References of "Garré, Sarah"
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See detailHow does STICS crop model simulate crop growth and productivity under shade conditions?
Artru, Sidonie ULiege; Dumont, Benjamin ULiege; Ruget, Francois et al

in Field Crops Research (2018), 215

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See detailChapter Ground-based soil moisture determination. In: Ecohydrology. Observation and Measurement of Ecohydrological Processes
Jonard, François; Bogena, Heye; Caterina, David et al

Book published by Springer (2018)

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See detailA forward model for electrical conduction in soil-root continuum: a virtual rhizotron study
Rao, Sathyanarayan; Meunier, Félicien; Ehosioke, Solomon ULiege et al

Poster (2017, November 23)

Electrical Resistivity Tomography monitoring of soil-root system water fluxes have received growing interest in the past decades. Some studies suggest that roots can be more electrically conductive than ... [more ▼]

Electrical Resistivity Tomography monitoring of soil-root system water fluxes have received growing interest in the past decades. Some studies suggest that roots can be more electrically conductive than soil. We suggest that ERT data taken in agricultural fields is impacted by plant roots and might contaminate estimates of soil water content based on bare soil petrophysical relations. To understand how do roots impact electrical current flow and thus ERT data, a numerical electrical model was coupled with a mechanistic maize-soil water flow model. All the maize roots with a radius larger than 0.05 cm were explicitly accounted for in the finite element mesh and associated to their specific electrical properties. Root growth and water uptake processes continuously affected the EC contrast between soil and root. We demonstrated that high contrats between root and soil EC lead to errors in the estimation of soil water content, which could be disminished by using an appropriate biopedophysical correction term. The effective EC (bulk properties) of the medium computed using simulated plate electrodes at rhizotron boundaries reveal directional anisotropy induced by root processes and is more pronounced in sand medium when compared to loam. The percentage change in bulk EC due to change in direction (𝐸𝐸𝐸𝐸ℎ𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜 .vs. 𝐸𝐸𝐸𝐸𝑣𝑣𝑣𝑣𝑣 𝑣 𝑣𝑣𝑣𝑣𝑣 𝑣 ) starts at ~30 % in sand and ~3 % in loam when root is young and increases upto ~500% in sand and ~20% in loam at day 22 when root is three weeks old. Directions in which there is more anisotropy contains more information on the root processes and hence they can be used as prior information for ERT injection scheme to retrieve better information. [less ▲]

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See detailImpact of spatio-temporal shade dynamics on wheat growth and yield, perspectives for temperate agroforestry
Artru, Sidonie ULiege; Garré, Sarah ULiege; Dupraz, Christian et al

in European Journal of Agronomy (2017)

A stumbling block to the adoption of silvoarable agroforestry systems is the lack of quantitative knowledge on the performance of different crops when competing for resources with trees. In North-Western ... [more ▼]

