Variability of earthworm-induced biopores and their hydrological effectiveness in space and time

Schneider, Anne-Kathrin; Hohenbrink, Tobias L.; Reck, Arne; Zangerlé, Anne; Schröder, Boris; Zehe, Erwin; Schaik, Loes van

doi:10.1016/j.pedobi.2018.09.001

Cited by 25 publications

(10 citation statements)

References 63 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the pfd, we assume a steady-state balance between gravity and dissipative energy loss at the macropore walls. This implies purely advective flow characterized by a flow velocity v which can be inferred from either tracer or infiltration experiments on macroporous soils as described by Shipitalo and Butt (1999), Weiler (2001) and Zehe and Blöschl (2004). The particle displacement in our pfd is described by Eq.…”

Section: Advective Flow In the Macroporesmentioning

confidence: 99%

“…earth worm burrows, channels from degraded plant roots or shrinkage cracks, and all of them are non-static in space or time (e.g. Blouin et al, 2013;Nadezhdina et al, 2010;Palm et al, 2012;van Schaik et al, 2014;Schneider et al, 2018). Especially in rural areas and in combination with agrochemicals, macropore flow can be a dominant control on stream-water and groundwater pollution (e.g.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Simulating preferential soil water flow and tracer transport using the Lagrangian Soil Water and Solute Transport Model

Sternagel

Loritz

Wilcke

et al. 2019

Hydrol. Earth Syst. Sci.

Self Cite

View full text Add to dashboard Cite

Abstract. We propose an alternative model concept to represent rainfall-driven soil water dynamics and especially preferential water flow and solute transport in the vadose zone. Our LAST-Model (Lagrangian Soil Water and Solute Transport) is based on a Lagrangian perspective of the movement of water particles (Zehe and Jackisch, 2016) carrying a solute mass through the subsurface which is separated into a soil matrix domain and a preferential flow domain. The preferential flow domain relies on observable field data like the average number of macropores of a given diameter, their hydraulic properties and their vertical length distribution. These data may be derived either from field observations or by inverse modelling using tracer data. Parameterization of the soil matrix domain requires soil hydraulic functions which determine the parameters of the water particle movement and particularly the distribution of flow velocities in different pore sizes. Infiltration into the matrix and the macropores depends on their respective moisture state, and subsequently macropores are gradually filled. Macropores and matrix interact through diffusive mixing of water and solutes between the two flow domains, which again depends on their water content and matric potential at the considered depths. The LAST-Model is evaluated using tracer profiles and macropore data obtained at four different study sites in the Weiherbach catchment in southern Germany and additionally compared against simulations using HYDRUS 1-D as a benchmark model. While both models show qual performance at two matrix-flow-dominated sites, simulations with LAST are in better accordance with the fingerprints of preferential flow at the two other sites compared to HYDRUS 1-D. These findings generally corroborate the feasibility of the model concept and particularly the implemented representation of macropore flow and macropore–matrix exchange. We thus conclude that the LAST-Model approach provides a useful and alternative framework for (a) simulating rainfall-driven soil water and solute dynamics and fingerprints of preferential flow as well as (b) linking model approaches and field experiments. We also suggest that the Lagrangian perspective offers promising opportunities to quantify water ages and to evaluate travel and residence times of water and solutes by a simple age tagging of particles entering and leaving the model domain.

show abstract

Section: Advective Flow In the Macroporesmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Simulating preferential soil water flow and tracer transport using the Lagrangian Soil Water and Solute Transport Model

Sternagel

Loritz

Wilcke

et al. 2019

Hydrol. Earth Syst. Sci.

Self Cite

View full text Add to dashboard Cite

show abstract

“…By contrast, the related gravity and matric potentials are intensive state variables and as such not additive in the sense specified above, nor can their changes be balanced. Thirdly, it can be used to define and explain hydrological similarity based on a thermodynamically meaningful combination of catchment characteristics Seibert et al, 2017;Loritz et al, 2018). Last but not least, one may test whether thermodynamic optimality provides, despite the fact that it is controversial, a means to test the recent proposition of Savenije and Hrachowitz (2017), stating that "Ecosystems control the hydrological functioning of the root zone in a way that it continuously optimizes the functions of infiltration, moisture retention and drainage of catchments".…”

Section: Thermodynamic Reasoning In Hydrology and Related Earth Sciencesmentioning

confidence: 99%

Energy states of soil water – a thermodynamic perspective on soil water dynamics and storage-controlled streamflow generation in different landscapes

Zehe

Loritz

Jackisch

et al. 2019

Hydrol. Earth Syst. Sci.

