荒漠绿洲区临泽小枣及枣农复合系统需水规律研究

Water requirement regularity in Linze jujube (Ziziphus jujuba Mill. var. inermis Rehd. cv. Linze jujube) and jujube/crop complex systems in Linze oasis

在大田环境下, 通过建造2 m×2 m×2 m的封底观测池, 利用水量平衡法, 研究了甘肃省河西走廊中部黑河中游绿洲临泽小枣、春小麦、紫花苜蓿单作及临泽小枣/春小麦、临泽小枣/紫花苜蓿间作复合系统的需水规律。结果表明, 内部绿洲和边缘绿洲的临泽小枣从根系开始活动到落叶的需水量分别为497.2 mm和859.2 mm, 春小麦从播种到收获需水量分别为447.9 mm 和809.9 mm, 紫花苜蓿从返青到霜降需水量分别为583.7 mm 和945.7 mm, 临泽小枣/春小麦复合系统需水量分别为647.7 mm 和1 009.7 mm, 临泽小枣/紫花苜蓿复合系统需水量分别为980.3 mm 和1 342.3 mm。边缘绿洲临泽小枣/春小麦复合系统增加的需水量为枣树需水量的17.5%, 小麦需水量的24.7%; 临泽小枣/紫花苜蓿复合系统增加的需水量为枣树需水量的56.2%, 紫花苜蓿需水量的41.9%。内部绿洲临泽小枣春季（4月25日～5月31日）需水量为84.6 mm, 夏季（6月1日～8月31日）为351.3 mm, 秋季（9月1日～10月5日）为61.3 mm; 7月份需水强度最大, 为4.8 mm·d^-1, 6月份次之, 为4.3 mm·d^-1, 生长期平均需水强度为3.1 mm·d^-1。临泽小枣灌溉应保证4个关键水, 即花前水、果实膨大水、丰果水和越冬水, 灌水定额为1 200 m^3·hm^-2。

The water balance method was used to study water requirement regularity of Linze jujube, spring wheat, alfalfa monoculture system and Linze jujube/spring wheat, Linze jujube/alfalfa complex system in an 8 m^3 observation pool （2 m × 2 m × 2 m ） under field environment. The results show that water requirements in the inner and edge oases for Linze jujube from root-activation to leaf-shedding stage are respectively 497.2 mm and 859.2 mm, spring wheat from sowing to harvesting stage are 447.9 mm and 809.9 mm and those for alfalfa from greening to frosting are 583.7 mm and 945.7 mm. Water requirements in the inner and edge oases for Linze jujube/spring wheat complex system are respectively 647.7 mm and 1 009.7 mm and those for Linze jujube/alfalfa complex system are 980.3 mm and 1 342.3 mm. In the edge oasis, the increased water require-ment of Linze jujube/spring wheat system is 17.5% and 24.7% of Linze jujube and spring wheat water requirement respec-tively. That of Linze jujube/alfalfa system is 56.2% and 41.9% of Linze jujube and alfalfa respectively. In the inner oasis, water requirement for Linze jujube is 84.6 mm in spring （April 25～May 31）, 351.3 mm in summer （Jun. 1～Aug. 31） and 61.3 mm in au-tumn （Sep. 1～Oct. 5）. For the growth period, water requirement is maximum （4.8 mm·d^-1） in July and 4.3 mm·d^-1 in June, with an average water requirement of 3.1 mm·d^-1. Linze jujube irrigation should be ensured in the four key periods of before flowering, fruit swelling, accelerated fruit growth and over-wintering. Irrigation amounts for these periods of growth should be 1 200 m^3·hm^-2.