Conrad Jackisch- PhD
- Junior Professor at TU Bergakademie Freiberg
Conrad Jackisch
- PhD
- Junior Professor at TU Bergakademie Freiberg
About
59
Publications
19,212
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1,007
Citations
Introduction
Current institution
Additional affiliations
November 2018 - present
Position
- PostDoc Position
Description
- Project Risk, Uncertainty and Insurance under Climate Change. Coastal Land Management on the German North Sea (RUINS)
November 2015 - May 2018
October 2008 - September 2011
Publications
Publications (59)
We conducted a PUB (predictions in ungauged basins) experiment looking at hydrology and crop dynamics in the semi-arid rural Mod catchment in India. The experiment was motivated by the aims (a) to develop a coupled eco-hydrological model capable of analysing land-use strategies concerning crop water need, erosion protection, crop yield and resistiv...
According to Dooge (1986) intermediate-scale catchments are systems of organized complexity, being too organized and yet too small to be characterized on a statisti-cal/conceptual basis, but too large and too heterogeneous to be characterized in a deterministic manner. A key require-ment for building structurally adequate models precisely for this...
Modelling hydrological systems is dominated by an Eulerian
representation of storages and their transitions. At certain scales and
under preferential structures, this successful simplification proves
insufficient for a physical description of the subsurface flow
processes. We propose a Lagrangian representation of infiltration and
percolation, wher...
Hydro-pedotransfer functions (PTFs) relate easy-to-measure and readily available soil information to soil hydraulic properties (SHPs) for applications in a wide range of process-based and empirical models, thereby enabling the assessment of soil hydraulic effects on hydrological, biogeochemical, and ecological processes. At least more than 4 decade...
Research results on the formation and transport of dissolved organic carbon (DOC) in the catchment area of the Sosa reservoir. (in German)
Soil hydraulic properties (SHPs), particularly soil water retention capacity and hydraulic conductivity of unsaturated soils, are among the key properties that determine the hydrological functioning of terrestrial systems. Some large collections of SHPs, such as the UNSODA and HYPRES databases, have already existed for more than 2 decades. They hav...
Hydro-pedotransfer functions (PTFs) relate easy-to-measure and readily available soil information to soil hydraulic properties for applications in a wide range of process-based and empirical models, thereby enabling the assessment of soil hydraulic effects on hydrological, biogeochemical, and ecological processes. At least more than four decades of...
Soil hydraulic properties (SHP), particularly soil water retention capacity and hydraulic conductivity of unsaturated soils, are among the key properties that determine the hydrological functioning of terrestrial systems. Some large collections of SHP, such as the UNSODA and HYPRES databases, already exist for more than two decades. They have provi...
The famous Darcy model relates the pressure gradient and the hydraulic conductivity of a porous filter layer to the flow rate of water through the filter. This macroscale linear flow model for saturated water flow through porous media is central for a whole class of environmental and technical processes. We present the foundations, assumptions and...
The link between landscape properties and hydrological functioning is the very foundation of hydrological sciences. The fundamental perception that landscape organisation and its hydrological and biogeochemical processes co-develop is often discussed. However, different landscape characteristics and hydrological processes interact in complex ways....
The German North Sea coast is characterised by continuous dikes and below sea level elevation of a big share of the terrestrial land. The system is vulnerable to climate change and specifically to predicted increase in sea levels and extreme weather events and changes in seasonal precipitation. Therefore, adaptation measures to the predicted change...
The German North Sea coast is characterised by continuous dikes and below sea level elevation of a big share of the terrestrial land, which is drained by a complex system of canals, sluices and pumps. The area is vulnerable to climate change and specifically to increasing sea levels, changes in seasonal precipitation and increased frequency of extr...
Root water uptake (RWU), as an important process in the terrestrial water cycle, can help us to better understand the interactions in the soil–plant–atmosphere continuum. We conducted a field study monitoring soil moisture profiles in the rhizosphere of beech trees at two sites with different soil conditions. We present an algorithm to infer RWU fr...
