The effect of cultivation type, irrigation method and underground water fluctuations on changes in some soil physicochemical characteristics (Case study: Darab Fars)

Sustainable land management is of great importance as one of the components of global sustainable development. In order to achieve sustainable management, planning is necessary, because accurate assessment of the land and reducing the destructive effects of the soil provide a safe environment for production. Knowing the changes and evolutions of land use over a period of time is very important to show the change process over time. . Considering the trend of droughts and destructions in Darab city, the aim of this research is land use based on knowing the capacity and allocating it to the best and most profitable type of use.

In this research, changes in solutes, well ring data and irrigation methods were investigated. Sampling was done from 36 points. In this research, the type of irrigation including four types of drip, strip, rain and strip irrigation was identified and based on that seven factors pH, EC, OC, TNV, N, P2O5, K2O were measured. In the next step, the depth of the well and the volume of the annual water harvest were determined, and based on that, the changes in soil solutes were investigated. Pearson correlation tests were used to check the relationship between variables.

In rain irrigation, pH and EC were standard, TNV was higher than standard, OC, P2O5 , K2O and N were lower than standard. In drip irrigation, the pH in one sample was higher than 8 and one sample was lower than 7, the EC value was higher than the standard in two cases and the TNV value was lower than the standard in 5 samples. OC, N and K2O were below standard in all cases, P2O5 was standard in 5 cases. In strip irrigation, soil pH was between 7 and 8 in all cases, EC was standard in 7 cases, T.N.V was lower than standard in 7 cases. The amount of soil O.C, N, K2O and P2O5 was lower than the standard value in all cases. In strip drip irrigation, the pH of the soil was lower than the standard in one case. The value of EC was lower than the standard value in one case, the value of TNV, OC, N and K2O was lower than the standard in all samples, and the value of P2O5 was standard in one case. The correlation coefficient between the annual water harvesting volume and soil changes showed that, in the tested lands, the relationship between the water harvesting volume with O.C, pH, EC, S.P, T.N.V was negative and the correlation with P2O5, K2O, N was positive. The correlation coefficient between the depth of the well and the fluctuation of soil changes showed that the relationship between the volume of water withdrawal with O.C, pH, EC, SP, TNV was negative and the correlation with N, P2O5, K2O was positive.