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Let’s begin with a quick overview of China’s geography, population trends, and economy (map, p. 361). The Chinese environment is complex and locally fragile. Its diverse geography includes the world’s highest plateau, some of the world’s highest mountains, two of the world’s longest rivers (the Yangtze and Yellow Rivers), many lakes, a long coastline, and a large continental shelf. Its diverse habitats range from glaciers and deserts to tropical rainforests. Within those ecosystems lie areas fragile for different reasons: for example, northern China has highly variable rainfall, plus simultaneous occurrences of winds and droughts, that make its high-altitude grasslands susceptible to dust storms and soil erosion, while conversely southern China is wet but has heavy rainstorms that cause erosion on slopes.
As for China’s population, the two best-known facts about it are that it is the world’s largest, and that the Chinese government (uniquely in the modern world) instituted mandatory fertility control that dramatically decreased the population growth rate to 1.3% per year by the year 2001. That raises the question whether China’s decision will be imitated by other countries, some of which, while recoiling in horror at that solution, may thereby find themselves drifting into even worse solutions to their population problems.
Less well known, but with significant consequences for China’s human impacts, is that the number of China’s households has nevertheless been growing at 3.5% per year over the last 15 years, more than double the growth rate of its population during the same period. That’s because household size decreased from 4.5 people per house in 1985 to 3.5 in 2000 and is projected to decrease further to 2.7 by the year 2015. That decreased household size causes China today to have 80 million more households than it would otherwise have had, an increase exceeding the total number of households in Russia. The household size decrease results from social changes: especially, population aging, fewer children per couple, an increase in previously nearly non-existent divorce, and a decline in the former custom of multi-generation households with grandparents, parents, and children living under one roof. At the same time, per-capita floor area per house increased by nearly three-fold. The net result of those increases in the number and floor area of households is that China’s human impact is increasing despite its low population growth rate.
The remaining feature of China’s population trends worth stressing is rapid urbanization. From 1953 to 2001, while China’s total population “only” doubled, the percentage of its population that is urban tripled from 13 to 38%, hence the urban population increased seven-fold to nearly half a billion. The number of cities quintupled to almost 700, and existing cities increased greatly in area.
For China’s economy, the simplest short descriptor is “big and fast-growing.” China is the world’s largest producer and consumer of coal, accounting for one-quarter of the world’s total. It is also the world’s largest producer and consumer of fertilizer, accounting for 20% of world use, and for 90% of the global increase in fertilizer use since 1981, thanks to a quintupling of its own fertilizer use, now three times the world average per acre. As the second largest producer and consumer of pesticides, China accounts for 14% of the world total and has become a net exporter of pesticides. On top of that, China is the largest producer of steel, the largest user of agricultural films for mulching, the second largest producer of electricity and chemical textiles, and the third largest oil consumer. In the last two decades, while its production of steel, steel products, cement, plastics, and chemical fiber were increasing 5-, 7, 10-, 19-, and 30-fold respectively, its washing machine output increased 34,000 times.
Pork used to be overwhelmingly the main meat in China. With increasing affluence, demand for beef, lamb, and chicken products has increased rapidly, to the point where per-capita egg consumption now equals that of the First World. Per-capita consumption of meat, eggs, and milk increased four-fold between 1978 and 2001. That means much more agricultural waste, because it takes 10 or 20 pounds of plants to produce one pound of meat. The annual output of animal droppings on land is already three times the output of industrial solid wastes, to which should be added the increase in fish droppings and fish food and fertilizer for aquaculture, tending to increase terrestrial and aquatic pollution respectively.
China’s transportation network and vehicle fleet have grown explosively. Between 1952 and 1997 the length of railroads, motor roads, and airline routes increased 2.5-, 10-, and 108-fold. The number of motor vehicles (mostly trucks and buses) increased 15-fold between 1980 and 2001, cars 130-fold. In 1994, after the number of motor vehicles had increased 9 times, China decided to make car production one of its four so-called pillar industries, with the goal of increasing production (now especially of cars) by another factor of 4 by the year 2010. That would make China the world’s third largest vehicle manufacturing country, after the U.S. and Japan. Considering how bad the air quality already is in Beijing and other cities, due mostly to motor vehicles, it will be interesting to see what urban air quality is like in 2010. The planned increase in motor vehicles will also impact the environment by requiring more land conversion into roads and parking lots.
Behind those impressive statistics on the scale and growth of China’s economy lurks the fact that much of it is based on outdated, inefficient, or polluting technology. China’s energy efficiency in industrial production is only half that of the First World; its paper production consumes more than twice as much water as in the First World; and its irrigation relies on inefficient surface methods responsible for water wastage, soil nutrient losses, eutrophication, and river sediment loads. Three-quarters of China’s energy consumption depends on coal, the main cause of its air pollution and acid rain and a significant cause of inefficiency. For instance, China’s coal-based production of ammonia, required for fertilizer and textile manufacture, consumes 42 times more water than natural-gas-based ammonia production in the First World.
