III. ENVIRONMENT MONITORING AND URBAN PLANNING
B. Urban comprehensive environmental harnessing
1. Reasons for the degradation of the urban environment
(a) Poor industrial structure
In 1995, the division of the three sectors in Shanghai was 2.4:57.5:40.1, indicating that industry still has a predominant position in the local economy. As a result, a heavy volume of industrial pollution is -inevitable. For example, 462 billion m3 of industrial waste gas was emitted that year, including 381.5 thousand tons of SO2, 1161 million tons industrial waste water was discharged, and 13.68 million tons of solid waste was generated. All exerted tremendous pressure on the environment.
In the early years of industrialization, industry was the fastest way of accumulating capital and the most powerful means of enhancing the attractions of the city. However, unless this development policy favourable to industry proceeds in harmony with the environmental capacity, serious industrial pollution will endanger the health of the city. London, Chicago and Tokyo have already experienced this nightmare which other cities should endeavour to avoid. Therefore, encouragement of development of the tertiary sector and the shift of urban function are basic requirements for the balanced growth of a city. Naturally, this process, if followed, would fundamentally reduce industrial pollution and promote economic and environmental coordination, especially in Shanghai—the old industrial base. The tertiary sector in Hong Kong had a 57 per cent share of its economic output in 1960, and this figure increased to 67 per cent in 1977. Meanwhile, Hong Kong emerged as a new international economic centre. Its secondary sector appeared to recede but in fact was shifted to the much more open hinterland—the Pearl Delta. So, while industry continued to provide the solid backing for Hong Kong's financial and economic growth, the urban environment was protected and improved.
(b) Irrational location of productivity
According to spatial patterns, industrial regions are divided into three types: industrial site, industrial block and industrial zone. So, in the context of these characteristics, the following problems can be identified with regard to the spatial location of many Shanghai industries:
(c) Unfavourable energy structure
According to SEPB estimates, the energy structure will not see any meaningful improvement until well after the year 2000. Coal will continue to be the main energy source. If the power generated reaches 12 million kwh, added to the use of more than 10,000 industrial furnaces and kilns, the coal consumption in Shanghai will hit 48-52 million tons by 2000 and 85 million by 2010. Therefore the annual emission of SO2 will reach 1.4 million tons, and smoke and dust will be around 670,000 tons.
Facing such an unfavourable energy structure and consumption, the concentration of S02, dust fall and NOx covering a large part of the urban area will exceed class three level according to national standard, and will even double in some areas if urgent counter-measures have not been adopted such as burning technology of coal or introduction of energy outside Shanghai.
(d) Huge debts in urban infrastructure
Huge debts in urban infrastructure were accumulated during the 30 years after 1949 due to over- emphasis on "production first life, second". Only after the reform and opening policy took effect did investment in urban infrastructure show a modest increase which remained between 2-3 per cent of GDP-(figure 33).
Figure 33. Growth of investment in urban infrastructure in Shanghai
This percentage increased to 5 per cent after 1985, however, and large scale investment began in 1993 when the percentage climbed to 11 per cent. But the accumulation of decades of debt is so large that it cannot be repaid for many years. For instance, in 1992, the land-use proportion of roads was only 0.7 per cent, the density of roads was 0.8 km/sq km, average road per capita in Shanghai was one third to one half of that of Beijing and Tianjin, one quarter of Tokyo and Paris, one eighth of London and one sixteenth of New York. Yet, the number of automobiles never ceased to increase, causing severe traffic jams. The overloaded traffic resulted in an average vehicle speed of less than 10 km/h, aggravation of the level of exhaust gas pollution, and the appearance of photo-chemical pollution at certain crossings.
Wastewater treatment facilities were also in urgent need of attention. In 1992, the treatment rate of industrial waste water was 77 per cent, while the rate of domestic sewage was 14 per cent. The coverage of the sewage system in the urban area was 47 per cent, but in the Pudong New Area it reached only 10 per cent. All these deficiencies were very embarrassing for such a large city.
The colour green symbolizes the adequacy of the urban eco-environment. However, the green coverage in 1996 was 17 per cent, and the average green area per capital only 1.92 sq m. The improvement of the residential environment, living standards and the investment environment cannot be achieved without huge progress in afforestation in Shanghai.
In addition, the unique urban climate in Shanghai has a negative impact on ambient air environment According to research, the urban heat island effect is very significant under stable meteorological conditions (figure 34). Its maximum intensity can exceed 6 degrees centigrade. The unique characters of radioactivity and thermodynamics of ground surface along with the huge consumption of energy and generation of heat, combine to form this strong heat island effect. Further studies reveal that several other “islands” can be observed under the heat island effect, such as dry island, moisture island, rain island and turbidity island. They are interrelated. For example, the heat island brings about converging flows and thermodynamic turbulence which increase low-level clouds hanging over the city. As a result, the turbidity island is easy to form, and air pollutants gather in the urban area further aggravating air pollution.
Figure 34. The heat island effect in Shanghai
According to statistics, the emission of SO2, smoke and dust in the urban area is 2.4, 2.7 and 2.3 times that of the suburbs respectively. The turbidity of air is also much severer than in the suburbs. Therefore, when spring and winter come, the heat and turbidity islands accumulate the air pollutants in the urban area and increased concentration results.