II. THE ENVIRONMENTAL MONITORING SYSTEM IN SHANGHAI
B. The network of environmental 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.
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 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.