Journal ArticleDOI
A Conceptual Model of Soil Susceptibility to Macropore Flow
TLDR
In this paper, Vanclooster et al. proposed an approach to upscaling predictions from local-scale data based on the assumption that soil mapping units (soil series or associations, characterized by benchmark pedons, i.e., typical sequences of recognized soil horizons in a profi le) are characterized by information relevant to solute transport and can be considered as macroscopically homogeneous structural units.Abstract:
(shrinkage cracks, interaggregate voids, earthworm channels, and root holes) strongly infl u-ence water fl ow in structured soils and therefore patterns of solute displacement. Macropore fl ow increases the risk of leaching of surface-applied contaminants to groundwater, since infi ltrating water can be quickly channeled through only a very small fraction of the total pore volume, bypassing much of the adsorption and degradation capacity of the chemically and biologically reactive topsoil. Th e signifi cance of macropore fl ow has long been recog-nized (e.g., Th omas and Phillips, 1979), and in recent decades this has stimulated a major experimental research eff ort aimed at improving understanding of its causes, controlling factors, and consequences (Jarvis, 2007). Th is research eff ort has gone hand in hand with the development of many models that attempt to synthesize knowledge of the relevant processes in mathematical form (Gerke, 2006). Th ese models can be used as tools in research to test the limits of our understanding and generate new hypoth-eses, and as management tools to support policy development and decision making (Vanclooster et al., 2004).At well-investigated sites, input parameters to macropore fl ow models can be either directly measured or derived by calibra-tion against depth profi les of resident concentrations and solute breakthrough curves to further minimize prediction uncertainty (Larsbo and Jarvis, 2005). Many model users (e.g., agricultural advisors, water managers, and regulatory authorities), however, are also required to make predictions for less well characterized sites or at larger scales, for example, to map and quantify diff use pollution risks at farm, catchment, regional, and even national scales. Models that account for macropore fl ow must then be used predictively, without any direct measurements of input param-eters or site data for calibration, although it can be assumed that “soft” information in the form of soil and topographic maps and land use statistics will generally be available. Soil maps have long been used as a basis for catchment- and regional-scale vulnerabil-ity and risk assessments (Vanclooster et al., 2004). Th is approach to upscaling predictions from local-scale data is based on the assumption that soil mapping units (soil series or associations, characterized by benchmark pedons, i.e., typical sequences of recognized soil horizons in a profi le) are characterized by infor-mation relevant to solute transport and can be considered as macroscopically homogeneous structural units (e.g., Vogel and Roth, 2003; Vereecken et al., 2007). Th is assumption may beread more
Citations
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Journal ArticleDOI
Pedotransfer functions in Earth system science: challenges and perspectives
Kris Van Looy,Johan Bouma,Michael Herbst,John Koestel,Budiman Minasny,Umakant Mishra,Carsten Montzka,Attila Nemes,Yakov Pachepsky,José Padarian,Marcel G. Schaap,Brigitta Tóth,Brigitta Tóth,Anne Verhoef,Jan Vanderborght,Martine van der Ploeg,Lutz Weihermüller,Steffen Zacharias,Yonggen Zhang,Yonggen Zhang,Harry Vereecken +20 more
TL;DR: In this article, a review of the existing PTFs and new generation of PTF developed in the different disciplines of Earth system science is presented, emphasizing that PTF development has to go hand in hand with suitable extrapolation and upscaling techniques such that the PTF models correctly represent the spatial heterogeneity of soils.
Journal ArticleDOI
Understanding Preferential Flow in the Vadose Zone: Recent Advances and Future Prospects
TL;DR: In this paper, the authors review some of the more significant advances that have been made in the last decade in the study of preferential flow through the vadose zone as well as suggest some research needs in the coming years.
Journal ArticleDOI
Applicability of models to predict phosphorus losses in drained fields: a review.
David E. Radcliffe,D. Keith Reid,Karin Blombäck,Carl H. Bolster,Amy S. Collick,Zachary M. Easton,Wendy Francesconi,Daniel R. Fuka,Holger Johnsson,Kevin W. King,Mats Larsbo,Mohamed A. Youssef,Alisha S. Mulkey,Nathan O. Nelson,Kristian Persson,John J. Ramirez-Avila,Frank Schmieder,Douglas R. Smith +17 more
TL;DR: This review assesses the applicability of nine models to predict P loss in drainage waters and concludes that field experiments using a nested, paired research design are needed to improve P models for artificially drained fields.
Journal ArticleDOI
Pesticide fate in soil-sediment-water environment in relation to contamination preventing actions
TL;DR: In this article, the authors highlighted the potential risk posed by pesticides to the environment and the unequivocal presence of pesticide residues in soil, sediment and water samples has raised public and scientific awareness.
Book ChapterDOI
Addressing Two Bottlenecks to Advance the Understanding of Preferential Flow in Soils
Li Guo,Henry Lin,Henry Lin +2 more
TL;DR: In this paper, a framework of six key categories of controls is developed to assess the susceptibility of various soils to preferential flow, and the mechanisms of different controlling factors affecting preferential flow are discussed using the proposed framework.
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