KEMAMPUAN RUANG TERBUKA HIJAU DALAM MEREDUKSI PENCEMARAN TANAH OLEH TIMBAL DI RING ROAD SELATAN YOGYAKARTA

The increasingly rapid development of Yogyakarta has resulted in a decline of environmental quality along the South Ring Road of Yogyakarta. The soil around the South Ring Road has been polluted by lead. Green Open Space (Ruang Terbuka Hijau�RTH) can reduce the lead content in the air, therefore it is assumed to potentially reduce lead contamination in the soil. The purposes of this study are (1) to identify the role of RTH in Reducing soil pollution by lead along the south Ring Road of Yogyakarta (2) to identify the relationship between vegetation density in open green space and the amount of lead content in the soil in order to recognize the role of RTH in reducing soil pollution by lead along the South Ring Road of Yogyakarta. middle (3) rear, at the back of RTH. Purposive sampling approach was applied on several RTH with various vegetation density. Each block of RTH was classified into three segment (1) front, closest to lead emission sources (2) Soil samples were taken compositely and analysed the lead content in soil using Spectrophotometer. In order to compare the vegetation densities and lead content in soil among RTH plots, One Way Anova was used for statistical analysis. The relationship between vegetation density and lead content in soil was analysed descriptively. of vegetation There are six variation density, which are, no tree, 558, 725, 1067, 1750, 1458 trees/ha. The lead content is 18.796, 10.228, 13.412, 24.053, 37.072, and 33.126 mg/kg, respectively. The vegetation density and lead content in soil were significantly different among RTHs with significance level is 0.03. The results showed that there are two types of relationship which are,(1) the open space without vegetation, RTH 1 and RTH 2, the higher vegetation density, the lower the lead content in soil (2) in the RTH 3, RTH 4, and RTH 5, the higher vegetation density, lead content in soil is also higher. Instead of only affected by vegetation density, the lead content in soil was affected by the number of vehicles, precipitation, and tree species. The lead content in soil decreased from the front segment to the rear segment