Uniformity is an important parameter in operation of center pivot irrigation system, and evaporation drift loss(EDLs)is a significant factor affecting water and fertilizer utilization efficiency of sprinkler irrigation system. In this study, the relationship between flow rate and operational range of diaphragm metering pump connected with a center pivot of 0.15 MPa pressure was tested. Field experiments were conducted to evaluate uniformity of water and fertilizer application and EDLs. The results indicated that RMSE of injection when connected with center pivot was 9.0% and a small relative error(RE)was achieved under in the operational range of 60%-100%(RE≤5.6%), while a substantially higher RE(RE≥13.3%)was got in the range of 20%-40%. When the pivot rotational speed was 100% of the full speed, the modified Heermann-Hein uniformity coefficients of radial irrigation and fertilizer application were equalbasically, with variation ranges of 80%-85% and 78%-86%, respectively, which were all less than the uniformity of radial solution concentration ranged in the range 96%-99%. There was no significant difference in uniformity of fertilizer solution application and solution concentration between different fertilizer types and concentrations. When the wind speed was less than 2 m/s, EDLs were ranged in 1.5%-10.1%(average 5.1%)with center pivot.
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