摘要
应用Flow32-1K包裹式热平衡液流仪,对毛乌素沙地沙柳不同径级枝条液流进行长期监测,同步观测试验样地气象变化,分析沙柳枝条液流变化规律并建立与环境因子关系模型。结果表明:(1)沙柳枝条随着径级的增加液流日变化从宽峰曲线到明显的单峰曲线,并且液流速率呈增大趋势;天气条件对液流影响较大,雨天液流速率波动较剧烈,呈明显的多峰曲线;晴天时液流速率变化呈明显的双峰曲线,雨天沙柳枝条液流速率及日液流量均比晴天低,随着径级增大,晴天和雨天日累计液流量差值逐渐变大。(2)液流速率与地表温度、大气温度、饱和水汽压差、太阳辐射和风速呈极显著正相关关系,与空气相对湿度呈极显著负相关关系。(3)雨天环境因子中饱和水汽压差和空气相对湿度对液流速率的影响较大,拟合结果平均R2在0.8以上;晴天太阳辐射强度是控制沙柳枝条液流速率的重要因子,拟合结果平均R~2在0.85以上。通过对沙柳枝条液流速率进行监测,分析沙柳群落的蒸腾消耗特征,为沙地水资源合理利用与群落结构优化调控提供数据支撑。
The sap flow pattern of Salix psammophila branches with different diameters was monitored long-term in the Mu Us Sand using a Flow32-1K wrapped heat balance sap flow meter.Additionally,the relationship between the sap flow of S.psammophila branches and the meteorological changes of the experimental plots was explored.With the increase in the diameter grade of branches,the diurnal variation of sap flow changed from a broad peak curve to an apparent single peak curve,and the sap flow rate showed an increasing trend.Weather conditions substantially influence sap flow,and the fluctuation of the sap flow rate on rainy days was severe,showing an obvious multi-peak curve.Otherwise,the change in the liquid flow rate on sunny days showed an evident bimodal curve.The mean sap flow rate on rainy days was lower than that on sunny days.With the increase in the diameter grade of branches,the difference of the cumulative sap flow rate between sunny days and rainy days gradually increased.Additionally,the sap flow rate showed a significant positive correlation with surface temperature,atmospheric temperature,saturated water vapor pressure,solar radiation,and wind speed,and it was negatively correlated with air relative humidity.On rainy days,saturated water vapor pressure and relative air humidity had a substantial influence on the sap flow rate.However,on sunny days,solar radiation was an important influence factor on sap flow rate.Based on the monitoring of the sap flow rate of branches and the transpiration consumption characteristics of the S.psammophila community,our study informs the rational utilization of water resources and the optimal control of community structure of S.psammophila.
作者
洪光宇
王晓江
刘果厚
张雷
高孝威
李卓凡
刘铁山
刘辰明
李梓豪
HONG Guangyu;WANG Xiaojiang;LIU Guohou;ZHANG Lei;GAO Xiaowei;LI Zhuofan;LIU Tieshan;LIU Chenming;LI Zihao(College of Grassland,Resources and Environment,Inner Mongolia Agricultural University,Hohhot 010011,Inner Mongolia,China;Inner Mongolia Forestry Research Institute,Hohhot 010010,Inner Mongolia,China)
出处
《干旱区研究》
CSCD
北大核心
2021年第3期794-801,共8页
Arid Zone Research
基金
内蒙古科技重大专项(2019ZD007,201601061)
内蒙古自治区自然科学基金项目(2019MS03036,2018MS03036)
国家自然科学基金项目(31960284)共同资助。
