Archaologen verwenden bei der Rekonstruktion der Lebensweise unserer Vorfahren auch die bei Ausgr... more Archaologen verwenden bei der Rekonstruktion der Lebensweise unserer Vorfahren auch die bei Ausgrabungen gefundenen Abfalle und Gebrauchsgegenstande. Die Scherben von Topferwaren hatten, auch wenn sie sich uber Jahrtausende nicht zersetzt haben, fur die Nachwelt keinen dauernden Schaden angerichtet.
A systematic state-wide inventory and evaluation of abandoned waste sites and contaminated land s... more A systematic state-wide inventory and evaluation of abandoned waste sites and contaminated land sites requires a complete assessment of all localities, a description of the site characteristics and of the geological and hydrogeological factors, in addition to data on the kind of wastes that were deposited. About 6000 abandoned waste sites are known in Lower Saxony. The large number demands a systematic and uniform treatment of data state-wide.
The present editorial 2020 continues the series of status reports in Environmental Earth Sciences... more The present editorial 2020 continues the series of status reports in Environmental Earth Sciences (EES) in previous years 2017 and 2019 (Kolditz et al. in Environ Earth Sci 77: 8, 2018, Kolditz et al. in Environ Earth Sci 79: 11, 2020). The year 2020 coming to an end was heavily influenced by the COVID-19 pandemic affecting all areas of life including research work and, therefore, scientific publishing as well (“Introduction”). One bright spot which shows longevity of journals that produce a quality product is that Environmental Earth Sciences (EES) is celebrating its 45th anniversary of publication. To this extent EES continues the tradition to honor the most cited papers contributing to the 2020 Impact Factor (IF) (“Highly and most cited topics”) and provide information on the current status of EES as well as an outlook to 2021 (“Progress report”)
The article deals with the GIS-based determination of the mean long term groundwater recharge in ... more The article deals with the GIS-based determination of the mean long term groundwater recharge in the Federal State of Lower Saxony making use of high-resolution digital data (Dorhofer et al. 2001). The model calculationswere performed on the basis of the water-balance model GROWA (Kunkel and Wendland 2002) with a spatial resolution of 100 m x 100 m. In the GROWA model total runoff is calculated by combining climatic, pedological and other site parameters with land use specific regression coefficients (DVWK 1996). The determination of the groundwater recharge is performed on the basis of a runoff separation, using static runoff fractions as a function of certain area properties such as hydrogeology and hill slope. A hierarchical approach is applied, i.e. only one is regarded as important for the groundwater runoff fraction. Other area properties are only considered if the primary area property is not relevant. The accuracy of the calculated ground-water recharge values was verified o...
KurzfassungDie flächenhafte Bedrohung der Trinkwasservorkommen durch Altlasten wird am Beispiel d... more KurzfassungDie flächenhafte Bedrohung der Trinkwasservorkommen durch Altlasten wird am Beispiel des Landes Niedersachsen dargelegt. Etwa 16% der über 8500 Altablagerungen liegen relativ gleichmäßig verteilt in Schutzgebieten. Altstandorte spiegeln im wesentlichen die Besiedlungsstruktur in den Einzugsgebieten wider; im Nahbereich von Bremen wurden fast zehn Verdachtsnutzungen pro km2 ermittelt. Zur Erstbewertung wurden vier hydrogeologische Lagetypen entwickelt, die den Bezug zwischen Altlastkörper und Förderniveau schematisiert darstellen. Schwerpunktuntersuchungsprogramme werden für Gebiete durchzuführen sein, die hohe Dichten von Altlasten mit Verdacht auf Sonderabfälle und mit ungünstigen Standortgegebenheiten aufweisen und große Versorgungsleistungen haben. Zur Beurteilung der konkreten Gefährdung sind Bewertungsverfahren weitgehend ungeeignet. Statt dessen müssen Gekoppelte Transportbetrachtungen unter Nutzung von Modellen und Geographischen Informationssystemen sowie Datenbanken vorgenommen werden, die die Betroffenheit potentieller Nutzer darlegen.AbstractData from Lower Saxony are used to exemplify the regional threat to drinking water resources issuing from abandoned landfills and contaminated land sites. Of more than 8500 abandoned landfills about 16% are situated within drinking water protection areas. The number and locations of contaminated industrial sites reflect the population density; about ten cases of documented hazardous production activities have been reported per km2 of protection area near the city of Bremen. For the preliminary assessment of hazards from contaminated sites, a scheme of four hydrogeological standard settings was developed that illustrates the relationship between the contaminant source and the groundwater abstraction horizon. Investigation programs must be concentrated in areas with a high density of abandoned landfills that contain hazardous waste and/or have unsuitable hydrogeological conditions and where there are large groundwater production capacities. For the evaluation of actual hazards, formalized evaluation procedures are not generally suitable. Instead, coupled-transport assessments must be conducted using transport models and geographical information systems to evaluate effects for potential users of groundwater.
