干旱年份地膜覆盖模式对春小麦土壤水分和产量的影响

在西北半干旱雨养条件下,采取不同地膜覆盖方式,研究了春小麦地膜覆盖的水分效应。结果显示,覆膜可显著提高土壤表层（0-20cm）墒情,但在拔节后土壤深层墒情覆膜明显不如露地。从200cm土体全生育期平均水分状况来看,地膜覆盖的耗水量比对照少;6种模式中,甘谷模式和甘肃模式的秋覆膜的土壤水分状况明显优于露地;覆膜的春小麦产量高于露地（平均增产率44.45%,增产711.45kg·hm^-2）,且秋覆膜的平均产量略高于春覆膜。试验表明,覆膜春小麦在更干旱土壤上获得更高产量的水分保障和增产机制是能有效利用深层土壤水分,同时把深层的水分输送到表层。

Effects of Plastic Film Mulching Patterns on Soil Moisture and Spring Wheat Yields in Drought Years

An experiment was conducted to study effect of different plastic film mulching on soil moisture of spring wheat and further to explore approaches of increasing wheat yield and improve water use efficiency.The effect of plastic film mulching with three methods on soil moisture were investigated under semi-arid rain fed conditions in the Northwest of China.The results showed that the plastic film mulching could increase the moisture content of soil surface layer（0-20cm） significantly,however,after jointing stage,the moisture content of soil surface layer was obviously lower than the open field treatments.The water consumption of the mulched land was generally less than the control,viewed by the average moisture condition during the whole period of growth of soil body（2m）.The moisture conditions of Gansu and Gansu Models among the six were markedly higher than that of open ground.The yield from the land mulched with plastic mulch was higher than that from the open ground,with an average increase of 44.45% and by 711.45kg·ha^-1.The yield from the land mulched in autumn was higher than that from the land mulched in spring.Water assured and the stimulation mechanism of higher yields were the effective use of deep soil moisture and the ability to transport the deep moisture to surface in spring mulching under the more arid soil.