Modeling rainfall-driven transport of Glyphosate in the vadose zone of two experimental sites in North-East Italy

A vertical one-dimensional analysis of infiltration processes and mobility of a tracer (potassium bromide) and a glyphosate-based herbicide, both subjected to hydrological forcing, was performed. Glyphosate is a widespread herbicide whose potential harmfulness and mobility under hydrological forcing have not been fully understood yet. Here, the spatio-temporal evolution of the two compounds was monitored for one year in two experimental sites (Settolo - Valdobbiadene, Colnù - Conegliano), located within the production area of the Prosecco wine (Treviso, Italy). In each experimental site the activities were carried out on two 25 m2 plots located at distances of 50-100 m from each other. The interpretative analyses considered rainwater infiltration as the driving mechanism of the herbicide transport and allowed us to obtain the calibration of a one-dimensional hydrologic model in each monitored plot. Different scenarios of the tracer evolution were simulated considering the pedologic properties of the shallower soil layers, the status of the plant coverage and of the root apparati, leading to a satisfactory reproduction of the observations in both the experimental sites. Modeling the mobility of the herbicide, considering also the degradation to its metabolite AMPA, proved to be more challenging, due to the tendency of glyphosate to be adsorbed to the soil matrix rather than be dissolved in water and transported toward deeper soil layers. Nevertheless, the analysis of model results for tracer and herbicide, compared with in situ observations, suggests that the transport of the glyphosate can take place even when it is adsorbed to the soil, through the movement, triggered by intense precipitation events, of microscopic soil particles within preferential flow paths

The pandemic within the pandemic: the surge of neuropsychological disorders in Italian children during the COVID-19 era

Background: Quarantine and isolation measures during COVID-19 pandemic may have caused additional stress and challenged the mental health of the youth. Aim of the study is to investigate the COVID-19 pandemic impact on neuropsychological disorders (NPD) of Italian children and adolescents to provide general pediatric recommendations. Material and methods: A retrospective multicenter observational study was planned by the Italian Pediatric Society (SIP) to explore the impact of COVID-19 on the access of children to pediatric Emergency Departments (pED) for the evaluation of neuropsychological symptoms, collecting the classification codes of diagnoses between March 1, 2019 and March 2, 2021. The period study was split into two sub-periods: a pre COVID-19 period (from March 1 2019 to March 1, 2020) and a COVID-19 period (from March 2, 2020 to March 2, 2021). As additional information, data on NPD hospitalizations in any pediatric department of the involved centers were recorded. Results: During the study period, a total of 533,318 children were admitted to the pED involved in the study. Despite a 48.2% decline of pED admissions, there was a significant increase (83.1%) in patient admissions for NPD. The most frequent NPD conditions which increased during the COVID-19 pandemic were suicidal ideation (+ 147%), depression (+ 115%), eating disorder (+ 78.4%), and psychosis (+ 17.2%). During the pandemic period, a 39.5% increase in NPD hospitalizations was observed as well. The NPD disorders that mostly required hospitalizations were suicidal ideation (+ 134%), depression (+ 41.4%), eating disorder (+ 31.4%), and drug abuse (+ 26.7%). COVID-19 pandemic had a major impact on children's health, mainly on their NPD development. Neuropsychological assessment should be required at the primary level, in the pediatrician's office, to facilitate early capture of the sign of impairment and provide an adequate treatment. Conclusion: SIP underlines the psychological consequences of COVID 19 pandemic on the youngest and recommends an early identification of NPD in the pediatric population to avoid other serious consequences for children's physical and mental health

Preferential solute transport under variably saturated conditions in a silty loam soil: Is the shallow water table a driving factor?

