China's transformation from agricultural backwater to booming industrial powerhouse has required it to consume resources at a speed and scale the world has never seen, a new UN study has found. The report by the Kenya-based United Nations Environment Programme (UNEP) warned that the country's rapid economic development had come at a huge price - fast-depleting resources and a massive degradation of the environment. "China's dramatic economic growth over the past few decades has increased demands for natural resources within and beyond the country itself in ways that are unprecedented in human history," UN Undersecretary General Achim Steiner said in the report. "While that growth has lifted millions out of poverty, it has also come with rising environmental challenges." The report credited China's "exceptionally good" efforts at improving resource efficiency, But it cautioned that the pace of this improvement was insufficient to offset the environmental damage from extracting, processing and consuming natural resources. Analysts said the report could raise concerns about the potential for further ecological degradation as President Xi Jinping and Premier Li Keqiang pin much of their economic hopes for the next decade on a new round of urbanisation. In the last three decades, China has grown from a modest user of minerals, fossil fuels and other primary materials to become the world's largest consumer, the report found. The country consumed 22.6 billion tonnes of such materials in 2008 - nearly a third of the world's total - up from 1.7 billion tonnes in 1970. It consumes four times as much as the United States, the second-biggest user. "This is a combined result of China's huge population and fast economic growth during the period," said Chen Shaofeng , a researcher with the Chinese Academy of Sciences' Institute of Policy and Management, a main author of the report. The country's population grew to 1.3 billion from 816 million over the 38-year period. But the amount of resources used by every citizen has also soared as their living standards improved. Per capita resource consumption rose from 31 per cent of the world average in 1970 to 1.62 times the world average in 2008, with the sharpest rise coming after 2000. The report did not compare China's development with the industrialisation and urbanisation of the United States and Europe, which were stretched out over two centuries. But such developed countries have now outsourced most of their material and energy-intensive production processes to the developing world, allowing China to maintain a relatively high level of self-sufficiency. Despite a continuous increase in resource efficiency - growing at a rate of 3.91 per cent annually - the country still lags behind global and regional standards. In 2009, China used 2.5 times more energy than the global average to produce each unit of economic growth. The report also mentioned the country's environmental decline. By the end of last year, fewer than one in four major cities in China had safe air. About 30 per cent of the country's major rivers and 60 per cent of its groundwater was polluted, according to the Ministry of Environmental Protection. "Unprecedented innovation is required in the country's future development to avert further degradation," Chen said. Besides creating environmental challenges domestically, China's enormous demand for natural resources also became a driving force of the consumption rise regionally and globally, the report said. The findings come as China prepares to enact significant changes in the way it consumes natural resources, as the central government plans to move another 390 million people from the countryside to cities by 2030. Wu Changhua , the regional director for The Climate Group, said that Beijing realises that the old model of urbanisation is no longer sustainable.