Examination of the effects of different test times and flow rates on the infiltration characteristics of vertisol soils

In this study, the effects of flow rates and infiltration times in tests were investigated on infiltration properties of vertisol soils. Depending on the formation of the cracks, the infiltration characteristics changes were investigated by infiltrayon tests made at different times and using different flow rates. For this purpose, spring, summer and autumn seasons and in the cracks left by the closed and open conditions, infiltration tests were made using different flow rates. The standard deviations of the infiltration coefficients "b" and "n", which reflect the hydraulic properties of the soils, are 0.0671 and 0.1169, respectively, which are not affected by changes in the a and K values from the time of the tests or from changes in soil moisture content. The lowest basic intake rate was determined as 2.81 cm h-1 in the fall and this value was 7.3 cm h-1 in the summer, where cracks were not covered with plaster. It can be said that the average basal water uptake rate of the Vertisol soils of Harran Plain is around 4.5-5.0 cm h-1. According to the results obtained from the tests made at different times, the irrigation schemes created significant results for each other. As many researchers have noted, it has been understood that the generalization of the results obtained from infiltration tests on vertisol soil is not correct. The most suitable infiltration test period should be at the level of moisture at the end of the RAW in the soil, and at 20-40% above the permenant wilting point (PWP) of the soil moisture content. In this case, it can be said that in Harran plain is the most suitable period for infiltration tests to be used in irrigation planning in vertisol soil, spring seasons.