The Effect of Irrigation Management and Cultivation pattern on Soil Quality Indices (Case study: Agriculture fields of Semnan)

Soil quality, as a factor, is changing due to variation of soil inherent characteristics and the type of management practices on the soil. Integrated Quality Index and Nemero Quality Index were applied to evaluate the influence of land use types, different irrigation managements, and types of cultivated products on the soil quality in Semnan region.  After describing 13 soil profiles in five selected crop fields and orchards, soil samples were taken from different horizons and 14 properties efective on the soil quality were determined and the proposed indecs were calculated. The results showed that the quality of top layers of agricultural lands are classified as II and III degree, while the top layer and sublayer of garden lands are classified as IV degree due to lack of profile evolution, low organic carbon and high salinity. The highest average soil quality indices were assigned to alfalfa (flood irrigation) with 0.67; followed by barley (sprinkler irrigation) with 0.59, olive orchard (drip irrigation) with 0.39 and olive orchard (flood irrigation) with 0.32. This finding indicates the positive effect of cover crops on land reclamation of Semnan region. The effect of irrigation system on soil quality indices did not show any significant difference among them, as the flood irrigation in alfalfa and olive farms showed the highest and the lowest soil quality indecs, respectively. Also, there was no significant difference in soil quality of olive orchards under drip irrigation vs. flood irrigation. Soil quality indecs make opportunity to agricultural managers to choose appropriate management strategies and monitoring the changes in the soil quality.