Part of a dense network of waterways crisscrossing the Yangtze Delta, such canals have provided transportation and irrigation for area inhabitants for more than 3,000 years. In the small plots behind their accommodation prague, farmers grow vegetables for sale in China’s now thriving private-market sector.
GOUGED by ravines and gullies, the northern reaches of the Loess Plateau each year contribute a share of the sediments that give the Yellow River its name. Seen during an August dry spell, a terraced basin near Datong in Shanxi Province (left) is threaded with watercourses that feed the Yongding River, also known as the Small Yellow River. Composed mainly of silts dating back to the late Pleistocene epoch, the loess deposits that cover the plateau are an average of 200 feet deep. Prevailing winter winds sweeping over the great bend of the Yellow River deposit the loess in successively smaller granules from northwest to southeast, with the finest soils accumulating around the ancient Wei River Valley in central Shaanxi Province-http://www.travelchinaguide.com/cityguides/shaanxi/.
Each year an average of 1.6 billion tons of this soil wash into the river. Three-quarters of that amount reaches the Yellow Sea. The balance builds up in the riverbed, causing the channel to rise continuously. Through the centuries it has risen between 15 and 40 feet above the surrounding plain. The river is contained by dikes, built higher each year. Over the past 25 centuries broken dikes have wreaked floods on the countryside with devastating regularity. One of the worst in history occurred in 1938 after Chiang Kai-shek’s Kuomintang troops breached the dikes to check the southward march of Japanese troops during the Sino-Japanese War. The tactic cost the lives of perhaps a million peasants, displacing millions more.
While the government has been encouraging agricultural settlement of northern plateau regions since 1949, many Chinese geographers believe that destruction of soil-holding grasses in the once pastured uplands carries a price too high for the environment. Marginal agriculture in areas like the badlands of the Ordos Plateau (above), they say, exacerbates the process of desertification, which in recent centuries has spawned whole new deserts both north and south of the Great Wall. Recognizing the problem but slow to curb new agriculture, the government has been waging a relentless struggle to anchor the soil by planting grasses and millions of trees. In the denuded hills of central Gansu Province (following pages) narrow catchment basins, called “fish scale pits,” have been dug to capture the rain to nourish young trees.
A PLUME of industrial waste (above) befouls the harbor of Shantou, a port city in Guangdong Province. Each year Chinese industries discharge millions of tons of raw sewage and thousands of tons of toxic wastes into their country’s rivers and offshore waters. Even before the economic reforms launched in 1982 to speed the nation’s development, all of China’s major rivers were seriously polluted—a situation that has now gone from bad to worse. Acknowledging the severity of the problem, the government has passed a number of laws to curb it, scoring a notable success with petroleum wastes.