SSS9.1 | Agrogeophysics: understanding soil-plant-water interactions and supporting agricultural management with geophysical methods
Agrogeophysics: understanding soil-plant-water interactions and supporting agricultural management with geophysical methods
Co-organized by BG2
Convener: Sarah Garré | Co-conveners: David O Leary, Alejandro Romero-Ruiz, Ellen Van De VijverECSECS
Orals
| Tue, 25 Apr, 14:00–15:45 (CEST)
 
Room K2
Posters on site
| Attendance Tue, 25 Apr, 16:15–18:00 (CEST)
 
Hall X3
Orals |
Tue, 14:00
Tue, 16:15
Agrogeophysics harnesses geophysical methods such as ground-penetrating radar, electrical imaging, seismic,... from hand-held over drone to satellite-borne, to characterize patterns or processes in the soil-plant continuum of interest for agronomic management. These methods help develop sustainable agricultural practices by providing minimally-invasive, spatially consistent, multi-scale, and temporally-resolved information of processes in agro- ecosystems that is inaccessible by traditional monitoring techniques. The aim of this session is to feature applications of geophysical methods in agricultural research and/or show methodologies to overcome their inherent limitations and challenges. We welcome contributions monitoring soil or plant properties and states revealing information relevant for agricultural management; studies developing and using proximal or remote sensing techniques for mapping or monitoring soil-water-plant interactions; work focused on bridging the scale gap between these multiple techniques; or work investigating pedophysical relationships to better understand laboratory-scale links between sensed properties and soil properties and states of interest. Submissions profiting on data fusion, utilizing innovative modeling tools for interpretation, and demonstrating novel acquisition or processing techniques are encouraged.

Orals: Tue, 25 Apr | Room K2

Chairperson: David O Leary
14:00–14:05
14:05–14:15
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EGU23-16030
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SSS9.1
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solicited
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On-site presentation
Esther Bloem, Robert Barneveld, Dominika Krzeminska, and Jannes Stolte

Norwegian agriculture is challenged by increased production demand and climate change while being faced with tight restrictions to its environmental impact. Due to climate change, an increase in extreme weather events is expected. High intensity rainfall events lead to flooding and water-logged conditions, which have negative impacts on yield and operational conditions related to tillage and transport (trafficability of the soil). Two thirds of Norway's agricultural area is drained to prevent water logging, but at times these drained soils have problems with too high water content, leading to delayed tillage in spring time resulting in lower yields. About 10% of the cultivated land is considered poorly drained.

Saturation and infiltration excess overland flow leads to sheet erosion. Erosion rates often follow a seasonal pattern with the highest soil losses during late autumn and early spring. For most of the total soil loss only a few runoff events are responsible each year. Soil loss from agricultural areas in Norway is not only harmful because of the loss of nutrient rich topsoil, but also because of off-site effects, especially in freshwater systems.

Poorly drained soils are prone to deterioration of its structure. In areas where overland flow concentrates, this may lead to the development of gullies. Ephemeral gullies make up a considerable part of the sediment losses from agricultural areas. In addition, they are shortcuts for sediment transport, forming a connection between the hillslope and the surface water system.

Seasonal saturation excess because of snow melt and rain also leads to high flow rates in Norway’s stream and river network. Flooding problems at the intersection between streams and roads occur even in first order streams.

While many soil conservation and water retention measures complement each other, they sometimes affect each other adversely. Intensification of tile drainage, for example, may reduce sheet and gully erosion risk levels, but will have an adverse effect on peak flow rates and flood risk. Other measures, like buffer zones, serve both purposes. But when, how and under which circumstances water retention and soil conservation measures function remains a complex question.

Understanding the spatio-temporal dynamics of water in the vadose and groundwater zones therefore is a key component of integrated agro-ecological management strategy at low (farm) and high (regional) levels. While the mechanics of overland water movement and infiltration are generally well understood, there are many significant challenges for system understanding at larger spatial scales, especially under increasingly non-normal weather conditions.

NIBIO endeavors to reconcile measurements and observations with agrohydrological system understanding. Complexity and scale (time and space) are the main challenges in this endeavor. In this presentation we will present how NIBIO uses geophysics for understanding agrohydrological threats and solutions, with focus on drainage, erosion and buffer zones.

How to cite: Bloem, E., Barneveld, R., Krzeminska, D., and Stolte, J.: Geophysics for managing Norwegian agrohydrological threats, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-16030, https://doi.org/10.5194/egusphere-egu23-16030, 2023.

14:15–14:25
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EGU23-297
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SSS9.1
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ECS
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On-site presentation
Gaston Mendoza Veirana, Philippe de Smedt, Jeroen Verhegge, and Wim Cornelis

Near surface geophysical electromagnetic techniques are proven tools to support ecosystem services such as agriculture, soil remediation, nutrient management, and heritage conservation. Key influencing geophysical properties are electrical conductivity (σ, or resistivity (ρ)), dielectric permittivity (𝜀) or magnetic susceptibility (μ), that are targeted to model soil properties and state variables such as texture, bulk density, cation exchange capacity (CEC) or water content. To translate geophysical properties into quantitative information on the targeted soil properties, relationships between these have to be considered in appropriate models. These so-called pedophysical models can then be integrated into interpretation schemes (e.g., after inversion, or through incorporating this into forward modelling procedures). This modelling step, translating geophysical properties into soil properties (and vice versa), thus constitutes a key aspect of near surface exploration.

While hundreds of pedophysical models exist to perform this task, these often depend on many properties and parameters defined within a specific range e.g., electromagnetic frequency, texture, and salinity; impeding applications to cases where information about the studied soil is scarce. Therefore, selecting an appropriate pedophysical model for a given scenario is often a very complex task.

To facilitate solutions for pedophysical modelling we present pedophysics, an open source python package for soil geophysical characterization. The package implements up-to-date models from the literature and, based on the user’s needs, automatically provides an optimal solution given a set of input parameters and the targeted output.

First, a virtual soil is defined by inputting any of its available properties. This soil can be defined in discrete states to simulate the evolution of its properties over time. Secondly, a module (predict) is called to predict the target property of interest. Following this workflow, for example, a soil with a given texture and changing water content could be defined to obtain its 𝜀 or σ at a predefined frequency, or, inversely, its water content could be predicted based on changing σ.

However, as soil properties required as input parameters for pedophysical models are often unknown, it can, in such cases, be impossible to obtain a viable prediction outcome. The pedophysics package accounts for such limitations by implementing pedotransfer functions, that allow obtaining the missing properties from the available ones. For example, if CEC is unknown, it is determined based on soil texture and a location.

