ANALISIS PERUBAHAN KONSENTRASI NITROGEN DIOKSIDA (NO2) PADA AREA BERVEGETASI DAN TIDAK BERVEGETASI DI JALAN SIMPANG SUSUN

Abstract

The Interchange of highway is the intersection of several roads that consists of numerous road levels, ramps, loop, divergent paths, and convergent paths. It causes great number of traffic volume and releases abundant pollutant quantities especially when traffic congestion occurs. One of the pollutants emitted from transportation which affect human’s health is NO2. This research objectives were to analyze dispersion of NO2 gas pollutant from interchange road and to analyze the influence of local wind speed, distance, and traffic volume with NO2 concentrations at the surrounding of the interchange. Researches were conducted at Cikunir Interchange. Air sampling was conducted to measure NO2 concentration at elevation 1.5 m at distance 0 m, 10 m, and 75 m using Air Sampler Impinger. Results of research showed that the average NO2 concentration at the vegetated area was 33.68 μg/m3, while the average concentration of NO2 in the nonvegetated area was 94.05 μg/m3. Concentration of NO2 was analyzed with Griess-Saltzman method. From this research, the result of Independent Sample T Test showed that the average of NO2 concentration at the vegetated area was significantly different from the average of NO2 concentration in the nonvegetated area. NO2 gas concentrations at both sites have a tendency to decrease from the emission source (0 m) to a further location. The results showed that vehicle volume and wind speed have a significant affect on NO2 concentration at vegetated sites. In this case, increasing wind speed significantly reduce NO2 concentrations, however increasing vehicle number significantly increase NO2 concentrations in the area close to the road.