Modelling of Evapotranspiration based on Growth Parameters

Abstract

Leaf area index (LAI) and plant height are the basic growth parameters of a plant. The LAI is the index of leaf area that actively contributes to the surface heat and vapor transfer. It is generally the upper sunlit portion of dense canopy. As the LAI and plant height increase the crop evapotranspiration also increases. But after a stage of plant it begins to decrease because of leaf senesce. The leaf area was measured with the help of an electronic laser leaf area meter. A relationship was developed between cumulative blackgram evapotranspiration (ETCM) and LAI. The different models were fitted for obtaining the best model. It was observed that the exponential model gives the best results. The coefficient of determination for exponential model was found to be 0.9881. The exponential model was also found better to represent the relationship between ETCM and plant height.