Recharge estimation using remotely sensed evapotranspiration in an irrigated catchment in southeast Australia

Abstract

Abstract:Reliable estimates of groundwater recharge are required for the sustainable management of surface and ground water resources in semi-arid regions particularly in irrigated regions. In this study, groundwater recharge was estimated for an irrigated catchment in southeast Australia using a semi-distributed hydrological model (SWAT). The model was calibrated under the dry climatic conditions for the period from August 2002 to July 2003 using flow and remotely sensed evapotranspiration (ET). The model was able to simulate observed monthly drain flow and spatially distributed remotely sensed ET. Recharge tended to be higher for irrigated land covers, such as perennial pasture, than for non-irrigated land. On average, the estimated annual catchment recharge ranged between 147 and 289 mm which represented about 40% of the total rainfall and irrigation inputs. The optimized soil parameters indirectly reflected flow bypassing the soil matrix that could be responsible for this substantial amount of recharge. Overall, the estimated recharge was much more than that previously estimated for the wetter years.

Calibration of Spatially Distributed Hydrological Processes and Model Parameters in SWAT Using Remote Sensing Data and an Auto-Calibration Procedure: A Case Study in a Vietnamese River Basin

“…Some local differences occur unavoidably due to the inaccuracy of the various mathematical expressions used to compute a complex hydrological process such as ET. Remote sensing ET values reflect more the real world conditions as they are based on observations [33][34][35]42]. The agreement between SWAT and remote sensing data was expressed by means of the correlation coefficient and the bias.…”

“…For this particular study, a total number of 15 plant and soil parameters were pre-selected according to their sensitivity to the evolution of ET and LAI. The selection of these parameters was based on detailed reviews and analyses on SWAT parameters carried out before by various authors (e.g., [16,42,43,54,59]). …”

“…can be found in [54]. A similar list of parameters was also suggested by [16,42,59]. Calibration of ET is less common, because this dataset is usually not available.…”

Multi-variable SWAT model calibration with remotely sensed evapotranspiration and observed flow

“…Remotely sensed evapotranspiration (ET) has important spatial and temporal resolution and can be used to estimate soil water balance related parameters, such as soil moisture (ALLEN et al, 2007;GITHUI;SELLE;THAYALAKUMARAN, 2012;IMMERZEEL;DROOGERS, 2008). Recently, some studies have integrated remote sensing data into the calibration of distributed hydrological models (GITHUI; SELLE; THAYALAKUMARAN, 2012;MUTHUWATTA;BOOIJ;RIENTJES, 2009) obtaining streamflow prediction performance improvement (KUNNATH-POOVAKKA et al, 2016;WANDERS et al, 2014;ZHANG et al, 2009).…”

“…Recently, some studies have integrated remote sensing data into the calibration of distributed hydrological models (GITHUI; SELLE; THAYALAKUMARAN, 2012;MUTHUWATTA;BOOIJ;RIENTJES, 2009) obtaining streamflow prediction performance improvement (KUNNATH-POOVAKKA et al, 2016;WANDERS et al, 2014;ZHANG et al, 2009). Rajib, Merwade and Yu (2016) calibrated the SWAT model using streamflow and soil moisture simultaneously, and compared it with the conventional calibration (streamflow only).…”