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Article: A chemical and microbial characterization of selected mud volcanoes in Trinidad reveals pathogens introduced by surface water and rain water

Schulze-Makuch, Dirk / Haque, Shirin / Schmitt-Kopplin, Philippe / Stumpp, Christine / Wagner, Dirk

The science of the total environment, 707:136087

2019

Abstract: Terrestrial mud volcanoes are unique structures driven by tectonic pressure and fluids from the deep subsurface. These structures are mainly found in active tectonic zones, such as the area near the Los Bajos Fault in Trinidad. Here we report a chemical ... ...

Institution	Leibniz-Institut für Gewässerökologie und Binnenfischerei
Abstract	Terrestrial mud volcanoes are unique structures driven by tectonic pressure and fluids from the deep subsurface. These structures are mainly found in active tectonic zones, such as the area near the Los Bajos Fault in Trinidad. Here we report a chemical and microbiological characterization of three mud volcanoes, which included analyses of multiple liquid and solid samples from the mud volcanoes. Our study confirms previous suggestions that at least some of the mud volcano fluids are a mixture of deeper salt-rich water and surficial/precipitation water. No apparent water quality differences were found between sampling sites north and south of a major geological fault line. Microbiological analyses revealed diverse communities, both aerobic and anaerobic, including sulfate reducers, methanogens, carbon dioxide fixing and denitrifying bacteria. Several identified species were halophilic and likely derived from the deeper salt-rich subsurface water, while we also cultivated pathogenic species from the Vibrionaceae, Enterobacteriaceae, Shewanellaceae, and Clostridiaceae. These microorganisms were likely introduced into the mud volcano fluids both from surface water or shallow ground-water, and perhaps to a more minor degree by rain water. The identified pathogens are a major health concern that needs to be addressed.
Keywords	Contamination ; Fluids ; Isotope ; Metabolomics ; Mud volcanoes ; Pathogens
Language	English
Document type	Article
Database	Repository for Life Sciences

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Article ; Online: An in-depth analysis of Markov-Chain Monte Carlo ensemble samplers for inverse vadose zone modeling

Brunetti, Giuseppe / Šimůnek, Jiří / Wöhling, Thomas / Stumpp, Christine

Journal of Hydrology. 2023 Sept., v. 624 p.129822-

2023

Abstract: This study elucidates the behavior of Markov-Chains Monte Carlo ensemble samplers for vadose zone inverse modeling by performing an in-depth comparison of four algorithms that use Affine-Invariant (AI) moves or Differential Evolution (DE) strategies to ... ...

Abstract	This study elucidates the behavior of Markov-Chains Monte Carlo ensemble samplers for vadose zone inverse modeling by performing an in-depth comparison of four algorithms that use Affine-Invariant (AI) moves or Differential Evolution (DE) strategies to approximate the target density. Two Rosenbrock toy distributions, and one synthetic and one actual case study focusing on the inverse estimation of soil hydraulic parameters using HYDRUS-1D, are used to compare samplers in different dimensions d. The analysis reveals that an ensemble with N=d+1 chains evolved using DE-based strategies converges to the wrong stationary posterior, while AI does not suffer from this issue but exhibits delayed convergence. DE-based samplers regain their ergodic properties when using N≥2d chains. Increasing the number of chains above this threshold has only minor effects on the samplers’ performance, while initializing the ensemble in a high-likelihood region facilitates its convergence. AI strategies exhibit shorter autocorrelation times in the 7d synthetic vadose zone scenario, while DE-based samplers outperform them when the number of soil parameters increases to 16 in the actual scenario. All evaluation metrics degrade as d increases, thus suggesting that sampling strategies based only on interpolation between chains tend to become inefficient when the bulk of the posterior lays in increasingly small portions of the parameters’ space.
Keywords	Markov chain ; autocorrelation ; case studies ; soil ; vadose zone ; Markov-chain Monte Carlo ; Ensemble samplers ; Differential evolution ; Affine invariant
Language	English
Dates of publication	2023-09
Publishing place	Elsevier B.V.
Document type	Article ; Online
ZDB-ID	1473173-3
ISSN	1879-2707 ; 0022-1694
ISSN (online)	1879-2707
ISSN	0022-1694
DOI	10.1016/j.jhydrol.2023.129822
Database	NAL-Catalogue (AGRICOLA)

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Article ; Online: Experimental and simulated microplastics transport in saturated natural sediments: Impact of grain size and particle size.

