Zhang Han-dan, Wei Wei, Chen Li-ding, Yu Yang, Yang Lei, Jia Fu-yan
Huan Jing Ke Xue. 2015 Jan;36(1):349-56.
Transpiration is one of the major processes of water consumption. It is significant for nutrients transportation, plant development, drought stress alleviation and micro-climate amelioration. In this study, the artificially planted Chinese pine (Pinus tabuliformis) was selected as an example to explore its transpiration characteristics, water-use strategies and the adaptability of the living environment in a typical loess hilly area of China. The results showed that: the sap flow rates of Chinese pine varied obviously in different seasons. The minimum sap flow rate occurred in April, followed by October, September and August, which was 0.024, 0.057, 0.062 and 0.071 mL x (cm2 x min)(-1), respectively. The rule of the diurnal variation of sap flow rate was regular, higher in daytime than at night. The flow rate was low during nighttime, but not zero. In rainfall events, the proportion of sap flow during nighttime was significantly increased, which was 3.9 times of that on sunny days, with 31.8% decrease in daytime. Chinese pine had great adaptability to unexpected climates. The variation trend of flow rate in the clod was similar to that on rainy days. The sap flow velocity was in great relevance with meteorological factors, with a declining order of solar radiation, vapor pressure deficit, relative humidity, and atmospheric temperature.
蒸腾作用是水分消耗的主要过程之一。它对于养分运输、植物生长发育、缓解干旱胁迫以及改善微气候具有重要意义。本研究以人工种植的油松（Pinus tabuliformis）为例，探讨其在我国典型黄土丘陵区的蒸腾特性、水分利用策略及对生存环境的适应性。结果表明：油松的液流速率在不同季节差异明显。液流速率最小值出现在4月，其次是10月、9月和8月，分别为0.024、0.057、0.062和0.071 mL×(cm²×min)⁻¹。液流速率的日变化规律较为规则，白天高于夜间。夜间液流速率较低，但不为零。在降雨事件中，夜间液流所占比例显著增加，是晴天的3.9倍，白天则下降31.8%。油松对突发气候具有较强的适应性。阴天时液流速率变化趋势与雨天相似。液流速度与气象因子密切相关，影响程度由大到小依次为太阳辐射、水汽压差、相对湿度和大气温度。
