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以白皮松、侧柏、桧柏和沙地柏为试材,采用盆栽称重方法,研究了水汽压亏缺与叶片气孔导度对苗木蒸腾耗水的影响,以期测得苗木的蒸腾耗水特性。结果表明:在土壤水分充足的情况下,苗木的水分利用率总体呈下降趋势,苗木日平均水分利用率表现为白皮松(3.01μmol·mmol~(-1))>侧柏(2.62μmol·mmol~(-1))>沙地柏(2.57μmol·mmol~(-1))>桧柏(2.35μmol·mmol~(-1))。3种典型天气中,苗木蒸腾耗水为晴天>半晴天>阴天。苗木昼夜蒸腾耗水排序为白皮松(0.030g·cm-2·d~(-1))>沙地柏(0.026g·cm-2·d~(-1))>侧柏(0.018g·cm-2·d~(-1))>桧柏(0.008g·cm-2·d~(-1))。苗木的蒸腾耗水与水汽压亏缺、叶片气孔导度呈正相关关系,受其影响最大的是白皮松。研究结果可为科学评价园林绿化树种耗水状况、提高园林绿地水分利用率提供参考依据。
Taking Pinus bungeana, Platycladus orientalis, Sabina przewalskii and Sabina vulgaris as test materials, we studied the effects of vapor pressure deficit and leaf stomatal conductance on transpiration water consumption of seedlings by pot weighing method in order to determine the transpiration water consumption characteristics of seedlings. The results showed that under the condition of sufficient soil moisture, the water use efficiency of seedlings showed a general downward trend. The average daily water use efficiency of seedlings showed that the average water use efficiency of B. bungeana (3.01μmol · mmol -1)> Arborvitae (2.62μmol · mmol ~ (-1)> Sabina vulgaris (2.57μmol · mmol -1)> cypress (2.35μmol · mmol -1). Three kinds of typical weather, seedlings transpiration water for sunny> sunny day> cloudy. The diurnal and transpiration water consumption of seedlings was ranked as follows: Pinus bungeana (0.030g · cm -2 · d -1)> Sabina vulgaris (0.026g · cm -2 · d -1)> Arborvitae (0.018g · cm -2 · d -1)> cypress (0.008g · cm -2 · d -1). Transpiration water consumption of seedlings and water vapor pressure deficit, leaf stomatal conductance was positively correlated, the most affected by the white bark pine. The results can provide a reference for scientifically evaluating the water consumption status of landscape tree species and increasing the water use efficiency of landscape green space.