Analysis of Energy Balance Characteristics and Meteorological Influence Factors of Winter Wheat Farmland in North China Plain
The variation characteristics of energy balance components of farmland ecosystem are closely related to water cycle processes,water resources management and agricultural sustainable develop-ment.Based on the data of 2020-2021 eddy covariance system and meteorological elements from Anyang National Climate Observatory,the diurnal and monthly variations of net radiation,latent heat flux,sensi-ble heat flux and soil heat flux at different growth stages of winter wheat farmland are analyzed,and the main meteorological elements affecting the energy balance components of farmland ecosystem in North China Plain are clarified.The results show that:(1)The trends of diurnal variations in energy fluxes are basically the same in different growing stages of winter wheat,showing a single-peak conic curve.During the daytime,the latent heat flux is less than the sensible heat flux in the seedling and overwintering sta-ges,but significantly greater than the sensible heat flux in the jointing and milking stages.The soil heat flux is small in the whole growing season of winter wheat,and can decline to the smallest in the overwin-tering stage.(2)For monthly variation,the net radiation and latent heat flux shows a trend of decreasing first and then increasing overall,with latent heat flux being the smallest at 0.39 MJ·m-2·d-1 in January and the largest at 9.38 MJ·m-2·d-1 in May.The sensible heat flux is opposite to that of latent heat flux.During the whole growing period of winter wheat,soil heat flux is the lowest in December and the highest in May.As winter wheat grows,the percentage of latent heat flux to net radiation tends to de-crease and then increase,while the sensible heat flux shows an opposite trend.(3)On the hourly scale,the latent heat flux,sensible heat flux and soil heat flux are highly and positively correlated to air temper-ature,saturated vapor pressure deficit and wind speed,but highly and negatively correlated to relative humidity and soil moisture.On the daily scale,except sensible heat flux,other fluxes have significant positive correlations with air temperature,saturated vapor pressure deficit and soil temperature,but have no insignificant correlation with relative humidity.
winter wheatenergy balance characteristicsinfluence factorNorth China Plain
万方数据
维普