A shallow water table might enhance preferential solute movement by modifying both the water flow and solute dynamics. In this study, we estimated soil hydraulic and solute transport parameters through a tracer experiment in lysimeters comparing different water table levels. In a set-up of 12 lysimeters, the bottom boundary condition was set as a water table depth of 120 cm, or 60 cm, or as free drainage. A tracer solution of bromide (250 mg l 1, 40 mm) was added to each lysimeter and soil water was sampled with suction cups at different depths for the following 174 days. Soil water content and matric potential were monitored using TDR probes and electronic tensiometers at the same depths. Soil hydraulic and solute transport parameters in different soil layers were estimated by inverse modeling using HYDRUS 1D. Soil hydraulic parameters were estimated from the Mualemvan Genuchten equations, while both the advection\u2013dispersion (ADE) and physical non-equilibrium mobileimmobile water (MIM) models were used to describe the solute transport. Moreover, the soil pore network was analyzed by means of 3D X-ray microtomography. Results showed different solute dynamics between contrasting water table managements. With free drainage, solute in the immobile domain was negligible, and its transport was fully associated with the mobile water flow. In contrast, a shallow water table affected the tracer transport, by modifying a) the soil pore network, with an increase of the macropores and a reduction of the pore connectivity; b) the flow field, with an increase of immobile water and a reduction of \u3b1MIM, indicating slow exchange between mobile and immobile regions, in turn promoting preferential pathways. Hence, groundwater pollution might be worsened by preferential solute transport of agrochemicals occurring with shallow water table conditions

Assessing submarine slope stability from sediment properties in the Gulf of Cadiz, offshore Portugal

American Geophysical Union (AGU) Fall Meeting, 9-13 December 2019, San FranciscoThe development of excess pore pressure in soft marine sediments is a major pre-conditioning factor for slope instabilities. Basin analysis and hydrogeological models are often the only options to evaluate present-day overpressure conditions as well as their evolution through time. We describe a workflow that integrates measured geotechnical data and interpreted stratigraphy into finite element hydrogeological models to obtain the computed excess pore pressure and slope stability history of the Marques de Pombal area, located offshore Portugal. The hanging wall of the Marques de Pombal fault displays multiple slope failures. The location of the mass transport complex at the bottom of the Marques de Pombal active fault suggests earthquake shaking as the most probable triggering mechanism for local mass wasting events. Nevertheless, the role of preconditioning factors such as pore pressure development needs to be weighed against seismic shaking. We integrated the stratigraphic model revealed by IODP Well 339-U1391, drilled approximately 50 km away from the study area, with new geophysical data and gravity cores collected from the INSIGHT cruises conducted by ICM – CSIC in 2018 and 2019. We measured geotechnical properties from the sediments collected in the study area, such as initial porosity, compressibility and permeability, and assigned them to 2D finite element slope stability models by using commercial geotechnical software, in order to obtain the computed excess pore pressure and slope stability history for the Marques de Pombal area. Besides providing a new approach to define regional hydrogeological models with measured sediment properties, our models’ results show mid-to-high overpressure ratio (up to 0.4) influencing the stability of the slope from the Middle Pleistocene until the present day. By comparing the ages of the deposits with the computed history of the slope’s stability, we are able to constrain the minimum earthquake magnitudes required to induce past slope failures and make inferences about potential future one

Assessing submarine slope stability from sediment properties in the Gulf of Cadiz, offshore Portugal

American Geophysical Union (AGU) Fall Meeting, 9-13 December 2019, San FranciscoThe development of excess pore pressure in soft marine sediments is a major pre-conditioning factor for slope instabilities. Basin analysis and hydrogeological models are often the only options to evaluate present-day overpressure conditions as well as their evolution through time. We describe a workflow that integrates measured geotechnical data and interpreted stratigraphy into finite element hydrogeological models to obtain the computed excess pore pressure and slope stability history of the Marques de Pombal area, located offshore Portugal. The hanging wall of the Marques de Pombal fault displays multiple slope failures. The location of the mass transport complex at the bottom of the Marques de Pombal active fault suggests earthquake shaking as the most probable triggering mechanism for local mass wasting events. Nevertheless, the role of preconditioning factors such as pore pressure development needs to be weighed against seismic shaking. We integrated the stratigraphic model revealed by IODP Well 339-U1391, drilled approximately 50 km away from the study area, with new geophysical data and gravity cores collected from the INSIGHT cruises conducted by ICM – CSIC in 2018 and 2019. We measured geotechnical properties from the sediments collected in the study area, such as initial porosity, compressibility and permeability, and assigned them to 2D finite element slope stability models by using commercial geotechnical software, in order to obtain the computed excess pore pressure and slope stability history for the Marques de Pombal area. Besides providing a new approach to define regional hydrogeological models with measured sediment properties, our models’ results show mid-to-high overpressure ratio (up to 0.4) influencing the stability of the slope from the Middle Pleistocene until the present day. By comparing the ages of the deposits with the computed history of the slope’s stability, we are able to constrain the minimum earthquake magnitudes required to induce past slope failures and make inferences about potential future one

