Effects of different mulching patterns on soil temperature, moisture water and yield of spring maize in Weibei Highland

In order to improve rainfall utilization efficiency and increase water availability for crops in dry farming area, a field experiment was conducted in 2007-2010 at Heyang Dryland Farming Experimental Station in Shaanxi province of China to determine the effect of different ridge and furrow with mulching cultivation patterns on soil water, soil temperature, yield of spring maize, and economic returns. The ridges were covered with common plastic film in all treatments, while different furrows were mulched with common plastic film, biodegradable film, corn straw, liquid film and uncovering, respectively. The flat plot without mulch was used as the control. The results obtained in a four-year experiment showed that, at the seedling stage of maize, the average temperature in 5-25 cm soil layer under common plastic film and biodegradable film were 2.4℃ and 2.1℃ higher than that of the control respectively. In contrast, the temperature under corn straw covering was 1.7℃ lower than that of the control. Besides, the different rainwater harvesting treatments could improve soil moisture in the early growth of maize. There was no difference in the soil moisture level between corn straw, liquid film, uncovering and the control during the middle and late growth of maize. However, the soil moisture of common plastic film and biodegradable film in deep soil layer were lower than that of the control. Compared with the control, the 4-year average maize yield with biodegradable film, common plastic film, and corn straw mulching significantly increased by 35.2%, 34.7% and 33.6%, and the average water use efficiency increased by 30.6%, 30.2% and 28.6%, respectively. The total net income with corn straw mulching was the highest, followed by biodegradable film mulching, and the total net income increased by 3 299 and 2 752 Yuan/hm2 respectively, compared to the control. It was concluded that when the ridges were covered with common plastic film, the furrows was mulched with biodegradable film or straw, not only the soil water and temperature conditions were improved, but also the maize yield and net income were increased. Therefore, these two treatments are considered as efficient for maize production in Weibei Highland area.