Publicação
Modelling of soil water content and soil salinity with HYDRUS-1D
| Resumo: | Salt-affected soils may result in highly negative impacts on the soils’ functions, limiting the soils’ productivity and ultimately leading to desertification. The area of salt-affected soils is increasing globally as a result of inadequate irrigation practices and of climate change. This work was carried out within the SoilSalAdapt project, which studies the hypothesis that adaptation of soil microbiome to soil salinity may result in increased crop tolerance. The aim of this work was to model the soils’ water content and soil salinity in the three different soils used in the experiment carried out by the project team at the Lincoln University, UK. In experiment, spinach was grown in vases, without fertilization, inside a polytunnel, during two growth cycles. Spinach was irrigated with non-saline water and, at the end of the second cycle, with highly-saline water. In this work, SIMDualKc was used to calculate crop evapotranspiration under standard conditions using the dual crop coefficient method. HYDRUS-1D was used to model the soil water content and electrical conductivity of soil water, integrating water and salinity stresses to obtain the actual crop evapotranspiration. The models resulted in a root mean square error between 0.024 and 0.063 cm3cm-3 for soil water content and between 1.74 and 3.31 dSm-1 for soil salinity. The errors were lower when considering only the first growth cycle. At the end of the second cycle, when saline water was applied, the models underestimated the water content and overestimated the salinity. These larger errors reflect the fact that observed data, which was measured with a TDR, overestimated the soil water content when soil salinity was high. The models obtained in this thesis will allow the simulation of soil salinity under short- and long-term conditions, considering different irrigation managements and future climate conditions, and the estimation of potential productivity losses. |
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| Autores principais: | Antunes, João Francisco dos Santos |
| Assunto: | soil salinity modelling SIMDualKc HYDRUS-1D solo salinidade modelação |
| Ano: | 2023 |
| País: | Portugal |
| Tipo de documento: | dissertação de mestrado |
| Tipo de acesso: | acesso aberto |
| Instituição associada: | Universidade de Lisboa |
| Idioma: | inglês |
| Origem: | Repositório da Universidade de Lisboa |
| Resumo: | Salt-affected soils may result in highly negative impacts on the soils’ functions, limiting the soils’ productivity and ultimately leading to desertification. The area of salt-affected soils is increasing globally as a result of inadequate irrigation practices and of climate change. This work was carried out within the SoilSalAdapt project, which studies the hypothesis that adaptation of soil microbiome to soil salinity may result in increased crop tolerance. The aim of this work was to model the soils’ water content and soil salinity in the three different soils used in the experiment carried out by the project team at the Lincoln University, UK. In experiment, spinach was grown in vases, without fertilization, inside a polytunnel, during two growth cycles. Spinach was irrigated with non-saline water and, at the end of the second cycle, with highly-saline water. In this work, SIMDualKc was used to calculate crop evapotranspiration under standard conditions using the dual crop coefficient method. HYDRUS-1D was used to model the soil water content and electrical conductivity of soil water, integrating water and salinity stresses to obtain the actual crop evapotranspiration. The models resulted in a root mean square error between 0.024 and 0.063 cm3cm-3 for soil water content and between 1.74 and 3.31 dSm-1 for soil salinity. The errors were lower when considering only the first growth cycle. At the end of the second cycle, when saline water was applied, the models underestimated the water content and overestimated the salinity. These larger errors reflect the fact that observed data, which was measured with a TDR, overestimated the soil water content when soil salinity was high. The models obtained in this thesis will allow the simulation of soil salinity under short- and long-term conditions, considering different irrigation managements and future climate conditions, and the estimation of potential productivity losses. |
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