Another distinctive inefficient feature of China’s economy is its rapidly expanding small-scale rural economy: its so-called township and village enterprises, or TVEs, with an average of only six employees per enterprise, and especially involved in construction and in producing paper, pesticides, and fertilizer. They account for one-third of China’s production and half of its exports but contribute disproportionately to pollution in the form of sulfur dioxide, waste water, and solid wastes. Hence in 1995 the government declared an emergency and banned or closed 15 of the worst-polluting types of small-scale TVEs.
China’s history of environmental impacts has gone through phases. Even already by several thousand years ago, there was large-scale deforestation. After the end of World War II and the Chinese Civil War, the return of peace in 1949 brought more deforestation, overgrazing, and soil erosion. The years of the Great Leap Forward, from 1958 to 1965, saw a chaotic increase in the number of factories (a four-fold increase in the two-year period 1957-1959 alone!), accompanied by still more deforestation (to obtain the fuel needed for inefficient backyard steel production) and pollution. During the Cultural Revolution of 1966-1976, pollution spread still further, as many factories were relocated to deep valleys and high mountains from coastal areas considered vulnerable in case of war. Since economic reform began in 1978, environmental degradation has continued to increase or accelerate. China’s environmental problems can be summarized under six main headings: air, water, soil, habitat destruction, biodiversity losses, and megaprojects.
To begin with China’s most notorious pollution problem, its air quality is dreadful, symbolized by now-familiar photographs of people having to wear face masks on the streets of many Chinese cities (Plate 25). Air pollution in some cities is the worst in the world, with pollutant levels several times higher than levels considered safe for people’s health. Pollutants such as nitrogen oxides and carbon dioxide are rising due to the increasing numbers of motor vehicles and the coal-dominated energy generation. Acid rain, confined in the 1980s to just a few areas in the southwest and south, has spread over much of the country a
nd is now experienced in one-quarter of Chinese cities for more than half of the rainy days each year.
Similarly, water quality in most Chinese rivers and groundwater sources is poor and declining, due to industrial and municipal waste water discharges, and agricultural and aquacultural runoffs of fertilizers, pesticides, and manure causing widespread eutrophication. (That term refers to growth of excessive algal concentrations as a result of all that nutrient runoff.) About 75% of Chinese lakes, and almost all coastal seas, are polluted. Red tides in China’s seas—blooms of plankton whose toxins are poisonous to fish and other ocean animals—have increased to nearly 100 per year, from only one in every five years in the 1960s. The famous Guanting Reservoir in Beijing was declared unsuitable for drinking in 1997. Only 20% of domestic waste water is treated, as compared to 80% in the First World.
Those water problems are exacerbated by shortages and waste. By world standards, China is poor in fresh water, with a quantity per person only one-quarter of the world average value. Making matters worse, even that little water is unevenly distributed, with North China having only one-fifth the per-capita water supply of South China. That underlying water shortage, plus wasteful use, causes over 100 cities to suffer from severe water shortages and occasionally even halts industrial production. Of the water required for cities and for irrigation, two-thirds depends on groundwater pumped from wells tapping aquifers. However, those aquifers are becoming depleted, permitting seawater to enter them in most coastal areas, and causing land to sink under some cities as the aquifers are becoming emptied. China also already has the world’s worst problem of cessation of river flows, and that problem is becoming much worse because water continues to be drawn from rivers for use. For instance, between 1972 and 1997 there were flow stoppages on the lower Yellow River (China’s second longest river) in 20 out of the 25 years, and the number of days without any flow increased from 10 days in 1988 to the astonishing total of 230 days in 1997. Even on the Yangtze and Pearl Rivers in wetter South China, flow cessation happens during the dry season and impedes ship navigation.
China’s soil problems start with its being one of the world’s countries most severely damaged by erosion (Plate 26), now affecting 19% of its land area and resulting in soil loss at 5 billion tons per year. Erosion is especially devastating on the Loess Plateau (the middle stretch of the Yellow River, about 70% of the plateau eroded), and increasingly on the Yangtze River, whose sediment discharge from erosion exceeds the combined discharges of the Nile and Amazon, the world’s two longest rivers. By filling up China’s rivers (as well as its reservoirs and lakes), sediment has shortened China’s navigable river channels by 50% and restricted the size of ships that can use them. Soil quality and fertility as well as soil quantity have declined, partly because of long-term fertilizer use plus pesticide-related drastic declines in soil-renewing earthworms, thereby causing a 50% decrease in the area of cropland considered to be of high quality. Salinization, whose causes will be discussed in detail in the next chapter (Chapter 13) on Australia, has affected 9% of China’s lands, mainly due to poor design and management of irrigation systems in dry areas. (This is one environmental problem that government programs have made good progress in combating and starting to reverse.) Desertification, due to overgrazing and land reclamation for agriculture, has affected more than one-quarter of China, destroying about 15% of North China’s area remaining for agriculture and pastoralism within the last decade.
