河西内陆灌区春小麦、玉米膜上灌水技术和地膜覆盖效应试验

2003 年和 2004 年在甘肃省张掖市甘州区二十里堡乡七号村进行了膜上灌条件下的覆膜春小麦和玉米的灌水技术及地膜覆盖效应的试验研究。结果表明地膜覆盖具有明显的增温保墒效应,在作物苗期增温效应尤为显著。覆膜农田地表下 5cm、10 cm、15 cm、20 cm 和 25 cm 在 8:00,14:00 和 18:00 三个时刻,苗期平均地温比露地玉米分别高 3.3 ℃,2.9 ℃,3.2 ℃,2.2 ℃和 2.1 ℃。在灌溉定额和畦长相同的条件下,春小麦整个生育期内,单宽流量为 1.3L/(m·s),在膜宽为 1.25 m的畦田内水流推进速度是露地畦灌的 1.64 倍,并且不会发生冲苗冲埂现象。在当地气候条件、土壤质地和作物栽培方式下,覆膜春小麦、玉米在全生育期内较当地露地节水灌溉系统的灌溉量(4 800m3/hm2和 9 000 m3/hm2)分别节水 2 000～2 400 m3/hm2和 4 000～4 500 m3/hm2,产量分别提高了 10 %～20 %和12 %～45 %。

Irrigation technique and the effect of mulch cover on spring wheat and maize in the Hexi inland irrigation district of Gansu province

According experiment results from 2003 to 2004 in the seventh village of twentith countryside in Zhangye city of Gansu province, it showed that the film-plastic-covering had the obvious effect of improving soil temperature and conserving soil water content, especially in the stage of seedling. Under the surface of film-plastic-covering maize field at 5 cm, 10 cm, 15 cm, 20 cm and 25 cm , the average soil temperature was higher about 3.3 ℃ , 2.9 ℃ , 3.2 ℃ , 2.2 ℃ and 2.1 ℃ than bare maize field in the period of seedling. Under the same condition of irrigation-quota and the length of farmland, the velocity of watering under the single width-flow of 1.3L/s·m was 1.64 times on the farmland width of 1.25m film-plastic-covering and it could not destroy the border and the seedling. Under the local condition of soil characteristics, climate and the system of crop planting, plastic-sheet-covered spring wheat and maize saved water about 2000～2 400 m3/hm2 and 4 000～4 500 m3/hm2 in the whole growth period under the conventional irrigation regime system on 4 800 m3/hm2 and 9 000 m3/hm2 and the corresponding field yield improved by 10 %～20 % and 12 %～45 %.