Water saving irigation and moving zinc on paddy land of Red river delta

Abstract

    This study was developed on growing rice area of Red River delta in Tien Lu, Hung Yen with four rice cultivation seasons from 2015 to 2016 with two experimental formulas including flood irrigation (FI) and water saving irrigation (WSI). The results showed that FI affect signyficantly moving zinc, deeply water level in a long-time causes to decrease Eh, pH and mobile zinc and vice versa. FI on the Red River delta not only consumes lots of irrigation water but also lowers nutrients sulphate and mobile zinc in the paddy soil, reducing 1.37±0.03mg/100grams soil (gs) and 0.5684± 0.0022mg/100gs respectively. However, status SO4 2- and Zn2+ are improved on applying WSI with increasing 0.18±0.02mgSO4 2-/100gs and slighly reducing 0.0371mgZn2+/100gs each a crop. So that WSI brings many advantages of saving water, increasing Eh, maintaining Zn2+ status and furthermore decreasing toxic from fertilizer in the paddy soil.