Heavy Metal Level and Macronutrient Contents of Roadside Soil and Vegetation in Umuahia, Nigeria

摘要

This study investigated the metal level and macronutrient content of roadside soil and vegetation as influenced by vehicular emission. Soil and plant samples were collected from 1, 5 and 10 m sampling positions in a randomized complete block design (RCBD) from FRIN, NRCRI, ISIALA and confrol. Levels of Pb, Cd and Ni in soil and plants were 0.20-28.8, 0.08-8.90, 0.20-4.10 mg/kg and 0.01-11.10, 0.07-2.70, 0.02-0.83 mg/kg, respectively. The concentrations of Pb, Ni, and Cd were significantly (P < 0.05)higher in leaves of Gmelina arborea (11.10, 0.83 and 2.70 mg/kg) followed hy Psidium guajava (9.00, 0.50 and 1.80 mg/kg) sampled at FRIN. Soil N (0.34 cmol/kg) was highest (P < 0.05) in 10 m at NRCRI, K (146.0 cmol/kg) in 10 m at ISIALA while P (71.0 cmol/kg) was highest in 10 m at NRCRI and ISIALA. In plant leaves, P (42.0 cmol/kg) and K (81.0 cmol/kg) were highest (P < 0.05) in Alchornea cordifolia and Harungana madascariensis, respectively. The result shows that the concentration of Cd in soil was substantially high and must have affected litter decomposition, mineralization and nufrient characteristics of the soil and uptake by plants.