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Searching for the source

The upper reaches of the Yangtze, Asia's longest river, are a scene of great environmental degradation. Yang Jibin spoke to a scientist who has recently surveyed the fragile region.

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High up where the Yangtze River rises on the Tibetan Plateau, the environment is “shocking,” said Xin Yuanhong, director of an environmental and geological survey of the area. The study, which took place from June 2005 to October 2008, found the area has been particularly affected by global warming; glaciers are receding, the permafrost is melting, the vegetation is dying off, the wetlandsa are drying up and water resources are disappearing.

The Tuotuo, Chuma'er and Dangqu rivers are known as the “three sources of the Yangtze River.” In 1978, a survey team reached the source of the Dangqu River, a stream on the side of Mount Xiasheriaba, which they identified as the source of the Yangtze River.

Xin went looking for that source in September 2006, but failed to find it. The receding glaciers meant that the source had disappeared. “Glaciers are known as solid reservoirs for rivers on the plateau,” Xin said. “Once the glaciers disappear once-permanent rivers will become seasonal or even dry up completely.”

Glacial retreat is common in the region. The glacier on the south side of Yuzhufeng, in the
Kunlun Mountains, retreated 1,500 metres between 1971 and 2005. The edges of the glacier on the east side of the Tanggula pass have moved by 125 metres, with the tip of the glacier receding 265 metres. 

Xin said there were lessons to be drawn from the fate of the Yellow River. He was part of a government study of the Yellow River source in 2000. “In 1969 there were glaciers there,” he said. “But in 2000 we couldn’t find a single one.”

Ecological catastrophes that once occurred at the source of the Yellow River are now being repeated at the head of the Yangtze River. In May 2007, Xin met a herder near the wetlands around Zhiduo and Qumalai, who was moving to live with his relatives. The grass his livestock had depended on was no longer growing; it had been replaced with a different species that neither cows nor sheep would touch, but that could survive the falling water tables. His team found that 98 of the 108 wells in the county of Qumalai had dried up in recent years. Half of the 4,077 lakes in Maduo had disappeared, and water levels in the others had dropped by two to three metres.
 

Changes in the permafrost, or frozen soil, were partly to blame. “Permafrost actually acts as a layer of waterproofing,” said Xin. “Experts say that it protects wetlands. As the permafrost thins, more surface water is absorbed – and if the permafrost disappears, the surface may dry out and become desert.” 

The survey found patches of permafrost damage on the north and south edges of the plateau. In some areas it had completely disappeared. “Vegetation protects the permafrost like a blanket. And the permafrost retains surface water, which allows the vegetation to grow.” Xin drew a circular diagram to describe the relationship. “It’s a closed, fragile chain,” he said. In many locations, he has seen irreparable damage to its links.  

In 2005, a road was built between Zhiduo and Suojia. A drainage channel was dug alongside the road, which exposed the permafrost to the elements. A year later it had melted and collapsed. Xin saw that the permafrost was still melting there in 2007. The road had to be re-routed – and then re-routed again after the same problem struck – causing great difficulty and financial loss. Road building over permafrost is a problem across the world. The Qinghai-Tibet highway, despite reconstruction and repair work, is at risk from the irreversible damage being done to the permafrost by global warming and a lack of understanding in the road's initial construction.

The survey found many problems caused by human damage to the permafrost, including road building around the Chuma'er River plateau, the Wudaoliang basin, the Xiushui and Beilu rivers and the Tuotuo River basin. “When a road cuts through wetlands they get divided in two, cutting off the water supply for the downstream section, “ explained Xin. “Damage to the permafrost, caused by the building of the Qinghai-Tibet highway and railway – and the houses alongside them – has resulted in subsidence and can cause landslides.” The sides of the highway were the first area to be covered in the survey, since they are easy to reach. In many of these areas, subsidence has left buildings at risk of collapse.  

Wetlands – the “kidneys of the world” -- are a unique and resource-rich ecosystem. They absorb flood waters, moderate the climate and cleanse the environment. Xin said the degradation of the wetlands could lead to environmental disaster. The county seat of Qumalai has been moved twice due to a lack of water in the Tongtian River, a tributary of the Yangtze River. Even there at the head of the river, there is no water. Many wetland areas on the Dangqu River (which means “marsh river” in Tibetan) had dried up or receded. Nothing except rodents live on the bare earth left behind, and even that will erode and become desert.

The survey did not calculate how many residents were affected by these environmental changes. However, Xin said the team often met locals who complained of recent problems with drinking water and pasture for their livestock.

In Dangqu, Xin employed a local Tibetan as an assistant, who once told him: “We used to have lots of wetlands and thick tall grass on the pastures. If you went riding in the morning the dew would soak your boots. Now it doesn’t even cover the earth.”


Yang Jibin is a reporter for Southern Weekend.

This article first appeared in Southern Weekend. 

Homepage photo by Daniel J Miller

 

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评论 comments

Default avatar
匿名 | Anonymous

现象?=危机?

