【摘要】 利用植物茎流计,测定了塔里木沙漠公路塔中段乔木状沙拐枣茎干液流变化及耗水特性。结果表明3株乔木状沙拐枣在一个生长季内的日平均耗水量为4 183.4 g;在现行的灌溉管理条件下,4~10月3株基径为3.6,3.1,1.9 cm的乔木状沙拐枣日平均耗水量分别为6 203.5,4 829.1,1 517.5 g;7月份是耗水量最大的季节。乔木状沙拐枣液流日变化呈单峰曲线型,并随环境因子的变化有所波动;液流高峰值出现在12:00~15:00,最小值出现在0:00~3:00,夜间仍保持较高的液流速率。乔木状沙拐枣液流速率与基径呈正相关关系,在6月底,3株基径为3.6,3.1,2.1 cm的乔木状沙拐枣日耗水量分别为9 521.2,5 803.1 g/d和1 818.8 g/d。不同天气条件下沙拐枣日平均率日耗水量的排列顺序为:小雨<阴天<浮尘<沙尘暴<多云<晴天。干旱的环境条件和较为充足的水分供应是耗水量大的一个重要原因。更多还原

【Abstract】 In this paper,the sap flow in stems of Calligonum arborescens in the shelterbelts along the Tarim Desert Highway in hinterland of the Taklimakan Desert is measured with the stem-sap meters.The result reveals that the average daily water consumption of Calligonum arborescens is 4 183.38 g in growth season.Under the current irrigation and management conditions,the average daily water consumptions of three stems of Calligonum arborescens with diameters of 3.6 cm,3.1 cm and 1.9 cm are 6 203.5 g,4 829.1 g and 1 517.5 g respectively during the period from April to October.The maximum daily water consumption occurs in July.The daily variation curves of sap flow in stems of Calligonum arborescens Litv.are unimodal and fluctuate with the change of environmental factors.The maximum and minimum values of sap flow in stems occur at 12:00～15:00 and 0:00～3:00,respectively,and the speed rate of sap flow in stems is high at midnight.The maximum and minimum values of sap flow in a stem of Calligonum arborescens Litv.with basal diameter of 3.1 cm are(1 277) g/h and 0 respectively during the period from April to August,and the sap flow in stems varies in a range of 0～100 g/h at night.There is a positive correlation between the sap flow velocities in stems and the basal diameters.Under different weather conditions,the average stem sap flow rate is in an order of raining < cloudy < floating dust < overcast < sand storm < sunshine.Sap flow in stems is not affected by soil moisture content.It is considered that the extremely arid environment and the relative enough water supply are the main factors resulting in high water consumption.更多还原