It has a dangerous mix of poor sanitation, high population density and limited health services.

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High population density, a poor ratio of available water to demand, and regional imbalances in available water supplies are serious challenges for China in managing its usable water supply.

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The risk of loss of lives and economic disaster in the southern Mediterranean is high due to strong population density along its coasts: around 150 million people concentrated in 46, 000 kms of coastline, 110 million of them living in cities bordering the sea and some 200 million tourists visiting the area every year.

UNESCO: Indigenous Peoples

An example of a better approach might be to group retail sites by high, medium and low population density in the surrounding 10 mile area.

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In the course of millennia of Chinese governance, they have gained almost no experience whatsoever with low population density, high-trust societies, institutions free of corruption, or a relationship of transparency between the state and those it governs.

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"It would be most useful for countries where they don't have much rain gauge data or weather radar - in Africa for instance, they do have mobile phones, at least in areas where the population density is high enough, " he told BBC News.

BBC: Rain tracked with mobile network