The effect of adding different levels of NPK using GIS systems in some areas of Dhi Qar and Wasit

Abstract

The study was conducted in the governorates of Wasit and Dhi Qar, with two sites selected in each. 
Wasit Governorate included Al-Hay District and Al-Muwafaqiyah Sub-district, while Dhi Qar 
Governorate included Al-Qal'ah District and Al-Fajr District. The soils in each site varied in some of 
their physical and chemical properties. Only nitrogen and phosphate fertilizers were applied to all the 
study fields. Samples were taken from the fields before planting for the required analyses. 
Geographic Information Systems (GIS) were used to predict certain soil fertility parameters and 
produce a fertility map for each area. Based on fertility assessment and using the standard 
multiplication method, soil properties affecting crop fertility were identified. This method, adapted 
from the Sys method for soil assessment, was used to determine the soil properties that influence 
fertility for crop cultivation. Furthermore, the final fertility map was correlated with wheat yield for 
each area, and a database of soil properties was built with minimal effort and cost. Therefore, the 
study results indicated the existence of three soil types in terms of fertility assessment in the study 
areas. The highly fertile and infertile soil types were not observed in the study areas. The fertile soil 
type comprised 30% of the soil in Al-Hayy, 30% in Al-Muwafaqiyah, and 20% in Al-Qalaa, but was 
not observed in Al-Fajr. This type is characterized by its high NPK content. The moderately fertile 
soil type comprised 40% of the soil in Al-Hayy, 30% in Al-Muwafaqiyah, 50% in Al-Qalaa, and 60% 
in Al-Fajr. This type is characterized by its good NPK content. The low-fertility soil type comprised 
30% of the soil in Al-Hayy, 40% in Al-Muwafaqiyah, 30% in Al-Qalaa, and 40% in Al-Fajr. This 
type is characterized by its medium NPK content.