The changing laws of the diurnal evapo transpiration and soil evaporation between plan ts in the winter wheat field of the North China Plain

The changing laws and affecting factors 0f the diurnal evapotranspiration and aoil evaporation between plants in the winter wheat field are studied in this paper．The results show that the ratio Of evapo ration tO evapotranspiration is the most from seeding tO recovering an d it is the least from tasseling to grain·-filling；the ratio of evapo ration tO evapotranspiration in the winter wheat field is about 31．4％ during the whole periods；the equation of the relationship between the rati0 of evaporation to evapotranspiration(E／ET)and LAJ is E／ET=0．3693×(LAI)^-0.7493(R² =0．8236)．