|
亚洲时报：荒芜的土地--中国的水资源危机（共四部分）
【中文标题】荒芜的土地：中国的水资源危机 第一部分 － 中国的河流之死
【原文标题】The Ruined Land: China's Water Crisis. PART 1: The death of China's rivers
【登载媒体】亚洲时报
【原文链接】http://www.atimes.com/atimes/China/EH26Ad01.html
【译者】满仓
回溯到久远的历史以前，中国这片土地要比现在更温暖、更潮湿，长江北部生活着大象、犀牛和鳄鱼等动物。经过五、六千年的森林砍伐和湿地取水，这里的气候已经变化，地表的景色也已经发生了改变。根据世界银行的报道，中国的实际和潜在沙化比率为世界之最。
环境的加速变化在黄河，中国汉族文化的核心地带，最为明显，这条河实际上已经消失了。现在，中国在进行一项或许是世界历史上最大的河流改道工程，在三峡大坝的北边要修建一条运河，把黄河水引向中国北方。这项耗资500亿美元的南水北调工程需要重新安置40万在附近居住的农民，其中180万人已经沿长江畔安置完成。
现在中国发现自己似乎是精神分裂般地在同时做两件相反的事情。一方面，中国正在进行一项世界上最大的河流改道工程，这是三峡大坝项目其中的一个部分，这项工程会截流从武汉到重庆600公里的河水。与此同时，政府官员似乎也意识到了中国面临的环境威胁，比如建设三峡大坝的副作用。因此在疯狂地征用粮食耕地，而要求农民在光秃秃的山上植树造林，试图阻止土地沙化和洪水的发生。
这项宏伟的工程原因是几个世纪以来对环境的错误利用，并且这样的错误在共产党执政后更加变本加厉。公元前7世纪黄土高原地区的森林面积就开始缩小，这引起了土地被侵蚀的现象，频发的洪水让这个国家的筑堤修坝工程一直持续到今天。黄河这个名字就来自于河水中的污泥所造成的颜色，像中国其它的河流一样，它的河床高度已经危险地远远超过周围地势的高度。
第一个共产党时代大坝建设高峰项目主要集中在黄河流域，比如三门峡大坝工程，前后共修建了46座堤坝。但是更多的工程导致了更差的河水。除了雨季的几个月期间，黄河现在仅仅剩下了一个名字，一般情况下，在距离入海口还有1000公里的地方河水就干涸了，这对工业和农业生产起到了长久的削弱作用。黄河所遭受的命运正在淮河上重演，淮河流域生活着1500万人。1950年发生了几次灾难性的洪水之后，毛泽东发布了“要高山低头，要河水让路”的命令。就像当代的暴君一样，共产党动员了无数的资源和人力，修建了36个大坝、159个小坝和4000个拦河坝。
共产党宣称“人定胜天”，但结果是曾经肥沃的土地被干旱和凶猛的洪水变成了荒地。有记录的一次最长干旱期是1999年的247天，这让城市和村镇不得不修建更多的水库和蓄水池，或者打井汲取越来越深的底下蓄水层。
尽管大规模的工程建设被吹嘘为共产党执政后最伟大的成就标志，但是目前为止已经有3000个堤坝倒塌，包括淮河水域上的堤坝。1975年8月，石漫滩大坝和板桥大坝溃堤，24万人因此丧生。
结果是中国三分之二的城市缺乏水资源，剩下的城市也遇到了类似的威胁，比如山西省会太原市。上世纪建立的满洲里也发生过同样的问题。另外的一个例子是天津，它是坐落在海河旁边的北方海港和工业城市。海河早已经消失，只剩下了一个名字，因为河水都被分流到其它地方。几年以前，流经市中心的海河水实际上就是来自黄河的分流，而黄河现在已经没有自己的河水了。
在修建了30座大坝和蓄水池来为自己供水之后，这个中国第三大城市在70年代被迫把160公里的滦河水引向北方。20年后的1999年，新出现的危机又让天津把来自黄河645公里的河水引向南方。
汇入海河的300条支流现在都已经干涸，这给在海河流域生活的1200万人口带来了灾难性后果。而且，化学农药、工业废水和城市废弃物让蓄水池中的水源无法饮用。绝望中的天津政府命令上百名政府官员沿着岸边巡逻，以阻止污染水源的行为。
