Research interests

• Simulation of pesticide entries into surface waters
• Risk assessment of pesticide entries and effects to aquatic communities
• GIS-applications for environmental tasks
• Planning and implementation of database applications
• Software development with focus on surface waters and EU water framework directive

Publications

Probst, M., Berenzen, N., Lentzen-Godding, A., Schulz, R. 2005. Scenario based simulation of runoff-related pesticide entries into small streams on a landscape level. Ecotoxicology and Environmental Safety 62/2 (2005) 145-159. (→ abstract)

Probst, M., Berenzen, N., Lentzen-Godding, A., Schulz, R., Liess, M. 2004. Linking land use variables and invertebrate taxon richness in small and medium-sized agricultural streams on a landscape level. Ecotoxicology and Environmental Safety 60/2 (2005) 140-146. (→ abstract)

Contributions to conferences, workshops and proceedings:

Probst, M. 2007. Simulation und Beurteilung der Pflanzenschutzmittelbelastung kleiner Fließgewässer auf Landschaftsebene. Talk on the ESRI group meeting (region southwest) on April 20th 2007, at the MEGARON Mannheim hosted by Dr. Knoell Consult GmbH Mannheim.

Probst, M., Berenzen, N., Lentzen-Godding, A. 2002. Informationssystem zur öko-toxikologischen Bewertung der Gewässergüte in Bezug auf Pflanzenschutzmitteleinträge aus der Landwirtschaft - Systemaufbau und Anwendungsmöglichkeiten. Deutsche Gesellschaft für Limnologie (DGL), Tagungsbericht 2002, Braunschweig, Germany, Band 2, 585-589.

Probst, M. 2002. Praktische Umsetzung der EU-WRRL in Niedersachsen: Erfassung und Bewertung - Die Gewässerinformationssysteme BOG-2000 und BOG-Archiv. Deutsche Gesellschaft für Limnologie (DGL), Tagungsbericht 2002, Braunschweig, Germany, Band 1, 180-184.

Reports

Schulz, R., Liess, M., Berenzen, N., Lentzen-Godding, A., Probst, M. 2003. Abschlußbericht zum Forschungsvorhaben des Bundesministeriums für Bildung und Forschung, Förderkennzeichen 0339804, "Informationssystem zur ökotoxikologischen Bewertung der Gewässergüte in Bezug auf Pflanzenschutzmitteleinträge aus der Landwirtschaft“. Download link → http://edok01.tib.uni-hannover.de/edoks/e01fb04/381683206.pdf (TIB: Technical library, University Hannover).

Software projects

Probst, M. 2007. Online Risk Pesticide Simulator: Java applet for the simulation and risk prediction of in-stream concentrations of pesticides. Version 1.0. © 2007 Dr. Michael Probst, → Software-Development & Consulting Probst, Braunschweig, Germany . Internet-Link: → http://www.mipro-online.de/science/psmsim/index.html.

Probst, M., Berenzen, N., Lentzen-Godding, A. 2003. PSM-SIM: Ein Informationssystem zur ökotoxikologischen Bewertung der Gewässergüte in Bezug auf Pflanzenschutzmitteleinträge aus der Landwirtschaft, Version 1.2.1 / 27.11.2003. Anwendungsprogramm für MS-Windows®, © TU-Braunschweig, AG-Limnologie.

PhD thesis

Probst, M. 2005. "Simulation and assessment of pesticide entries into small
streams on a landscape level". Dissertation, Department 7: Environmental sciences at the University Koblenz-Landau, Campus Landau. 139 p. (→ summary). Download link → http://kola.opus.hbz-nrw.de/frontdoor.php?source_opus=24 (Library of the University Koblenz-Landau).

Diploma thesis

Probst, M. 1998. "Entwurf, Implementierung und Anwendung eines Informationssystems zur Untersuchung der Reaktion aquatischer Lebensgemeinschaften auf diffuse Insektizideinträge". Diplomarbeit, Technische Universität Braunschweig:119 p.

Probst, M., Berenzen, N., Lentzen-Godding, A., Schulz, R. 2005. Scenario based simulation of runoff-related pesticide entries into small streams on a landscape level. Ecotoxicology and Environmental Safety 62/2 (2005) 145-159.

