覆膜种植方式对东祁连山区苜蓿草地土壤温度和水分的影响

Effects of Different Film-Mulching Planting Patterns on Soil Temperature and Water Moisture of Alfalfa Grassland in Eastern Qilian Mountain Area

高寒地区耐寒苜蓿品种和适宜栽培技术的缺乏,严重阻碍着该区域旱作苜蓿和草地畜牧业的发展。于东祁连山甘肃天祝高寒牧区通过设置平膜全覆、垄沟覆膜、垄沟覆膜+覆土和垄沟(不覆膜)4种种植方式,探讨不同种植方式对苜蓿草地土壤温度和水分的影响,旨在为祁连山高寒区苜蓿的高产栽培提供理论依据。结果表明,高寒区平膜全覆种植方式的增温效果最佳,其次为垄沟覆膜、垄沟,垄沟覆膜+覆土最弱。地膜提温主要在苜蓿生长初期(5月)和生长期(6-7月),主要集中在0~15cm的浅层土壤。5-9月平膜全覆0~25cm土层白天平均温度为19.83℃,分别比垄沟覆膜、垄沟覆膜+覆土和垄沟处理同期同层高出1.85℃、3.04℃和2.98℃。垄沟覆膜处理下土壤含水量最大,其土壤含水量比平膜全覆、垄沟覆膜+覆土和垄沟处理的土壤含水量高4.3%~14.5%,4.2%~13.8%和14.3%~24.8%。平膜全覆对天祝高寒区苜蓿生长在温度上的贡献最大,而垄沟覆膜在水分上的贡献最大。

The lack of cold-resistance alfalfa varieties and appropriate cultivation techniques has seriously hindered the development of dry land alfalfa and grassland husbandry in alpine area.In order to provide a theoretical basis for cultivation of high-yielding alfalfa,four planting method treatments included A：Film mulching parallel to the ground,B：film mulching on ridge and furrow,C：film mulching on ridge and furrow ＋ soil cover,and D：ridge and furrow planting patterns were designed on Tianzhu alpine pastoral located on Eastern Qilian mountain area by testing soil temperature and moisture.The results showed that the warming effect of treatment A was best,then treatment B,treatment C was the weakest.Soil temperature of film treatment increased in the early growth stage（May）and growing stage（June and July）.Effects on temperature mainly concentrated in the soil from 0 to 15 cm.The average daytime temperature of treatment A in soil layer from 0 to 25 cm from May to September was 19.83 ℃,which was 1.85℃,3.04℃,and 2.98℃ higher than treatment of B,C,and D,respectively.Soil moisture of treatment B was the largest,it was higher than A,C and D for 4.3%to 14.5%,4.2%to 13.8% and 14.3%to 24.8%,respectively.Treatment A had a great contribution to the temperature of alfalfa grown in Tianzhu alpine area,while treatment B was on soil moisture.