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The management of day-rich soils in agriculture is mainly dependent on their hydromechanical properties that govern their structural evolutions. These structural evolutions are commonly described along the shrinkage curves obtained in a laboratory. Nevertheless, the field survey needs tools of in situ investigations able to characterize the structural profile evolutions of soils through the seasons. This paper presents a method based on the cone penetration and resistivity measurement by penetrometer-salinometer coupling that was gauged in the West Marsh of the French Atlantic Coast. First, the parallel measurements of water and cone resistance ([Q.sub.d]) profiles in day dominant soils, characterized by very large ranges of water content (W), allows the calculation of a Perdock's-type equation that links the [Q.sub.d] profiles and the shrinkage curve of the day dominant material. Second, thanks to the homogeneity of mineralogy and cationic exchange capacity of the soil, the structure-resistivity relationship was gauged according to the Archie's law taking into account porosity ([phi]), saturation index of the soil (Sat), and the resistivity of the wetting fluid ([[rho].sub.w]). The vertical evolutions of structure, resistivity, and cone resistance can be represented in a crossed diagram showing the shrinkage curve--resistivity and [Q.sub.d] profile relationships. Finally; the structural profiles of soils can be modeled from the recorded resistivity and [Q.sub.d] profiles taking into account the [[rho].sub.w]. Abbreviations: e, void ratio;[Q.sub.d], cone resistance (MPa); Sat, saturation index (%); W, gravimetric water content (%); W1, liquidity limit (%); Wp, plasticity limit (%); Ws, shrinkage limit (%); [phi], porosity (%); [[rho].sub.s], soil resistivity ([OMEGA] m); [[rho].sub.w], wetting fluid resistivity ([OMEGA] m); [[gamma].sub.b], wet density (g [cm.sup.-3]); [[gamma].sub.s], real density of the clayey particles (g [cm.sup.-3]).

Modeling the shrinkage and subsidence of soils is generally based on the laboratory shrinkage curves established from liquid state to shrinkage limit, rarely exhibited in situ. We studied the vertical behavior of day-dominant soils from the Marais de l'Ouest (France) in the 20 to 100% water content range. The consolidation states were quantified by recording profiles of wet density ([[gamma].sub.b]) and gravimetric water content (W) down to the depth of 2.50 and 2.00 m in a sunflower (Helianthus annuus L.) field and a grassland, respectively. Under the evident surface consolidation, a paleosol was observed at 1.3-m depth in the sunflower field. The W profiles show two superimposed layers: in the upper layer, W increased from the shrinkage limit ([W.sub.s]) to the plasticity limit ([W.sub.p]), the W profiles bounded by the wet and dry season profiles; in the subjacent layer (100% > W > [W.sub.p]), the W profiles were quite constant. The depth of [W.sub.p] marks the end of the downward progression of the shrinkage cracks. The properties of shrinkage were established through drying stages on intact samples. In the [W.sub.s] to [W.sub.p] domain, the linearity of the volume-water content relation allows the modeling of the interseasonal volumetric distribution of the macro-porosity due to the shrinkage cracks. The preliminary model of porosity behavior proposed agrees with the two superimposed layers: the [W.sub.s] to [W.sub.p] domain characterized by isotropic shrinkage (shrinkage geometry factor r = 3), and the W > [W.sub.p] domain characterized by subsidence only (r = 1).

Crystalline erbium (Er)-doped zinc oxide thin films were grown by pulse-laser deposition and were analyzed by the complementary use of Rutherford backscattering spectroscopy, x-ray diffraction analysis, atomic force microscopy, and photoluminescence. The composition, structure, and surface morphology of films were studied, as a function of the growth conditions and Er-doping rate.

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