不同田间配置对玉豆带状套作系统水分分布及水分利用率的影响

摘要

探讨了1．6m和2．0m带宽不同玉米行距下玉豆带状套作系统共生期水分分布及水分利用率的变化。结果表明：随着玉米行距的增加，地面上玉米叶片空间分布不同，形成窄行部叶面积指数高于宽行，导致土壤水分蒸发、穿透降雨量和土壤水分都表现为玉米行＜玉豆行＜大豆行，玉豆带状套作共生期穿透降雨量分布不均和玉米大豆对土壤水分吸收是造成土壤含水量分布不均的主要因素；两种带宽下带状套作玉米产量和群体产量随玉米行距的增加表现为先增加后持平，在玉米行距为50 cm时，带状套作玉米产量和群体产量最高；两种带宽下玉米行距为50 cm时带状套作水分利用率最大，分别为23．06 kg·hm－2·mm－1和26．60 kg·hm－2·mm－1，总体上较单作提高了38．92％和22．98％；两种带宽下水分当量比分别为1．45～1．66和1．60～1．79，2．0m带宽比1．6m带宽更加有利用于提高农田的水分利用效率，玉米行距在40～50 cm时更能有效提高群体的水分利用效率。%This paper was about the changes in water distribution and water use efficiency in maize rows with 1 .6 m and 2 .0 m width under the maize-soybean strip intercropping systems during the symbiotic period .It was shown that with the increase of maize rows ,spatial distribution of maize leaves on the ground was different .LAI of narrow rows was high-er than that of wide rows ,resulting in soil evaporation ,throughfall ,and soil moisture in the order of maize rows