of two parts: the health cost and the environmental damage caused by mining and transporting coal.

“With existing environmental fees and taxes of between 30 to 50 yuan for each tonne of coal, the country’s current pricing system has largely failed to reflect the true costs,” Teng said.

Tiny particulate pollutants, especially those smaller than 2.5 micrograms (known as PM2.5), were linked to 670,000 premature deaths from four diseases – strokes, lung cancer, coronary heart disease and chronic obstructive pulmonary disease – in China in 2012, Teng said.

That translated to an external cost of 166 yuan for each tonne of coal consumed. Authorities levied only about 5 yuan as a pollution fee per tonne of coal used by consumers including power companies and iron, steel and cement producers.

Mining and transport add 94 yuan per tonne, including through damage to groundwater resources, subsidence, deaths and occupational diseases.

Beijing is considering replacing pollution charges with more stringent environmental protection taxes, but progress on legislation has been slow.

Li Guoxing , from Peking University’s School of Public Health, said the full impact of coal use was still underestimated as the study did not take into account medical costs associated with other pollution-induced diseases such as asthma.

“The health cost [of the study] is only based on the premature death figures due to the limitations of our research data,” said Li. “It could be way higher if we also include medical costs for other chronic illnesses.”

The study found that in 2012, more than 70 per cent of the population was exposed to annual PM2.5 pollution levels higher than 35 micrograms per cubic metre, the country’s benchmark for healthy air quality.

The World Health Organisation sets its PM2.5 safety limit at an annual concentration of 10mcg/cubic metre. That class of particulate was officially recognised as a human carcinogen last year by the International Agency for Research on Cancer, especially its link to lung cancer and a heightened risk of bladder cancer.

In 2012, some 157 million people in China lived in areas where the annual PM2.5 concentration was higher than 100mcg/cubic metre – 10 times the WHO’s recommendation.

A previous study published in British medical journal The Lancet said outdoor air pollution contributed to 1.2 million premature deaths in China in 2010, or 40 per cent of the global total. Former health minister Chen Zhu said this year that pollution caused 350,000 to 500,000 premature deaths a year in China.

The new study – based on research from Tsinghua and Peking universities, the China Academy of Environmental Planning and other government-backed institutes – represents the latest lobbying efforts by some Chinese experts to cap coal consumption.

But this is a difficult task, as the country relies on the fuel for nearly 70 per cent of its energy.

Teng estimates there would be a further cost of 160 yuan per tonne, on top of the 260 yuan calculated in the study, if the long-term social impact of climate change from coal burning were considered.

Zhou Fengqi , a former energy official, said it was impossible for the country to radically slash coal consumption in the coming decades.

8 ways to rethink resources: nappies to benches and food waste to biogas

3 November 2014

Conscious consumers know not to use disposable plastic bottles, or single-use plastic bags, and try to use as little packaging as possible in order to save the planet. A growing number of companies are also developing innovative ways to give waste a second lease of life.

1. Nappies to roof tiles and railway sleepers

Every parent knows that disposable nappies generate enormous amounts of waste. And with the average baby using the equivalent of 150kg of wood, nappies waste a lot of resources, too.

To remedy this, two years ago Scotland – with a total of 450,000 used nappies per day – pioneered a nappies-to-roof tiles scheme. Nappies are collected in recycling bins and sent to treatment plants, where they’re sterilised and the human waste removed. The plastics and celluloid contained in the nappies are then converted to everyday products such as park benches, railway sleepers and road signage.

In Mexico, consumer product giant P&G now turns rejected Charmin nappies into roof tiles, while scraps from its American Pampers nappies are reused as upholstery filling. Fifty P&G plants now produce zero manufacturing waste, and it claims that repurposing the waste has created an additional value of $1bn for the company. Elsewhere, a growing number of parents are turning to GNappies. The British company makes nappies in two parts: covers that can be reused, and inserts that can be composted or even flushed down the toilet with human waste.

2. Paper to reduce food waste

Rarely does one blank piece of paper make a big difference. But FreshPaper, an organic and biodegradable sheet added to fruit and vegetables, keeps the produce fresh for two-four days longer, thereby eliminating countless tonnes of wasted food. As world demand for food keeps rising, eliminating food waste will become even more important. Today FreshPaper, first sold at farmer’s markets in America, is available in shops in several dozen countries.

3. Sustainable construction materials

San Diego-based Ecor takes cellulose fibres, a material found in wood, cardboard and even forest and agricultural waste, and turns it into new construction material. The process is surprisingly simple: the waste is mixed with water, heated, pressurised and made into sturdy panels that can be used in a variety of functions: as wall panels, tables, bowls, building walls, even glasses frames. Best of all, the products contain no toxic additives and can themselves be recycled at the end of their life-span.