Soil water content and matric potential are central hydrological state variables. A large variety of automated probes and sensor systems for state monitoring exist and are frequently applied. Most applications solely rely on the calibration by the manufacturers. Until now, there has been no commonly agreed-upon calibration procedure. Moreover, seve...
This dataset comprises data of an interdisciplinary pedon-scale irrigation experiment at a grassland site near Karlsruhe, Germany, including pedo-hydrological, geophysical, and remote sensing data. The objective of this experiment is to monitor soil moisture dynamics during a well-defined infiltration process with a combination of direct and non-in...
Abstract. Root water uptake (RWU) as one important process in the terrestrial water cycle can help to better understand the interactions in the soil water plant system. We conducted a field study monitoring soil moisture profiles in the rhizosphere of beech trees at two sites with different soil conditions. We infer RWU from step-shaped, diurnal ch...
Surface topography is an important source of information about the functioning and form of a hydrological landscape. Because of its key role in explaining hydrological processes and structures, and also because of its wide availability at good resolution in the form of digital elevation models (DEMs), it is frequently used to inform hydrological an...
Soil water content and matric potential are central hydrological state variables. A large variety of automated probesand sensor systems for state monitoring exists and is frequently applied. Most studies solely rely on the calibration by themanufacturers. Until now, there is no commonly agreed calibration procedure. Moreover, several opinions about...
Core Ideas
We tested a range of dual‐permeability parameterizations at plot and catchment scale.
Well‐performing parameters at plot scale did not clearly improve catchment simulation.
Vertical preferential flow was important for simulating plot‐scale observations.
At catchment scale, it appeared more important to consider fast lateral subsurface fl...
Surface topography is an important source of information about the functioning and form of a hydrological landscape. Because of its key role in explaining hydrological processes and structures, and also because of its wide availability at good resolution in the form of digital elevation models (DEM), it is frequently used to inform hydrological ana...
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...
The increasing diversity and resolution of spatially distributed data on terrestrial systems greatly enhance the potential of hydrological modeling. Optimal and parsimonious use of these data sources requires, however, that we better understand (a) which system characteristics exert primary controls on hydrological dynamics and (b) to what level of...
Non-uniform infiltration and subsurface flow in structured soils is observed in most natural settings. It arises from imperfect lateral mixing of fast advective flow in structures and diffusive flow in the soil matrix and remains one of the most challenging topics with respect to match observation and modelling of water and solutes at the plot scal...
The present study corroborates that the free energy state of soil water offers a new perspective on storage dynamics and similarity of hydrological systems that cannot be inferred from the usual comparison of soil moisture observations or groundwater levels. We show that the unsaturated zone of any hydrological system is characterized by a system-...
Core Ideas
Dynamics of earthworm activity change macropore networks temporally.
In the topsoil, macropore numbers were largest in autumn and smallest in summer.
Temporal dynamics in macropore networks affected their hydrological impact.
Modeling confirmed that temporal macropore dynamics affect infiltration patterns.
Macropores greatly affect wate...
The increasing diversity and resolution of spatially distributed data on terrestrial systems greatly enhances the potential of hydrological modeling. Optimal and parsimonious use of these data sources implies, however, that we better understand (a) which system characteristics exert primary controls on hydrological dynamics and (b) to what level of...
Non-uniform infiltration and subsurface flow in structured soils is observed in most natural settings. It arises from imperfect lateral mixing of fast advective flow in structures and diffusive flow in the soil matrix and remains one of the most challenging topics with respect to match observation and modelling of water and solutes at the plot scal...
The study deals with the identification and characterization of rapid subsurface flow structures through pedo- and geo-physical measurements and irrigation experiments at the point, plot and hillslope scale. Our investigation of flow-relevant structures and hydrological responses refers to the general interplay of form and function, respectively. T...
The phrase form and function was established in architecture and biology and refers to the idea that form and functionality are closely correlated, influence each other, and co-evolve. We suggest transferring this idea to hydrological systems to separate and analyze their two main characteristics: their form, which is equivalent to the spatial stru...