天津关闭了公共浴池、桑拿和其它娱乐设施，并且定量给每个居民每月分配8立方米的水。超过这个城市一半人口的9百万人都是农民，他们缺少足够的水来种植农作物、饲养水产和家畜。
整个华北平原是中国一半小麦的出产地，这里的360万口井已经干涸，这些井大部分是用来灌溉的。地下含水层的水分被逐渐排干，现在的地下水位距地表90米，而且每年都在下降3到6米。天津60％的地区都受到地下水位下降问题的困扰，如果中国北方的缺水问题无法得到解决，至少2000万农民就要停止生产。
水质也是一个大问题。中国因城市扩张而产生的每年200亿吨城市污水大部分都直接排进河水和湖水中。中国现在持有一个不光彩的记录，它的水污染排放总量等于美国、日本和印度的总和。专家的计算结果显示，7亿中国人的饮用水中含有超过标准比例的动物和人类排泄物，没有人了解这到底意味着什么。政府不鼓励任何机构在这方面进行深入研究，但是甲肝、痢疾、肝癌、胃癌和食道癌的高发病率可能与污染有关。
由于无法使用到河流和蓄水池中的水源，很多工业城市不得不使用没有处理过的工业废水来灌溉农作物，尤其是蔬菜。
在云南省会昆明市，人们根本不会想到干旱的问题，因为城市旁边就是亚洲最大的一个淡水湖。但是自从第一个排放废水的工厂自1990年建立以来，昆明市90％的废水未经处理就被排放到湖水中。尽管当地政府已经投入了数十亿美元试图进行清理，但是现在湖水已经无法饮用了。从80年代开始，昆明就在使用从80公里外松花坝蓄水池中引过来的水源。现在，这个拥有140万人口的城市准备扩张，它必须要投入更大的工程项目从其它河流中引来水源，比如向北190公里处的金沙江。
中国大部分的湖泊、水库、运河和河流都覆盖着厚厚的藻类或水葫芦，即使长江这样通行量极大的河流中的水也不可饮用。江畔的城市都不使用江中的水，而是从远处的水库分流水源或者钻取地下水。上海正是因为过度开采地下水，导致市中心地区在过去40年里下沉了1.7米。
一些人预测，再过20年长江也会步黄河的后尘。当你坐飞机经过长江中下游流域的时候，太阳反射的光线会让你发现江水被分割成数千个小池塘、湖和耕地，这也是一种暗示，表明这里曾经是多么广大的一片湿地。无数次的引流排水把长江变成了一个个用堤坝围起来小池塘网络。从1949年开始，长江的流域面积缩小了三分之二，土地的面积增加了。在短短50年的时间里，长江中下游的湖泊面积从18000平方公里缩减到7000平方公里。
大量的表层土壤被冲击而下——1998年夏季的洪水带来了7亿吨的土壤——让水库和湖泊迅速被淤泥填塞，它们容纳洪水的能力大大下降（据统计，容量大约下降了80亿立方米）。中国第二大湖洞庭湖容量下降了50立方公里，几乎是1949年容量的一半。而且现在还在不断减少，变得越来越浅了。湖底平均每年升高3.7米，来源于1亿立方米的淤泥。
中国在修建大坝上面毫无意义的投入，在1998年洪水期间彻底现出了原形，这次洪水夺去了4000条人命，花费了政府360亿美元的资金。这些堤坝对防御洪水没有起到任何作用，而且还增加了洪水的频率和猛烈程度。即使是足够大的三峡大坝，也没有实质上的区别。
原文：
China at the dawn of history was much warmer and wetter than it is today, with elephants, rhinoceroses and crocodiles living north of the Yangtze River. Five or six thousand years of cutting forests and draining marshes have changed the climate to the point where the landscape has been devastated. China has the highest ratio of actual to potential desertified land in the world, according to the World Bank.