Li, Wang / Brunetti, Giuseppe / Zafiu, Christian / Kunaschk, Marco / Debreczeby, Monika / Stumpp, Christine

Journal of hazardous materials

2024 Volume 468, Page(s) 133772

Abstract: Microplastics (MPs) present in terrestrial environments show potential leaching risk to deeper soil layers and aquifer systems, which threaten soil health and drinking water supply. However, little is known about the environmental fate of MPs in natural ... ...

Abstract	Microplastics (MPs) present in terrestrial environments show potential leaching risk to deeper soil layers and aquifer systems, which threaten soil health and drinking water supply. However, little is known about the environmental fate of MPs in natural sediments. To examine the MPs transport mechanisms in natural sediments, column experiments were conducted using different natural sediments and MPs (10-150 µm) with conservative tracer. Particle breakthrough curves (BTCs) and retention profiles (RPs) were numerically interpreted in HYDRUS-1D using three different models to identify the most plausible deposition mechanism of MPs. Results show that the retention efficiency for a given particle size increased with decreasing grain size, and RPs exacerbated their hyper-exponential shape in finer sediments. Furthermore, the amounts of MPs present in the effluent increased to over 85 % as MPs size decreased to 10-20 µm in both gravel and coarse sand columns, while all larger MPs (125-150 µm) were retained in the coarse sand column. The modeling results suggested that the blocking mechanism becomes more important with increasing particle sizes. In particular, the attachment-detachment without blocking was the most suited parameterization to interpret the movement of small MPs, while a depth-dependent blocking approach was necessary to adequately describe the fate of larger particles.
Language	English
Publishing date	2024-02-10
Publishing country	Netherlands
Document type	Journal Article
ZDB-ID	1491302-1
ISSN	1873-3336 ; 0304-3894
ISSN (online)	1873-3336
ISSN	0304-3894
DOI	10.1016/j.jhazmat.2024.133772
Database	MEDical Literature Analysis and Retrieval System OnLINE

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Article: Partitioning evapotranspiration using water stable isotopes and information from lysimeter experiments

Liebhard, Gunther / Klik, Andreas / Stumpp, Christine / Nolz, Reinhard

Hydrological sciences journal. 2022 Mar. 12, v. 67, no. 4

2022

Abstract: Stable isotope techniques can be used to investigate evapotranspiration and its partitioning into evaporation and transpiration. However, verification is often difficult due to missing information about actual evapotranspiration. Therefore, in this study ...

Abstract	Stable isotope techniques can be used to investigate evapotranspiration and its partitioning into evaporation and transpiration. However, verification is often difficult due to missing information about actual evapotranspiration. Therefore, in this study a methodology tested for laboratory conditions was modified for field applications. Evapotranspiration, which was determined by weighing lysimeters, and isotope techniques were combined with soil water and lysimeter measurements to calculate evaporation and transpiration rates of soybean under natural conditions. The case study was conducted in 2019 in Groß-Enzersdorf, Austria. The results show that the methodology was suited to measure actual variations of evaporation and transpiration ratios, even during dry periods. Weekly evaporation (0.5–2.2 mm d⁻¹) and transpiration (1.3–4.3 mm d⁻¹) rates as well as the respective ratios (transpiration 43–85%) agreed with the results of numerical modelling and values from the literature, confirming the applicability of the modified methodology for portioning evapotranspiration in the field.
Keywords	case studies ; evaporation ; evapotranspiration ; lysimeters ; soil water ; soybeans ; stable isotopes ; transpiration ; Austria
Language	English
Dates of publication	2022-0312
Size	p. 646-661.
Publishing place	Taylor & Francis
Document type	Article
ISSN	2150-3435
DOI	10.1080/02626667.2022.2030866
Database	NAL-Catalogue (AGRICOLA)

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Article: Balancing exploitation and exploration: A novel hybrid global-local optimization strategy for hydrological model calibration

Brunetti, Giuseppe / Stumpp, Christine / Šimůnek, Jiří

Environmental modelling & software. 2022 Apr., v. 150

2022

Abstract: Optimization problems in hydrological modeling are frequently solved using local or global search strategies, which either maximize exploitation or exploration. Thus, the elevated performance of one strategy for one class of problems is often offset by ... ...

