期刊名称:Universal Journal of Environmental Research and Technology
电子版ISSN:2249-0256
出版年度:2011
卷号:1
期号:4
出版社:Euresian Publications
摘要:Precise estimation of evapotranspiration obtained by multiplying crop coefficient to reference evapotranspiration using readily available climatic data. Penman-Monteith equation is adopted world wide as the most reliable and accurate method for computing reference evapotranspiration. The Food and Agriculture Organization (FAO) presented crop coefficient for estimation of evapotranspiration of different crops based on Penman-Monteith equation. The crop coefficient curves can be developed by plotting the ratios of crop evapotranspiration and reference evapotranspiration with respect to time. The crop coefficient curves were developed for mustard (Brassica juncea) by FAO-56 curve method and modified FAO-56 curve method. The FAO-56 curve method underestimates mustard evapotranspiration by 16.80 per cent. Therefore, FAO-56 curve method does not appear to predict mustard evapotranspiration accurately. The modified FAO-56 curve method underestimates mustard evapotranspiration only by 8.33 per cent. Therefore, performance of modified FAO-56 curve method was found better than FAO-56 curve method for estimation of mustard evapotranspiration
关键词:Crop evapotanspiration; crop coefficient; reference evpotranspiration; and FAO curve .