| Abstract: |
The objectives of this work are to augment the soil database of Port Said Governorate, elaborate remediation measures to deal with problems of salinity and heavy metal pollution, and manipulate data via remote sensing and GIS technologies to characterize soil suitability. Satellite images, Digital Elevation Model (DEM), and GIS were used to generate a physiographic map and soil mapping units. Spatial distribution of data were created using ArcGIS 9.2 software. The MicroLEIS with Almagra model was used to produce soil suitability maps for crop production. Selected soils were chemically loaded with heavy metals, and then metals were retrieved using EDTA, citric acid, and distilled water. Filtrates were collected, and the concentration Mn, Zn, and Pb was determined by ICP spectrometry. The clay mineralogical composition of soils was determined using x-ray diffraction. Furthermore, some water quality indicators of El-Salam Canal were spatially monitored for one year.The analytical data of the investigated 40 profiles comprising 184 soil samples, and the water analyses of the El-Salam Canal make it abundantly clear that most soil and water resources of Port Said Governorate are not prime resources. Many soils are polluted with degrading amounts of salinity and sodicity. Loaded heavy metals resisted complete removal, even by intensive leaching with EDTA. The case is more pronounced with Pb in soils whose clay content is considerable. Soil suitability to support crops is mediocre at best. Virtual reclamation of soils to reduce soil salinity and sodicity markedly improved suitability for some crops. Suitability findings drawn from this work need to be financially assessed to confirm practical on farm recommendations.Traditional reclamation of sodic and saline soils by gypsum application and subsequent leaching on the field scale may be implemented wherever physically applicable. Several farmers in the area cite their intuitive experience in reclaiming their salt infested soils. The adopted approach is to establish fish ponds for a period of 2 to 3 years, then switch to field crop production.The overriding conclusion of this work is that remediation of soils infested with certain heavy metals is often tedious, expensive, and time consuming. Therefore, preventive measures that minimize possibility of soil loading by heavy metals should be strictly implemented as a first rate priority.
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