Abstract	Optimization problems in hydrological modeling are frequently solved using local or global search strategies, which either maximize exploitation or exploration. Thus, the elevated performance of one strategy for one class of problems is often offset by poor performance for another class. To overcome this issue, we propose a hybrid strategy, G-CLPSO, that combines the global search characteristics of the Comprehensive Learning Particle Swarm Optimization (CLPSO) with the exploitation capability of the Marquardt-Levenberg (ML) method and implement it into the hydrological model, HYDRUS. Benchmarks involving optimizing non-separable unimodal and multimodal functions demonstrate that G-CLPSO outperforms CLPSO in terms of accuracy and convergence. Synthetic modeling scenarios involving the inverse estimation of soil hydraulic properties are used to compare the G-CLPSO against the original HYDRUS ML solver, the gradient-based algorithm PEST, and the stochastic SCE-UA strategy. Results demonstrate the superior performance of the G-CLPSO, suggesting a potential use in other environmental problems.
Keywords	algorithms ; computer software ; hydrologic models
Language	English
Dates of publication	2022-04
Publishing place	Elsevier Ltd
Document type	Article
ISSN	1364-8152
DOI	10.1016/j.envsoft.2022.105341
Database	NAL-Catalogue (AGRICOLA)

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Article ; Online: Stable isotope patterns of German rivers with aspects on scales, continuity and network status

Koeniger, Paul / Stumpp, Christine / Schmidt, Axel

Isotopes in Environmental and Health Studies. 2022 Nov. 02, v. 58, no. 4-6 p.363-379

2022

Abstract: In Germany, river monitoring for tritium started in the early 1970s. Today this monitoring network consists of 50 stations and includes stable isotopes. The stable isotope time series to the end of 2021 are at least four years and for some stations up to ...

Abstract	In Germany, river monitoring for tritium started in the early 1970s. Today this monitoring network consists of 50 stations and includes stable isotopes. The stable isotope time series to the end of 2021 are at least four years and for some stations up to 30 years long. Daily river water samples were collected during an extraordinary dry season from October 2018 until end of January 2019 from six selected stations of the Rhine and five stations of the Elbe basin. The most dominating stable isotope effects in river water are the seasonal and altitude effects, but also a continental effect is visible. The isotopes indicate snow and ice melt contributions in the Rhine and Danube during the summer months and a consecutive dilution of these signals by mixing with tributary rivers. Close to the coasts in northern Germany, stable isotope patterns reflect influence of seawater and tides. Daily patterns during the dry season 2018/2019 surprisingly do not exhibit extreme changes but rather trends of enhanced groundwater contribution. Long-term continual data across scales are important for comparing and identifying hydrological processes in German river basins of different size and mean catchment altitudes, and highlight the benefits of a co-organized national network.
Keywords	altitude ; basins ; dry season ; groundwater ; ice ; river water ; rivers ; seawater ; snow ; stable isotopes ; summer ; time series analysis ; tritium ; watersheds ; Germany ; deuterium ; oxygen-18 ; German Rivers ; Rhine ; Weser ; Elbe ; Danube
Language	English
Dates of publication	2022-1102
Size	p. 363-379.
Publishing place	Taylor & Francis
Document type	Article ; Online
ZDB-ID	2100190-X
ISSN	1477-2639 ; 0021-1915 ; 1025-6016
ISSN (online)	1477-2639
ISSN	0021-1915 ; 1025-6016
DOI	10.1080/10256016.2022.2127702
Database	NAL-Catalogue (AGRICOLA)

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Article ; Online: A Bayesian perspective on the information content of soil water measurements for the hydrological characterization of the vadose zone

Schübl, Marleen / Stumpp, Christine / Brunetti, Giuseppe

Journal of Hydrology. 2022 Oct., v. 613 p.128429-

2022

Abstract: Transient measurements from soil water monitoring installments are frequently coupled with Richards-based solvers to inversely estimate soil hydraulic parameters (SHPs) and numerically describe vadose zone water fluxes, such as groundwater recharge. To ... ...

