الفهرس 
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Abstract
Dakahlia Governorate is one of the most important agricultural governorates in the Nile-Delta of Egypt. It covers an area of about 431 km2. It is located between latitudes 30◦ 48’ 13.20” to 30◦ 59’ 46.65” N and longitudes 31◦ 19’ 57.52” to 31◦ 41’ 29.22” E. Elevation varies from 1 to 5 m above sea level. For that purpose, 17 geo-referenced soil profiles were randomly dug throughout the studied area and sampled based on their development. Fifty one soil samples were collected from these profiles and analyzed for their physical, chemical, and fertility properties. Water samples were also collected from irrigation, drainage and mixed water from both irrigation and drainage canals. Land evaluation was carried out using the Agriculture Land Evaluation System (ASLE), which is a GIS based land evaluation system. The results could be summarized as follows : The obtained results indicated that the majority of soils in the studied area were Clay, which had a significant influence on the soil physical properties such as the saturation percentage (SP), bulk density (BD) and total porosity. The average values of SP, BD, and total porosity were about 71%, 1.08 g cm-3, and 59%; respectively. Chemical properties of the studied soils revealed that sodium was the prevalent cation in the soil solution followed by magnesium, calcium and Potassiumions. Their average concentrations were about 0.93, 0.22, 0.19and 0.01 cmol kg-1 soil, respectively. In the contrary, chlorides were the dominant anions followed by bicarbonates and sulfates. Their average values were about 0.81, 0.20, and 0.34 cmol kg-1 soil; respectively. where soil pH was about 7.95 in average. where the EC values varied from 0.41 to 4.65 dS m-1 with an average value of 1.88 dS m-1. Cation exchange capacity (CEC) was highly affected by the fine-texture and it value was about 50.0 cmol kg-1 soil in average. Exchangeable sodium percentage (ESP) was about 4.17% in average; The average values of available NPK were about 124, 5.40, and 310 ppm; respectively. Total nitrogen and organic carbon in the studied soils were very low about (about 0.26 and 0.47% in average, respectively). As a result, the C/N ratio was about 2: 1 in average. The concentrations of cations and anions in collected water samples took a similar trend as those in soil solution. EC values of water sample were increased from 0.51 dSm-1 in irrigation water to 0.83 dSm-1 in drainage water, and 1.05 dSm-1 in mixed water. The sodium adsorption ratio (SAR) was about 4.07% in average and the residual sodium carbonates (RSC) had negative values( -1.57 meq l-1 in average). Conclusions Land capability and suitability in the Nile Delta, Egyptwere effectively evaluated using the ASLE. Soils in the studied area were fit into two capability classes. These classes are fair and poor. Differed appropriate soil selected crops between very suitable and appropriate medium. It can reduce the impediments to productivity of the soil for crops in the study area through the use of fertility and soil management practices appropriate. In summary, the land in the province of Dakahlia a promising future for agricultural reclamation and cultivation projects, where most of soil limitations of crop production is permanent and can be improved through the implementation of sound management practices.