In summary, the package synthesizes specific pedophysical modeling knowledge. Time-varying properties can be calculated in a straightforward way, and, through the integration of pedotransfer functions, target properties can be predicted with a minimum of information about the studied soil. Thus, by translating known properties to targeted ones, pedophysics is contributing to improve interpretability of near surface modeling schemes; enhancing soil electromagnetic geophysical exploration techniques in ecosystem services applications.  

How to cite: Mendoza Veirana, G., de Smedt, P., Verhegge, J., and Cornelis, W.: Pedophysics: a python package for soil geophysics., EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-297, https://doi.org/10.5194/egusphere-egu23-297, 2023.

14:25–14:35
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EGU23-13024
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SSS9.1
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On-site presentation
Tarig Bukhary, Johan Alexander Huisman, Haoran Wang, Egon Zimmermann, and Naftali Lazarovitch

The cultivation of date palms (Phoenix dactylifera) is widespread in hyper-arid regions and relies on high-frequency irrigation to achieve satisfactory yields. Adequate irrigation management is of great importance, and requires understanding of the dynamics of sap flow and water storage within the date palm stem. Traditionally, sap flow estimates are obtained using heat dissipation probes. This method provides point estimates that may not represent the spatial distribution of sap flow within the date palm stem. The aim of this study is to investigate whether electrical resistivity tomography (ERT) measurements on date palm stems can be used to obtain information on the spatial distribution of sap flow in order to obtain improved estimates of transpiration. In a first step, laboratory experiments were used to improve understanding of the electrical and hydraulic properties of date palm stems. A laboratory set-up was developed that induced flow in a date palm stem segment using vacuum pressure while making time-lapse ERT measurements. It was found that such ERT monitoring allows to visualize changes in radial flow variability due to different flow conditions. In addition, the electrical conductivity of the outflow was considerably higher than that of the introduced solution, which suggest the presence of stored salt in the stem segment. The relationship between bulk electrical conductivity and water content of date palm stem segments was investigated on smaller samples using multi-step-outflow experiments combined with bulk electrical conductivity measurements. The results showed that the water redistribution in the sample was slow after the initial desaturation, which suggests that the water is tightly bound as in a clay soil. The observed relationship between bulk electrical conductivity and saturation could be described with models established for porous media. In a second step, field experiments were performed that combined ERT and sap flow measurements on both juvenile date palm trees growing in lysimeters and mature date palm trees. For this, a custom-made measurement system was used to acquire high-speed ERT measurements with a temporal resolution of several minutes. The high-resolution monitoring of both the juvenile and mature date palms showed a high spatial variability in electrical conductivity within both the juvenile and mature date palm stems. This has obvious implications for the installation of sap flow sensors, where low-conductivity areas likely indicating regions without flow should be avoided. ERT monitoring also revealed diurnal changes in the spatial distribution of the electrical conductivity that are associated with the tree response to irrigation. An induced drought period for the juvenile date palm in the lysimeter also resulted in a noticeable decrease in the mean electrical conductivity on the second day after irrigation was stopped, suggesting that ERT may also provide an early indicator of water stress.

How to cite: Bukhary, T., Huisman, J. A., Wang, H., Zimmermann, E., and Lazarovitch, N.: Electrical resistivity tomography and sap flow measurements on date palm stems to support irrigation management, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-13024, https://doi.org/10.5194/egusphere-egu23-13024, 2023.

14:35–14:45
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EGU23-7128
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SSS9.1
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ECS
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On-site presentation
Agnese Innocenti, Veronica Pazzi, Marco Napoli, Riccardo Fanti, and Simone Orlandini

Characterization of agricultural soils using geophysical techniques makes it possible to study the heterogeneity of a soil and the preferential pathways of water flows without causing disturbances to soil and plants. Increased knowledge of soil heterogeneity allows the most optimal management of the water resource in terms of crop, yield and sustainability. In this study, time lapse monitoring, using electrical resistivity tomography (ERT), is proposed as a reliable and non-invasive technique to quantify the movement of water flows during the irrigation process.

ERT surveys were conducted in melon cultivated land in southern Tuscany (Italy). Four survey campaigns were carried out between June and August 2022, in which ERT data were collected by taking measurements, before, during, and after the irrigation phase. The investigation was conducted with a 3-D grid in which the 72 electrodes were spaced 0.3 m apart and arranged in three parallel lines, 0.3 m apart and 6.9 m long, for a total of 24 electrodes in each line. The plants were located above a ridge having a height of 20 cm with respect to the ground level and the electrodes were positioned to incorporate 5 melon plants in the configuration. A dipole-dipole configuration was adopted for the acquisition of electrical resistivity data. Commercial ViewLab 3D software was used to process the geoelectrical data.

The interpretation of the ERT results provided information on the spatial and temporal distribution of water flows in the soil and in the root zone of melons during the irrigation phases. The investigation made it possible to identify the preferential ways of infiltration of the irrigation water, the points where the water is absorbed by the roots, and the points where the water instead follows a preferential way distributing itself entirely below the area of root growth. During the investigations, the irrigation time underwent changes dictated by the climatic conditions, therefore the irrigation time and frequency were increased. This manifested itself in the ERT sections with an increase in the conductivity below the roots, i.e., at a depth of about 35 - 40 cm with respect to the ground level. This phenomenon can be explained by the fact that over time the water has developed a greater preferential path, completely bypassed the root system and collected below it, in the zone delimiting the worked soil with the unworked soil.

In the present case study, the ERT technique proved to be a valid survey and monitoring method for mapping the preferential paths of water flows in agricultural land. The ERT sections made it possible to study the distribution of water along the soil profile, highlighting the presence of preferential paths that produce an accumulation of water below the root zone and therefore in an area that is not very usable for cultivation. This technique can therefore be used in this context to study a better irrigation system and an optimal management of the water resource, avoiding preferential paths of the flows which lead to a lower availability of water for the plant.

How to cite: Innocenti, A., Pazzi, V., Napoli, M., Fanti, R., and Orlandini, S.: Electrical Resistivity Tomography (ERT) to assess the drip irrigation water in a field cultivated with melon, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-7128, https://doi.org/10.5194/egusphere-egu23-7128, 2023.