Abstract	Transient measurements from soil water monitoring installments are frequently coupled with Richards-based solvers to inversely estimate soil hydraulic parameters (SHPs) and numerically describe vadose zone water fluxes, such as groundwater recharge. To reduce model predictive uncertainty, the experimental setup should be designed to maximize the information content of observations. However, in practice, this is generally done by relying on the a priori expertise of the scientist/user, without exploiting the advantages of model-based experimental design. Thus, the main aim of this study is to demonstrate how model-based experimental design can be used to maximize the information content of observations in multiple synthetic scenarios encompassing different soil textural compositions and climatic conditions. The hydrological model HYDRUS is coupled with a Nested Sampling estimator to calculate the parameters' posterior distributions and the Kullback-Leibler divergences. Results indicate that the combination of seepage flow, soil water content, and soil matric potential measurements generally leads to highly informative designs especially for fine textured soils, while results from coarse soils are generally affected by higher uncertainty. Additionally, the propagation of parameter uncertainties in a contrasting (dry) climate scenario strongly increased prediction uncertainties for sandy soil, not only in terms of the cumulative amount and magnitude of the peak, but also in the temporal variability of the seepage flow. A complementary real-world application with a sandy soil lysimeter identified a combination of seepage data and matric potential as the most informative design and confirmed findings of the synthetic scenarios, in which matric potential proved to be more informative than soil water content measurements.
Keywords	Bayesian theory ; climate ; experimental design ; groundwater recharge ; hydrologic models ; lysimeters ; prediction ; sandy soils ; scientists ; seepage ; soil matric potential ; soil water ; soil water content ; temporal variation ; uncertainty ; vadose zone ; Lysimeter ; Water flow modeling ; HYDRUS ; Nested Sampling ; Bayesian data analysis
Language	English
Dates of publication	2022-10
Publishing place	Elsevier B.V.
Document type	Article ; Online
Note	Use and reproduction
ZDB-ID	1473173-3
ISSN	1879-2707 ; 0022-1694
ISSN (online)	1879-2707
ISSN	0022-1694
DOI	10.1016/j.jhydrol.2022.128429
Database	NAL-Catalogue (AGRICOLA)

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Article: Sensitivity analysis of soil infiltration processes

Brunetti, Giuseppe / Schübl, Marleen / Santner, Katharina / Stumpp, Christine

Österreichische Wasser- und Abfallwirtschaft. 2022 Apr., v. 74, no. 3-4

2022

Abstract: Infiltration processes play a key role in the generation of pluvial floods. Whether surface flow is generated depends, among other things, on soil hydraulic properties. Future improved protection against pluvial floods is thus based on an improved ... ...

Title translation	Sensitivitätsanalyse zu Infiltrationsprozessen in Böden
Abstract	Infiltration processes play a key role in the generation of pluvial floods. Whether surface flow is generated depends, among other things, on soil hydraulic properties. Future improved protection against pluvial floods is thus based on an improved process understanding of infiltration processes in soils in order to identify conditions that lead to pluvial floods and parameter that are crucial for the prediction of events. Therefore, the KINEROS model was used for a global and local sensitivity analysis to identify parameters that most influence overland flow and to calculate overland flow as a function of initial soil saturation level for different rainfall amounts at 14 locations in Austria. The global sensitivity analysis showed that especially the factors saturated hydraulic conductivity and surface roughness significantly influence both the total runoff volume and its peak. The distribution and intensity of precipitation also have a major influence on the runoff process. In contrast, slope and initial soil saturation have a moderate impact on runoff peak and volume, respectively. Even though the degree of saturation was less crucial, the local sensitivity analysis shows a nonlinear relationship between the initial degree of soil saturation and the total runoff volume especially for the soils with medium and high saturated hydraulic conductivity. It was clearly demonstrated that hydrologic models combined with detailed statistical analysis are an important tool for analyzing and evaluating hydrologic processes and their uncertainties at the plot scale.
Keywords	overland flow ; prediction ; rain ; runoff ; saturated hydraulic conductivity ; statistical analysis ; surface roughness ; Austria
Language	German
Dates of publication	2022-04
Size	p. 179-186.
Publishing place	Springer Vienna
Document type	Article
ZDB-ID	1186984-7
ISSN	1613-7566 ; 0945-358X
ISSN (online)	1613-7566
ISSN	0945-358X
DOI	10.1007/s00506-022-00839-8
Database	NAL-Catalogue (AGRICOLA)

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Article ; Online: Stable isotope patterns of German rivers with aspects on scales, continuity and network status.

