X‐ray computed tomography imaging of solute movement through ridged and flat plant systems
| Autor: | Siul Ruiz, Tiina Roose, Katherine Williams, Callum Scotson, Simon Duncan |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
geography
geography.geographical_feature_category Materials science fungi 0207 environmental engineering Soil Science Soil science 04 agricultural and veterinary sciences 02 engineering and technology 15. Life on land 6. Clean water Infiltration (hydrology) Ridge Soil water 040103 agronomy & agriculture 0401 agriculture forestry and fisheries Tomography Leaching (agriculture) 020701 environmental engineering Surface water Water content Ponding |
| Zdroj: | European Journal of Soil Science |
| ISSN: | 1365-2389 1351-0754 |
| DOI: | 10.1111/ejss.12985 |
| Popis: | The aim of this investigation was to experimentally compare the movement of a solute through soils with two field-representative surface geometries: ridge and furrow surfaces versus flat surfaces. X-ray computed tomography (XCT) imaging was undertaken to trace the movement of a soluble iodinated contrast medium, here used as an XCT-visible analogue for field-applied solutes, through soil columns with either a ridge and furrow or flat soil surface geometry. In addition to the soil surface geometry, the experimental treatments included the presence or absence of plants and surface water ponding. Experimental results were compared to existing numerical simulations adapted to represent the present experimental column systems. Similar infiltration patterns were observed in imaging results and the numerical simulations for most treatments. The experimental results suggest that plant roots present a significant localized effect to reduce the infiltration depth of solutes, particularly in planted ridges where the infiltration depth of the contrast medium was minimal. There is variability within the results because the number of replicates was limited to three due to the exploratory nature of the study (testing eight different treatments) and the cost and availability of XCT facilities capable of imaging such physically large samples. Discrepancies between the imaged infiltration depth of the solute and the numerical simulations are attributed to variation in plant root distribution and also spatial soil moisture, as measured using resistive soil moisture sensing. The results of this investigation elucidate the nature of solute movement through soil surface geometries, indicating that plant root water uptake can reduce solute infiltration depth, but surface ponding can negate this. These results suggest that soil surface shape, plant age and the timing of solute application with anticipated rainfall could be important considerations for reducing solute leaching and improving solute application efficiency. Highlights: Investigating factors affecting solute infiltration in flat or ridge and furrow soil geometries. X-ray CT imaging traces soluble contrast media movement in soil columns and is compared to modelling. Plant root water uptake can reduce solute infiltration depth, but surface ponding can negate this. Considering soil surface shape, rain and plant age in solute application could reduce leaching. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Plný text