Characteristics Of Atmospheric Particulate Matter In Main Traffic Road Of Chongqing

This paper adopted sampling way of single point method, vertical profiling method and horizontal profiling method. In autumn, winter, spring and summer of 2003—2004 four seasons, seven traffic main roads of jiangbei guanyinqiao turnplate, door foraway of culture palace zhongshang three road, Changjiang river bridge south head before amusement park, door foraway xindongfu caiyuan road, door foraway Shongshi dispart institute Shixiao road, Yanggongqiao toll station in yuhe speedway, honhjin road jiazhou garden before door were monitored using sampler of low flow made in America (Air Metrics Minivol Portable, Model: 4.1) in order to gather samplers of atmosphere paniculate matter (PM10/PM2.5) in the Chongqing downtown area. And simultaneity attained sampling data of atmospheric contamination SO2, NOx, NO2, NO, CO, O3 and PM10 by automatic instruments made in France. By Single point sampling at roadside attained PM2.5/PM10 ratio and quality concentration of particulate matter. And using advanced instrument analyzed organic carbon, element carbon, chemistry element, water-solubility ion of particulate matter. Researched polluting situation and one another relation of organic carbon, element carbon, chemistry elements, water-solubility ions of particulate matter. By space distribution of particulate matter at roadside were sampled, in order to attain horizontal and vertical distribution of particulate matter concentration (PM10/PM2.5) .mostly results showed such as:1, In autumn and winter, monitoring data air quality of seven traffic main roads were monitored by automatic instruments made : The results indicated that SO2, NO2, CO and PM]0 had phenomenon of exceeding criterion. Pollution of SO2, NO2, CO were severer at winter than autumn, but PM10 were severer at autumn than winter. From seven sampling roads each polluting gene participate ratio showed, each road PM10 was the chiefly pollutant, secondly was SO2, NO2 ; From seven sampling roads various polluting burthen ratio showed, SO2 was the severest at door foraway culture palace, NO2 was the severest at jiazhou garden before door, and PM10 was the severest at guanyinqiao turnplate. As a result of each sampling road PM10 was the chiefly pollutant, PM10 choosed characteric pollutant was studied, Daily change of PM10 was: The most value appeared at 9-11, next appeared at 17-18, after 22 had addad, till after 2 had dropped.2, PM10 quality concentration of seven traffic main roads season changing was relatively patency , the most concentration appear in autumn, averaging value was 418.75ug/m3; the lowest concentration appear in summer, averaging value was 203.53ug/m3; yearly averaging value was 319.60ug/m3. By space distribution,PM10 yearly most averaging value was at Jiangbei guanyinqiao , averaging value was 412.2ug/m3; the lowest was speedway yanggongqiao toll station, averaging value was 232.14ug/m3; but PM2.5, season changing and space distribution wereapproximately sameness, as well as the most concentration appear in autamn, averaging value was 269.24μg/m3; the lowest concentration appear in summer, averaging value was 138.08μg/m3; yearly averaging value was 208.54μg/m3. By space distribution,PM2.5 yearly most averaging value was at Jiangbei guanyinqiao , averaging value was 253.96μg/m3 .Three sampling roads of Changjiang river bridge south head, speedway yanggongqiao toll station, jiazhou garden were approximately sameness, value was around 180μg/m3.3, The ratio of mass concentration PM2.5/PM10: the ratio value range was 0.52-0.85,average value was 0.66.The most ratio value came forth speedway yanggongqiao toll station, value was 0.78; the lowest ratio value appeared jiazhou garden, value was 0.57.4, Horizontal distribution and vertical distribution of PM10 concentration had a significant reduction with distance, but PM2.5 was not significant. Such as:Vertical distribution: matter concentration of PM10 did not more change between 36 meter and ground, At 55 meter sampling plot had a fall trend, 100 meter sampling plot dropped to 64% of ground; but matter concentration of PM2.5 had no more change , however at 100 meter plot had a fall trend, dropped to 55% of ground's most concentration.Horizontal distribution: matter concentration of PM10 had a significant reduction with distance, at 40 meter plot had a evidence decrease, dropped to 