14:45–14:55
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EGU23-8126
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SSS9.1
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ECS
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On-site presentation
Quentin Chaffaut, Myriam Schmutz, and Jehanne Cavailhes

France is one of the largest producer of wine in the world. Thus, viticulture is a major activity area, particularly in south-west of France where vineyards occupy as much as 42% of the agricultural surface. Vineyards worldwide are being subjected to stress brought about by changes in average temperatures, precipitation, seasonal timing that drives phenology, as well as extreme weather events (van Leeuwen, 2004). Specifically, the Bordeaux vineyards are submitted to strong climate change impact, due to the increase in the duration of heat waves (i.e., increase in evaporative demand), and the decrease in summer precipitations (i.e., decrease in water availability in the soils; Soubeyroux et al., 2020). These stressors contribute to Grape yield and quality.

Our approach consists of identifying the factors that control water availability in vineyard soils in order to adapt cultivation practices.

For this purpose, we have instrumented a vineyard plot (~1 ha) in Medoc. This observatory allows the monitoring of water fluxes within the soil-vine-atmosphere continuum on two rows of vines located in areas with contrasting soil types: one is located in a sandy area, while the other is located in a clayey area. The observatory combines:

  • Soil water status monitoring with
  • Spectral Induced Polarization (SIP) measurement campaigns carried out along the two selected rows of vines and repeated at a bi-monthly rhythm,
  • two permanent multi-level soil water content probes
  • Vines water status monitoring using sap flow sensors, together with water potential measurement campaigns repeated on a monthly basis
  • Ground water level continuous measurement sensors
  • Meteorological parameters monitoring

Our observations show that during the drought of the summer 2022, the vines in the sandy row suffer of greater water stress than the vines in the clay row, and that the soil in the sandy row dries out more quickly and to a greater depth than the soil in the clay row. This highlights the impact of soil type on soil water availability. Our early results suggest that in the case of a prolonged drought period, the vines located on clay plots would thus suffer less from water stress than in the case of plots with more draining soil.

Références:

Soubeyroux, JM, Bernus, S, Corre, L, Gouget, V, Kerdoncuff, M, Somot, S, Tocquer, F, 2020. Le nouveau jeu de simulations climatiques régionalisées sur la France pour le service DRIAS, XXXIIIeme colloque de l’Assoc Internat de Climatologie, pp 637-642.

Van Leeuwen, Cornelis, Philippe Friant, Xavier Choné, Olivier Tregoat, Stephanos Koundouras, and Denis Dubourdieu. 2004. Influence of Climate, Soil, and Cultivar on Terroir. American Journal of Enology and Viticulture 55(3):207–17. doi: 10.5344/ajev.2004.55.3.207.

How to cite: Chaffaut, Q., Schmutz, M., and Cavailhes, J.: Impact of drought on the water status of vines in a Bordeaux vineyard, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-8126, https://doi.org/10.5194/egusphere-egu23-8126, 2023.

14:55–15:05
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EGU23-2251
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SSS9.1
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ECS
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solicited
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On-site presentation
Triven Koganti, Diana Vigah Adetsu, Martin Larsen, Kristoffer Skovgaard Mohr, Amélie Beucher, and Mogens H. Greve

Pristine peatlands are precious for their Carbon (C) storage ability and the vast range of ecosystem services they provide. Globally, peatlands were heavily altered over the years especially by draining the water table for meeting energy and agricultural needs. Draining the peat results in its enhanced microbial decomposition, increased dissolved C leaching and increased susceptibility to peat fires, thus turning peatlands into C-source ecosystems. Currently, the carbon dioxide (CO2) released from degraded peatlands amounts to approximately 5% of global anthropogenic emissions. Climate change concerns have sparked an interest to reduce these emissions and different initiatives are put forward for the protection, proper management, and restoration of the peatlands. Denmark has its own national goal of reducing CO2 emissions by 70% by 2030; of which agriculture is expected to be a significant contributor. Comprehensive characterization of peat inventory providing status on the C stocks, water table depths and emissions is required for improved land use planning as almost 4.8 million tonnes of CO2 per annum is released from cultivated organic lands (~ 170,000 ha in total). To achieve this, measurements of peat depth (PD) for volume characterization are invaluable. The conventional mapping approach of PD using peat probes is laborious, time-consuming, and provides only localized and discrete measurements. In addition, these manual probing measurements are also prone to errors as occasionally the probes are obstructed by stones, wood and human artefacts causing underestimation and other times they might easily penetrate the soil underlying the actual peat causing overestimation. In Denmark, we are comparing and contrasting the suitability of different electromagnetic sensors, precisely, working on electromagnetic induction (EMI), ground penetrating radar (GPR), and gamma-ray radiometric (GR) principles to accurately characterize the Danish peatlands. We are testing the sensors on both ground-based and air-borne configurations to improve the feasibility, increase accessibility and save costs. A novel drone-based transient EMI sensor is being designed in this direction. So far the results suggest that the EMI and GR techniques are promising to demarcate the peatland boundaries and estimate the PDs up to a certain extent; depending on the gradient in transition between the mineral and organic soils. Ground penetrating radar provided unequivocal results in high-resistive ombrotrophic peat while failing in low-resistive minerotrophic peat due to low signal penetration. In the drone-borne configuration, GR proved superior due to its ease of use and less to no success was achieved using a GPR. Moving forward, we plan on fusing the multisensor datasets using machine learning to improve the prediction accuracy of PDs, find a means for mapping water table depths and perform advanced modelling for comprehending the effects of different management scenarios on CO2 emissions.

How to cite: Koganti, T., Vigah Adetsu, D., Larsen, M., Skovgaard Mohr, K., Beucher, A., and H. Greve, M.: Sensor-based mapping of Danish peatlands, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-2251, https://doi.org/10.5194/egusphere-egu23-2251, 2023.

15:05–15:15
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EGU23-7736
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SSS9.1
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On-site presentation
Guillaume Blanchy, Ali Mehmandoostkotlar, Bert Everaert, Dominique Huits, Sarah Garré, Thomas Hermans, and Frédéric Nguyen

Polders are areas reclaimed on the sea thanks to hydraulic structures like dikes. To prevent flooding, these low-lying areas are constantly drained by a network of ditches that release excess water in the sea (e.g. at low tide). The use of subsurface drainage pipes connected to existing drainage ditches further enabled the drainage of the lands and made them suitable for agriculture. While the groundwater remains saline water from its seaborn nature, with years and precipitation, a fresh water lens, lighter than the deeper saline water, developed near the soil surface, on top of the saline water. This fresh water lens is essential for most conventional crops that would suffer from saline conditions. The thickness of freshwater lenses varies throughout the year as a function of the recharge from rainfall and evapotranspiration.

