北京山区油松的耗水规律

为了探究北京山区常绿树的耗水规律,利用大型称重式蒸渗仪于2010年对北京西山地区油松蒸腾进行连续高精度的观测,分析油松蒸腾的动态变化,同时结合气象因子的观测数据,分析蒸腾强度与气象因子的相关性,从而定量得到各因子对蒸腾的影响程度。结果表明:油松晴天蒸腾日变化呈单峰曲线趋势,在中午时刻出现最大值,与太阳辐射和气温变化趋势保持一致;阴雨天表现为多峰曲线趋势。在各气象因子中,蒸腾强度(Ti)与大气温度(Ta)、大气相对湿度(RH)、冠层净辐射(Rn)和饱和水汽压差(VPD)的相关性较好,其相关方程为Ti=2.228-0.07Ta-0.032RH-0.002Rn+1.108VPD。

Water consumption of Pinus tabuliformis in Beijing Mountain Area

In order to explore the evapotranspiration of evergreen trees in Beijing Mountainou Area,the dynamic change of Pinus tabuliformis transpiration in the West Mountain Area of Beijing was continuously and high-precision measured in June 2010 using large-scale weighing lysimeter.Combined with the observational data of meteorological factors,the correlation between transpiration intensity and meteorological factors was analyzed.The results showed that： In sunny days,diurnal variation of transpiration of Pinus tabulaeformis showed a single-peak curve trend and the maximum was found at noon,which was in accordance with the solar radiation intensity and the temperature.But in rainy days,it showed the multi-peak curve trend.Transpiration intensity（Ti） was significantly related to atmospheric temperature（Ta）,relativeair humidity（RH）,canopy net radiation（Rn） and vapor pressure deficit（VPD）,the regression equation was Ti=2.228-0.07Ta-0.032RH-0.002Rn＋1.108VPD.