In this study,
irrigation with water containing heavy metals (copper, lead and zinc)
was simulated for soils from two areas around the city of Nablus; Salim
and Deir Sharaf Plans are already made to apply treated wastewater from
Nablus municipality to these two areas. As industrial effluents are
usually included in wastewater flow to these areas, there is a risk of
soil and groundwater pollution by heavy metals in these areas. Soils
from these areas were sampled and analyzed to study their chemical and
physical properties. Simulation of irrigation with water containing
heavy metals was done using soil columns of 2 meters height.
The results of chemical and physical analysis of these soils showed that
the soils are classified as clay loam with good chemical and physical
properties. The salinity of these soils was found to be low, the pH was
between 7 and 8, the calcium content was high while the sodicity was
low. Soils were found to be calcareous soils. These properties make
these soils good agricultural soils and suitable for most agricultural
crops. The drainage conditions of these soils were found to be good.
Their permeability is good due to their good structure resulting from
low sodium and high calcium contents. Simulation of irrigation with
water containing heavy metals showed an increase in heavy metals
concentrations in soil and in leachate with increasing the addition of
heavy metals in irrigation water. Heavy metals concentrations increased
with depth and time of application. Although these soils were classified
as clay loam, but their self-purification was highly affected by the
formation of cracks due to their expansion and shrinkage resulting from
wetting and drying patterns.
Therefore, especially near the surface of these soils, water flows
through these cracks at high rates without giving the soil enough time
to exchange many cations with soil solution.