The physicochemical assessment study was carried out to assess the soil quality in Ship-breaking yards of Chittagong region, Bangladesh.
In order to study the different physicochemical parameters, soil samples from thirty Ship-breaking yards were collected and analyzed
during the period 2011-2012. Collected soil samples were analyzed for the following parameters: pH, EC, soil salinity, nitrogen, potassium,
chloride, phosphate, nitrate, nitrite, cadmium, chromium, arsenic, cobalt, copper, iron, lead, manganese, nickel, silver and zinc using the
procedure outlined in the standard methods. The laboratory findings were compared with the recommended values set by the control area
and standard calculated on the World Scale. The ranges of different physicochemical parameters obtained are as follows: pH: 4.17-6.92,
EC: 1722-5600 µS cm-1
, soil salinity: 16651.7-54152, N: 115-1205 mg kg-1
, K: 693.75-812.45 mg kg-1
, chloride: 1900-7500 mg kg-1
,
phosphate: 8.36-34.84 mg kg-1
, nitrite: 0.03-8.41 mg kg-1
, nitrate: 0-74.05 mg kg-1
, iron: 1250-10057 mg kg-1
, manganese: 0-158.90 mg kg1
, chromium: 0.6-65.2 mg kg-1
, cobalt: 5.75-24.45 mg kg-1
, nickel: 16.30-162.2 mg kg-1
, copper: 0-295.65 mg kg-1
, zinc: 33.25-305.10 mg
kg-1
, silver: 4.60-132.45 mg kg-1
, cadmium: 0.55-3.95 mg kg-1
, lead: 0-137.05 mg kg-1
, arsenic: 0.0152-0.9505 mg kg-1
. Soil nutrients like
N, K were found in the level below that of the control area and standard calculated on the World Scale. Trace and heavy metals like Ag, As,
Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn were found very much higher than the control area and standard values set by World Scale. The
anion like nitrate, nitrite, phosphate for which no standard values are recommended by World Scale are also not in good conditions and the
concentration of chloride was very higher than the control area and the standard. From Pearson Correlation program, significant positive
and negative correlations were found for different parameters. These assessment data indicated that the soil of Ship-breaking yards in
Chittagong region are highly polluted which are continuously polluting the Coastal Zone, sea and the rivers of Chittagong, especially the
water of Karnafuli River is being polluted greatly. The polluted water of the Karnafuli River may affect the biodiversity of the Halda River.
Results from this study show that discharges from the broken Ships are highly toxic in nature. This affects not only the soil, aquatic
environment and human beings of the surroundings but also poses a serious threat to ground and surface water resources of the adjoining
areas and coastal zone of Chittagong, Bangladesh.
Key words: Physicochemical assessment, soil pollution, Ship-breaking area in Chittagong region, Bangladesh.
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