Matthias Munz

Universität Potsdam · Institute of Environmental Science and Geography

River bank filtration (RBF) is considered to efficiently remove nitrate and trace organic micropollutants (OMP) from polluted surface waters. This is essential for maintaining good groundwater quality and providing high quality drinking water. Predicting the fate of OMP during RBF is difficult as the biogeochemical factors controlling the removal e...

Bank filtration is considered to improve water quality through microbially mediated degradation of pollutants and is suitable for waterworks to increase their production. In particular, aquifer temperatures and oxygen supply have a great impact on many microbial processes. To investigate the temporal and spatial behavior of selected organic micropo...

Riverbed sediments have recently been found to be an important reservoir for microplastics. But the hydrogeological factors that control the abundance of microplastics are complex and conceptual frameworks priorising the parameters affecting their transport and retention during deep riverbed filtration are still missing. In this study a series of s...

Riverbed sediments have been identified as temporary and long-term accumulation sites for microplastic particles (MPs), but the relocation and retention mechanisms in riverbeds still need to be better understood. In this study, we investigated the depth-specific occurrence and distribution (abundance, type, and size) of MPs in river sediments down...

Flow patterns in conjunction with seasonal and diurnal temperature variations control ecological and biogeochemical conditions in hyporheic sediments. In particular, hyporheic temperatures have a great impact on many temperature-sensitive microbial processes. In this study, we used 3-D coupled water flow and heat transport simulations applying the...

A permeable reactive barrier (PRB) can be deployed to remediate acid mine drainage. The performance of a PRB material under different boundary conditions (pH, flow velocity, and sulfate concentration) was investigated in a series of column experiments applying in‐situ optical sensing methods for pH and oxygen detection. The reactive material consis...

Microplastic particles (MPP) occur in various environmental compartments all over the world. They have been frequently investigated in oceans, freshwaters, and sediments, but studying their distribution in space and time is somewhat limited by the time-consuming nature of the available accurate detection strategies. Here, we present an enhanced app...

Zusammenfassung Küstennahe Niedermoore wurden durch den Menschen verändert, bspw. durch das Anlegen von Entwässerungsgräben, dem Bau von Küstenschutzdeichen oder aktuell einer Renaturierung. Außerdem ist es wichtig die komplexe Interaktion mit der See zu verstehen, um Aussagen über die zukünftige Entwicklung treffen zu können. In der vorliegenden S...

The original version of this article unfortunately contained mistakes.

Bank filtration (BF) is an established indirect water-treatment technology. The quality of water gained via BF depends on the subsurface capture zone, the mixing ratio (river water versus ambient groundwater), spatial and temporal distribution of subsurface travel times, and subsurface temperature patterns. Surface-water infiltration into the adjac...

The affiliation of Daniel Strasser is hereby corrected to: Department of Geotechnical Engineering, Federal Waterways Engineering and Research Institute (BAW), Kussmaulstraße 17, 76187 Karlsruhe, Germany

The functioning of the surface water-groundwater interface as buffer, filter and reactive zone is important for water quality, ecological health and resilience of streams and riparian ecosystems. Solute and heat exchange across this interface is driven by the advection of water. Characterizing the flow conditions in the streambed is challenging as...

The application of heat as a hydrological tracer has become a standard method for quantifying water fluxes between groundwater and surface water. Typically, time series of temperatures in the surface water and in the sediment are observed and are subsequently evaluated by a vertical 1D representation of heat transport by advection and dispersion. S...

Flow pattern and seasonal as well as diurnal temperature variations control ecological and biogeochemical condi-tions in hyporheic sediments. In particular, hyporheic temperatures have a great impact on many microbial pro-cesses. In this study we used 3-D coupled water flow and heat transport simulations applying the HydroGeoSpherecode in combinati...

The application of heat as a hydrological tracer has become a standard method for quantifying water fluxes between groundwater and surface water. The typical application is to estimate vertical water fluxes in the shallow subsurface beneath streams or lakes. For this purpose, time series of temperatures in the surface water and in the sediment are...

The functioning of the surface water-groundwater interface as buffer, filter and reactive zone is important for water quality, ecological health and resilience of streams and riparian ecosystems. Solute and heat exchange across this interface is driven by the advection of water. Characterizing the flow conditions in the streambed is challenging as...

The analytical evaluation of diurnal temperature variation in riverbed sediments provides detailed information on exchange fluxes between rivers and groundwater. The underlying assumption of the stationary, one-dimensional vertical flow field is frequently violated in natural systems where subsurface water flow often has a significant horizontal co...