However, intensive rainfall events and prolonged summer droughts are becoming more frequent with Climate Change and lead to decreasing freshwater lens thickness, endangering crop yield. Controlled drainage systems that enable to regulate the water level in the subsurface drains has the potential to mitigate this issue by imposing a temporary higher water level, hence increasing recharge of the freshwater lens. 

To better understand the dynamics of the fresh/saline water interface throughout the year, we equipped two fields with multilevel piezometers with both head and salinity sensors replicated three times in each field. Along each multilevel piezometer we also installed 1D resistivity sticks with 16 electrodes to obtain a vertical electrical resistivity profile. In addition, electromagnetic induction surveys enabled us to expand the local observations to the entire area (4 ha in total).

The datasets collected in the two fields in the conventional scenario (i.e. without controlled drainage) during the first year, showcase the usual dynamics of the interface, its lateral as well as vertical variability. The use of geoelectrical techniques enable us to distinguish fresh and saline water boundaries and its variability per soil layers. The electromagnetic induction surveys reveal old paleochannels that influence the dynamics of the freshwater lens at the field-scale. Moreover, the dataset also demonstrates how different crops (grass and flax) lead to different ground water and salinization dynamics. In this work, we present our first year of collected field data and related interpretation before the installation of the controlled drainage system.

How to cite: Blanchy, G., Mehmandoostkotlar, A., Everaert, B., Huits, D., Garré, S., Hermans, T., and Nguyen, F.: Geophysical monitoring of the fresh-saline groundwater interface in Belgian polders, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-7736, https://doi.org/10.5194/egusphere-egu23-7736, 2023.

15:15–15:25
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EGU23-4650
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SSS9.1
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ECS
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On-site presentation
Hira Shaukat, Ken Flower, and Matthias Leopold

Farms in Western Australia (WA) are highly variable in soil texture and water retention capacity; therefore, spatial information of soil moisture status in the field is important for crop management. In practice, farmers often rely on point sensors to determine soil moisture in their fields for crop planning. The limitation of point measurements to account for spatial variability highlights the need to develop methods to assess soil moisture across variable broadacre fields. This information could be used for more effective site-specific crop management practices. In this study, we used a mobile nonintrusive electromagnetic induction (EMI) sensor to map soil apparent electrical conductivity (ECa) and to predict soil moisture levels across the field at three depths (0 – 0.5, 0.5 – 0.8 and 0.8 – 1.6m). The predicted soil moisture was compared with the point measurements of soil moisture sensors and soil samples. The inverted electrical conductivity (EC) from EMI surveys was converted into soil moisture using calibrations between electrical resistivity tomography (ERT) to volumetric moisture, which were developed for the different soil textural classes of the field, with R2 of 0.97 to 0.99. The soil moisture variability of the field was also compared with the spatial distribution of 2019 barley yield production. No significant difference was found between the EMI estimated soil moisture values and the point moisture measurements, as well as moisture extracted from soil samples for 0 – 0.5m and 0.5 – 0.8 m depths with Pearson R values of 0.62 and 0.73 respectively. Barley yield was not correlated with mapped soil moisture or soil texture, which may be due to relatively high initial moisture levels following two years of fallow rotation. This study successfully demonstrated spatial soil moisture estimation using EMI sensor in a field with horizontally and vertically variable soil texture.

How to cite: Shaukat, H., Flower, K., and Leopold, M.: Comparing quasi-3D soil moisture derived from electromagnetic induction with 1D moisture sensors and correlation to barley yield in variable duplex soil, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-4650, https://doi.org/10.5194/egusphere-egu23-4650, 2023.

15:25–15:35
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EGU23-17083
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SSS9.1
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On-site presentation
Sailhac Pascal, Harrouet Titouan, Rivière Agnès, Maugis Pascal, Léger Emmanuel, and Zeyen Hermann

Water transfer through the unsaturated zone, in terms of upward or downward water fluxes, is a critical term for estimation of the water budget. As fluid flow modifies diffusive heat transfer through advective processes, since the early 90s several studies have attempted to deduce vertical water flow from soil temperature series. Likewise, if information on the water content profiles is known, bulk thermal properties can be inferred from thermal time series at different depths.

In this study we compare two field sites in the Paris Basin Area, with two different types of soil and vegetation. We present our preliminary results from two approaches aiming at retrieving inferring soil bulk thermal parameters, namely heat capacity and conductivity, as well as vertical water flow.

On the one hand, thermal measurements until a depth of 1.8 m have been carried out in a managed crop field. Using frequency decomposition of the thermal series, the upward and downward flows are determined. The water fluxes are compared with high-frequency EM time-lapse maps in an attempt to spatialize the variations.

On the other hand, the thermal properties of a wetland area are inferred from soil thermal time series inversion using the thermo-hydrodynamic code suite Ginette, and are compared with spatial distribution of vegetation derived from remote sensing imagery.

The two approaches are compared and discussed with their respective caveats and abilities.

How to cite: Pascal, S., Titouan, H., Agnès, R., Pascal, M., Emmanuel, L., and Hermann, Z.: Determination of upward/downward soil water fluxes using soil thermal profile series : two field case studies, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-17083, https://doi.org/10.5194/egusphere-egu23-17083, 2023.

15:35–15:45
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EGU23-12699
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SSS9.1
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ECS
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On-site presentation
Alberto Carrera, Mirko Pavoni, Ilaria Barone, Jacopo Boaga, Nicola Dal Ferro, Giorgio Cassiani, and Francesco Morari

To address the non-invasive way of studying soil structure and its dynamics at different scales, several geophysical techniques can complement traditional characterization methodologies. In this context, the most widespread methods for soil investigations rely on the different electrical properties of earth materials which change with the content and salinity of the incorporated fluids. Although the use of seismic methods in soil science studies is not as common as for geotechnical and reservoir characterization, seismic wave fields contain information about the mechanical properties of the subsurface and may offer insights about soil compaction that other geophysical methods cannot provide.

In this work, we evaluate the ability of seismic techniques to assess the differences between small and strong degrees of compaction in soils, relating and validating them with traditional direct measurements. The experiment was conducted at the Experimental Farm “L. Toniolo” of the University of Padova in Legnaro (northeastern Italy), under controlled conditions. The acquisition scheme was designed to resolve small-scale seismic velocity contrasts. Three different levels of induced compaction were investigated with indirect (i.e. geophysics) and direct (i.e. bulk density, texture, volumetric water content) measures.