The prediction of runoff-related pesticide entry into surface waters on a landscape level usually requires considerable efforts regarding input data, time and personnel. Therefore the need for an easy to use simulation tool with easily accessible input data, for example from already existing public sources, is obvious. In this paper we present a simulation tool for the simulation of pesticide entry from arable land into adjacent streams. Our aim was to develop a tool applicable on the landscape-level using “real world data” from numerous sites as well as for the simulation of parameter case studies concerning particular parameters at single sites. We used the REXTOX (Ratio of EXposure to TOXicity) model proposed by the OECD, which had been successfully validated in the study area as part of a previous study, and which was extended to calculate pesticide concentrations in adjacent streams. We simulated the pesticide entry on the landscape level at 737 sites in small streams situated in the central lowland of Germany with winter wheat, barley and sugar beat as the main agricultural crops. A sensitivity analysis indicated that the most significant model parameters were the width of the no-application-zone and the degree of plant-interception. The simulation was carried out for the 15 most frequently detected found substances in the study area using eight different environmental scenarios, covering variation of the width of the no-application-zone, climate and seasonal scenarios. The highest in-stream concentrations were predicted at a scenario using no (0 m) buffer zone in conjunction with increased precipitation. According to the predicted concentrations, the risk for the aquatic communities was estimated based on standard toxicity tests and the application of a safety factor. The simulation results are presented by means of risk maps for the study area showing the simulated pesticide concentration and the resulting ecological risk for numerous sites under varying scenarios as well as by case study diagrams with focus on the model behavior under the influence of single parameters. Risk maps confirmed the importance of no-application (buffer) zones for the levels of pesticide input. They also indicated the importance of the existing no-application zones for certain compounds - and in some cases the need for a further evaluation of these regulations. The simulation tool was implemented as a standard PC-software combining the REXTOX-model with a geographical information system (GIS) and can be used on any current personal computer. All input data was taken from public sources of German authorities. With little effort the tool should be applicable for other areas with similar data quality.

Keywords: risk assessment, pesticides, runoff, buffer zones, simulation, modeling, landscape level, climate change, risk mitigation

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Probst, M., Berenzen, N., Lentzen-Godding, A., Schulz, R., Liess, M. 2004. Linking land use variables and invertebrate taxon richness in small and medium-sized agricultural streams on a landscape level. Ecotoxicology and Environmental Safety 60/2 (2005) 140-146.

In this study the average numbers of invertebrate species across an arable landscape in central Germany (surveys from 15 years in 90 streams at 202 sites) were assessed for their correlation with environmental factors such as stream width, land use (arable land, forest, pasture, settlement), soil type and agricultural derived stressors. The stress originating from arable land was estimated by the factor “risk of runoff”, which was derived from a runoff-model (rainfall induced surface runoff). Multivariate analysis explained 39.9% of the variance in species number, revealing stream width as the most important factor (25.3%) followed by risk of runoff (9.7%). The results showed that wider streams – with or without agricultural stressors - contained significantly higher species numbers than smaller streams. This can be explained by potentially more diverse in-stream structures leading to more habitats and niches. However, negative effects on species number owing to runoff from arable land could be distinguished from the effect of stream width: the number of species within each stream width class significantly decreased with increasing risk of runoff. Therefore the factor “risk of runoff” is considered to express a significant proportion of the variability in macroinvertebrate communities caused by stressors of agricultural origin.

Keywords: land use, runoff, agriculture, macroinvertebrates

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Probst, M. 2005. "Simulation and assessment of pesticide entries into small
streams on a landscape level". Dissertation, Department 7: Environmental sciences at the University Koblenz-Landau, Campus Landau. 139 S. Download link http://kola.opus.hbz-nrw.de/frontdoor.php?source_opus=24 (Library of the University Koblenz-Landau).

Summary

The estimation of the potential risk of pesticide entries into streams - and therefore the potential
risk for the ecosystems - is an important requirement for the planning of risk mitigation
strategies. Especially on the landscape level the required event triggered sampling methods are
conjuncted with considerable efforts with regard to input data, time and personnel. To circumvent
these problems simulation models form a reasonable alternative.

The aims of this work were

(A) the development of a simulation tool for the estimation of pesticide entries into surface waters
on the landscape level, and

(B) the application of the simulator for an exposure- and risk-assessment as well as the assessment
of negative effects of pesticides on aquatic communities.


Section 1 - Exposure-, Risk- and Effects

In sections 1.1 and 1.2 the simulation model was applied to a multitude of small and medium sized
streams in an agricultural impacted study area around the city of Braunschweig, Germany. Section 1.3
gives an overview of the simulators field of application and the general system structure.

