II. THE ENVIRONMENTAL MONITORING SYSTEM IN SHANGHAI

[ II-A | II-B | II-C | II-D | II-E | II-F ]

B. The network of environmental monitoring

[ B | B-1 | B-2 | B-3 | B-4 | B-5 | B-6]

2. Air quality monitoring

The monitoring variables include SO2, NOx, TSP (including Pb), CO, dustfall (percentage of combustibles), sulphuration rate, fluoride, among which SO2 and TSP are basic variables. The rainfall monitoring variables consist of the measurement of rainfall, pH, conductance, SO42-, NO-3 , NH+, Ca2+, Cl-, M 2+, Na+, K+ and F-.

The monitoring approaches are categorized as continuous automatic monitoring and continuous indoor analyzing according to different ways of sampling. National specifications such as Air and Waste Gas Monitoring and Analyzing Approaches, and Ambient Air Monitoring Specifications define the detailed sampling procedure, the frequency and the analysis methods. Table 2 shows the specifications of the basic variables. 

Table 2. Methods of sampling and analysis in monitoring the basic variables of air quality

In Shanghai, six monitoring sites belong to the continuous automatic monitoring system, five of which are identified as national monitoring stations, positioned in districts of different urban functions. The last one is set up in the Dianshan Lake area for the purpose of comparison.

The monitoring sites employing continuous indoor analyzing methods are positioned with regard to the characteristics of the different areas in Shanghai. There are 24 sites for monitoring SO2, NOx and TSP, 143 sites for dustfall and sulphuration rate, 88 sites for fluoride, all with comparing sites in the Dianshan Lake area .

Figure 13. Sketch map of air monitoring stations in the urban area of Shanghai

Figure 14. Sketch map of air monitoring sites in the suburbs of Shanghai

In addition, 22 rainfall sites are set up, four of which are national sites. Variables such as pH conductance and rainfall volume are the basic ones. S042-, NO3-, NH+, Ca2+, Cl, M2+, Na+, K+ and F- are monitored at national sites at the first rainfall of each month, while the remaining sites only monitor the first four variables in the above list.

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