Preliminary results of refraction and surface waves seismic analysis clearly agree with traditional direct measurements. We demonstrate that this approach is not only sensitive to the compaction phenomenon, but it allows to observe both its lateral and in-depth variability. This study opens up interesting future scenarios for geophysics to highlight the different mechanical responses caused both by soil plastic deformation and soil water distribution due to increasing compaction.

 

How to cite: Carrera, A., Pavoni, M., Barone, I., Boaga, J., Dal Ferro, N., Cassiani, G., and Morari, F.: On the use of seismic geophysical methods to characterize different soil compaction levels, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-12699, https://doi.org/10.5194/egusphere-egu23-12699, 2023.

Posters on site: Tue, 25 Apr, 16:15–18:00 | Hall X3

Chairperson: David O Leary
X3.118
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EGU23-5785
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SSS9.1
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ECS
Marco D. Vasconez-Maza, Julien Thiesson, Roger Guerin, Frederic Delarue, Aida Mendieta, and Damien Jougnot

In the mitigating strategies of human impact on environments, the biochar addition to shallow soil horizon represents a promising way among the existing Carbon Dioxide Removal technique. This study is part of a project that aims at evaluating the impact of the presence of biochar in soils on the growth of roots. Geophysical techniques are a good candidate for non-invasive investigation and field monitoring. Among the existing techniques, Electrical Resistivity Tomography (ERT) has already shown great potential for detecting the presence and growth of roots in agricultural soils.

In this study, our goal is to test whether ERT is able to track changes in root growth in a technosol. The field experiment takes place on a setup consisting of 20 plots of 2 meters by 3 meters where the first 0.3 meters were disturbed and for half of them biochar has been incorporated (ca. 2% wt.). As we are expecting 3D effect on this specific field (effects of the limits of the plot, effects of the roots), we design a numerical study to determine the best experimental setup for a 2D ERT profile using pyGIMLi, an open-source software library for geophysical inversion.

We conducted several numerical simulations to determine the optimal dimensions of a meshed body, which was considered as a semi-infinite space, to simulate profiles of 48 and 96 electrodes separated by 0.1 meters. Field measurements on plots with and without biochar showed electric resistivity values of 45 ohm m and 56 ohm m, respectively, suggesting that ERT might be able to detect the biochar presence. Using this information, we focus our numerical simulations on a suitable configuration to assess the effect of biochar onto root growth.

How to cite: Vasconez-Maza, M. D., Thiesson, J., Guerin, R., Delarue, F., Mendieta, A., and Jougnot, D.: Optimisation of an ERT acquisition for soil-plant interaction in presence of biochar, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-5785, https://doi.org/10.5194/egusphere-egu23-5785, 2023.

X3.119
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EGU23-16173
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SSS9.1
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ECS
Daniel Cabrera, Carlos Faundez, and Pablo Diaz

To improve the efficiency of irrigation water application it is necessary to understand 3 important aspects. The depth of wetting reached by each irrigation episode, the overlap between irrigation emitters and the depth where the largest root volume is found. The joint use of electrical resistivity tomography (ERT) with mechanistic hydrological model allows establishing an appropriate irrigation schedule for the particular condition of each irrigation sector, considering aspects for intra-farm soil variability and variations in the root volume of the orchard. For a correct characterization of the existing soil variability in a field, we propose the use of high-resolution ERT (several measurements per hectare) and clustering using k-means for the definition of sites of interest where it is necessary to obtain a petrophysical relationship. (Waxman & Smits, 1968) that allows obtaining the moisture content of the soil from the electrical resistivity of the soil. For the calibration of the mechanistic hydrological model in these same sites, the use of disk infiltrometers measurements is proposed. Through time-lapse ERT measurements in periods between irrigation, it is possible to observe areas of greater water absorption and define areas where there is a greater root volume. Through time-lapse ERT measurements in irrigation episodes, it is possible to determine the depth of wetting reached and use this information to calibrate model parameters of the mechanistic hydrological model. Finally, the use of computer simulations in the defined clusters makes it possible to establish irrigation times and frequencies that ensure a correct overlap between emitters and a wetting depth that reaches the areas of greatest water absorption.

How to cite: Cabrera, D., Faundez, C., and Diaz, P.: The use of high resolution electrical resistivity tomography (ERT) and mechanistic hydrological models to increase the efficiency of the wáter applied by irrigation., EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-16173, https://doi.org/10.5194/egusphere-egu23-16173, 2023.

X3.120
|
EGU23-10520
|
SSS9.1
Soil Water Content Estimation Using Drone-Based Ground Penetrating Radar and Machine Learning Techniques
(withdrawn)
sanaz shafian and Milad Vahidi
X3.121
|
EGU23-5663
|
SSS9.1
Markus Dick, Egon Zimmermann, Johan Alexander Huisman, Achim Mester, Martial Tchantcho Amin Tazifor, Peter Wüstner, Michael Ramm, and Stefan van Waasen

The acquisition of high-resolution soil information is essential for more environmentally friendly and efficient management of agricultural areas in the context of precision farming. The electrical conductivity (EC) of the soil can be measured quickly and without direct contact using electromagnetic induction (EMI) systems. The EC can be related to soil properties such as soil water content, pore water electrical conductivity, nutrition, clay content and salinity. EMI devices provide an apparent conductivity value that averages electrical conductivity variations with depth. To reconstruct the depth-dependent conductivity from measured data, EMI devices with different coil separations between transmitter and receiver or coil orientations are required. For the measurement with different coil separations, measurements with several commercial devices are commonly combined. However, mutual interference between devices is problematic here, so that measurements with the individual devices must be carried out either one after the other or with sufficient spatial separation, which complicates data acquisition substantially. To simplify EMI data acquisition and to improve depth resolution, an EMI device is required that provides simultaneous measurements with a larger number of freely selectable coil distances. To achieve this, a modular scalable multi-coil system (SELMA) with one transmitter and 12 receiver coils was developed. In the first test configuration, the receiver coils are arranged in a coplanar configuration and equally distributed from 0.3 to 3.6 m in a straight line. The system currently operates at a transmission frequency of 20 kHz and is designed for a measurement range from 2 mS/m to 100 mS/m. The noise of the measured apparent electrical conductivity is below 1 mS/m at a measurement rate of 10 Hz. To achieve modularity, decentralised System-on-Chip modules are used for the data acquisition, which are connected to the control unit (PC) via Ethernet. In addition to the apparent conductivity values, temperatures, pressure, and acceleration are recorded. The reliability of the EMI measurements was checked by repeatedly measuring a transect using a custom-made sled.