The accelerating speed of that environmental change is most evident in the Yellow River, the heart of Han Chinese civilization. The river has virtually disappeared. Now, in what may be the biggest water-diversion plan in history, China will build a canal north from the Three Gorges Dam that ultimately will tunnel under the Yellow River to bring water to dry northern areas of China. The US$50 billion south-to-north water diversion scheme will require the resettlement of up to 400,000 peasants along the three possible routes. Already 1.8 million have been resettled along the banks of the Yangtze itself.
China today is finding itself in the middle of schizophrenic attempts to do two opposing things at once. On the one hand, it is in the middle of by far the biggest water-diversion plan in history, of which the massive Three Gorges project, which will impound 600 kilometers of water reaching nearly from Wuhan to Chongqing, is only a part. At the same time, officials appear to have finally become aware of the environmental depredation China faces, and the damage that dams cause, and are frantically stopping farming and resettling villagers to plant forest in an effort to halt desertification and flood damage on denuded hills.
The need for the massive projects is the result of centuries of environmental misuse that accelerated when the communists took power. Soil erosion as a result of rapid deforestation on the Loess Plateau started in the 7th century BC. This led to dangerous floods and in turn to a dike-building program that continues to this day. The very name Yellow River (Chinese Huang He) comes from the silt, which, like most of China's rivers, has now raised its bed to dangerous levels far above the surrounding plain.
The first big dam-construction projects of the communist era, such as the Sanmen Xia Dam, concentrated partly on the Yellow River, where a cascade of 46 dams was started. Yet the more engineering took place, the worse the river became. It now exists only in name, except for a couple of months during the rainy season, causing a prolonged and permanent shortage crippling industry and agriculture. It usually runs dry about 1,000km from the sea. What happened to the Yellow River was then repeated in the Huai river basin, home to 150 million people. After disastrous floods in 1950, Mao Zedong ordered "the mountains to bend their tops, and the rivers to give way". Like latter-day pharaohs, the party mobilized enormous resources and manpower into building 36 big dams, 159 smaller dams and 4,000 locks and barrages.
"Man must conquer nature," declared the Party, but the result was that a once-fertile plain was wrecked by droughts alternating with violent flash flooding. The most extended period of drought was as long as 247 days in 1999, forcing cities and towns to build more reservoirs or to rely on wells chasing shrinking underground aquifers deeper and deeper underground.
Although such massive engineering achievements have been trumpeted as among the greatest symbols of communist state power, 3,000 of these dams collapsed, including many along the Huai River. In August 1975, the Shimantan and Banqiao dams gave way, killing 240,000 by some accounts.
The result is that two-thirds of China's cities are now short of water and the very existence of some, such as Taiyuan, the capital of Shanxi, is threatened. It is the same story in Manchuria, which was densely settled only in the last century. Another example is Tianjin, the port and industrial city that sits astride the Hai River on the North China Plain. The river has long since ceased to exist in all but name because so much has been diverted. A few years ago, the water running through the center of the city actually had been diverted from the Yellow River, which could ill afford to lose what it had.
After building 30 dams and reservoirs to supply itself with water, China's third-biggest municipality was forced in the late 1970s to divert the waters of the Luan River, 160km to the north. Twenty years later in 1999, a fresh crisis forced the city to divert all its water from the Yellow river, 645km to the south.
All but a handful of the 300 tributaries that feed into the Hai River are now dry, with dire consequences for a population of 120 million people in the Hai river basin. But agricultural runoff from chemical fertilizers, industrial effluent and urban waste have rendered the water in most of its reservoirs undrinkable. In desperation, Tianjin ordered hundreds of officials to patrol the river banks to prevent theft of the precious water.