A stumbling block to the adoption of silvoarable agroforestry systems is the lack of quantitative knowledge on the performance of different crops when competing for resources with trees. In North-Western Europe, light is likely to be the principal limiting resource for understorey crops, and most agronomic studies show a systematic reduction of final yield as shade increases. However the intensity of the crop response depends on both the environmental conditions and the shade characteristics. This study addressed the issue by monitoring winter wheat (Triticum aestivum L.) growth, productivity and quality under artificial shade provided by military camouflage shade-netting, and using the Hi-sAFe model to relate the artificial shade conditions to those applying in agroforestry systems. The field experiment was carried out over two consecutive years (2013–14 and 2014–15) on the experimental farm of Gembloux Agro-Bio Tech, Belgium. The shade structures recreated two shade conditions: periodic shade (PS) and continuous shade (CS), with the former using overlapping military camouflage netting to provide discontinuous light through the day, and the latter using conventional shade cloth. The experiment simulated shading from a canopy of late-flushing hybrid walnut leaves above winter wheat. Shading was imposed 16 (2013–14) and 10 (2014–15) days before flowering and retained until harvest. The crop experienced full light conditions until the maximum leaf area index stage (LAImax) had been reached. In both years, LAI followed the same dynamics between the different treatments, but in 2013–2014 an attack of the take-all disease (Gaeumannomyces graminis var. tritici) reduced yields overall and prevented significant treatment effects. In season 2014–15 the decrease in global radiation reaching the crop during a period of 66 days (CS: – 61% and PS: – 43%) significantly affected final yield (CS: – 45% and PS: – 25%), mainly through a reduction of the average grain weight and the number of grain per m2. Grain protein content increased by up to 45% under the CS treatment in 2015. Nevertheless, at the plot scale, protein yield (t/ha) did not compensate for the final grain yield decrease. The Hi-sAFe model was used to simulate an agroforestry plot with two lines of walnut trees running either north-south or east-west. The levels of artificial shade levels applied in this experiment were compared to those predicted beneath trees growing with similar climatic conditions in Belgium. The levels used in the CS treatment are only likely to occur real agroforestry conditions on 10% of the cropped area until the trees are 30 years old and only with east-west tree row orientation. [less ▲]

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See detailEffects of a ‘one film for 2 years’ system on the grain yield, water use efficiency and cost-benefit balance in dryland spring maize (Zea mays L.) on the Loess Plateau, China
Chen, Baoqing; Yan, Changrong; Garré, Sarah ULiege et al

in Archives of Agronomy and Soil Science (2017)

‘One film for 2 years’ (PM2) has been proposed as a practice to control the residual film pollution; however, its effects on grain-yield, water-use-efficiency and cost-benefit balance in dryland spring ... [more ▼]

‘One film for 2 years’ (PM2) has been proposed as a practice to control the residual film pollution; however, its effects on grain-yield, water-use-efficiency and cost-benefit balance in dryland spring maize production have still not been systematically explored. In this study, we compared the performance of PM2 with the annual film replacement treatment (PM1) and no mulch treatment (CK) on the Loess Plateau in 2015-2016. Our results indicated the following: (1) PM2 was effective at improving the topsoil moisture (0-20 cm) at sowing time and at seedling stage, but there was no significant influence on soil water storage, seasonal average soil moisture or evapotranspiration; (2) PM2 induced significantly higher cumulative soil temperatures compared to CK, and there was no significant difference between PM2 and PM1; (3) no significant differences were identified in grain-yield and water-use-efficiency between PM1 and PM2, and compared to CK, they improved by 16.3% and 15.5%, respectively; (4) because of lower cost of plastic film, tillage, film laying and remove in PM2, economic profits improved by 21% and 70% compared to PM1 and CK. This research suggested that PM2 was effective at alleviating the spring drought and was beneficial in reducing poverty traps in dryland. [less ▲]

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See detailThe mathematical challenges in agrogeophysics: examples and ways ahead
Garré, Sarah ULiege; Nguyen, Frédéric ULiege; Lesparre, Nolwenn ULiege et al

Conference (2017, October 05)

Electrical resistivity tomography (ERT) is increasingly used in the context of agriculture since the measured resistivity distribution can be linked to soil moisture, soil structure or pore water salinity ... [more ▼]