Koeniger, Paul / Stumpp, Christine / Schmidt, Axel

Isotopes in environmental and health studies

2022 Volume 58, Issue 4-6, Page(s) 363–379

Abstract	In Germany, river monitoring for tritium started in the early 1970s. Today this monitoring network consists of 50 stations and includes stable isotopes. The stable isotope time series to the end of 2021 are at least four years and for some stations up to 30 years long. Daily river water samples were collected during an extraordinary dry season from October 2018 until end of January 2019 from six selected stations of the Rhine and five stations of the Elbe basin. The most dominating stable isotope effects in river water are the seasonal and altitude effects, but also a continental effect is visible. The isotopes indicate snow and ice melt contributions in the Rhine and Danube during the summer months and a consecutive dilution of these signals by mixing with tributary rivers. Close to the coasts in northern Germany, stable isotope patterns reflect influence of seawater and tides. Daily patterns during the dry season 2018/2019 surprisingly do not exhibit extreme changes but rather trends of enhanced groundwater contribution. Long-term continual data across scales are important for comparing and identifying hydrological processes in German river basins of different size and mean catchment altitudes, and highlight the benefits of a co-organized national network.
MeSH term(s)	Hydrology ; Germany ; Isotopes ; Water
Chemical Substances	Isotopes ; Water (059QF0KO0R)
Language	English
Publishing date	2022-10-11
Publishing country	England
Document type	Journal Article
ZDB-ID	2100190-X
ISSN	1477-2639 ; 0021-1915 ; 1025-6016
ISSN (online)	1477-2639
ISSN	0021-1915 ; 1025-6016
DOI	10.1080/10256016.2022.2127702
Database	MEDical Literature Analysis and Retrieval System OnLINE

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Article ; Online: Balancing precision and throughput of δ17O and Δ'17O analysis of natural waters by Cavity Ringdown Spectroscopy

Terzer-Wassmuth, Stefan / Wassenaar, Leonard I. / Araguás-Araguás, Luis J. / Stumpp, Christine

MethodsX. 2023, v. 10 p.102150-

2023

Abstract: δ¹⁷O and Δ'¹⁷O are emerging tracers increasingly used in isotope hydrology, climatology, and biochemistry. Differentiating small relative abundance changes in the rare ¹⁷O isotope from the strong covariance with ¹⁸O imposes ultra-high precision ... ...

Abstract	δ¹⁷O and Δ'¹⁷O are emerging tracers increasingly used in isotope hydrology, climatology, and biochemistry. Differentiating small relative abundance changes in the rare ¹⁷O isotope from the strong covariance with ¹⁸O imposes ultra-high precision requirements for this isotope analysis. Measurements of δ¹⁷O by Cavity Ringdown Spectroscopy (CRDS) are attractive due to the ease of sample preparation, automated throughput, and avoidance of chemical conversions needed for isotope-ratio mass spectrometry. However, the CRDS approach requires trade-offs in measurement precision and uncertainty. In this protocol document, we present the following:•New analytical procedures and a software tool for conducting δ¹⁷O and Δ'¹⁷O measurements by CRDS.•Outline a robust uncertainty framework for Δ'¹⁷O determinations.•Description of a CRDS performance framework for optimizing throughput, instrumental stability, and Δ'¹⁷O measurement precision and accuracy.
Keywords	biochemistry ; climatology ; computer software ; covariance ; hydrology ; isotopes ; mass spectrometry ; uncertainty ; 17O ; Triple-oxygen isotopes ; CRDS ; Stable isotopes ; Isotope hydrology ; Water ; Analyses ; Error propagation ; Balancing precision and throughput of δ17O and Δ'17O analysis of natural waters by Cavity Ringdown Spectroscopy
Language	English
Publishing place	Elsevier B.V.
Document type	Article ; Online
Note	Use and reproduction
ZDB-ID	2830212-6
ISSN	2215-0161
ISSN	2215-0161
DOI	10.1016/j.mex.2023.102150
Database	NAL-Catalogue (AGRICOLA)

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