Section 1.1 - Scenario based simulation of runoff-related pesticide entries into small streams on a
landscape level (English publication, p. 27): In this paper we present a simulation tool for the
simulation of pesticide entry from arable land into adjacent streams. We used the ratio of exposure
to toxicity (REXTOX) model proposed by the OECD which was extended to calculate pesticide
concentrations in adjacent streams. We simulated the pesticide entry on the landscape level at 737
sites in small streams situated in the central lowland of Germany. The most significant model
parameters were the width of the no-application-zone and the degree of plant-interception. The
simulation was carried out using eight different environmental scenarios, covering variation of the
width of the no-application-zone, climate and seasonal scenarios. The highest in-stream
concentrations were predicted at a scenario using no (0 m) buffer zone in conjunction with increased
precipitation. According to the predicted concentrations, the risk for the aquatic communities was
estimated based on standard toxicity tests and the application of a safety factor. The simulation
results are presented by means of risk maps for numerous sites under varying scenarios as well as by
case study diagrams with focus on the model behavior under the influence of single parameters. Risk
maps confirmed the importance of no-application zones for the levels of pesticide input. They also
indicated the importance of the existing no-application zones for certain compounds - and in some
cases the need for a further evaluation of these regulations.

Section 1.2 - Linking land use variables and invertebrate taxon richness in small and medium-sized
agricultural streams on a landscape level (English publication, p. 50): In this study the average
numbers of invertebrate species across an arable landscape in central Germany (surveys from 15 years
in 90 streams at 202 sites) were assessed for their correlation with environmental factors such as
stream width, land use (arable land, forest, pasture, settlement), soil type and agricultural
derived stressors. The stress originating from arable land was estimated by the factor "risk of
runoff", which was derived from a runoff-model (rainfall induced surface runoff). Multivariate
analysis explained 39.9% of the variance in species number, revealing stream width as the most
important factor (25.3%) followed by risk of runoff (9.7%). The results showed that wider streams -
with or without agricultural stressors - contained significantly higher species numbers than smaller
streams. This can be explained by potentially more diverse in-stream structures leading to more
habitats and niches. However, negative effects on species number owing to runoff from arable land
could be distinguished from the effect of stream width: the number of species within each stream
width class significantly decreased with increasing risk of runoff. The factor "risk of runoff" is
considered to express a significant proportion of the variability in macroinvertebrate communities
caused by stressors of agricultural origin.

Section 1.3 - Informationssystem zur ökotoxikologischen Bewertung der Gewässergüte in Bezug auf
Pflanzenschutzmitteleinträge aus der Landwirtschaft - Systemaufbau und Anwendungsmöglichkeiten
(German publication, p. 61): Section 1.3 contains a short overview of the simulation tool, the field
of application and some examples of use, covering the effects of the width of the buffer zone as
well as the creation of risk maps on the landscape level.

Section 2 - The simulation tool

An important aspect for the employment of a simulation model in the context of risk assessment is
the applicability in practice: the accessibility of the needed input data, e.g. in digital form from
authorities and public institutions, the conversion of the mathematical model into a software
application that can be run on any current personnel computer and also an appropriate end-user
documentation of the system.

Section 1.4 - Informationssystem zur ökotoxikologischen Bewertung der Gewässergüte in Bezug auf
Pflanzenschutzmitteleinträge aus der Landwirtschaft - Simulationsmodell und Systemaufbau (German
report, p. 67): In this section a general overview of the simulation model as well as the schematic
system structure given.

Section 1.5 - Benutzerhandbuch (German report, p. 71): The user manual contains all relevant details
concerning the installation of the system, generation of the required input data via GIS or scenario
generator, and the general use of the system. Moreover it presents some application examples showing
the creation of GIS-risk maps in detail and planning of the effects of risk mitigation strategies
(what-if analyses).

Section 1.6 - Technical documentation (German report, p. 104): The technical documentation describes
internal structures and processes of the simulation system. Section 1.6 provides information
regarding the required structure of input tables, the usage and format of data sets obtained from
public sources, the data pre-processing steps via GIS, and the data-structures of the
scenario-generator application. Additionally the structures of all database tables used by the
simulator application are listed, the contents of the included installation cd-rom is documented and
the essential source code fragments and functions of the simulator application and of the
GIS-scripts are listed.

Keywords: risk assessment, pesticides, runoff, buffer zones, simulation, modeling, landscape level, climate
change, land use, agriculture, macroinvertebrates