Electrical resistivity tomography (ERT) is increasingly used in the context of agriculture since the measured resistivity distribution can be linked to soil moisture, soil structure or pore water salinity. Due to its minimally invasive character, its spatial coverage and its monitoring abilities, ERT can be used to study field heterogeneity and competition between plants, quantify water fluxes throughout a growing season or distinguish preferential flow pathways in soils. Nevertheless, a lot of challenges still remain. From a mathematical point of view, the inverse problem linked to ERT is ill-posed. To solve it, the inverse problem is often regularized with a Tikhonov-type approach. The latter is typically done using a gradient operator, resulting in smoothed resistivity distribution. However, strong contrasts can exist due to e.g. compacted soil layers due to ploughing, water infiltration fronts, etc. In such a case, other operators such as the total variation or the minimum gradient support may be used. In such approaches, the selection of the regularization parameter with respect to the data quality and the definition of image appraisal indicators still remains a challenge. Uncertainty quantification of ERT-derived results often relies on data-error propagation around the inverse solution. Given the inherent non-uniqueness of the problem, both mathematically but also from a pedological point of view, challenges for stochastic approaches lie in providing realistic uncertainty estimation, encompassing all uncertainties (e.g. prior, pedophysics or data error). Monitoring data allows further elements to constrain the inverse problems, data can be replaced by data difference and regularization may incorporate the temporal dimension for instance. However, such constraints require their compatibility with the studied temporal process. Whereas the above challenges stay true for monitoring data, several alternative strategies are being developed more specifically, such as coupled hydrogeophysical inversion, with the challenge of addressing the non-stationarity of pedophysical relationships and the accuracy of the conceptual flow and transport model using deterministic approaches. Stochastic approaches allow to a certain extent to tackle those challenges in particular using a prior falsification/validation approach following a Popper-Bayes philosophy. In this presentation, we will illustrate the challenges and some of the recent developments with numerical and field examples. [less ▲]

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See detailSpatiotemporal variation of drought characteristics in the Huang- Huai-Hai Plain, China under the climate change scenario
Li, Xiangxiang; Ju, Hui; Garré, Sarah ULiege et al

in Journal of Integrative Agriculture (2017), 16(10), 2308-2322

Understanding the potential drought characteristics under climate change is essential for reducing <br />vulnerability and establishing adaptation strategies, especially in the Huang-Huai-Hai Plain (3H ... [more ▼]

Understanding the potential drought characteristics under climate change is essential for reducing <br />vulnerability and establishing adaptation strategies, especially in the Huang-Huai-Hai Plain (3H Plain) which is the grain production base in China. In this paper, the variation of drought characteristics including drought event frequency, duration, severity and intensity for the past 50 years (1961-2010) and future scenarios (2010-2099) based on observed meteorological data and RCP 8.5 projections were investigated, respectively. Firstly, the applicability of three climatic drought indices including the Standardized Precipitation Index (SPI), the Standardized Precipitation Evapotranspiration Index based on the Penman–Monteith equation (SPEI-PM) and the Thornthwaite equation (SPEI-TH) were compared in tracing recorded agricultural drought areas. Then, the drought characteristics including drought event, duration, severity and intensity using “run theory” was analyzed for both historical observations and future RCP 8.5 scenarios based on the proper index. Correlation analysis between drought indexes and agricultural drought areas showed that SPEI-PM performed better than SPI and SPEI-TH in the 3H Plain. Based on the results of SPEI-PM, droughts over the past 50 years have experienced reduced drought with shorter durations, and weaker severity and intensity. However, for the future RCP 8.5 scenario, drought is predicted to rise in frequency, duration, severity and intensity from 2010-2099 although drought components during the 2010-2039 were milder compared to historical conditions. This study highlights that the estimations for atmospheric evaporative demand would bring in differences in long term drought trend of drought indexes and consequently the applicability in 3H Plain. The results of this paper can help inform researchers and local policy makers to establish drought risk management strategies. [less ▲]

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See detailInfluence of rock fragments on hydraulic properties of Ultisols in Ratchaburi Province, Thailand
Khetdan, Channarong; Chittamart, Natthapol; Tawornpruek, Saowanuch et al

in Geoderma Regional (2017), 10

In Thailand, stony soils are mainly located in hillside areas. Even though they have physical limitations for agricultural use and they are exposed to a risk for soil erosion, they continue to be used for ... [more ▼]

