元谋干热河谷旱地玉米-油菜不同覆盖保水栽培措施的水分效应

Water effect of different covering retention cultivation measures on corn-cole in Yuanmou dry and hot valley dryland

为了探究一年两熟作物的不同保水栽培措施的水分效应,在元谋干热河谷地区进行玉米-油菜田间试验,比较了不同保水栽培措施的土壤贮水量、保蓄水度、耗水强度、经济效益等指标,以揭示不同保水栽培措施的水分利用机理.结果表明：秸秆、地膜覆盖都具有一定的保水效果,尤其以地膜秸秆两元覆盖效果最为突出;土壤贮水、保蓄水度呈现处理Ⅰ＞处理Ⅱ＞处理Ⅲ＞处理Ⅳ的趋势,且0～30 cm的变化＞30～60 cm的变化＞60～100 cm的变化,即0～30 cm土层水分变化较为活跃,30～60 cm土层水分变化相对稳定,60～100 cm土层水分变化最为稳定;覆盖方式不同保水栽培措施的经济效益与对照（处理Ⅰ）相比,增收在11.39％～26.50％,表明覆盖保水栽培对于提高干热河谷区的农业生产效率是切实可行的.

In order to explore the water effects of different covering retention cultivation measures about two crops a year, typical dryland corn-cole field trials were done to compare the soil water storage, degree of water storage, water consumption intensity, and other economic indicators of different covering retention cultivation measures. The study aimed at revealing different water use mechanisms of covering retention cultivation measures. The results showed that, straw and mulching had some effect on water retention, especially the effect of straw-mulch cover was the most prominent. The soil water storage and degree of water protection showed treatment Ⅰ 〉 treatment Ⅱ 〉 treatment Ⅲ 〉 treatment IV, and the 0-30 cm change〉 30-60 cm change〉 60-100 cm change, showing that 0-30 cm soil moisture change more active, 30-60 cm soil moisture change relatively stable, 60-100 cm soil moisture change the most stable. Economic benefits of different water cultivation measures increased 11.39%-26.50%, showing the covering retention water cultivation was feasible to improve the agricultural production efficiency of dry hot valley.