Soil Quality Evaluation Using GIS Techniques: A Case Study of North Nile Delta, Egypt.

The present work aimed at using GIS spatial analysis tools to map soil quality (SQ) of the cultivated lands for sustainable agricultural development. The study covers an area of about 2306.43 km 2 in the north Nile Delta of Egypt (31°08' 38" to 31° 36' 15.53" N and 31°01' 16.67" to 31° 54' 40.37" E). Thirty-two surface soil samples (0 – 30 cm) were collected and analyzed for their chemical and physical properties. Within GIS platform, raster layers for SQ indicators were generated using the inverse distance weight (IDW) technique. They were normalized using fuzzy membership functions, and finally the fuzzified layers were integrated using the geometric mean algorithm to develop the SQ maps. Results revealed that soils of very high and high qualities covered nearly 32% of the total area. Soils of moderate quality occupied 18% of the total area, while soils of very low and low qualities occupied 37% of the total area. To improve soil quality status, it is recommended to cultivate salt-tolerant crops, apply leaching fraction, and construct sufficient drainage systems, adopt organic and gypsum application, and operate tillage using appropriate equipment at proper time. The proposed model would help in decision making for sustainable agronomic practices in the studied area.