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塔里木沙漠公路防护林生长于极端干旱的塔克拉玛干沙漠中,防护林植物的蒸腾耗水和灌溉管理是防护林可持续的核心问题.利用茎流计测定了塔里木沙漠公路塔中段3种防护林植物的茎干液流,研究了防护林植物茎干液流规律、水分状况和现行灌溉模式下植物的耗水量,探讨了防护林灌溉管理中的节水问题.对茎干液流测定结果表明,防护林植物茎干液流具有明显昼夜节律性,液流的高峰值出现在白天10:00~15:00,最小值出现在00:00~03:00,夜间也保持较小的液流.3株直径1.9~2.0cm乔木状沙拐枣(Calligonum arborescens)、多枝柽柳(Tamarix ramosissima)、梭梭(Haloxylon ammodendron)在生长季的日平均茎干液流速率分别为67.2,77.05和61.54g·h-1;茎干液流受环境因子影响而波动,太阳辐射、风速、气温、相对湿度和植物茎干液流有显著相关性.8年生沙拐枣、柽柳、梭梭植株年耗水量分别为1937.80,1253.39和1026.96kg,日平均耗水量分别为9.69,6.27和5.13kg.滴灌条件下,防护林带内土壤含水量在各个月份变化不大,土壤含水量充足,防护林植物清晨和午后水势变化反映出其水分状况良好.如对现行灌溉管理模式进行优化,实现防护性能与水资源节约的有机结合,防护林还存在一定的节水空间.
Tarim Desert Highway Shelterbelt grows in the extreme arid Taklamakan Desert.The transpiration water consumption and irrigation management of shelterbelts are the core issues in the sustainable development of shelterbelt.The stem flow of three shelterbelts in the middle Tarim Desert Highway , Studied the law of stem-tree flow, water status and current water consumption of plant in protection forest, and discussed the water-saving problem in the irrigation management of shelterbelts.The result of stem flow showed that the stem-flow of protection forest plant had Significant circadian rhythms, the peak value of the flow appeared in the day 10: 00 ~ 15: 00, the minimum occurred in 00: 00 ~ 03: 00, also kept a small flow at night .3 strains of 1.9 ~ 2.0cm in diameter trees The average daily stem-flow rates of Calligonum arborescens, Tamarix ramosissima and Haloxylon ammodendron in the growing season were 67.2, 77.05 and 61.54 g · h-1 respectively. Flow affected by environmental factors and fluctuations, solar radiation, wind speed, temperature, relative humidity and plant stem flow was significantly related to 8 years of Calligonum, Tamarix, Haloxylon ammodendron water consumption were 1937.80,1253 .39 and 1026.96kg, the average daily water consumption was 9.69,6.27 and 5.13kg. Under drip irrigation, soil moisture in shelterbelt changed little in each month, and soil moisture content was sufficient, and the change of water potential in shelterbelts morning and afternoon Its moisture is in good condition.If the current irrigation management mode is optimized to achieve the organic combination of protection performance and water conservation, shelterbelts still have some water saving space.