|Air and Water|
In an open China, Tibet is drawing more and more tourists from all over the world. Besides the unique culture and the strange land, many foreign tourists come to Tibet to see the bluest skies and breathe the purest air in the world. Their wishes are sure to be fulfilled. Many have been fascinated by the clear reflections of the blue skies, white clouds, snow- capped mountain tops and green woods in the limpid water surface and by the resplendent roofs of the temples in the sun. Evidently, air and water, both essential to human existence, keep their best quality in Tibet.
Statistics may seem dry but they mean science after all. As is monitored, discharges of industrial waste gas, waste water and waste materials in Tibet are of small amount. In 1993, in the whole Tibetan Autonomous Region the total discharge of waste gas was 1,474 million cubic metres, of which that of industrial waste gas accounted for 954 million cubic metres; the total discharge of waste water was 40.77 million tons, of which that of industrial waste water accounted for 25.77 million tons; solid industrial waste materials amounted to 260 tons, with cumulative heaps only totalling 76,000 tons.
For Tibet, with an area of 1.2 million square kilometers, this is really negligible. It is even far smaller than that of a medium-sized or small city in coastal China. What is more, a considerable proportion of the discharges has been treated. For instance, 100 per cent of the industrial waste gas has its dust particles removed; about half of the industrial waste water is treated, with the Yangbajain geothermal power station alone recycling 21,254,400 tons of its waste geothermal water.Lhasa is the political, economic and cultural centre of Tibet, with relatively dense population. The discharges of industrial waste gas, water and solid materials in the city account for 90 per cent of the total of Tibet. Nevertheless, Lhasa is the least polluted of China's cities, even though sometimes there is enormous amount of smoke because of religious activities and traffic noises in the daytime. A large-scale urban ecological project---the Midtrunk Canal---including water diversion and tree planting, will, together with the Lhasa River, surround the city with a watercourse, adding 150,000 square metres of water surface to the city. And a 5- kilometre-long shelter belt covering 800,000 square metres will appear. Data show that in Tibet far fewer sandstorms now occur than in the past.
Many noted rivers run along the Tibetan plateau. Except in the rainy seasons when the torrential rain would wash earth and sand from the mountains, all the rivers are charmingly clear for the rest of the year. Especially in the low-sea level southeast part of Tibet, where the rivers pass through wood-clad valleys, the green mountains and emerald water present very enchanting scenery. The water of Tibet's mother river, the Yarlung Zangbo River, and of its tributaries attains the first grade by state standards and is drinkable without any treatment. Even the Lhasa River, which runs past the capital of the Autonomous Region, has water of very good quality, too, for the colon bacillus averages below 500 per litre daily, the PH value is around 7, the saturation rate of dissolved oxygen is above 90 per cent and the content of cyanide, arsenic, lead and other toxic substances is all but zero. When the traditional ''Bathing Festival'' comes round in the seventh month of the Tibetan calendar, thousands upon thousands of Tibetans would bathe in the limpid ''sacred'' water most joyfully.
The Tibetan pleateau is dotted with about 1 ,600 lakes, all of which remain in their primaeval, unspoilt state, with no source of pollution in their vicinity at all. The ''Heavenly Lake'' , by the name of Namucuo, 4,700 metres above the sea level and with a water surface of 1 ,940 square kilometres, is the largest lake in Tibet. Fish swim in its vast expanse of clean water while birds fly and skim over the surface of it. Holding the lake holy, each year large numbers of Tibetans would walk round the lake for pilgrimage, with that activity in the Year of Horse, which comes round once every 12 years, being the most impressive.The latest such pilgrimage took place in 1990. The Yamzhuo Yumco Lake in south Tibet is noted for its abundance of fish, which is estimated at about 400 to 600 million kilogrammes. It is also the largest habitat in south Tibet for the waterfowls, such as swan, egret, gull and wild duck. Along its sides there are about 70,000 hectares of meadow with lush grass, a most wonderful pasture for sheep and cattle.
Tibetan environmentalists may take pride in the fact that so far no case of pollution, acid rain or man-made radioactivity has occurred in Tibet. As verfied by the Environmental Protection Bureau of the Tibetan Autonomous Region, the natural radioactivity of the various areas in Tibet meets the State "radiation protection" requirements; it is on a par with the normal case of world land areas and in agreement with the report of the UNSCEAR.