76% of 1 meter plot, at 60 meter plot decreased to 48.78% of 1 meter plot, lessen more half of 1 meter plot, between 1 and 20 meter plot PM10 had not a fall trend.5, The temporal variation of ions mass concentration of PM10 in seven main traffic roads: The concentration of cations (Na+,NH4+,K+,Mg2+,Ca2+) and anions such as CPand NO₃^- have the same temporal variation, which is higher in spring than that in summer. On the contrary, the concentration of F'and SO₄²- in summer is higher than that in spring. The total average concentration of water-soluble ions is 90.23μg/m3, which accounts for 37.6% of PM10. Among them, NH₄⁺ accounts for 6.6% of PM10, Ca²+accounts for 7.5% of PM10, NO₃^-accounts for 4.6% of PM10, SO₄²-accounts for 12.4% of PM10, respectively. In spring, the sum concentration of anions almost keeps balance with the sum concentration of cations. However, in summer, the balance between anions and cations is disturbed due to the high concentration of SO₄², which may reflect that SO₄²' originated from secondary pollution accounts for a relatively large ratio to ions components of PM10.The temporal variation of ions mass concentration of PM2 5 in seven traffic main roads: The concentration of cations (Na+,NH4+,K+,Mg2+,Ca2+) and anions such as SO₄² Cl^-and NO₃^- have the same temporal variation, which is higher in spring than that in summer. On the contrary, the concentration of F" in summer is higher than that in spring. The total average concentration ofwater-soluble ions is 53.31μg/m3, which accounts for 31.8% of PM10. Among them, NH4+ accounts for 6.5 % of PM25, Ca2+accounts for 3.0% of PM25, NO₃^-accounts for 4.4% of PM2.5, SO4²- accounts for 13.4% of PM25, respectively. Apparently, in fine particles, the proportion of Ca2+decreased, while the proportion of SO₄²-originated from secondary pollution increased. The ratio of [NO₃^-]/[SO₄²- ] in all seven main traffic roads is 0.40-0.52, which is relatively lower compared with the results of other study concerning traffic environment.6, Total carbon element of PM10 in seven main traffic roads averaged 89.43ug/m , accounted for 27.98% of PM10, thereinto, organic carbon averaged 68.96μg/m3, accounted for 21.58% of PM10, element carbon averaged 21.24μg/m^-3 accounted for 6.65% of PM10; The temporal variation of OC and EC in seven main traffic roads was approximately homology. Namely, OC and EC at shiliao road were the highest, in the next place, OC and EC at culture palace, jiazhou garden, speedway yanggongqiao, xindongfu, OC and EC at Changjiang river south head was little lowliness; and that Total carbon element of PM25 in seven main traffic roads averaged 67.88μg/m3, accounted for 32.31% of PM25, thereinto, organic carbon averaged 52.00μg/m3, accounted for 24.75% of PM25, element carbon averaged 15.89μg/m3, accounted for 7.56% of PM2.5 ; The temporal variation of OC and EC in seven main traffic roads was approximately homology. namely, OC and EC at culture palace were the highest, in the next place, OC and EC at shixiao road, guanyinqiao, speedway yanggongqiao, xindongfu, jiazhou garden and Changjiang river south head.The ratio temporal variation of OC/EC in all seven main traffic roads, in sampling period, the ratio of PM10 and PM25 was higner than 2.7, Total chemistry element of PM10 in seven main traffic roads averaged 69.22μg/m3, accounted for 21.66% of PM10, and total chemistry element of PM2.5 averaged 20.36ug/m3, accounted for 9.76%of PM2.5 The temporal variation of daily equal mass concentration was : the autumn was higher the winter and the spring, the summer was the lowest in a year; Ca, Al, Fe, Mg and Ti evidently comprised in coarse particulate matter PM(2.5-10) commonly, these elements were taken for the crust element, S, Br, V, Cr, Ni, Cu, Se, Cd and Pb evidently comprised in fine particulate matter PM2.5, commonly, these elements were bring from artificial activity, Na, Cl, K, Zn, As, Co and Mn were almost in coarse particulate matter and fine particulate matter, usually, considered to come from artificial and natural activities.8, Chemistry mass balance of PM10 and PM25 in traffic setting, in PM10, water-solubility ion accounted for 37.6%, total carbon element accounted for 27.98%, chemistry element accounted for 21.66%, else chemistry component occupied 12.76%, in PM2 5, water-solubility ion accounted for 31.8%, total carbon element accounted for 32.31%, chemistry element accounted for 9.76%,...