Search results for "Infiltration"
showing 10 items of 291 documents
A Check of Water Drop Impact Effects on Surface Soil Saturated Hydraulic Conductivity
2020
The post-tillage dynamics of the surface soil saturated hydraulic conductivity, Ks, was studied at the Masse experimental station (central Italy, silty-clay-loam soil). A sequence of experiments was performed by rainfall simulation on two replicated micro-plots (width 1 m, length 0.92 m, slope 16%) established on bare soil. Each high-intensity rainfall simulation was preceded by a low-intensity wetting phase. The soil water content, w, was measured before wetting and both before and after simulation. Runoff was measured at 5 min intervals. The infiltration rate was calculated as the difference between rainfall intensity and runoff rate. Finally, Ks was assumed to be equal to the infiltratio…
Comparing Beerkan infiltration tests with rainfall simulation experiments for hydraulic characterization of a sandy-loam soil
2017
[EN] Saturated soil hydraulic conductivity, K-s, data collected by ponding infiltrometer methods and usual experimental procedures could be unusable for interpreting field hydrological processes and particularly rainfall infiltration. The K-s values determined by an infiltrometer experiment carried out by applying water at a relatively large distance from the soil surface could however be more appropriate to explain surface runoff generation phenomena during intense rainfall events. In this study, a link between rainfall simulation and ponding infiltrometer experiments was established for a sandy-loam soil. The height of water pouring for the infiltrometer run was chosen, establishing a sim…
Run duration effects on the hydrodynamic properties of a loam soil estimated by steady-state infiltration methods
2020
Steady-state methods for the analysis of single-ring infiltration data are commonly applied. However, the duration of an infiltrometer experiment is often established quite subjectively based on the assumption that in general infiltration stabilizes rather quickly in the field. For a loam soil, the effect of the duration of a beerkan run on sorptivity, S, and saturated hydraulic conductivity, Ks, was tested by using the BEST (Beerkan Estimation of Soil Transfer parameters)-steady method and SSBI (Steady version of the Simplified method based on a Beerkan Infiltration run) method for data analysis. The standard experiment, based on a total of 15 water volumes each establishing an initial pon…
On Infiltration and Infiltration Characteristic Times
2022
In his seminal paper on the solution of the infiltration equation, Philip (1969), https://doi.org/10.1016/b978-1-4831-9936-8.50010-6 proposed a gravity time, tgrav, to estimate practical convergence time and the time domain validity of his infinite time series expansion, TSE, for describing the transient state. The parameter tgrav refers to a point in time where infiltration is dominated equally by capillarity and gravity as derived from the first two (dominant) terms of the TSE. Evidence suggests that applicability of the truncated two-term equation of Philip has a time limit requiring higher-order TSE terms to better describe the infiltration process for times exceeding that limit. Since …
Multiple Non-linear Reservoirs to Model Water Balance Components in Sandy Soils
2023
In the hydrologic literature, to model water flow in unsaturated soils, the Richards equation is usually applied, allowing the main components of the hydrologic cycle, as rainfall partitioning into surface runoff and infiltration, to be determined. The Richards equation is highly nonlinear, making very challenging to derive analytical solutions. Recently, for constant rainfall intensity, under the simplified hypothesis of gravity-driven infiltration, and by assuming a capacitance framework, a simplified solution of the Richards equation that considers the Brooks and Corey hydraulic conductivity function was suggested. By maintaining the assumption that the infiltration process is dominated …
Simplified estimation of field saturated soil hydraulic conductivity from ponded infiltration data
2013
Simple and reasonably rapid experiments are desirable to conduct a spatially distributed determination of field-saturated soil hydraulic conductivity, Kfs, that is a highly variable soil property. Bagarello et al. (2012) recently developed a simplified approach to estimate Kfs that is based on a ponded field infiltration experiment. A cylinder is inserted to a short depth into the soil, so to produce a minimal disturbance of the porous medium, and the infiltration time of a few small volumes of water repeatedly applied at the surface of the confined soil is measured. Calculating Kfs needs to determine the slope of the linearized cumulative infiltration vs. time relationship, the ring radius…
TERAPIA INFILTRATIVA INTRA-ARTICOLARE ASSOCIATA A MESALAZINA E PROBIOTICI NEL TRATTAMENTO DELL'ARTRITE NEL PAZIENTE CON MALATTIA INFIAMMATORIA CRONIC…
2015
L'artrite secondaria a malattia infiammatoria cronica intestinale può essere presente parecchi anni prima della diagnosi oppure manifestarsi come una vera complicanza.
Co-morbidities in patients with hip osteoarthritis and treated with ecoguided infiltrations of Hyaluronic acid: study of the effectiveness of the tre…
2014
The effectiveness of eco-guided infiltrations with high molecular weight associated with administration of oral chondroprotective supplements in oste…
2012
Osteoarthritis does not mean a degenerative articular process only but a pathologic expression of wear, inflammation and immunological imbalance of the joints. Our study has the aim to demonstrate the effectiveness of eco-guidate infiltrations with high molecular weight associated with administration of oral chondroprotective supplements (glucosamine solfate, chondroitin sulphate, hydrolyzed collagen type II, hyaluronic acid and L carnitine fumarate) in comparison with the only treatment with ecoguided infiltrations with hyaluronic acid in patients suffering from primary osteoarthiritis of the hip.
Sistema di Controllo Interno e prevenzione delle infiltrazioni della criminalità organizzata
2019
L’intensificarsi della diffusione delle infiltrazioni della criminalità organizzata in molteplici settori rende sempre più complessa per le aziende operanti con la pubblica amministrazione, la verifica dell’affidabilità, non solo economico-patrimoniale, dei soggetti (es., partner, clienti, fornitori) con i quali interagire. L’assenza di efficaci strumenti di prevenzione e contrastato dei tentativi di infiltrazioni della criminalità organizzata nella gestione aziendale può dar luogo a sanzioni interdittive, compromettendo in modo irreversibile l’immagine e il processo di creazione di valore e tutela degli stakeholders. Muovendo da tali presupposti, il presente lavoro è teso a verificare se i…