The rise in water demand for agriculture, industry, domestic, and environmental needs requires sagacious use of this limited resource. Since agriculture (mainly irrigation) is the major user of water, improving agricultural water management is essential. Efficient agricultural water management requires reliable estimation of crop water requirement (evapotranspiration). Evapotranspiration (ET) i...

in recent decades, neyshabour basin as a semi-arid climate has faced with dramatic increasing of groundwater withdrawal. so, water demand management is important in this basin. in this study, the effects of evapotranspiration and rainfall on groundwater fluctuations have been considered with 22 rain gage and evaporation gage station data during 1973-2006. the average amount of rainfall and evap...

abstract evapotranspiration (et) is one of the most important components of the water balance, it is also one of the most difficult to measure. despite the importance of et, methods to obtain values of et are still limited. conventional methods are very local, ranging from point to field scale. estimates of the et over the entire area, especially for irrigated areas, are essential, as these can...

A brief history of development of the 1985 Hargreaves equation and its comparison to evapotranspiration ~ET! predicted by the Food and Agricultural Organization of the United Nations ~FAO! Penman-Monteith method are described to provide background and information helpful in selecting an appropriate reference ET equation under various data situations. Early efforts in irrigation water requiremen...

Reference crop evapotranspiration (ET o), used to determine actual crop evapotranspiration, is often estimated from pan evaporation (EP) data. However, uncertainties in the relationship between ET o and EP often result in unreliable estimate of crop evapotranspiration. This study investigated the relationship between measured and estimated crop evapotranspirations, ET m and ET e, respectively, ...

The paper presents a method for precise estimation of evapotranspiration of selected turfgrass species. The evapotranspiration functions, whose domains are only two relatively easy to measure parameters, were developed separately for each of the grass species. Those parameters are the temperature and the volumetric moisture of soil at the depth of 2.5 cm. Evapotranspiration has the character of...

Reference Evapotranspiration (ET0) is a basic parameter for determination of irrigation program. It is one of the most important factors in water resources management and considers as a requirement for every irrigation and drainage plans. Because of the spatial variations of ET0, it is necessary to use from intrapolation methods in order to estimation of this parameter in regional studie. Using...