Soils from the Baia Mare zone and the heavy metals pollution

The pollution of the soils with heavy metals, Pb, Cu, Zn and Cd, was studied on a surface over 20.53km(2) of Baia Mare. The total concentration of heavy metals was measured in the upper horizon for the entire surface of Baia Mare city and for each pedogenetical horizon within the soil profiles up to 1.20 m depth in the industrial zones. In both industrial areals Romplumb and Cuprorn texture, pH, cation exchange capacity, base saturation, total carbon, the nutrient elements were determinated for each horizon in the soil profile. The total contents of Pb, Zn and Cd are higher in the eutricambosols and aluviosols from Romplumb area than in the luvosols and aluviosols from Cuprorn area. The total content of Cu is significantly for the luvosols and aluviosols in the organic horizon. The highest concentrations of the heavy metals analysed in the upper horizon of the soils are present in the eastern side, the industrial zones and in the south-western part on the location of the tailing dump. The spatial distribution of Pb shows a high degree of variability. In some cases, on very small surfaces were found excessive concentrations of 40.375 ppm and maximum values that are higher than the maximum allowable limit up to 60 times, close to Romplumb (6565ppm) and Cuprom (982ppm) metallurgical smelter factories. The average concentration of Pb over 2417.71 ppm, for the entire investigated area corresponds with the state of high pollution. Maximum concentrations of Cu which indicate this high level of pollution are over 400ppm-5823ppm are specific for the Cuprom area on a big surface arounds the influence zone of gaseous emissions, associated with albic luvosol type. The maximum values determinated for Cd (80-39ppm) in Cuprom area, 24.2-5.2ppm for Romplumb area and 15.13-3.05ppm in south-western part sustain the high pollution for the characteristic type of soils. The concentrations for Zn (6122-4513.2ppm) correspond with the state of increased pollution on small surfaces in Romplumb area and in south-western. part of the investigated zone. For Cd and Zn, in case of high value of acidity of the upper horizon, it took place the mobilization of metals within the soil profile. The maximum content of Cd is greater than the maximum allowable limit on the soil profile (3.17-21.5ppm). The maximum values for Zn (928ppm and 627ppm associated with maximum values for Cd: 50ppm and 40ppm) are related with B horizon of the eutricambosol.