The land zonation for applying drip irrigation system by evaluation of water and soil characteristics (Case study: Babol and Babolsar counties)

The accessible water resources would not be able to meet the different needs erelong. Inevitably this would cause to search for newer lands for irrigation. According to the water resources’ limitation and the necessity of using the pressurized irrigation systems to gain the optimum use of the available water resources, it would be necessary to determine suitable lands for agriculture and pressurized irrigation. The land suitability (LS) classification is defined as the determination and classification of specific land areas according to their suitability for the desire use. The parametric evaluation system (PES) makes it possible to have the best decision by ranking different effective factors on the goal parameter. By considering that the underlying management and proper planning and optimum use of resources requires accurate and detailed information of the area of interest, in this context, Geographical information system with the ability of spatial analysis capabilities, analyzing and integrating the map information, tables and reports, can play a great role in achieving the set goals.
At the current study the zonation of priority of applying drip irrigation systems (DIS) within Babol and Babolsar counties is done by parametric evaluation of some of soil physicochemical characteristics and water chemical characteristics by geographic information system (GIS). The soil characteristics were Texture (T), Depth (D), Slope (S), Acidity (pH), and Electrical Conductivity of soil saturation extract (ECe). The water characteristics were Chloride (Cl), Boron (B), Electrical Conductivity (EC), Sodium Adsorption Ratio (SAR) and Residual Sodium Carbonate (RSC). These data were obtain from Jahad e Keshavarzi (agriculture) organization of Mazandaran.
The evaluation of the soil parametric index (SPI) indicated that the most area (approximately 90% of the total studied area (TSA)) is “suitable”. The most area for water parametric index (WPI) (approximately 75% of the total studied area) was “currently not suitable”. The evaluation of WPI’s sub-indexes indicated that the most limitation levels (severe and very severe levels) were related to residual sodium carbonate (RSC) index (approximately 90% of TSA). It was 9.4%, 8.5%, 0% and 0% for chlorine (Cl), electrical conductivity (EC), boron (B) and sodium adsorption ratio (SAR) sub-indexes respectively.
According to the results to apply DIS at the studied area, the prevention considerations (to prevent emitters from clogging due to high levels of RSC), like pickling would be necessary. In addition using drippers which have less sensibility to clogging is suggested, in order to preventing drippers clogging at very severe damage possibility locations.