Chinese mountain town

China bulldozes mountains to make way for cities

China's campaign to bulldoze mountains and create land for new cities is ambitious, even admirable, but now the world is worried.

Earlier this year, a group of hydrogeologists from China warned that their nation's campaign to decapitate mountains to create flat land and build cities could prove catastrophic.

Writing in Nature, Professor Peiyue Li from Chang'an University described countless environmental problems – air and water pollution, soil erosion, flooding – and urged Chinese government to seek home-grown and international scientific advice, and proceed with caution.

The media frenzy that followed flagged up the risks and dangers of China's ambitious urbanisation plans to the world, and now Prof Li eagerly awaits the fallout from his publication. As he tells E&T: "Following the paper, the [local government] Shaanxi Department of Science and Technology organised a meeting to bring together nationwide researchers to discuss land creation. This was a good start, but still no foreign scientists were invited."

So what exactly is the problem? If all goes to plan, in just eight years the Chinese government will have transformed a remote, largely peasant-populated, mountain region into an industrial hub housing half a million citizens.

Come 2020, Lanzhou Xinqu, or Lanzhou New Area, is expected to generate some 100 billion yuan – €12bn – in GDP. And this is just one – albeit the biggest – of five development projects to haul backward, rural hinterlands into an urban 21st century.

During the last decade, the government has been shearing the tops off mountains and filling the valleys in-between to create a plateau on which to build as part of its 'Go West' strategy. In Lanzhou, as well as Chongqing, Shiyan, Yichan and Yan'an, tens of square kilometres of land have already been created by mountain levelling and much more is to follow.

When finished, the Yan'an project will create 78.5 square kilometres of flat ground, doubling the area of the existing city while Lanzhou's planned area exceeds 300 square kilometres.

However, Prof Li warns: "These projects need more scientific guidance as important environmental and engineering risks exist."

A first for urban construction

As he points out, Yan'an is the largest project ever attempted on 'loess', thick but soft million-year-old deposits of wind-blown silt that can subside when soft. And while mountaintop removal in the form of strip mining has taken place in the US, the scale of activity in China is unprecedented.

Land creation aside, such massive areas of infill have never been used for urban construction, which also raises concern. As Prof Li highlights, the infill's ground base will need at least a decade to stabilise before construction can take place, and safe city construction is still not guaranteed. Yet vast sums of public money, along with private investment, are being relentlessly ploughed into the projects.

"Benefits to local and national residents are economic, environmental and social, but if we don't see big benefits the projects will be meaningless," he says. "Problems are not always apparent in the very short-term but they might become serious after a longer period, especially if the environmental and ecological [impacts] of land creations are not well considered."

Landslide hotspot

Over in the UK, Durham University researcher and co-director of the Institute of Hazard, Risk and Resilience, Professor David Petley, is avidly following developments in China. He says that such massive land movements can lead to landslides and, alarmingly, China has its fair share of these disasters.

In August 2008, a landslide toppled the waste dump of a local iron mine and buried Sigou Village in the northern Shanxi Province. There were 44 reported deaths. One month later, a mudslide at the Tashan Mine in the same province hit a warehouse killing 277 people and injuring dozens more.

On 29 March 2013, a massive landslide buried a mining camp belonging to Tibet Huatailong Mining Development, a wholly-owned subsidiary of China Gold International Resources, killing 83 people. Shortly afterwards, China-based researchers detected a massive landslide forming on the flanks of a reservoir close to the Laxiwa Dam in Qinghai Province, north-west China; possible damage, they said, could be "devastating".

This list, though not exhaustive, highlights a nation with an extraordinary history of landslides associated with mining and hydroelectric power generation. And worryingly, Prof Petley questions whether or not the nation has sufficient skill to prevent such accidents in its large-scale projects.

China poses a very challenging environment for landslides given its combination of steep slopes, high levels of seasonal rainfall and intense seismicity. For Lanzhou, Yan'an and other projects, Prof Petley believes flowslides – rapid and very destructive flows of loose materials typically triggered by an earthquake or rainfall – are a very real risk.

"The danger here is that the potential for flowslides from the materials blasted and then dumped as fill must be high, especially in areas that have high seasonal rainfall and/or earthquakes," he says. "Slicing off the top of a mountain also creates a large surface for water infiltration. This could drive up groundwater, also increasing the potential for instabilities.