How to cite: Dick, M., Zimmermann, E., Huisman, J. A., Mester, A., Tchantcho Amin Tazifor, M., Wüstner, P., Ramm, M., and van Waasen, S.: Development of a non-invasive modular electromagnetic induction (EMI) system with spatial high resolution for agricultural applications, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-5663, https://doi.org/10.5194/egusphere-egu23-5663, 2023.

X3.122
|
EGU23-5601
|
SSS9.1
|
ECS
Mario Ramos, Mohammad Farzamian, José Luis Gómez Flores, and Karl Vanderlinde

Multi-receiver electromagnetic induction (EMI) shows increasing potential for effective depth-specific monitoring of shallow soil properties as EMI sensors become available that provide simultaneous apparent electrical conductivity (ECa) measurements for small depths of exploration (DOE). Inversion of such ECa data results in more detailed soil profile EC estimates that can provide a completer understanding the soil hydrology and chemistry near the surface (<1 m depth). We demonstrated this by monitoring the soil status weekly at eight measurement locations in an irrigated cotton field in a saline reclaimed and tile-drained marsh area in SW Spain using a multi-receiver EMI instrument that provided ECa for 12 different DOEs. Soil water content and water table depth and conductivity were monitored at the eight locations. Inversion of the ECa data at the eight locations yielded characteristic EC profiles that depended on soil water content, irrigation and salt leaching, and water table depth. A depth-specific correlation analysis of the EC profiles and their first derivative elucidated the depths where the correlations were strongest and for which the best estimates of water content and water table depth and salinity could be obtained. The established relationships were then used to estimate these properties along two transects that contained each four of the monitoring locations. This approach allowed the detection of areas where a shallow water table emerged during the irrigation season which led to topsoil and crop salinization and can therefore assist decision-making in soil, water and crop management in this area.

 

Acknowledgement

This work is funded by the Spanish State Agency for Research through grant PID2019-104136RR-C21/AEI/10.13039/501100011033 and by IFAPA/FEDER through grant AVA2019.018.

How to cite: Ramos, M., Farzamian, M., Gómez Flores, J. L., and Vanderlinde, K.: Monitoring soil status in an irrigated saline reclaimed marsh area in SW Spain using multi-receiver electromagnetic induction sensing and inversion, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-5601, https://doi.org/10.5194/egusphere-egu23-5601, 2023.

X3.123
|
EGU23-5921
|
SSS9.1
|
ECS
Nebojša Nikolić, Sara Cucchiaro, Eugenio Straffelini, Paolo Tarolli, and Roberta Masin

Weeds pose one of the major threats to plant production, as they can reduce yield, interfere with harvest, and host different harmful organisms. Unlike crops, weeds are characterized by great plasticity and adaptability to agroecosystem changes, making them an even more critical threat in a constantly changing environment. The influence of climate change in the form of different stresses to which plants are being more and more exposed is being extensively studied in crops, yet there are few studies concerning weeds. Still, considering the adaptability potential of weeds, they can represent an even more significant threat to agricultural production when abiotic stress, such as salinity, is introduced in the agroecosystem. Currently, remote sensing techniques may be exploited to derive useful, frequent, and low-cost information at different spatial scales. In this work, the Structure from motion (SfM) technique paired with Unmanned Aerial Vehicles (UAV) was used to map the distribution changes of Abutilon theophrasti in July and August 2022 in three different crop fields in the Po river delta, North-Eastern Italy. The multi-temporal orthomosaics obtained by two various SfM surveys had an image resolution of 2 cm, allowing an accurate photo interpretation and the realization of precise maps of species distribution. In the meantime, different soil samples have been taken from the fields above, and their position was measured by a Global Navigation Satellite System (GNSS), GeoMax Zenith 40. The salinity level of soil samples has been determined by measuring the electrical conductivity using XS Instruments COND 80 electrical conductivity meter (Giorgio Bormac s.r.l, Carpi, Italy) at a sensitivity of 1 µS. Salinity values were spatialized in the study areas, realizing salinity maps through the spatial interpolation tools of the Geographic information system (GIS) software. The salinity maps overlapped the maps of single plants of A. theophrasti. In both of the multi-temporal surveys performed, results show that plants of A. theophrasti can be found in areas where the soil salinity is higher than 8 dS/m, where most of the crop plants have perished.  Considering that the weed plants were present at the same place in both surveys, this indicates that A. theophrasti can tolerate the rise of salinity in the fields better than the crop plants and can therefore outcompete them. These results suggest that soil salinization can have a double negative effect on crop production, both causing abiotic stress and increasing competition.

Acknowledgments: This study was carried out within the Agritech National Research Center and received funding from the European Union Next-GenerationEU (PIANO NAZIONALE DI RIPRESA E RESILIENZA (PNRR) – MISSIONE 4 COMPONENTE 2, INVESTIMENTO 1.4 – D.D. 1032 17/06/2022, CN00000022).

How to cite: Nikolić, N., Cucchiaro, S., Straffelini, E., Tarolli, P., and Masin, R.: Remote sensing techniques to assess the weeds adaptability to salinity stress induced by soil changes, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-5921, https://doi.org/10.5194/egusphere-egu23-5921, 2023.

X3.124
|
EGU23-9070
|
SSS9.1
|
ECS
Valeh Khaledi, Gunnar Lischeid, Bahareh Kamali, Ottfried Dietrich, and Claas Nendel

Introduction

Every grassland has considerable annual vegetation composition dynamics, especially in sites with shallow water levels (Toogood & Joyce, 2009). These wet grasslands, where the vegetation is regularly consuming capillary water, are very sensitive to water availability and respond rapidly by changing their species composition. As different species produce different biomass, the biomass yield is constantly altering alongside species composition change (White et al., 2000). These dynamics limit the use of mechanistic models for the prediction of biomass yields, especially in response to the water supply. Grassland models have been developed to simulate vegetation growth since the late 1980s (Coffin & Lauenroth, 1990; Thornley & Verberne, 1989). However, none of the existing models can deal with capillary water ascending from shallow groundwater considering the vegetation composition change. In this study, we demonstrate that mechanistic plant growth models for grassland productivity would benefit from the consideration of vegetation composition change in wet grasslands.

