Estimation of volumetric soil water content over the Liudaogou river basin of the Loess Plateau using the SWEST method with spatial and temporal variability

Monitoring soil moisture with spatial and temporal distribution is in big demand in arid and semi-arid regions. In Loess Plateau in China, where soil erosion is a major issue, information about soil water content helps in the planning of regional water resources and vegetation restoration for the prevention of erosion. In this study, we have developed the SWEST (soil water estimation from surface temperature) method by integrating well-known relationships among surface temperature, evapotranspiration and soil water content. An advantage of the proposed SWEST method is that it can estimate soil water content for the location of a water source of evapotranspiration, where there would be a near-surface for bare soil and the root zone for well vegetated surfaces. A verification study conducted at Liudaogou River Basin of the Loess Plateau, China, indicated the method could estimate soil water content accurately, with an estimation error of about 2.6% of the total volume of soil. Application of the method to satellite thermal imaging successfully presented the applicability of the SWEST method to estimate soil water content with spatial and temporal variability.

[1]  M. Shao,et al.  Optimization of plant coverage in relation to water balance in the Loess Plateau of China , 2012 .

[2]  R. Ziemer.  Evaporation and transpiration , 1979 .

[3]  Bin Zhang,et al.  Effect of vegetation restoration on soil and water erosion and nutrient losses of a severely eroded clayey Plinthudult in southeastern China , 2004 .

[4]  Reiji Kimura,et al.  Estimation of moisture availability over the Liudaogou river basin of the Loess Plateau using new indices with surface temperature , 2007 .

[5]  Pute Wu,et al.  Soil moisture variability along transects over a well-developed gully in the Loess Plateau, China , 2011 .

[6]  B. Fu,et al.  The effect of land cover/vegetation on soil water dynamic in the hilly area of the loess plateau, China , 2007 .

[7]  M. S. Moran,et al.  The scaling characteristics of remotely-sensed variables for sparsely-vegetated heterogeneous landscapes , 1997 .

[8]  Reiji Kimura,et al.  Evapotranspiration over the Grassland Field in the Liudaogou Basin of the Loess Plateau, China , 2006 .

[9]  Duli Zhao,et al.  Modeling vegetation coverage and soil erosion in the Loess Plateau Area of China , 2006 .

[10]  L. S. Pereira,et al.  Crop evapotranspiration : guidelines for computing crop water requirements , 1998 .

[11]  Assefa M. Melesse,et al.  A Coupled Remote Sensing and Simplified Surface Energy Balance Approach to Estimate Actual Evapotranspiration from Irrigated Fields , 2007, Sensors (Basel, Switzerland).

[12]  William P. Kustas,et al.  Use of remote sensing for evapotranspiration monitoring over land surfaces , 1996 .

[13]  J. Hupy.  Influence of vegetation cover and crust type on wind-blown sediment in a semi-arid climate , 2004 .

[14]  Heat balance and soil moisture in the Loess plateau, China , 2004 .