Tibetan yak and sheep herder Drugtop does not know much about the science of climate change but certainty knows all about its consequences. He knows that in the coming spring his nomadic life under the wide blue skies on the grasslands fringing Zhaling Lake in central Qinghai province's Madoi county will be changed forever. Local government officials have told him he has to drastically cut his herd of 150 yak and flock of 600 sheep and leave the land that his forefathers have survived on for centuries. The action is being forced on Drugtop because he lives and grazes his animals in a special environmental protection zone within the Three Rivers Sources region of the Qinghai-Tibetan Plateau. An average of 4,000 metres above sea level, the area is dotted with valleys and snow-capped mountains and the 318,000 sq km of grasslands are the origin of the nation's most crucial waterways - the Yellow, Yangtze and Lancang rivers. Although the government's relocation message has been unofficial, Drugtop recognises the inevitability. But despite promises of subsidies and better grazing lands, he is worried. 'I don't want to go. This is our home but we know we have no choice. The move is to protect the land,' said the thirtysomething herder as his wife poured yak butter tea and his three year-old daughter played in their white maikhan, a traditional Tibetan tent. The three are dressed in traditional Tibetan robes. Outside sits the only sign of modernity - a new motorcycle used instead of a horse to move the stock. Drugtop's predicament is representative of the fate of nearly 100,000 mostly ethnic Tibetan herders who live within the Three Rivers Source region, an area that has changed drastically over the past few decades. Rainfall levels have dropped and temperatures risen, leading scientists to believe global climate change is responsible. Combined with the increasing human population and over-grazing by animals, the new weather patterns have broken the region's fragile ecological balance. In Drugtop's home county of Madoi alone, scientists have found that over the past 10 years half its 4,000 lakes have disappeared and around 70 per cent of its 1.6 million hectares of grassland have receded to become desert. Rivers are being devastated and scientists have estimated water flow in the upper reaches of the Yellow river alone has dropped 9.8 cubic metres per second a decade over the past 40 years. The deterioration poses not only an environmental crisis but also a social stability issue. The region historically provides around a half of the Yellow river and a fifth of the Yangtze river's water flow. The two rivers together are the main water source for more than 500 million people. For the area's residents, the pain is more palpable then ever. 'It used to rain 15 to 20 times a year. Now, it's only three to four times,' said Yangke, a 55 year-old Tibetan sheep herder as his 200 sheep drink from a government-built well in the Tanggarmo area. 'The grass is no longer good and there is little water,' he said as a cold wind whipped up sand from the impoverished ground. Around 400km to the south in Huashixia county, 57 year-old herder Jielu said that the dry grass no longer adequately sustained his 200 sheep. 'People don't want to buy skinny sheep. My sheep can only be sold at one-fourth of the price for fat sheep' he explained in front of his wife, nephew and four nieces as he lay on a mat inside his maikhan. Herders said a fat cow could sell for as much as 3,000 yuan while a good sheep could go for 400 yuan. Because of poor grass, the herder said his annual income had dropped from 20,000 to 3,000 yuan in the past few years. To help feed his family, the government provides a monthly subsidy of 25kg of flour. But the authorities are doing more than building wells and handing out food. With the central government set to provide 2.5 billion yuan, they will reduce the number of herders and livestock within the special Three Rivers Source protection zone. According to people familiar with the plan, the region will be divided into five management districts with 25 special environmental protection zones. Under each zone, local authorities will implement specific measures, including relocating herders to new grasslands, reducing livestock numbers to subsistence levels, plus paying cash subsidies. Interestingly, authorities are consulting herders and community groups about the details of the plan, something unheard of in past relocation schemes. Local cadres recently took Drugtop to the grasslands in nearby Golmud county to see if the area was suitable for his family. In southern Qinghai's Yushu county, the Snowland Great Rivers Environmental Protection Association assessed herders' opinions and then provided suggestions to the government. The association's Tibetan founder, Haxi Zhaxi Duojie, said the local officials, who are also mostly Tibetan, welcomed his efforts. 'Our work is to ensure that Tibetan people and culture are the foundation of any protection plan.' Despite these apparent enlightened efforts, the huge plan faces resistance. Herders are worried about losing their incomes once they move. In many cases, the promised subsidies will cover only a fraction of the losses. Drugtop, who has been promised an annual 1,600 yuan subsidy for each member of his family, currently earns around 10,000 yuan a year. Yangben, a Tibetan herder from Suzhi county who grazes his 1,000 head of sheep near Qinghai Lake, will have to cut his flock to 300 next year. While the government has promised him a subsidy, the amount has yet to be determined. 'Once we have fewer animals, we will have less money,' said the herder who still rides a horse to direct his flock. But what worries people most is the impact on the region's lifestyle and culture. 'Tibetans have lived here for thousands of years. Our traditions are based on respect and worship of nature. By taking the herders off the land, what is this going to do to our culture?' asked Haxi. To placate such fears, the government has said in eight to 10 years, herders may be allowed to return to their homelands if the land has recovered. But locals said such a prospect was not settling any nerves because the majority believed the region's conditions would only worsen. Regardless of the plight of these people, the land's worsening conditions have forced the government to act, no matter what controversies remain.