Material and method

The data from an extensively agriculturally used wet grassland lysimeter station in Germany, Spreewald (SPW, 51◦52´ N, 14◦02´ E, 50.5 m above sea level) (Dietrich & Kaiser, 2017) was used in this study. In this study, we followed an analytical approach and a modeling approach to reveal the importance of vegetation composition change impact on biomass yield prediction. First, we did a Pearson correlation analysis between vegetation composition indices and biomass. In the modeling approach, the mechanistic process-based simulation model MONICA (MOdel for NItrogen and Carbon dynamics in Agroecosystems) was employed to simulate water fluxes in the soil. In the model, an empirical approach was used for ascending water in the capillary fringe above the groundwater table, using daily rise rates from the German Soil Survey Manual ("Bodenkundliche Kartieranleitung. ," 2005)

Results

The correlation analysis showed a significant association between the vegetation index and biomass yield, with a time lag of one year between the groundwater level and the respective response in the vegetation index. The results from the modeling approach showed that the model did not reproduce the year-to-year variation in biomass well. However, when we removed the effect of the groundwater level on the vegetation composition from the biomass data, the simulation model agreed much better with the remaining pattern. As a result, we conclude that long-term biomass patterns can only be reproduced with mechanistic simulation models when vegetation composition dynamics are considered, e.g. by using it alongside a species competition model.

Keywords: Wet grassland, vegetation composition, capillary rise, process-based model

Reference

Dietrich, O., & Kaiser, T. (2017). Impact of groundwater regimes on water balance components of a site with a shallow water table [RESEARCH A R T I C L E]. Ecohydrology.

Toogood, S., & Joyce, C. (2009). Effects of raised water levels on wet grassland plant communities. Applied Vegetation Science, 12, 283-294.

White, R., Murray, S., & Rohweder, M. (2000). PILOT ANALYSIS OF GLOBAL ECOSYSTEMS (Grassland Ecosystems).

How to cite: Khaledi, V., Lischeid, G., Kamali, B., Dietrich, O., and Nendel, C.: Wet grassland biomass yield prediction considering species composition dynamic, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-9070, https://doi.org/10.5194/egusphere-egu23-9070, 2023.

X3.125
|
EGU23-10467
|
SSS9.1
|
ECS
The radiation interception and transmission in strip intercropping system
(withdrawn)
Liming Dong, Wenzhi Zeng, Yuchao Lu, and Jiesheng Huang
X3.126
|
EGU23-11597
|
SSS9.1
|
ECS
Tibor Zsigmond, Imre Zagyva, and Ágota Horel

In agricultural systems, rapid information from data collection and processing is an important factor for stakeholders and researchers to correctly account for the spatial and temporal variability of crop and soil factors. The aim of the present study was to investigate soil-plant-water systems and interactions using manual and remote sensing techniques in a small agricultural catchment. Four land use types of forest, grassland, vineyard, and cropland (sunflower) were investigated in different slope positions. At the same time, three different tillage practices were applied in the vineyard between the rows: grassed (NT), cover cropped (CC), and tilled (T) inter rows. We evaluated NDVI measurements from three different sources (PlantPen - PP, Meter Group - MG, Sentinel-2 - S2) representing different scales (leaves, 0.33m2, and 100m2). We also compared ground and satellite measurements of varying vegetation indices.

Spectral reflectance sensors were used on the slopes of grassland, cropland, and three vineyard sites. The Normalized Difference Vegetation Index (NDVI) and Photochemical Reflectance Index (PRI) sensors were used to measure leaf reflectance. A hemispherical sensor set was used for each measurement. Hand-held instruments were used to measure the topsoil soil water content (SWC) and temperature, leaf NDVI and chlorophyll concentrations, and Leaf Area Index (LAI) every two weeks. Satellite data, such as NDVI, green (GCI) and red edge (RECI) chlorophyll indices, and soil-adjusted vegetation index (SAVI), were obtained from the Sentinel-2 database on days when both ground and satellite overpass occurred within 24 hours.

Land use types and slope position have a strong influence on vegetation growth. The highest overall NDVI and leaf chlorophyll values were observed in vineyard and forest samples, and the lowest in grassland. SWC and temperature were the lowest in the forest and vineyards. SWCs were significantly different for T and CC samples (p<0.05) based on slope positions, while soil temperatures were not significantly different between upper and lower slope positions (p>0.05). For the other three land use types, there were no significant differences in values between slope positions. Chlorophyll data showed a very strong correlation between Sentinel-2 retrieved data and hand-held measurements, with r=0.84 for grassland (GCI), r=0.83 for NT (GCI), and r=0.87 for T (RECI). Strong correlations were found between the different sources of NDVI for the grassland samples (e.g. r=0.97, p<0.05 for S2 and MG). Weaker correlations were observed between different inter-row managed vineyard samples (e.g. for tilled inter-row r=0.70 between S2 and PP and r=0.35 between S2 and MG). Since inter-row management strongly influences the overall values of S2, adjustments are needed.

How to cite: Zsigmond, T., Zagyva, I., and Horel, Á.: Comparison of vegetation indices using measurement techniques on a scale from plant leaves to plots, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-11597, https://doi.org/10.5194/egusphere-egu23-11597, 2023.

X3.127
|
EGU23-13502
|
SSS9.1
|
ECS
MHD Wael Al Hamwi, Mathias Hoffmann, Joerg Schaller, Mathias Stein, Michael Sommer, Shrijana Vaidya, Katja Kramp, Valerie Pusch, Reena Macagga, Gernot Verch, Norbert Bonk, Peter Rakowski, and Maren Dubbert

