Abstract:To evaluate the applicability of farmland irrigation and drainage in southern Xinjiang, adopting the experiment of water supplied by Markov bottle, of fixed disc infiltrometer, of cotton indoor seeding and growth, the effect of farmland irrigation and drainage on infiltration characteristics of the soil water at point source and non-point source, cotton emergence rate and growth was studied. The experiment results showed that during the test of soil water point source infiltration, the horizontal migration at different salinity irrigation water infiltration was more obvious than the longitudinal direction. When drainage salinity was over 2g/L, the soil water content values in the horizontal direction showed a significant downward trend with the increasing of salinity. During the test of soil water non-point source infiltration, the amount of soil water infiltration decreased with the increasing salinity at the same water head. And the amount significantly decreased with the decrease of water head. According to steady-state non-point source infiltration, soil saturated hydraulic conductivity Ks increased first and then decreased after different salinity irrigation, but the model parameters λc changed oppositely, when drainage salinity was at 2g/L, Ks and λc reached inflection point, and the effect was more obvious with the higher salinity. The cotton had a normal growth when water salinity was below 3g/L, while there was a obvious damage to the cotton emergence rate when it was at 5g/L. There was a low effect on cotton seeding growth when the salinity was below 4g/L, however, cotton growing was slowed significantly when the salinity was over 4g/L.