Assessing submarine slope stability from sediment properties in the Gulf of Cadiz, offshore Portugal

American Geophysical Union (AGU) Fall Meeting, 9-13 December 2019, San FranciscoThe development of excess pore pressure in soft marine sediments is a major pre-conditioning factor for slope instabilities. Basin analysis and hydrogeological models are often the only options to evaluate present-day overpressure conditions as well as their evolution through time. We describe a workflow that integrates measured geotechnical data and interpreted stratigraphy into finite element hydrogeological models to obtain the computed excess pore pressure and slope stability history of the Marques de Pombal area, located offshore Portugal. The hanging wall of the Marques de Pombal fault displays multiple slope failures. The location of the mass transport complex at the bottom of the Marques de Pombal active fault suggests earthquake shaking as the most probable triggering mechanism for local mass wasting events. Nevertheless, the role of preconditioning factors such as pore pressure development needs to be weighed against seismic shaking. We integrated the stratigraphic model revealed by IODP Well 339-U1391, drilled approximately 50 km away from the study area, with new geophysical data and gravity cores collected from the INSIGHT cruises conducted by ICM – CSIC in 2018 and 2019. We measured geotechnical properties from the sediments collected in the study area, such as initial porosity, compressibility and permeability, and assigned them to 2D finite element slope stability models by using commercial geotechnical software, in order to obtain the computed excess pore pressure and slope stability history for the Marques de Pombal area. Besides providing a new approach to define regional hydrogeological models with measured sediment properties, our models’ results show mid-to-high overpressure ratio (up to 0.4) influencing the stability of the slope from the Middle Pleistocene until the present day. By comparing the ages of the deposits with the computed history of the slope’s stability, we are able to constrain the minimum earthquake magnitudes required to induce past slope failures and make inferences about potential future one

Glyphosate and AMPA have low mobility through different soil profiles of the prosecco wine production area: A monitoring study in north-eastern Italy

Contamination of the environment by glyphosate (GLP) and its metabolite aminomethylphosphonic acid (AMPA) is still of major concern worldwide due to specific interactions among these molecules and soil and water. Two monitoring sites were established in the Prosecco wine production area (Conegliano and Valdobbiadene) in northeastern Italy, which has been included in UNESCO's World Heritage List since 2019. The study aims to increase the knowledge about GLP dynamics in this area where it has been intensively used by farmers and the potential risk for groundwater pollution is still debated. Each site was equipped with two soil-water monitoring stations consisting of multisensor soil probes and suction cups at three soil depths (10, 30, and 70 cm). Soil and water were sampled for 10 and 6 months, respectively, and analyzed for GLP and AMPA concentrations, for a total of 242 samples to describe their vertical movement and dissipation dynamics. Soil properties, in particular, the different forms of Fe and Al oxide contents, and Freundlich adsorption coefficients were quantified along the soil profile. First attempts showed that glyphosate dissipation time was 36 ± 8 days in Conegliano and Valdobbiadene soils and fully completed in both after 6 months. In contrast, AMPA dissipation dynamic -first described by an original equation-was longer than that of GLP and fully dissipated after almost 300 days. GLP showed a strong binding affinity with clay and Fe and Al chelated to soil organic matter, which likely acted as cation bridges and in turn led to low GLP mobility. GLP and AMPA were mostly detected after heavy rainfall events at 70 cm depth, likely bypassing the porous matrix of the intermediate layers