Self Cite

View full text Add to dashboard Cite

Abstract. The present study confirms that a thermodynamic perspective on soil water is well suited to distinguishing the typical interplay of gravity and capillarity controls on soil water dynamics in different landscapes. To this end, we express the driving matric and gravity potentials by their energetic counterparts and characterize soil water by its free energy state. The latter is the key to defining a new system characteristic determining the possible range of energy states of soil water, reflecting the joint influences of soil physical properties and height over nearest drainage (HAND) in a stratified manner. As this characteristic defines the possible range of energy states of soil water in the root zone, it also allows an instructive comparison of top soil water dynamics observed in two distinctly different landscapes. This is because the local thermodynamic equilibrium at a given HAND and the related equilibrium storage allow a subdivision of the possible free energy states into two different regimes. Wetting of the soil in local equilibrium implies that free energy of soil water becomes positive, which in turn implies that the soil is in a state of storage excess, while further drying of the soil leads to a negative free energy and a state of storage deficit. We show that during 1 hydrological year the energy states of soil water visit distinctly different parts of their respective energy state spaces. The two study areas compared here exhibit furthermore a threshold-like relation between the observed free energy of soil water in the riparian zone and observed streamflow, while the tipping points coincide with the local equilibrium state of zero free energy. We found that the emergence of a potential energy excess/storage excess in the riparian zone coincides with the onset of storage-controlled direct streamflow generation. While such threshold behaviour is not unusual, it is remarkable that the tipping point is consistent with the underlying theoretical basis.

show abstract

“…Indeed, soil biota require space and connectivity between pores to move through the soil, to forage for nutrients and/or carbon-based energy sources, water and living space (e.g., plant large roots and macrofauna such as earthworms, ants or termites). This can be achieved either by pushing aside soil aggregates or by ingesting soil (e.g., in earthworms), creating the so-called biopores that remain after roots death or the passage of fauna ( Schneider et al, 2018 ).…”

Section: Introductionmentioning

confidence: 99%

KEYLINK: towards a more integrative soil representation for inclusion in ecosystem scale models. I. review and model concept

Deckmyn

Flores

Mayer

et al. 2020

PeerJ

View full text Add to dashboard Cite

The relatively poor simulation of the below-ground processes is a severe drawback for many ecosystem models, especially when predicting responses to climate change and management. For a meaningful estimation of ecosystem production and the cycling of water, energy, nutrients and carbon, the integration of soil processes and the exchanges at the surface is crucial. It is increasingly recognized that soil biota play an important role in soil organic carbon and nutrient cycling, shaping soil structure and hydrological properties through their activity, and in water and nutrient uptake by plants through mycorrhizal processes. In this article, we review the main soil biological actors (microbiota, fauna and roots) and their effects on soil functioning. We review to what extent they have been included in soil models and propose which of them could be included in ecosystem models. We show that the model representation of the soil food web, the impact of soil ecosystem engineers on soil structure and the related effects on hydrology and soil organic matter (SOM) stabilization are key issues in improving ecosystem-scale soil representation in models. Finally, we describe a new core model concept (KEYLINK) that integrates insights from SOM models, structural models and food web models to simulate the living soil at an ecosystem scale.

show abstract

Variability of earthworm-induced biopores and their hydrological effectiveness in space and time

Cited by 25 publications

References 63 publications

Simulating preferential soil water flow and tracer transport using the Lagrangian Soil Water and Solute Transport Model

Simulating preferential soil water flow and tracer transport using the Lagrangian Soil Water and Solute Transport Model

Energy states of soil water – a thermodynamic perspective on soil water dynamics and storage-controlled streamflow generation in different landscapes

KEYLINK: towards a more integrative soil representation for inclusion in ecosystem scale models. I. review and model concept

Contact Info

Product

Resources

About