The Effect of Brackish Ice Mulching on Soil Salinity Content and Crop Emergence in Man-Made, Raised Bed on Saline Soils

Resumo

Brackish ice is mulched on saline soil of a man-made, raised bed in the west coast of the China’s Bohai Bay to improve soil conditions (water and salinity) for crop growth. Experiment plots in the raised bed were exposed to two treatments: (1) no application of brackish ice and (2) 4000 m³/ha of brackish ice mulched onto the soil. The melted processes of brackish ice had two features: higher salinity and lower volume of meltice water in the initial stage; lower salinity and higher volume of melt-ice water in the final stage. The treatment with brackish ice mulching increased soil moisture at all soil depth compared to the control treatment without brackish ice during the melted stage of brackish ice (from February 19). In the later stages of brackish ice melting, the brackish ice mulching reduced (Student’s t-test; p < 0.05) soil salinity of the 20, 40 and 60 cm zone and but increased soil salinity of the 80 cm zone in the raised bed compared to the control treatment without brackish ice. Brackish ice mulching increased emergence rate and plant height of maize compared to the control treatment without brackish ice. These results indicated that the mulching of raised beds of saline soil by brackish ice seems to improve soil conditions for growing spring crops in the saline soil with sufficient natural or man-made drainage systems and acceptable reservoir for drainage waters.