Differences in hydrologic response across the rain-snow transition in the southern Sierra Nevada were studied in eight headwater catchments – the Kings River Experimental Watersheds – using continuous precipitation, snowpack, and streamflow measurements. The annual runoff ratio (discharge divided by precipitation) increased about 0.1 per 300 m of mean catchment elevation over the range 1,800-2,...

In this study, yield-water and profit function was used to obtain water demand function in agriculture sector. The results showed that the ratio of actual to potential Evapotranspiration had positive, significant effecton the ratio of actual to potential yield for wheat and barley. Also, square ratio of actual to potential Evapotranspiration had negative, significant relationship. After estimat...

The energy hypothesis predicts that, in regions of roughly equal area, energy flux per unit of area should be the prime determinant of species richness. In the case of plants, primary production represents realized energy capture. Potential evapotranspiration is a measure of community energy use and it is related to terrestrial primary productivity. The best correlate of the latter on regional ...

Three methods including the Penman-Monteith (PM), Priestley-Taylor (PT), and 1963 Penman equation (PE) for calculating daily reference evapotranspiration (ETo) were evaluated in the Maritime region of Canada with the data collected from 2004 to 2007. An automatically operated meteorological station located on the Potato Research Centre, Agriculture and Agri-Food Canada, Fredericton, New Brunswi...

In the Brazilian semi-arid region, the intensification of agriculture results in a change of natural vegetation by irrigated crops. To quantify the contrast between these two ecosystems, the large-scale values of water productivity components were modelled in Petrolina (PE) and Juazeiro (BA) municipalities. The SAFER (Simple Algorithm For Evapotranspiration Retrieving) algorithm was used to acq...

coriandrum sativum l. is one of the most important plants compared to the other herbs and medicinal plants as a planted covered area in kermanshah province. for a suitable irrigation management programming, the awareness of crop coefficient and water requirement in different plant stages is essential. the ratio of actual evapotranspiration to reference crop evapotranspiration is defined as crop...

Evapotranspiration is a major loss flux of the water balance in arid and semi-arid areas. The estimation of actual evapotranspiration has significance for hydrological and environmental purposes. The Surface Energy Balance System (SEBS) algorithm was applied to estimate actual evapotranspiration in the Qaidam Basin and its eight hydrological sub-regions, Northwest China. There were 3,036 cloud-...

Eucalyptus species are widely planted for reforestation in subtropical China. However, the effects of Eucalyptus plantations on the regional water use remain poorly understood. In an age sequence of 2-, 4- and 6-year-old Eucalyptus plantations, the tree water use and soil evaporation were examined by linking model estimations and field observations. Results showed that annual evapotranspiration...

A distributed model for simulating the land surface hydrological processes in the Heihe river basin was developed and validated on the basis of considering the physical mechanism of hydrological cycle and the artificial system of water utilization in the basin. Modeling approach of every component process was introduced from 2 aspects, i.e., water cycle and energy cycle. The hydrological proces...