مدل عددي ارزيابي پتانسيل خطر آلودگي هواي استان گلستان

A model for assessing air pollution potential hazard in Golestan Province

In an airshed without stationary and mobile recording of index pollutants density and emission, air pollution potential hazard assessing with quantiative experimental models provide a valuable basic data for determination of industry allocation regulations and emission standards of air pollution in Golestan province, a widespread weighted numerical model was prepared with 44 bio-physico-chemical effective parameters and implemented in the framework of 198 equi-poteial environmental units (a 44* 198 matrix). This model according to the effect of each parameter upon air pollution, contains three groups of parameters including I-decreasing (8,indicator of environment refinery capacity), 2-increasing (31, indicator of environment pollution susceptibility), and 3-decreasing-increasing parameters (8,related to critical limits or specific standards). Weight of each parameter was determined according to its relative importance in air pollution potential and exceeding from ambient air standard in a-3 to +3 graded scale, and also rate of parameter class (2 to 5 class) was determined on the range and allowable limit of ambient air standard in a I to 5 value scale. Total number or hazard index of air pollution in each environmental unit was calculated by multiplying of weight to rate of every parameter and sum of positive and negative values of all parameters, and finally divided to 5 classes. With implemenation of model with different data sources, the potential hazard of air pollution in Golestan province evaluated and mapped as choropleth on a semi-detailed level at 1:250000 scale. Results show that the province contains all of the 5 hazard classes of the model, and there are significant differences (at P<0.01 level) between number (and area of the polygons of hazard classes). This numerical model has actually a necessary spatial and thematic resolution for planning of air quality management and control. So that, there are close spatial fitness between high hazard classes with densely populated and urban-industry concentrated area of foot hill belt, and low hazard classes with less populated and rural-agricultural areas of province. Therfore, it is possible to calibrate the regional model via systematic watching and monitoring of index pollutants in different part of the province especially in the critical areas.