Self-potentials in partially saturated media: the importance of explicit modeling of electrode effects

Self-potential (SP) data are of interest to vadose zone hydrology because of their direct sensitivity to water flow and ionic transport. There is unfortunately little consensus in the literature about how to best model SP data under partially saturated conditions, and different approaches (often supported by one laboratory data set alone) have been proposed. We argue that this lack of agreement can largely be traced to electrode effects that have not been properly taken into account. A series of drainage and imbibition experiments were considered in which we found that previously proposed approaches to remove electrode effects were unlikely to provide adequate corrections. Instead, we explicitly modeled the electrode effects together with classical SP contributions using a flow and transport model. The simulated data agreed overall with the observed SP signals and allowed decomposing the different signal contributions to analyze them separately. After reviewing other published experimental data, we suggest that most of them include electrode effects that have not been properly taken into account. Our results suggest that previously presented SP theory works well when considering the modeling uncertainties presently associated with electrode effects. Additional work is warranted to not only develop suitable electrodes for laboratory experiments but also to assure that associated electrode effects that appear inevitable in longer term experiments are predictable, so that they can be incorporated into the modeling framework.

Le paysan instruit sur le serment civique ou Instruction familière, dans laquelle on fait connoître comment & pourquoi la nouvelle Constitution détruit la religion ([Reprod.])

Collection : Les archives de la Révolution française ; 8.1306

Instruction pressante sur la Constitution civile du clergé ([Reprod.])

Collection : Les archives de la Révolution française ; 8.52

Examen de l'instruction de l'Assemblée nationale sur la Constitution du clergé ([Reprod.])

Collection : Les archives de la Révolution française ; 8.584

Commentaire sur l'instruction de l'Assemblée nationale sur l'organisation civile du clergé ([Reprod.])

Collection : Les archives de la Révolution française ; 8.585

L'instruction de l'Assemblée nationale, sur l'organisation civile du clergé, arguée de mauvaise foi, d'inconséquence et d'injustice ([Reprod.])

Collection : Les archives de la Révolution française ; 8.64

Seconde instruction pressante sur la Constitution civile du clergé ([Reprod.])

Collection : Les archives de la Révolution française ; 8.53

Apologie du clergé de France ou commentaire raisonné, sur l'instruction pastorale de l'assemblée nationale, concernant l'organisation civile du clergé ([Reprod.]) / [par M. l'abbé Blandin]

Collection : Les archives de la Révolution française ; 8.534

Epître à M. Lamourette, se disant évêque de Rhône-et-Loire, métropolitain du sud-est sur son instruction pastorale et doctrinale du 16 juillet 1791 ([Reprod.]) / [par M. A. Guillon]

Collection : Les archives de la Révolution française ; 8.1417

Mémoire pour servir d'instruction aux commis à la recette du droit de centième denier de tous les offices de judicature, police, finances, et autres offices royaux, pour l'année 1773, en exécution de l'édit du mois de février 1771, et de l'arrêt du Conseil du 6 juillet 1772

[Acte. 1772]

quantiNemo: an individual-based program to simulate quantitative traits with explicit genetic architecture in a dynamic metapopulation.

quantiNemo is an individual-based, genetically explicit stochastic simulation program. It was developed to investigate the effects of selection, mutation, recombination and drift on quantitative traits with varying architectures in structured populations connected by migration and located in a heterogeneous habitat. quantiNemo is highly flexible at various levels: population, selection, trait(s) architecture, genetic map for QTL and/or markers, environment, demography, mating system, etc. quantiNemo is coded in C++ using an object-oriented approach and runs on any computer platform. Availability: Executables for several platforms, user's manual, and source code are freely available under the GNU General Public License at http://www2.unil.ch/popgen/softwares/quantinemo.