油橄榄开花时期的茎流量动态变化及其与气象因子的关系

在掌握开花时期油橄榄树干茎流动态变化特征的基础上，探索气象因子与树干茎流的关系。结果表明，开花时期油橄榄晴天树干茎流日变化呈单峰形趋势，峰值出现在12:00-15:00，雨天树干茎流日变化呈双峰形趋势，晴天树干茎流量比雨天提高了15.8%。油橄榄开花时期树茎流量随太阳辐射强度的增大而呈降低的趋势，当太阳辐射最高值出现在12:00-15:00，与茎流出现峰值相同，太阳辐射与树茎流量间关系呈极显著相关关系，而茎流值会随空气相对湿度的增加逐渐减低，当空气相对湿度＞20.9%时树干茎流呈下降趋势,空气相对湿度与油橄榄树茎流量两者间呈负相关，而空气温度和风速与树茎流量呈正相关关系，虽然空气温度与茎流量与相关性较低，但当空气温度＞25.7 ℃时树干茎流会小幅度下降。通过分析气象因子与油橄榄茎流速率的关系，构建多元线性回归模型，在小时尺度上，太阳总辐射对油橄榄树干茎流速率的影响最大R²=0.655，对开花时期油橄榄树茎流速率的影响气象因子为太阳辐射＞风速＞空气湿度（负相关）＞空气温度。在油橄榄开花时期可根据此模型推导出油橄榄树的潜在茎流量，以此为油橄榄开花时提出合理的节水补灌时间，对后期增加挂果量和提高产量有重要意义。

Dynamic Changes of the Stem Sap Flow of Olive During Flowering Period and the Relationships with Meteorological Factors

On the basis of understanding the dynamic characteristics of stem sap flow (SSF) of olive during flowering period,we explored the relationship between meteorological factors and the SSF.The results showed that the diurnal variation of SSF in sunny days showed a single peak curve,peak value occurred in the afternoon from 12:00-15:00; in rainy days,it showed a double peak curve.Compared to rainy days,the SSF increased by 15.8% on sunny days.The highest value of solar radiation occurred during 12:00-15:00,the same as time when the peak value of SSF appeared.The relationship between solar radiation and SSF showed a very significant correlation,and the SSF value would gradually decrease with the increase of air relative humidity,when the relative humidity of air>20.9%,the SSF showed a downward trend,and the relative humidity of air and the SSF showed a negative correlation,while the relationship between the SSF and temperature and wind speed showed positive correlation.Though the correlation between SSF and temperature was low,the SSF would decrease slightly when the air temperature was more than 25.7 ℃.A multiple linear regression model was constructed by analyzing the relationship between meteorological factors and SSF.At the hourly scale,the impact of total solar radiation on SSF was the most significant (R²=0.655),and impacts of the meteorological factors affecting SSF were in the order of solar radiation>wind speed>air humidity (negative correlation)>air temperature.The potential SSF can be deduced according to this model,so as to put forward a reasonable water-saving supplementary irrigation time for olive flowering,which is of great significance to increase the fruit setting and yield in the later stage.