In Thailand, stony soils are mainly located in hillside areas. Even though they have physical limitations for agricultural use and they are exposed to a risk for soil erosion, they continue to be used for crop production. A good understanding of the hydraulic characteristics of soils containing an important fraction of rock fragments is crucial for soil and water management in these areas. The objective of this study was to investigate the influence of different rock fragment contents on effective hydraulic properties of skeletal soil with a clay content lower than 35% using measurements of the water retention curve and the hydraulic conductivity. A tension infiltrometer was used to determine the field hydraulic conductivity at four pressure heads (h) of 0, − 30, − 60 and − 120 mm. Soil water retention was determined on a pressure plate between − 33 and − 1500 kPa. Finally, the Hydrus-1D was used to predict soil moisture dynamics using the obtained effective hydraulic parameters. The results show a decreasing water retention capacity with increasing rock fragment content. The saturated hydraulic conductivity decreased with increasing stone contents from 0 to 20%, but then increased for increasing stone content. Contradicting behavior can be observed using field and lab measurements, clearly exposing the need for a better understanding of the functioning of stony soils. [less ▲]

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See detailThe effect of initial water distribution and spatial resolution on the interpretation of ERT monitoring of water infiltration
Dumont, Gaël ULiege; Pilawski, Tamara ULiege; Robert, Tanguy et al

Poster (2017, July 25)

A better understanding of the water balance of a landfill is crucial for its management, as the waste water content is the main factor influencing the biodegradation process of organic waste. In order to ... [more ▼]

A better understanding of the water balance of a landfill is crucial for its management, as the waste water content is the main factor influencing the biodegradation process of organic waste. In order to investigate the ability of long electrical resistivity tomography (ERT) profiles to detect zones of high infiltration in a landfill cover layer, low resolution time lapse data were acquired during a rainfall event. Working at low resolution allows to cover large field areas but with the drawback of limiting quantitative interpretation. In this contribution, we use synthetic modeling to quantify the effect of the following issues commonly encountered when dealing with field scale ERT data: (i) the effect of low resolution on electrical resistivity changes interpretation, (ii) the effect of the original heterogeneous resistivity distribution on the observed relative resistivity changes, (iii) the need for temperature and pore fluid conductivity data in order to compute water content and absolute changes of water content, and (iv) the interpretation error commonly made while neglecting the dilution effect during fresh water infiltration. Firstly, due to the lack of spatial resolution, the regularized inversion process yields a smoothed distribution of resistivity changes that fail to detect small infiltration zones and yields an overestimation of the infiltration depth and an underestimation of the infiltrated volume in large infiltration areas. Secondly, the analysis of relative changes, as commonly used in literature, is not adequate when the background water content is highly heterogeneous. In such a case, relative changes reflect both the initial water content distribution and the observed changes. Thirdly, the computation of absolute water content changes better reflects the infiltration pattern, but requires spatially distributed temperature and pore fluid conductivity input data. Lastly, the dilution effect, if not considered, leads to an underestimation of the infiltrated volume. Taking into account these elements, we extracted the maximum amount of information from our field data without over-interpreting the results. This allowed the detection of larger infiltration areas possibly responsible for a large part of the annual water infiltration and landfill gas loss. [less ▲]

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See detailUsing crop modelling to determine the meteorological conditions to be implemented in an Ecotron facility - Prerequisites to improve the experimental design?
Dumont, Benjamin ULiege; Leemans, Vincent ULiege; Garré, Sarah ULiege et al

Poster (2017, May 23)

An Ecotron is a facility where ecosystems are confined in experimental chambers, allowing the simultaneous control of environmental conditions and the on-line monitoring of processes. Under the threats of ... [more ▼]

