蓄水坑灌下苹果树茎流速率日变化及其影响因子的研究

通过热扩散技术对苹果树茎流速率的测定来研究蓄水坑灌不同灌水处理(处理1:灌水上下限为田间持水量的100%和70%,处理2:灌水上下限为田间持水量的90%和60%,处理3:灌水上下限为田间持水量的80%和50%)以及地面灌溉(处理4)下苹果树茎流速率日变化规律,分析了系统水势及气象因子对茎流速率的影响。结果表明,不同灌水处理下茎流速率在各生育期的日变化趋势基本相同,均为先增大后减小。通过与地面灌溉对比分析得出蓄水坑灌下处理2是相对合理的灌水方案。影响因子方面,叶水势与茎流速率呈负相关,土-叶水势梯度与茎流速率呈正相关,并通过回归分析建立了茎流速率与太阳辐射、大气温度和大气相对湿度之间的回归方程。

Daily Variation of Stem Flow Rate of Apple Tree and Influence Factors Under Water Storage Pit Irrigation

The experiment uses thermal diffusion technique to measure the apple tree stem flow rate to study the daily change rule of apple tree stem flow rate under different treatments, including three water storage pit irrigation treatments, in which the upper and lower limits is 70% and 100%, 60% and 90%, 50% and 80%, respectively, and the surface irrigation treatment.And the effects of water system and meteorological factors on the stem flow rate are also analyzed.The results show that daily variation of the stem flow rate under different irrigation treatment in different growth period has the same trend, namely first increasing then decreasing.Through the analysis of the differences between different processing treatments, it is found that the second water storage pit irrigation treatment is a relatively reasonable irrigation scheme.With regard to the influencing factors, the leaf water potential is negatively correlated with the stem flow rate, the soil-flow rate is positively correlated to the stem and leaf water potential gradient.Through regression analysis, the regression equation among the stem flow rate and the solar radiation, air temperature and air relative humidity is established.