"These landslides are not inevitable and can be avoided with a very good understanding of what can happen and good engineering," Prof Petley advises. "But unfortunately, one's confidence in China is not high."

He recommends detailed analysis of the materials, geology and hydrogeology of the slopes. "There needs to be ongoing monitoring of these as well as the behaviour of the emplaced fills," he says.

Yet this is, of course, the crux of the problem. For such an ambitious plan of massive national development – Prof Petley reckons the size of land movement is unprecedented in a mountain chain – the Chinese government seems to be proceeding at a spectacularly rapid rate without the necessary scientific and engineering guidance.

According to Prof Li some research has taken place, but this appears to be too little, too late. "The Department of Science and Technology of Shaanxi and the Ministry of China have granted 30 million yuan [€3.5m] to local research teams to conduct relevant research on land creation," he says. "The engineering project of Yan'an started in April 2012 but the research started in July 2012, so the research lags the engineering."

What's more, Prof Li believes that government research funds to date have only been attributed to the Yan'an project. "The cities are located in different regions of mainland China so engineering, hydrogeological and environmental conditions and resident density varies from city to city," he says. "Each project needs scientific guidance but, to my knowledge, the project in Yan'an is the only one funded by local and national government."

Earth impacts

Research aside, surely China's environmental regulations should at least steer development? According to Prof Li, guidelines do not exist for land creation in complex geological regions to mountainous zones and, even worse, many projects are ignoring existing regulations.

For example, in April 2013 air pollution brought work on the Lanzhou project to a grinding halt. Yet only four weeks later, and despite incomplete assessments, construction resumed due to mounting costs to government and contractors.

Prof Li is under no illusion that these projects will not be stopped, despite growing environmental concern. Given this, he believes the government's cosy assumption that such land creation will bring economic prosperity should be tested. As he says, the need to wait for infill land to stabilise indicates a long payback time for investors; economic research and cost models would quantify this.

However, while Prof Li and fellow researchers start to assess the risks of such mammoth land-moving exercises on Chinese residents and their local landscape, the developments are prompting some researchers to speak out about the bigger picture.

Dr Jan Zalasiewicz, a senior lecturer in paleobiology at the University of Leicester, UK, believes China's new cities, as well as other, similar projects such as Palm Island in Dubai, are having a massive impact on the Earth's entire geology.

"The re-engineered landscapes reported from China and Canada's Athabasca tar sands involve large-scale, multi-million tonne rock and soil transfer from one place to another," he says. "A recent 'back of a beermat' calculation showed that about 500 billion tonnes of concrete have been made on Earth, which is about one kilo of concrete per square metre of the Earth's surface, both land and sea."

Dr Zalasiewicz points out that about half of this concrete has been made in the last 20 years, and the changes don't stop here.

"We have converted about 40 per cent of the land surface to agriculture and modified more than 90 per cent of our continental shelves via trawling," he says. "As these thing happen, you get changes in the water cycle, the landscape, soils, associated chemical changes and so on. With these dynastic changes we are creating a new geology."

World-changing developments

Given the drastic rate of change, concerns over the global impact of the world's significant developments are rising with some researchers calling for 'planetary stewardship', the international global-scale management of the Earth's entire biological, chemical and physical processes. But surely, as the worrying story of China's development unfolds, the notion of worldwide cooperation on any large-scale development is, at least for now, ludicrous?

Dr Zalasiewicz maintains his field-of-expertise is grounded in interpreting the impact of human activity. "I try to deal with the facts on the ground into geology, but I certainly have colleagues who say we are now the dominant force on Earth so we'd better make a good job of it," he says. "My own suspicion is that, as ever in history when you get these large scale changes, there will be winners and losers."

But still Prof Li is hopeful that at least in his nation, a combined effort from researchers around the world will make a difference. In Nature, he states that scientists from the US Geological Survey, the US Environmental Protection Agency, the International Association of Hydrogeologists and universities in Canada, the US and across Europe should now be brought in. And as he tells E&T: "Scientists that have similar experience in similar land creation, especially those in the US with strip-mining experience, should be invited to join.

"We are inviting two US scientists to China this summer," he adds. "I hope they will give us suggestions on this project." 

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