An Ecotron is a facility where ecosystems are confined in experimental chambers, allowing the simultaneous control of environmental conditions and the on-line monitoring of processes. Under the threats of climate change and the pressure of a world growing population, such facilities will be of major importance to study the relations between climate change and agro-ecosystems.As it can quickly become time- and money-consuming, conducting experiments in an Ecotron will force researchers to cautiously select the climate of interest to be generated. They will thus need reliable tools to help them support the decision making process.Here, we present an innovative methodology, supported by the use of crop model, to assist researchers in finding the climatic conditions under which crop services will be impacted.The meteorological datasets among which the choice can be done were generated by the ALARO-0 model (RMI, Belgium) for current and future climatic conditions. Runs were conducted for the historical period 1981-2010, and for two time frames - 2041-70 and 2071-2100 - under two emissions scenarios - RCP 4.5 and 8.5.A crop model (STICS, INRA, FR) was run over the entire database. Crop model outputs were synthesized for the main crop phenological phases, i.e. the juvenile, vegetative and reproductive phases. A particular emphasis was put on agronomical outputs (biomass and grain yield) and crop growth stresses (deficit and excess of water, thermal and nutrient stresses).Using these outputs as selection criteria, a novel multi-criteria approach was designed to retro-select the specific climatic conditions allowing to reach certain outcomes (e.g. yield target) while simultaneously exhibiting given thresholds of stresses for any considered crop stages. [less ▲]

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See detailDeveloping suitable methods for effective characterization of electrical properties of root segments
Ehosioke, Solomon ULiege; Phalempin, Maxime; Garré, Sarah ULiege et al

Conference (2017, April 28)

Developing suitable methods for effective characterization of electrical properties of root segments Solomon Ehosioke (1), Maxime Phalempin (2), Sarah Garré (3), Andreas Kemna (4), Sander Huisman (5 ... [more ▼]

Developing suitable methods for effective characterization of electrical properties of root segments Solomon Ehosioke (1), Maxime Phalempin (2), Sarah Garré (3), Andreas Kemna (4), Sander Huisman (5), Mathieu Javaux (2), and Frédéric Nguyen (1) (1) Department of Architecture, Geology, Environment & Constructions, university of Liege, Liège, Belgium, (2) Earth and Life Institute, Environmental Science, Université catholique de Louvain, Louvain-la-Neuve, Belgium, (3) Biosystems Engineering Department, Gembloux Agro-Bio Tech, University of Liege, Gembloux, Belgium, (4) Department of Geophysics, Steinmann Institute, University of Bonn, Germany, (5) Agrosphere (IBG3), Forschungszentrum Ju¨lich GmbH, Ju¨lich, Germany The root system represents the hidden half of the plant which plays a key role in food production and therefore needs to be well understood. Root system characterization has been a great challenge because the roots are buried in the soil. This coupled with the subsurface heterogeneity and the transient nature of the biogeochemical processes that occur in the root zone makes it difficult to access and monitor the root system over time. The traditional method of point sampling (root excavation, monoliths, minirhizotron etc.) for root investigation does not account for the transient nature and spatial variability of the root zone, and it often disturbs the natural system under investigation. The quest to overcome these challenges has led to an increase in the application of geophysical methods. Recent studies have shown a correlation between bulk electrical resistivity and root mass density, but an understanding of the contribution of the individual segments of the root system to that bulk signal is still missing. This study is an attempt to understand the electrical properties of roots at the segment scale (1-5cm) for more effective characterization of electrical signal of the full root architecture. The target plants were grown in three different media (pot soil, hydroponics and a mixture of sand, perlite and vermiculite). Resistance measurements were carried out on a single segment of each study plant using a voltmeter while the diameter was measured using a digital calliper. The axial resistance was calculated using the measured resistance and the geometric parameters. This procedure was repeated for each plant replica over a period of 75 days which enabled us to study the effects of age, growth media, diameter and length on the electrical response of the root segments of the selected plants. The growth medium was found to have a significant effect on the root electrical response, while the effect of root diameter on their electrical response was found to vary among the plants. More work is still required to further validate these results and also to develop better systems to study the electrical behaviour of root segments. Findings from our review entitled “an overview of the geophysical approach to root investigation”, suggest that SIP and EIT geophysical methods could be very useful for root investigations, thus more work is in progress to develop these systems for assessing the root electrical response at various scales. [less ▲]