The baffling diversity of runoff generation processes, alongside our sketchy understanding of how physiographic characteristics control fundamental hydrological functions of water collection, storage, and release, continue to pose major research challenges in catchment hydrology. Here, we propose innovative data-driven diagnostic signatures for ove...
This study explores the suitability of a single hillslope as a parsimonious representation of a catchment in a physically based model. We test this hypothesis by picturing two distinctly different catchments in perceptual models and translating these pictures into parametric setups of 2-D physically based hillslope models. The model parametrization...
Within this study we propose a stochastic approach to simulate soil water dynamics in the unsaturated zone by using a non-linear, space domain random walk of water particles. Soil water is represented by particles of constant mass, which travel according to the Itô form of the Fokker–Planck equation. The model concept builds on established soil phy...
For understanding water and solute transport processes, knowledge about the respective hydraulic properties is necessary. Commonly, hydraulic parameters are estimated via pedo-transfer functions using soil texture data to avoid cost-intensive measurements of hydraulic parameters in the laboratory. Therefore, current soil texture information is only...
Despite the numerous hydrological models existing in hydrology we are limited to a few forms of conceptualization when abstracting hydrological systems into different model frameworks. Speaking in black and white terms, in most cases hydrological systems are either represented spatially lumped with conceptual models or spatially explicit with physi...
Rapid subsurface flow in structured soils facilitates fast vertical and lateral redistribution of event water. Despite their significance and omnipresence the related processes are challenging hydrological exploration, monitoring, modeling and theory. One reason for this is that flow processes at high velocities are difficult to observe in the subs...
Preferential flow is omnipresent in natural systems. It links multiple scales from single pores to entire hillslopes and potentially influences the discharge dynamics of a catchment. However, there is still a lack of appropriate monitoring techniques and thus, process understanding. In this study, a promising combination of 2D time-lapse ground-pen...
For understanding water and solute transport processes knowledge about the respective hydraulic properties is necessary. Commonly, hydraulic parameters are estimated via pedo-transfer functions using soil texture data to avoid cost intensive measurements of hydraulic parameters in the laboratory. Therefore, current soil texture information is only...
Hydrological modelling studies often start with a qualitative sketch of the hydrological processes of a catchment. These so-called perceptual models are often pictured as hillslopes and are generalizations displaying only the dominant and relevant processes of a catchment or hillslope. The problem with these models is that they are prone to become...
Within this study we propose a stochastic approach to simulate soil water dynamics in the unsaturated zone by using a non-linear, space domain random walk of water particles. Soil water is represented by particles of constant mass, which travel according to the Itô form of the Fokker Planck equation. The model concept builds on established soil phy...
The question of how catchments actually "function" has probably caused many sleepless nights as it is still an unsolved and challenging scientific question. Here, we approach this question from the similarity perspective. Instead of comparing single physiographic features of individual catchments we explore the interplay of state and structure on d...
This thesis quests after minimum adequacy of model complexity, geophysical exploration and functional unit identification through examples from the Attert experimental basin. With emphasis on a joined examination of theoretical concepts, experimental methodology and modelling approaches the study addresses landscape and process analysis, targeted e...
This opinion paper proposes a novel framework for exploring how spatial organization alongside with spatial heterogeneity controls functioning of intermediate scale catchments of organized complexity. Key idea is that spatial organization in landscapes implies that functioning of intermediate scale catchments is controlled by a hierarchy of functio...
Many experiments and studies have shown, that soil water movement
follows preferential paths - across scales, across flow domains and
across conditions. At the same time different flow domains are widely
noticed in several model abstractions (stochastic stream tubes, double
domain approaches, explicit structure definitions, and others). Both
aspect...
In the search for a unified physical representation of water, solute and
energy dynamics in structured soils, we soon lack observational data and
techniques. Simultaneously, effective parameters override the value of
the precious data we gathered. Both imply a revision of current
concepts. We present a model approach with two key elements: 1) a
Lag...