The city has shut down public baths, saunas and other entertainment centers and rationed water to just eight cubic meters a month per person. More than half of the 9 million people in the Tianjin municipality are peasants who lack sufficient water to plant crops, raise fish or breed livestock.
Across the whole of the North China Plain, where half of China's wheat is grown, 3.6 million wells have been sunk, mostly for irrigation. The aquifer below is being steadily drained and the water table is 90 meters below the surface and dropping by three to six meters a year. Some 60 percent of the land in Tianjin municipality is plagued by subsidence. If there is no solution to the water shortage in northern China, at least 20 million peasants will be forced to stop farming.
Water quality is also a big problem. Most of the 20 billion tonnes of urban sewage that China's expanding cities produce each year is dumped straight into rivers and lakes. China now holds the unenviable record of producing as much organic water pollution as the United States, Japan and India combined. Experts calculate that 700 million Chinese consume drinking water contaminated with levels of animal and human waste that do not meet minimum state drinking-water standards. No one is sure what this means. Any research into the subject has been discouraged by the government but China's high rates of hepatitis A, diarrhea, and liver, stomach and esophageal cancer may be linked to the pollution.
Unable to use the water in the reservoirs or rivers, most industrial cities have been forced to use untreated industrial wastewater to irrigate crops, especially vegetables, grown in the suburbs.
In the city of Kunming, the capital of subtropical Yunnan province, there is no talk of drought, since the city is right next to one of Asia's biggest freshwater lakes. But until the first wastewater plant was built in 1990, 90 percent of Kunming's wastewater was pumped untreated into the lake. The lake water is now undrinkable despite several billion dollars having been spent trying to clean it up. Since the 1980s, the city has relied on water channeled from the Songhua Dam reservoir in the mountains some 80km away. Now, as the city of 1.4 million prepares to expand, it must invest in an even bigger engineering project to divert water from other rivers such as the Golden Sands, 190km to the north.
Most of China's lakes, reservoirs, canals and rivers are covered in a thick film of algae or clogged by water hyacinth. Even the mighty Yangtze's waters are undrinkable. None of the cities along its banks can use its waters but have to tap reservoirs far away or drill deep for water. Shanghai has drilled for so much water that land in the center of the city has sunk 1.7m in the past 40 years.
Some predict that within 20 years even the Yangtze will resemble the Yellow River. When you fly over the middle or lower Yangtze Valley, the sun sometimes reflects the water trapped in the thousands of ponds, lakes and paddy fields, giving a hint of how this was all once an immense swamp. Millennia of drainage work have reduced it to a network of interconnected lakes and waterways protected by dikes. Since 1949, two-thirds of the Yangtze Valley lakes have disappeared as more and more land has been reclaimed. The total surface area of lakes in the middle and lower Yangtze Valley has shrunk from 18,000 square kilometers to 7,000 in just 50 years.
So much topsoil is swept downstream - 700 million tonnes during the 1998 summer floods - that both reservoirs and lakes are silting up so quickly their capacity to contain the floodwaters is declining rapidly. The storage volume of these lakes has fallen by 8 billion cubic meters. Dongting Lake, the second-largest in China, has decreased by about 50 square kilometers to almost half what it was before 1949. And it has silted up too, becoming more and more shallow. The lake bed has been rising by 3.7 centimeters a year and about 100 million cubic meters of silt has been deposited.
The sheer pointlessness of the vast investment in dam building was brought home by the 1998 floods, which killed 4,000 people and cost the economy $36 billion. The dams have done nothing to stop the floods, which have been increasing in frequency and severity. Even the Three Gorges Dam, big though it is, will make no practical difference. |
狗仔卡
发表于 2009-10-27 13:59
提升卡
变色卡
抢沙发
千斤顶
显身卡
发表于 2009-10-27 14:38
不管怎么说 这个问题值得我们重视 特别是政府部门