All of these soil problems—erosion, fertility losses, salinization, and desertification—have joined urbanization and land appropriation for mining, forestry, and aquaculture in reducing China’s area of cropland. That poses a big problem for China’s food security, because at the same time as its cropland has been declining, its population and per-capita food consumption have been increasing, and its area of potentially cultivatable land is limited. Cropland per person is now only 0.1 hectare, barely half of the world average, and nearly as low as the value for Northwest Rwanda discussed in Chapter 10. In addition, because China recycles very little trash, huge quantities of industrial and domestic trash are dumped into open fields, polluting soil and taking over or damaging cropland. More than two-thirds of China’s cities are now surrounded by trash whose composition has changed dramatically from vegetable leftovers, dust, and coal residues to plastics, glass, metal, and wrapping paper. As my Dominican friends envisioned for their country’s future (Chapter 11), a world buried in garbage will figure prominently in China’s future as well.
Discussions of habitat destruction in China begin with deforestation. China is one of the world’s most forest-poor countries, with only 0.3 acres of forest per person compared to a world average of 1.6, and with forests covering only 16% of China’s land area (compared to 74% of Japan’s). While government efforts have increased the area of single-species tree plantations and thereby slightly increased the total area considered forested, natural forests, especially old-growth forests, have been shrinking. That deforestation is a major contributor to China’s soil erosion and floods. After the great floods of 1996 had caused $25 billion in damages, the even bigger 1998 floods that affected 240 million people (one-fifth of China’s population) shocked the government into action, including the banning of any further logging of natural forests. Along with climate change, deforestation has probably contributed to China’s increasing frequency of droughts, which now affect 30% of its cropland each year.
The other two most serious forms of habitat destruction in China besides deforestation are destruction or degradation of grasslands and wetlands. China is second only to Australia in the extent of its natural grasslands, which cover 40% of its area, mainly in the drier north. However, because of China’s large population, that translates into a per-capita grassland area less than half of the world average. China’s grasslands have been subject to severe damage by overgrazing, climate change, and mining and other types of development, so that 90% of China’s grasslands are now considered degraded. Grass production per hectare has decreased by about 40% since the 1950s, and weeds and poisonous grass species have spread at the expense of high-quality grass species. All that degradation of grassland has implications extending beyond the mere usefulness to China of grassland for food production, because China’s grasslands of the Tibetan Plateau (the world’s largest high-altitude plateau) are the headwaters for major rivers of India, Pakistan, Bangladesh, Thailand, Laos, Cambodia, and Vietnam as well as of China. For example, grassland degradation has increased the frequency and severity of floods on China’s Yellow and Yangtze Rivers, and has also increased the frequency and severity of dust storms in eastern China (notably in Beijing, as seen by television viewers around the world).
Wetlands have been decreasing in area, their water level has been fluctuating greatly, their capacity to mitigate floods and to store water has decreased, and wetland species have become endangered or extinct. For example, 60% of the swamps in the Sanjian Plain in the northeast, the area with China’s largest freshwater swamps, have already been converted to farmland, and at the present ongoing rate of drainage the 8,000 square miles remaining of those swamps will disappear within 20 years.
Other biodiversity losses with big economic consequences include the severe degradation of both freshwater and coastal marine fisheries by overfishing and pollution, because fish consumption is rising with growing affluence. Per-capita consumption increased nearly five-fold in the past 25 years, and to that domestic consumption must be added China’s growing exports of fish, molluscs, and other aquatic species. As a result, the white sturgeon has been pushed to the brink of extinction, the formerly robust Bohai prawn harvest declined 90%, formerly abundant fish species like the yellow croaker and hairtail must now be imported, the annual take of wild fish in the Yangtze River has declined 75%, and that river had to be closed to fishing for the first time ever in 2003. More generally, China’s biodiversity is very high, with over 10% of the world’s plant and terrestrial vertebrate species. However, about one-f
ifth of China’s native species (including its best-known one, the Giant Panda) are now endangered, and many other distinctive rare ones (such as Chinese Alligators and ginkgos) are already at risk of extinction.
The flip side of these declines in native species has been a rise in invasive species. China has had a long history of intentionally introducing species considered beneficial. Now, with the recent 60-fold increase in international trade, those intentional introductions are being joined by accidental introductions of many species that no one would consider beneficial. For example, in Shanghai Harbor alone between 1986 and 1990, examination of imported materials carried by 349 ships from 30 countries revealed as contaminants almost 200 species of foreign weeds. Some of those invasive plants, insects, and fish have gone on to establish themselves as pests and weeds causing huge economic damage to Chinese agriculture, aquaculture, forestry, and livestock production.