In this study we used the deterministic, fully-integrated surface-subsurface flow and heat transport model (HydroGeoSphere) to investigate the spatial and temporal variability of surface water-groundwater (SFW-GW) interaction along a lowland river reach. The model incorporates the hydrological as well as the heat transport processes including (1) r...

Exchange fluxes across aquifer-river interfaces can have a major impact on the biogeochemical cycling in streambed environments. This paper presents integrated experimental and model-based investigations of physical drivers and chemical controls on streambed biogeochemcial cycling at two UK lowland rivers. It combines in-stream geophysical surveys,...

Biogeochemical turnover in hyporheic zones is known to have the potential to affect the chemical signature of surface water cycling through shallow streambed sediments. This study investigates the impact of streambed physical properties on the fate of nitrate and dissolved oxygen in groundwater upwelling through the streambed of a lowland river. Fo...

The mixing of groundwater (GW) and surface water (SW) can have substantial impact on the transformation of solutes transported between aquifer and river. The assessment of biogeochemical cycling at reactivity hotspots as the aquifer-river interface and its implications for GW and SW quality require detailed understanding of the complex patterns of...

Surface waters and groundwater are the interconnected hydrological main parts of stream catchments. They are coupled by variable water, solute and heat exchange processes through streambed sediments. The spatial and temporal variability of these exchange processes depend on the heterogeneity of hydraulic and thermal streambed properties and the int...

Concentrations of nutrients and contaminants in up-welling groundwater can significantly change along the passage through highly heterogeneous streambed sediments with substantial implications for the quality of connected surface water bodies. This study presents investigations into the physical drivers and chemical controls of nutrient transport a...

Concentrations of nutrients and contaminants in up-welling groundwater can significantly change along the passage through highly heterogeneous streambed sediments with substantial implications for the quality of connected surface water bodies. This study presents investigations into the physical drivers and chemical controls of nutrient transport a...

Quantification of subsurface water fluxes based on the one dimensional solution to the heat transport equation depends on the accuracy of measured subsurface tem-peratures. The influence of temperature probe setup on the accuracy of vertical water flux calculation was systematically evaluated in this experimental study. Four temper-5 ature probe se...

This study investigates spatial patterns and temporal dynamics of aquifer–river exchange flow at a reach of the River Leith, UK. Observations of sub-channel vertical hydraulic gradients at the field site indicate the dominance of groundwater up-welling into the river and the absence of groundwater recharge from surface water. However, observed hydr...

Quantification of subsurface water fluxes based on the one dimensional solution to the heat transport equation depends on the accuracy of measured subsurface temperatures. The influence of temperature probe setup on the accuracy of vertical water flux calculation was systematically evaluated in this experimental study. Four temperature probe setups...

Research on natural attenuation of pollutants and contaminants in the hyporheic zone HZ) has been dominated by investigations of transient storage of surface water infiltrating into and later exfiltrating from the streambed. Although volume and residence times of up-welling groundwater in the streambed are usually exceeding the cycling of surface w...

The `hyporheic zone' or `interstitial' characterises an area of intensive groundwater and surface water mixing within streambed sediments. Its physical conditions, as for instance the hydraulic conductivity and residence time, control fluxes and exchange rates between groundwater and surface water. Because of its often steep and dynamic redox gradi...

The analysis, assessment and prediction of hydrological processes and ecological conditions in an integrated river basin management require catchment scale model simulations of the water balance as well as of transport and transformation of nutrients and pollutants. Applications of coupled groundwater - surface water models for lowland catchments h...

The Hyporheic Zone (HZ) represents the spatially and temporally variable part of the streambed that is affected by the mixture of groundwater and surface water and often characterised by strong redox gradients and high turnover rates of redox reactive substances. The HZ has often been understood as a complex bioreactor with a high potential to affe...

The implications of streambed physical and chemical conditions on the hyporheic exchange between groundwater and surface water as well as on the transport and transformation of redox sensitive nutrients have been investigated for two contrasting UK upland and lowland rivers. The presented research comprises experimental investigations on nested pie...

Exchange fluxes and redox processes at the river - aquifer interface can be subject to intensive spatial and temporal variability. This paper presents an approach to use the numerical groundwater model MODFLOW to simulate river aquifer exchange for a stream section of the river Leith, UK. For the parameterisation of the river-aquifer interface of t...