Comparative study of estimated and simulated reference evapotranspiration of black gram and wheat crops in mollisol of Uttrakhand

摘要

Evapotranspiration is the combination of soil evaporation and crop transpiration. Weather parameters, crop characters, management and environmental factors affect evapotranspiration. Reference evapotranspiration (ET0) is an important agrometeorological parameter for climatological and hydrological studies. The reference evapotranspiration concept has been gaining significant acceptance by scientists throughout the world since its introduction. ETQ can also be estimated from pan evaporation. Pans haveproved their practical value and have been used successfully to estimate ETQ by observing the water loss from the pan and using empirical coefficients to relate pan evaporation (FAO-24 pan method). The rate of evapotranspiration is usually expressed inmillimetres per unit time. Estimates of evapotranspiration from cropped land surfaces are vital for agricultural water management. ET0 values estimated or calculated at different locations or in different seasons are comparable as they refer to the evapotranspiration from the same reference surface. ETQ is an agro-climatic parameter and can be computed form the weather data. ETQ express evaporating power of the atmosphere at specific location and time (Allen et. ah, 1989,). Through crop models, it became possible to simulate a living plant through the mathematical and conceptual relationship which governs its growth in the soil atmospheric continuum (Thornley 1976). Crop models can help researchers, policymakers, and farmers to make correct decisions on crop management practices, and also for marketing strategies and food security of a country with a deterministic view on the import-export market.