Comprehensive effects of different mulching materials on winter wheat productions in Weibei highland

In order to search for the comprehensive effects of different mulching on winter wheat production. Three years experimental results showed that when the land with winter wheat was covered with water osmosis plastic film, straw, normal plastic film mulching during growth period, they had particularly effect of distinct increased yield, the effects of all three methods were: significant increase in yield and soil water contents except for normal plastic film mulching which allows the upper layer of soil water keeping for a long time. The mulching could also increase soil temperature, reduce temperature difference between day and night, avoide precipitation to impact on ground directly, keep better soil structure. Compared normal plastic film and straw mulching, winter wheat yield with water-osmosis plastic film mulching increased by 43.1% and 40.4%. Straw mulching remarkably increased soil organic matter and fertility. Water-osmosis plastic film had effect of increase in temperature. When air temperature was more than 35℃, water-osmosis plastic film had function of reduced extreme temperature. Long term mulching promote excessive mineralization of soil organic nitrogen and nitrate nitrogen which could be leached very easily during latter stage of winter wheat growth.