Nile water pollution and technical efficiency of crop production in Egypt: an assessment using spatial and non-parametric modelling

Agriculture is considered one of the vital activities in Egypt; it consumes about 83 % of the Egyptian Nile water quota. This activity is becoming negatively affected by water pollution causing negative repercussion on land productivity and subsequently food security. This paper assesses the water quality for agriculture along the mainstream of the Nile in Egypt through spatial distributions modelling of total dissolved solids (TDS), using spatial statistical analysis. The study’s sample frame consists of 78 sampling points collected in February 2008 and located on the Nile mainstream and its two branches, Rosetta and Damietta. Exploratory spatial data analysis is carried out on the TDS, followed by plotting and modelling the experimental semi-variogram. Then, cross validation is executed in order to determine the best fitting model. Finally, surface mapping is generated by performing spatial interpolation, using kriging technique. The generated surface map shows that the TDS levels increase from Upper to Lower Egypt, exceeds the standard limit in Beni-Suef and Rosetta branch. In fact, high levels of TDS are known to have a negative effect on Egyptian agriculture through harmfully affecting the soil and consequently the crop yields. Therefore, an analysis of the effect of water pollution on technical efficiency of crop production is conducted using a non-parametric mathematical programming approach to frontier estimation. The results of this estimation indicated that the TDS is overutilized in all governorates except Aswan.