4. Clothes from old water bottles

If you really need to buy soft drinks or even bottled water, make sure to recycle the bottles; they can be used for yarn. Bionic Yarn turns used PET bottles into fibres that can be used in clothes. This is how it works: the bottles are cut into chips, which are in turn shred into fibres. The fibres are mixed with polyester and spun into yarn. The end product, reports Bionic Yarn, contains 40% recycled plastic bottles, including ones from the large colonies of plastic bottles floating on the world’s oceans.

5. Agri-waste into plastic bottles

Bio-on provides an excellent reason to choose your plastics carefully. The Bologna-based company has developed a pioneering process that allows it to turn agricultural waste into biodegradable plastics. Using a fermentation process involving sugar beet, Bio-on manufactures plastics that can be used for anything from food packaging to electronics. Better yet, the process requires no chemical additives, and the end products are biodegradable, dissolving upon prolonged contact with bacteria.

6. Worms as fertiliser

Repurposing waste can be as simple as it is ingenious. In Guatelamala, Byoearth uses red worms to transform food and other biodegradable waste into organic fertiliser. Doing so, of course, reduces waste but also results in higher-quality soil.

7. Food waste to biogas

Got food waste, need energy? BioTrans Nordic has got just the thing for you, especially if you work in a restaurant, canteen or other large kitchen. The Danish company’s BioTrans tank stores food waste, where it turns into biomass. The biomass is collected by a truck for delivery to biogas plants and delivery to local customers.

8. Recycling polyester

Japanese firm Teijin didn’t set out to repurpose clothe; it’s a chemical company. But, almost as a by-product of its R&D, Teijin discovered a way of recreating polyester from itself. Because reusing clothes’ fibres has long been considered near-to impossible, Teijin’s discovery was a considered a breakthrough. It has already saved tonnes of clothes from landfill, and earlier this year, Swedish firm Re:newcell unveiled a similar process for cotton. For several years now, retailer Patagonia has sold clothes made from Teijin-recycled fabric.

Today you can wear new clothes made from old clothes and old plastic bottles, while eating food enhanced by old food – and stored in plastic containers made from agricultural waste – in a restaurant powered by food-waste energy and decorated by agricultural-waste wood panels with nappy-based roof tiles. Not too shabby.

How education can change people’s attitudes about waste disposal

04 November, 2014

Edwin Lau

The Council for Sustainable Development is heading in the right direction with plans to charge according to the amount of waste each household disposes of. This will be the best incentive to drive down waste generation. However, the council and the Environment Bureau seem to worry about whether people will act properly and not dump their waste in public areas when legislation is in place.

They seem to have forgotten how effective a tool education can be – more effective than policing – in changing attitudes about social and environmental issues. Some think education takes a long time to achieve results. It really depends on the approach. Government propaganda on TV won’t work; constant public engagement and provision of convenient recycling facilities will.

Two recent success stories show how Hong Kong people can change their attitudes about the environment once they have a better understanding of the problems and the eco-friendly options available.

Case one is our four-week trial in a private residential building to educate tenants on what to do in a waste charging simulation exercise. We worked with the group Greener Action to educate tenants and set up systems to separate items for recycling before putting the remaining waste into designated bags every evening and recording their weight. Some 90 per cent of tenants took part; the amount of waste for disposal was cut by up to 30 per cent.

The second success is our food waste recycling trial in public housing. To get tenants to reduce waste seems mission impossible in the minds of senior government officials, who believe only regulations can make tenants act.

We approached the estate management to inform them of our waste crisis, and took them to visit – and smell – our landfills and food waste recycling plants, and encouraged interaction with our trained staff and volunteers to motivate them to act.

Senior officials found it amazing that, after our education processes, housewives, the elderly and young parents alike put their food waste into a small bucket, and brought it downstairs every evening to pour into a special bin for a food waste recycler to take away. In a year, around 250 tonnes were collected from over 940 households.

In Taipei city, the government organised more than 300 meetings to educate and motivate citizens to turn a once-unwelcome policy into a habit for most citizens. Such habits have helped bring down the waste disposal amount by 60 per cent since the introduction of waste charging in 2000.

Recently, an international insurance company asked whether other plastic items, besides bottles, could be put in recycling bins for plastic. The public may generally be more environmentally aware these days, but many still do not fully understand the simple steps to go green. Education can help.

Of course, we need the government to establish the green “hardware” to treat our waste to extend the life of our landfills. But what we badly need is waste charging legislation coupled with public education. That will motivate everyone to cut waste, reuse and recycle in order to pay as little as possible. Education does not require spending billions of dollars of taxpayers’ money.

The Council for Sustainable Development is due to submit its recommendations to the Environment Bureau soon, and it proposes to allow certain types of buildings to begin with a less effective scheme (charging based on the amount of waste per building) if they cannot immediately adopt the mode of waste charging per tenant. There may be a need for such arrangements but, within a year or two, the whole city should have adopted the best method to cut our waste as much as possible to tackle this crisis.