出现了什么,接下来又会发生什么,发生了什么,我们要做出什么样的改变。
人类在很多时候并不就那么得聪明,人类更多的时候是在根据大自然的表现来做出反馈,只有招架之功,并无还手之力。以后,也许会连招架之功都没有。
我们应该知道人类行为的后果,甚至应该夸大这种后果才能挽救什么。
也许很多人不以为然。
但是,大家可以回头想想今年全国气候的变化异常,再也不会有明显的四季分明,再也不会有四季之间稳健地过渡。有的是不确定性,下一刻你不知道将会发生什么,人类面临着将会是一种无知的状态,等待着人类的也许只剩下惊讶。

Is a phenomenon the same as a crisis?

Things that have happened affect what will happen next. And these things affect the way that we change. Lots of the time human beings don’t act from intelligence. Most of the time we react based on natural instincts. We act in defense rather than in attack. In the future, perhaps we will not even be able to rely on our defenses.

By now should know the consequences of human behaviour, and we should even be exaggerating these consequences in order to save the planet. Many people don't agree with this opinion. However, everyone remembers how abnormal China’s climate has been this year. We know that there are no longer four distinctive seasons. Nothing is reliable. You never know what will happen next. Humans are facing a state about which they are completely ignorant. Perhaps the only thing left in store for them is shock.

Default avatar
匿名 | Anonymous

沧海一粟

人类消失,冰川世纪来临,地球复苏。
人类的历史仅是沧海一粟。

A drop in the ocean

Humans disappear. The ice era arrives, and the earth comes back to life. Human history is merely a drop in the ocean. Translated by 陈丽英 ( Anna)

Default avatar
匿名 | Anonymous

知道了这么多,怎么做

谈论环保伦理的人常持两大相关的论点:一、我们身处的地球非常脆弱······二、人类应该学习如何做这备受威胁的世界的照管者。这种观点无论有多大的善意,正好犯上自古已然的罪,就是骄傲,自命重要。我们不过是千万种生物得以中,并非什么照管者。大自然并非为我们而存,也不会顾念我们。我们对大地和月球广芒的岁月完全无能为力。所有亿万吨火力的核武器,不过是一颗十公里大小的陨石对地球的冲击力的十分之一。地球经得起那使恐龙消失的撞击而继续屹立。我们惧怕全球暖化,但按最极端的推算,暖化情况也比地球最茂盛的时期还要冷。我们肯定可以毁灭我们自己,千万的物种将与我们同归于尽,但我们对那些无数的微生物,还有以百万计品种的昆虫却一无影响。从时间场合的角度来看,地球绝对能照顾自己。
——摘自Stephen Jay Gould, Eight Little Piggies, New York: W W Norton
地球不需要我们,我们所做的一切,无非是在保护或者毁灭我们自己。面对排山倒海的环境生态危机,我们光有危机的意识还是不够,赶快行动。我们不努力也许不会为自己招致毁灭,但我们看不见的邻居和后代会碰到麻烦,为了他们我们甘愿付出吗?这是道德和人类精神的问题。

Knowing this much,what are we going to do about it?

People who talk about environmental protection ethics usually hold two interrelated arguments: firstly, that the planet we live is very fragile……and secondly, the humankind should learn how to take care of this threatened world. No matter how much goodwill this argument contains, it carries a big error: its arrogance. We are only one of ten million organisms and not some sort of caretaker. Nature doesn’t exist for us, nor does it care for us. We have nothing to do with the existence of the land and the moon. All the firepower from a millions tons of nuclear weapons, is only equal to 1/10 of the impact force that a 10 km diameter meteorite would exert on the earth. The earth stood up to the impact that made the dinosaurs disappear and still it continues to exist. We are afraid of global warming, but according to the most extreme projections, the extent of the warming is colder than the time when the earth was at its most flourishing.

Certainly, we will ruin ourselves, and millions of species will die with us, but we can do nothing to the numerous micro-organisms and millions of insects. From the perspective of time, the Earth is absolutely able to take care of itself. -----According to Eight Little Piggies, (by Stephen Jay Gould, Eight Little Piggies, New York: W W Norton) the earth doesn’t need us, all we can do is to protect or ruin ourselves. Facing a mounting ecological crisis, a sense of crisis is not enough, we need to take action as soon as possible. If we don’t work hard at this, we may not even affect ourselves, but our unseen neighbours and our offspring will meet with trouble. Are we willing work hard to do something for them? This is an issue of ethics and human spirit. (Translated by Tian Liang)

Default avatar
匿名 | Anonymous

下一个

黄河连年断流,长江源头遭到破坏,松花江、淮河的污染早已不再新鲜,试问,下一个不幸又会降临到哪条河流上?

Which is the next?

The Yellow River's flow has be interrupted in recent years, the source of the Yangtze River has been broken down and the pollution of the Songhua and Huaihe Rivers mean they will never be fresh again. I wonder which river will be the next to meet with misfortune?
(Translated by Tian Liang)