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See detailAgroforestry in temperate regions: where does the water go?   A case study with ERT in a corn field bordered by poplar trees.
MALOTEAU, Sophie ULiege; Coussement, Tom; Pardon, Paul et al

Conference (2017, April 28)

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See detailThe potential of non-invasive electrical techniques for agricultural  experiments
Garré, Sarah ULiege

Scientific conference (2017, April 06)

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See detailImpact of climate change on potential evapotranspiration under a historical and future climate scenario in the Huang-Huai-Hai Plain, China
Liu, Qin; Yan, Changrong; Ju, Hui et al

in Theoretical & Applied Climatology (2017)

Climate change is widely accepted to be one of the most critical problems faced by the Huang-Huai-Hai Plain (3H Plain), which is a region in which there is an over-exploitation of groundwater region and ... [more ▼]

Climate change is widely accepted to be one of the most critical problems faced by the Huang-Huai-Hai Plain (3H Plain), which is a region in which there is an over-exploitation of groundwater region and where future warmer and drought conditions might intensify crop water demand. In this study, the spatiotemporal patterns of ET0 and primary driving meteorological variables were investigated based on a historical and RCP 8.5 scenario daily data set from 40 weather stations over the 3H Plain using linear regression, spline interpolation method, a partial derivative analysis and multivariate regression. The results indicated a negative trend in all the analysis periods (except spring) of the past 54 years of which only summer and the entire year were statistically significant (p < 0.01) with slopes of -1.09 and -1.30 mm·a-1 respectively. In contrast, a positive trend was observed in all four seasons and the entire year under the RCP 8.5 scenario, with the biggest increment equal to 1.36 mm·a-1 in summer and an annual increment of 3.37 mm·a-1. The spatial patterns of the seasonal and annual ET0 exhibited the lowest values in southeastern regions and the highest values in northeastern parts of Shandong Province, probably because of the combined effects of various meteorological variables over the past 54 years. Relative humidity (RH) together with solar radiation (RS) were detected to be the main climatic factors controlling the reduction of ET0 in summer, autumn, and the entire year on the 3H Plain. ET0 in spring was mainly sensitive to changes in RS and RH, whereas ET0 in winter was most sensitive to changes in wind speed (WS) and decreased due to declining RH. Under the future RCP 8.5 scenario, the annual ET0 distribution displays a rich spatial structure with a clear northeast-west gradient and anarea with low values in the southern regions, which is similarly detected in spring and summer. The most sensitive and primary controlling variables with respect to the increment of future ET0 are in the first place RS and then mean temperature in spring, while turn to be mean temperature and then RS in summer. In autumn, future ET0 is most sensitive to RH changes. WS and RH are the controlling variables for ET0 in winter. Annual future ET0 is most sensitive to RH changes and accordingly RS is responsible for the predicted increment of the annual ET0. Better understanding of current and future spatiotemporal patterns of ET0 and of the regional response of ET0 to climate change can contribute to the establishment of a policy to realize a more efficient use of water resources and a sustainable agricultural production in the 3H Plain. [less ▲]

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See detailImpact of poplar trees on the soil water dynamics of a maize field in West-Flanders
Coussement, Tom; Janssens, Pieter; Elsen, Annemie et al

Conference (2017, February 15)

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See detailCharacterization of stony soils' hydraulic conductivity using laboratory and numerical experiments
Beckers, Eléonore ULiege; Pichault, Mathieu; Pansak, Wanwisa et al

in SOIL (2016), 2

Determining soil hydraulic properties is of major concern in various fields of study. Although stony soils are widespread across the globe, most studies deal with gravel-free soils, so that the literature ... [more ▼]