Crop production is affected by drought duration and severity, which become more frequent with climate change. Several studies reported the positive effect of Silicate (Si) fertilization on soil and plant water balance. However, the relation between soil type and the impact of Silicate (Si) fertilization on plant performance, as well as the underlying mechanism for water stress tolerance, is poorly understood. To investigate the effect of Si fertilization on soil-plant-water relation in different soil types, we set up a Si fertilization experiment in an arable landscape of Northeast Germany (Uckermark region, 53° 23' N, 13° 47' E) using Barley (Hordeum vulgare) at three different sites with different soil types and erosion stages: 1) Haplic luvisol (non-eroded), 2) Haplic Regesol (extremely eroded) and 3) Endogleyic colluvic regosol (deposition). 3 Kg "Aerosil 300"   are applied to the soil (~1% ASi in topsoil) compared to control plots (no fertilization), with four replicates per treatment at each site. A campaign of 2-3 consecutive days was conducted throughout the experiment period (from April to July 2022) every two weeks. During these campaigns, we measured leaf water potential, gas fluxes (CO2 and Evapotranspiration), NDVI (normalized difference vegetation index) and biomass sampling. Soil water content and temperature were continuously monitored by soil sensors planted in situ at each plot. We harvested Barley at the end of the growing season and measured each plot's plant biomass and seed production. Our data showed that Si fertilization significantly increased the soil water content in the different soil erosion stages by 2-3%. At the plant's early growth stage, the increase in the soil water content related to Si fertilization significantly affected drought mitigation, balancing leaf water potential decrease during drought. Moreover, while plant development was not generally affected by Si fertilization, germination was delayed in non-fertilized plots. However, the vegetation period in 2022 was rather wet and a drought occurred only during the early phenological development of the plant, and no significant effects of Si fertilization on plant performance were visible (leaf water potential, net ecosystem exchange, evapotranspiration, NDVI and yield) after the early stages. Thus, no lasting effect of Si fertilization on drought mitigation on Barley could be detected, as Barley recovered quickly from drought during the early vegetation stage, irrespective of Si fertilization. All things considered, Si fertilization as an approach to enhance plant tolerance during drought is more complex than previously expected. Our results suggest that the timing and duration of drought, as well as soil type, are important factors to consider.

Keywords: Si fertilization, Drought, Soil erosion, Water Stress, Soil water content, Leaf water potential, NDVI, Gas fluxes, Plant performance.

How to cite: Al Hamwi, M. W., Hoffmann, M., Schaller, J., Stein, M., Sommer, M., Vaidya, S., Kramp, K., Pusch, V., Macagga, R., Verch, G., Bonk, N., Rakowski, P., and Dubbert, M.: In-situ effect of Si fertilization on Soil-plant-water relation for different soil erosion states, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-13502, https://doi.org/10.5194/egusphere-egu23-13502, 2023.

X3.128
|
EGU23-14364
|
SSS9.1
|
ECS
Tadesse Gashaw Asrat, Stephan M Haefele, Ruben Sakrabani, Kirsty L Hassall, Fassil Kebede, Timo Breure, and Ron Corstanje

Proximal soil spectroscopy can be useful to estimate relevant soil properties in real time and cheaply for agricultural decision support and soil health monitoring. However, prediction performance of plant available soil phosphorus by the visNIR has been unsatisfactory as it is considered among the least spectrally active soil properties. Hence, we compared prediction performance among plant available soil phosphorus (Olsen P), extractable soil phosphorus (ammonium-oxalate extract of P - AmOxP), total soil phosphorus (Aqua regia extract of P - TP) and phosphorus buffer index (PBI) using visNIR soil spectral sensing instrumentations (Neospectra and Fieldspec-4) using East African agricultural soils. The comparison was made by scanning 360 archived soil samples which were collected from 0-20cm soil depth in Ethiopia, Kenya and Tanzania. The spectra data was pre-treated with SavitskyGolay smoothing + first derivative and a PLSR was used to develop the predictive models from a 75% of the dataset (#270) subsampled by a conditioned Latin Hypercubic sampling (cLHS) method using the spectra space. The model performance was evaluated by an independent set of samples (#90) by calculating the concordance correlation coefficient (CCC), ratio of performance to interquartile range (RPIQ), bias and root mean square error of prediction (RMSEP).  The most important wavelengths for all soil P indicators in the NIR instrument ranged between 2150 -2400 nm whereas it included 500-570 nm for the visNIR instrument. PBI was predicted with higher CCC value of 0.94 and 0.89 for visNIR and NIR, respectively, however it has the least RPIQ (0.4 and 0.3, respectively) values when compared to other soil P prediction by both instruments. TP and AmOxP were predicted with higher accuracy and model consistency when compared to OlsenP and PBI. The visNIR range gave better prediction accuracy and model consistency for all soil P indicators than the NIR range. Hence, our findings indicated that TP and AmOxP could be preferred to predict soil phosphorus status for any agricultural and soil health monitoring using soil spectroscopic techniques.

Keywords: proximal soil spectroscopy, PLSR model, Savitzky-Golay smoothing filter, first derivative, Neospectra, Fieldspec-4, East Africa.

How to cite: Asrat, T. G., Haefele, S. M., Sakrabani, R., Hassall, K. L., Kebede, F., Breure, T., and Corstanje, R.: Soil phosphorus prediction by visNIR could be dependent on the conversional P determination method, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-14364, https://doi.org/10.5194/egusphere-egu23-14364, 2023.

X3.129
|
EGU23-15692
|
SSS9.1
|
Erika Budayné Bódi, Erika Kutasy, József Csajbók, Solange Paola Acosta Santamaría, Tamás Magyar, Nikolett Szőllősi, Zsolt Zoltán Fehér, Péter Tamás Nagy, Attila Nagy, and Tamás János

Five winter oat (Avena sativa L.) varieties were set in a small-plot field experiment to examine the abiotic stress considering silicone and sulphur foliar fertilization treatments under temperate and dry climatic conditions in Hungary. Numerous in situ and laboratory measurements were performed to describe the crop's condition at various phenological stages. Drones with multispectral, thermal and LiDAR payloads monitored the field both with high temporal and spatial resolution. A high level of GIS data assimilation was performed in order to handle the different spatial-related parameters in one interface.

It is a multi-purpose experiment, and for all of them it is an important criterion whether the study was carried out in a truly homogeneous area. Practically, it means that we ignore the patterns of the crop or the soil. If this is not the case, the various parameters measured should be evaluated accordingly. Hence, our study's main goal here is to reveal the soil and crop heterogeneity level. For this, all the measured parameters are involved in the multi-parameter analysis by which the heterogeneity level of the site can be assessed.

Practically, by this, we can answer the main question: is the field suitable to carry out analysis such as abiotic stress studies or yield prediction modelling on it or shall we handle certain parts differently?

Based on the example of our experiment we design a workflow by which the heterogeneity level of a small-plot field can be assessed and provide a solution for how to handle it in order not to involve data which may mislead analysis.

How to cite: Budayné Bódi, E., Kutasy, E., Csajbók, J., Acosta Santamaría, S. P., Magyar, T., Szőllősi, N., Fehér, Z. Z., Nagy, P. T., Nagy, A., and János, T.: UAV-based heterogeneity analysis of soil-plant-water system of small-plot experiment with different oat genotypes under Si and S foliar fertilization treatments, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-15692, https://doi.org/10.5194/egusphere-egu23-15692, 2023.