Soil moisture analysis is widely used in numerous practical cases, from weather forecasts to precise agriculture. Recently, availability of moisture data increased due to the rapid development of satellite image processing. However, satellite retrievals mostly provide low-resolution surface data. In this study, we attempt to retrieve surface soil moisture on the field scale using a decomposition algorithm. Furthermore, we add a mathematical model based on Richards equation to evaluate soil moisture in the root zone. To combine the results of both models, we employ a nudging data assimilation technique. Also, a dynamical variation of the method is proposed which makes it more adaptive to the soil type and provides improvement to modeling results. Two types of numerical experiments are conducted. Simulation results show reasonably good convergence with the measurements. The model performs with average correlation of 0.58 on the whole root zone, reaching 0.85 on top soil layers.
This paper deals with a nonlinear soil moisture transport problem, solved with addition of satellite observed soil moisture. The satellite data are assimilated into the model using Newtonian nudging method. Evaluation is done by the triple collocation method, which involves three independent data sources: model results, ground stations and ERA5 climatic data. The results testify that model results are nearly as accurate as the ground station measurements.
In this paper we study a mathematical model of soil moisture transport with variable porosity. The problem is set for the case of highly concentrated solute spilled onto soil surface. We investigate the way solute transfer, adsorption of contaminant by soil particles and variable porosity influence infiltration of solute into the soil profile. For that purpose, two models are used: a classical one and the one with consideration of mentioned factors. By comparing the results of both models, we established that high concentration of solute causes moisture transport to transpire more slowly, and the pollutant to remain on the soil surface for longer time. Numerical results indicate that porosity can vary considerably under the conditions of intensive contamination with salts.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.