Determining soil hydraulic properties is of major concern in various fields of study. Although stony soils are widespread across the globe, most studies deal with gravel-free soils, so that the literature describing the impact of stones on the hydraulic conductivity of a soil is still rather scarce. Most frequently, models characterizing the saturated hydraulic conductivity of stony soils assume that the only effect of rock fragments is to reduce the volume available for water flow, and therefore they predict a decrease in hydraulic conductivity with an increasing stoniness. The objective of this study is to assess the effect of rock fragments on the saturated and unsaturated hydraulic conductivity. This was done by means of laboratory experiments and numerical simulations involving different amounts and types of coarse fragments. We compared our results with values predicted by the aforementioned predictive models. Our study suggests that it might be ill-founded to consider that stones only reduce the volume available for water flow. We pointed out several factors of the saturated hydraulic conductivity of stony soils that are not considered by these models. On the one hand, the shape and the size of inclusions may substantially affect the hydraulic conductivity. On the other hand, laboratory experiments show that an increasing stone content can counteract and even overcome the effect of a reduced volume in some cases: we observed an increase in saturated hydraulic conductivity with volume of inclusions. These differences are mainly important near to saturation. However, comparison of results from predictive models and our experiments in unsaturated conditions shows that models and data agree on a decrease in hydraulic conductivity with stone content, even though the experimental conditions did not allow testing for stone contents higher than 20 %. [less ▲]

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See detailDealing with crop rotation in agroforestry: the impact of shade on winter wheat and sugar beet growth and yield under belgium conditions
Artru, Sidonie ULiege; Garré, Sarah ULiege; Hiel, Marie-Pierre ULiege et al

in Book of Abstract- 3rd European Agroforestry Conference 2016 (2016, May)

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See detailAre crop models able to efficiently simulate crop growth under shade?
Artru, Sidonie ULiege; Dumont, Benjamin ULiege; Lassois, Ludivine ULiege et al

in Gosme, Marie (Ed.) 3rd European Agroforestry conference 2016 - Book of abstracts (2016, May)

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See detailAssessment of a design to monitor the influence of crop residue management on the dynamics of soil water content with ERT
Chelin, Marie ULiege; Hiel, Marie-Pierre ULiege; Hermans, Thomas ULiege et al

Poster (2016, April 21)

Choices related to crop residue management affect the soil structure. As a consequence, they may determinethe spatio-temporal dynamics of water content and eventually the crop yields. In order to better ... [more ▼]

Choices related to crop residue management affect the soil structure. As a consequence, they may determinethe spatio-temporal dynamics of water content and eventually the crop yields. In order to better understand the influence of these strategies on hydraulic processes occurring at the plot scale, we opted for the use electrical resistivity tomography (ERT). This approach presents the advantage to limit soil disturbance but is still faced to important challenges when applied in an agricultural field context. Especially changing soil-electrode contact has to be considered, as it can lead to bad quality data, especially for setups with small electrodes and small inter-electrode distance. The objective of this study was to test the efficiency of a high-resolution 3-D field measurement design to properly assess the dynamics of soil water content. ERT measurements were conducted in a Cutanic Siltic Luvisol in Gembloux, Belgium, on two plots of 2m^2 ploughed in Oct 2014 at a depth of 25 cm and sown with maize in April 2015. The plants were removed on one of the plots in order to obtain a bare soil reference. A grid of 98 surface stainless steel electrodes was layed-out on each plot and four sticks supporting each eight stainless steel electrodes were vertically inserted into the soil up to 1.20 m to get more detailed information in depth. The experiments were performed between Jul and Oct 2015, in order to get measurements both in dry and wet periods. For surface and borehole monitoring, a dipole-dipole array configuration including in-line and cross-line measurements was adopted. Normal and reciprocal measurements were performed systematically to assess the data quality: only the datasets with a mean reciprocal error lower than 3% were considered for the data inversion. This contribution will show the first inverted results showing the complexity of experimental design and data analysis for high-resolution, timelapse ERT in field conditions. Based on these results, we will draw conclusions about a minimal data set to be obtained in our upcoming field experiments. [less ▲]

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