A brief review of soil water, solute transport and regionalized variable analysis

Abstract

We initially review basic concepts of the forces acting on soil water, soil water potential and soil water retention, and equations to describe soil water movement under water-saturated and unsaturated conditions. Processes of infiltration, evaporation and redistribution of water will be presented for simple initial and boundary conditions occurring within homogeneous soil columns. Next we consider the physical, chemical and biological processes within a soil profile that distribute, dilute or concentrate solute species within the liquid phase of a soil The relative concentration of solutes in the liquid phase governs not only the retention and transport of water within soils but also contributes to our understanding of managing the quality of water within soils and that moving below the recall of plant roots deeper into the vadose zone. A complete set of references about this subject is available in Kutílek & Nielsen (1994). In the last section we recall the differences between classical statistical concepts and those that utilize the coordinates of space and time at which state variables across the landscape are observed. Our presentation win cover the basic ideas about autocorrelation, crosscorrelation, applied time series analyses, state space analyses and similar techniques currently being used to enhance field research and investigations of land and water management.

Water infiltration post-liquid dairy manure application in no-till Oxisol of Southern Brazil

“…1a), when the initial soilwater content is low, infiltration rate starts with high values decreasing gradually to a final constant rate (Jury et al, 1991;Nielsen et al, 1997). In 98 of 120 field tests (Table 4), infiltration followed the typical curve; however, 22 of 120 field tests did not follow the typical infiltration curve and were considered anomalous (Table 4).…”

Equitable transform applied to phenology and temperature in a changing climate: Scaling to maintain individuality

“…This is similar to how the Boltzmann transformation is used in soil science to transform various soil water content distributions to a reference soil distribution (Nielsen et al. ). We cannot emphasize enough that although we use the variables x and t frequently in this paper, they represent arbitrary variables and are in no way limited to the conventional associations of spatial and temporal coordinates.…”

“…These processes are also used extensively to model the transport of water through different soil types (Nielsen et al. , Timm et al. , Reichardt et al.…”

“…The ratio, f = x/t 1/2, is the Boltzmann transformation that is used to make soil profiles essentially equivalent to each other (Nielsen et al. ). More generally, this transformation is used to simplify a differential equation in two variables, x and t , to one involving only a single variable f .…”

Solute Transport in Soils: An Algorithmic Approach

“…Several detailed review papers on the subject have been published (Biggar and Nielsen 1967;Addiscott and Wagenet 1985;Nielsen et al 1986;van Genuchten and Jury 1987;Vachaud et al 1988;Kutílek and Nielsen 1994;Nielsen et al 1997).…”