A Soil Classification System for Describing Water and Chemical Transport

Smith, Bill; Phillips, R. E.; Scott, H. D.; Nortcliff, Stephen

doi:10.1097/00010694-199311000-00003

Cited by 71 publications

(37 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The Esto pedon fits in the general description of class 4 (preferential or macropore flow, mostly along tertiary ped faces), even though no clear tertiary peds were observed. The Faceville series is indicated to be in class 3 (uniform or Darcian type flow, piston type displacement) [Quisenberry et al, 1993]. However, the Faceville pedon described here does not fit in …”

Section: Structure Development and Preferential Flowmentioning

confidence: 89%

Soil structure development and preferential solute flow

Vervoort¹,

Radcliffe²,

West³

1999

Water Resources Research

105

View full text Add to dashboard Cite

Abstract. Soil structure and preferential flow are thought to be highly related, but quantification of this relationship has remained problematic. A combination of experiments on two soils at local and field scale was used to study the relationships between the degree of structural development, saturated conductivities Ks, moisture release, breakthrough parameters, and observations of preferential flow at the field scale. The convection dispersion equation and mobile-immobile model were fitted to breakthrough curves, and flow channels were stained with dye. Well-developed structure was associated with high dispersivities, a high coefficient of variation of Ks, and low mobile water contents, low exchange coefficients, and a low dyed area. Field-scale observations matched the differences in structure and preferential flow parameters observed at the local scales. Local-scale preferential flow appeared to highly influence field-scale solute transport, indicating that this is an important local-scale process which is not dampened at the field scale. A conceptual model of subsoil structural development was expanded with physical parameters matching the structural development stage to predict the likelihood of preferential flow on the basis of the saturation regime of the horizon or pedon. IntroductionSoil structure is important in many soil processes, especially in fine-textured soils. Surface soil structure and aggregate stability are important factors in erosion control in that structural It is even more difficult to quantify soil structure. Aggregate stability has been used as a measure of soil structure, but this is usually confined to soil surface measurements [Kemper and Rosenau, 1986]

show abstract

Section: Structure Development and Preferential Flowmentioning

confidence: 89%

Soil structure development and preferential solute flow

Vervoort¹,

Radcliffe²,

West³

1999

Water Resources Research

105

View full text Add to dashboard Cite

show abstract

“…In soils with compound pedality, Lin et al (1999a) found that primary pedality had limited impact on infiltration at water potential of > −0.03 m. Quisenberry et al (1993) and Nortcliff et al (1994) also reported that in a soil with both primary and secondary peds, preferential flow occurred mostly along secondary ped faces.…”

Section: Aggregate and Macropore Scalementioning

confidence: 96%

Hydropedology and Surface/Subsurface Runoff Processes

Lin

Brooks

McDaniel

et al. 2005

Encyclopedia of Hydrological Sciences

View full text Add to dashboard Cite

The role of soils has long been recognized as critical to rainfall–runoff processes in watersheds. Hydropedology is an emerging interdisciplinary field that integrates pedology, hydrology, geomorphology, and other related bio‐ and geosciences to study interactive pedologic and hydrologic processes and the landscape–soil–hydrology relationships across space and time. This article presents an overview of hydropedology's contributions to the understanding and modeling of surface/subsurface runoff processes, especially the diagnosis of soil features that can help answer “why‐type” questions in watershed hydrology and the ubiquitous nature of preferential flow and its networks. We highlight two bottlenecks for advancing watershed hydrology and hydropedology: a conceptual bottleneck of modeling subsurface preferential flow networks and a technological bottleneck of nondestructively mapping or imaging subsurface architecture. Quantification of “soil architecture” at various scales and the identification of “hydropedologic functional units” in different landscapes offer promising potentials to advance hydrologic modeling. We present the information of linking surface/subsurface runoff processes to pedologic understanding at three scales of microscopic (macropores and aggregates), mesoscopic (horizons and pedons), and macroscopic (hillslopes and catchments) levels. Various examples from the literature are synthesized to illustrate the key points. Further research needs are suggested in the end.

show abstract

“…This is similar to the clay content needed for the formation of stable soil aggregates (Horn et al, 1994) and may also reflect an absence of biopores in soils with less than 9 % clay, since both roots and earthworms generally avoid coarse single-grain soils. Notably, Quisenberry et al (1993) used a clay content of 8 % as the first criterion for a decision tree for classifying water and solute transport characteristics of soil, although they only presented 11 measurements to support the choice of this threshold. Our study confirms their conjecture.…”

Section: Figmentioning

confidence: 99%

Meta-analysis of the effects of soil properties, site factors and experimental conditions on solute transport

Koestel

Moeys

Jarvis

2012

Hydrol. Earth Syst. Sci.

View full text Add to dashboard Cite

Abstract. Preferential flow is a widespread phenomenon that is known to strongly affect solute transport in soil, but our understanding and knowledge is still poor of the site factors and soil properties that promote it. To investigate these relationships, we assembled a database from the peer-reviewed literature containing information on 733 breakthrough curve experiments under steady-state flow conditions. Most of the collected experiments (585 of the 733 datasets) had been conducted on undisturbed soil columns, although some experiments on repacked soil, clean sands, and glass beads were also included. In addition to the apparent dispersivity, we focused our attention on three indicators of preferential solute transport: namely the 5 %-arrival time, the holdback factor, and the ratio of piston-flow and average transport velocities. Our results suggest that, in contrast to the 5 %-arrival time and the holdback factor, the piston-flow to transport velocity ratio is not related to preferential macropore transport but rather to the exclusion or retardation of the applied tracer. Confirming that the apparent longitudinal dispersivity is positively correlated with the travel distance of the tracer, our results also illustrate that this relationship is refined if the normalized 5 %-tracer arrival time is also taken into account. In particular, we found that the degree of preferential solute transport increases with apparent dispersivity and decreases with travel distance. A similar but weaker relationship was observed between apparent dispersivity, 5 %-tracer arrival time, and lateral observation scale, such that the degree of preferential transport increases with lateral observation scale. However, we also found that the travel distance and the lateral observation scale in the investigated dataset are correlated, which makes it difficult to distinguish their influence on these transport characteristics. We also found that the strength of preferential transport increased at larger flow rates and water saturations, which suggests that macropore flow was a more important flow mechanism than heterogeneous flow in the soil matrix. Nevertheless, our data show that heterogeneous flow in the soil matrix also occasionally leads to strong preferential transport. Furthermore, we show that preferential solute transport under steady-state flow depends on soil texture in a threshold-like manner: moderate to strong preferential transport was found to occur only for undisturbed soils that contain more than 8 % clay. Preferential flow characteristics were also absent for columns filled with glass beads, clean sands, or sieved soil. No clear effect of land use on the pattern of solute transport could be discerned, probably because the available dataset was too small and too strongly affected by cross-correlations with experimental conditions. Our results suggest that, in developing pedotransfer functions for solute transport properties of soils, it is critically important to account for travel distance, lateral observation scale, an...

show abstract

A Soil Classification System for Describing Water and Chemical Transport

Cited by 71 publications

References 0 publications

Soil structure development and preferential solute flow

Soil structure development and preferential solute flow

Hydropedology and Surface/Subsurface Runoff Processes

Meta-analysis of the effects of soil properties, site factors and experimental conditions on solute transport

Contact Info

Product

Resources

About