Interaction effects of organic fertilizers and legume plants on the infiltration parameters in a soil of semiarid region

Soils of arid and semi-arid regions are poor in organic matter, and therefore the soil structure in these areas is weak and as a result, infiltration rate in the soil is low. The aim of this study was to investigate the effect of combined application of organic fertilizers and leguminous plants growth on physical and hydraulic parameters in a selected soil from semi-arid region including bulk density, particle density, total porosity, accumulated infiltration, infiltration rate and also Philip, Kostiakove and modified Kostiakove equations parameters. Factorial experiment was based on randomized complete block design in which the first factor was three types of organic fertilizers including caw manure compost, caw manure vermicompost and poultry manure, second factor was used rate of fertilizers in three levels including zero, 75 and 150 kg N/ ha and the third factor was, three treatments of legume cultivation including without cultivation, chickpea and lentil cultivation in three replicats. A total of experimental plots were planted in one of the farms around Ardabil in the year 2016. Then seeds of legume plants were cultivated with recommended intensity of Ardabil Province Agricultural Research Center. The research results of study showed that among three types of used fertilizers, poultry manure due to high organic carbon and among plant cultivars lentil plant has the most significant positive and significant effect on the physical properties of soil and infiltration rate parameters in soil. Also, by increasing the amount of fertilizer, most of the physical properties of the soil are affected positively and the shape of the cumulative infiltration curve was transmitted to the top, also the highest final infiltration rate was obtained in poultry manure (highest fertilizer level) by 0.24 cm / min. The highest value of soil profile transmisivity in the Philip model was obtained as 0.2 cm/min at the highest usede rate of poultry manure and 0.19 cm/min at the highest used rate of organic fertilizer and lentil cultivation. Soil sorptivity coefficient in the Philip model was significantly increased from 1.1 cm min-0.5 in the control (without cultivation) to 1.15 and 1.4 cm min-0.5 in chickpea and lentil treatments, respectively. In total, the combined use of organic fertilizers and legume plants improved infiltration parameters of soil in the semiarid region