Understanding catchment structures and properties as most probable
result of past work during their evolution under the continuous
depletion of gradients opens a connection of landscape properties to
dominating processes. While a qualitative description from the expert's
perspective can comprehend most of these; a distinct objective
delineation int...
"Predictions in Ungauged Basins" are a challenging task - especially
when it comes to meso-scale rural catchments. We present a rapid data
assessment scheme based on a functional perspective on the landscape for
a hydrological land use decision support model. A hierarchical merging
of top down and bottom up approaches combines hydrology, soil physi...
The goal of this study was to assess the feasibility of using Tropical Rainfall Measuring Mission (TRMM) and Moderate Resolution Imaging Spectroradiometer (MODIS) products to drive a mesoscale hydrologic model (mHM) in a poorly gauged basin. Other remotely sensed products such as LandSat and Shuttle Radar Topography Mission (SRTM) were also used to...
This letter details the collective views of a number of independent researchers on the technical assessment and evaluation of environmental models and software. The purpose is to stimulate debate and initiate action that leads to an improved quality of model development and evaluation, so increasing the capacity for models to have positive outcomes...
The water balance equation remained the single most basis of all hydrological models during the last decades. While we strive to find ways to integrate the whole human-hydro-geo-eco-system into the water balance, energy as driver for the processes we hope to capture is often forgotten. In order to advance hydrological models catchments as self-orga...
Application of spatial TDR-inversion technique during a field experiment in a complex mid mountainous area Graeff, T., Schlaeger, S., Bauer, A., Morgner, M., Jakisch, C., Bronstert, A., Zehe, E. Transient soil moisture profiles yield valuable information of near surface processes. A recently developed reconstruction algorithm based on the telegraph...
Vegetation plays a major role both in the atmospheric and terrestrial water cycle. Cropland covers a large proportion of the global terrestrial area (i.e. 38% globally in 2005, FAOSTAT). Accordingly, crop models have become increasingly prominent for studying the impact of Global Change both on economic welfare and on the influence of vegetation on...
Vegetation plays a major role both in the atmospheric and terrestrial water cycle. A great deal of vegetation cover in the developed world consists of agricultural used land (i.e. 44 % of the territory of the EU). Therefore, crop models have become increasingly prominent for studying the impact of Global Change both on economic welfare as well as o...
The development of rural areas concerning food security, sustainability and social-economic stability is key issue to the globalized community. Regarding the current state of climatic change, especially semi-arid regions influenced by monsoon or El Niño are prone to extreme weather events. Droughts, flooding, erosion, degradation of soils and water...
Questions
Question (1)
Soil systems comprise a multitude of processes across scales and disciplines. As they are part of the "critical zone" the exploration and monitoring of these systems is central in most terrestrial environmental studies.
However, the thorough investigation of soil systems rarely succeeds in jointly approaching the pedological, biogeochemical, ecological and hydrological aspects. Despite great progress in the theory of sampling design and monitoring strategies, the practical exploration of these systems often requires adaptations and compromises. Furthermore, knowledge about sampling strategies and subsequent analysis techniques is frequently not considered when setting up a monitoring scheme or model, bearing large potential for inefficient designs, errors or circular reasoning.
This session invites practitioners as well as theoreticians to present insights from investigations of soils as complex systems with a focus on sampling and monitoring strategies, potential mismatch of process perception and observations, sampling design failures and innovations, conceptual obstacles to transdisciplinary exploration, methods to find light in the darkness of heterogeneity, and novel monitoring approaches. We seek to bring together various findings on exploring soil systems in order to continue the discussion about adequate methods towards a common methodological strategy and standard.
We are looking forward to your abstracts sharing your insights and contributing to a vivid discussion. We especially solicit work of young scientists and challenges also established scientists are troubled with.
Please note the EGU abstract deadline Jan 11, 2017, 13:00 CET or Dec 1, 2016 if you intend to apply for financial support.
