Measuring and modeling evapotranspiration of a Populus euphratica forest in northwestern China

Environmental Controls on Evapotranspiration and Its Components in a Qinghai Spruce Forest in the Qilian Mountains

“…For modeling, the SW model and the clumped model and their improved forms have been widely used due to their suitable physical mechanisms. Researchers nowadays mainly focus on optimizing the structures of the dual- or multi-source models [ 20 , 22 , 100 , 101 , 102 ], but these models incorporate a large number of parameters, some of which are difficult to parameterize [ 31 ]. The FAO-56 dual crop coefficient model is an indirect method for calculating ET from reference crop ET and crop coefficients.…”

“…These methods were reviewed by Kool et al [ 14 ] and classified into two categories: models and measurements. The commonly used models were the Shuttleworth–Wallace model [ 19 ] and its improved structures [ 20 , 21 , 22 , 23 , 24 , 25 ], the clumped model [ 26 , 27 ], the FAO-56 dual crop coefficient model [ 28 , 29 , 30 ] and other improved dual-source models [ 31 , 32 , 33 ], while measurements were mainly eddy covariance techniques [ 34 , 35 , 36 , 37 , 38 ] and Bowen ratio systems [ 39 , 40 , 41 ] (acquiring ET), stable isotopes [ 42 , 43 , 44 , 45 ] (acquiring E s or T ), sap flow meters [ 46 , 47 , 48 , 49 ] (acquiring T ), microlysimeters [ 50 , 51 , 52 ] (acquiring E s ) and water collection tanks [ 53 , 54 ] (acquiring E i ). Among these methods, the modeling approach has the advantage of its applicability over a wide range of time scales and can be applied to the spatial scale of an entire ecosystem [ 55 , 56 ], but these models always require complex parameterizations and still require validation.…”