Archaologen verwenden bei der Rekonstruktion der Lebensweise unserer Vorfahren auch die bei Ausgr... more Archaologen verwenden bei der Rekonstruktion der Lebensweise unserer Vorfahren auch die bei Ausgrabungen gefundenen Abfalle und Gebrauchsgegenstande. Die Scherben von Topferwaren hatten, auch wenn sie sich uber Jahrtausende nicht zersetzt haben, fur die Nachwelt keinen dauernden Schaden angerichtet.
A systematic state-wide inventory and evaluation of abandoned waste sites and contaminated land s... more A systematic state-wide inventory and evaluation of abandoned waste sites and contaminated land sites requires a complete assessment of all localities, a description of the site characteristics and of the geological and hydrogeological factors, in addition to data on the kind of wastes that were deposited. About 6000 abandoned waste sites are known in Lower Saxony. The large number demands a systematic and uniform treatment of data state-wide.
The present editorial 2020 continues the series of status reports in Environmental Earth Sciences... more The present editorial 2020 continues the series of status reports in Environmental Earth Sciences (EES) in previous years 2017 and 2019 (Kolditz et al. in Environ Earth Sci 77: 8, 2018, Kolditz et al. in Environ Earth Sci 79: 11, 2020). The year 2020 coming to an end was heavily influenced by the COVID-19 pandemic affecting all areas of life including research work and, therefore, scientific publishing as well (“Introduction”). One bright spot which shows longevity of journals that produce a quality product is that Environmental Earth Sciences (EES) is celebrating its 45th anniversary of publication. To this extent EES continues the tradition to honor the most cited papers contributing to the 2020 Impact Factor (IF) (“Highly and most cited topics”) and provide information on the current status of EES as well as an outlook to 2021 (“Progress report”)
The article deals with the GIS-based determination of the mean long term groundwater recharge in ... more The article deals with the GIS-based determination of the mean long term groundwater recharge in the Federal State of Lower Saxony making use of high-resolution digital data (Dorhofer et al. 2001). The model calculationswere performed on the basis of the water-balance model GROWA (Kunkel and Wendland 2002) with a spatial resolution of 100 m x 100 m. In the GROWA model total runoff is calculated by combining climatic, pedological and other site parameters with land use specific regression coefficients (DVWK 1996). The determination of the groundwater recharge is performed on the basis of a runoff separation, using static runoff fractions as a function of certain area properties such as hydrogeology and hill slope. A hierarchical approach is applied, i.e. only one is regarded as important for the groundwater runoff fraction. Other area properties are only considered if the primary area property is not relevant. The accuracy of the calculated ground-water recharge values was verified o...
KurzfassungDie flächenhafte Bedrohung der Trinkwasservorkommen durch Altlasten wird am Beispiel d... more KurzfassungDie flächenhafte Bedrohung der Trinkwasservorkommen durch Altlasten wird am Beispiel des Landes Niedersachsen dargelegt. Etwa 16% der über 8500 Altablagerungen liegen relativ gleichmäßig verteilt in Schutzgebieten. Altstandorte spiegeln im wesentlichen die Besiedlungsstruktur in den Einzugsgebieten wider; im Nahbereich von Bremen wurden fast zehn Verdachtsnutzungen pro km2 ermittelt. Zur Erstbewertung wurden vier hydrogeologische Lagetypen entwickelt, die den Bezug zwischen Altlastkörper und Förderniveau schematisiert darstellen. Schwerpunktuntersuchungsprogramme werden für Gebiete durchzuführen sein, die hohe Dichten von Altlasten mit Verdacht auf Sonderabfälle und mit ungünstigen Standortgegebenheiten aufweisen und große Versorgungsleistungen haben. Zur Beurteilung der konkreten Gefährdung sind Bewertungsverfahren weitgehend ungeeignet. Statt dessen müssen Gekoppelte Transportbetrachtungen unter Nutzung von Modellen und Geographischen Informationssystemen sowie Datenbanken vorgenommen werden, die die Betroffenheit potentieller Nutzer darlegen.AbstractData from Lower Saxony are used to exemplify the regional threat to drinking water resources issuing from abandoned landfills and contaminated land sites. Of more than 8500 abandoned landfills about 16% are situated within drinking water protection areas. The number and locations of contaminated industrial sites reflect the population density; about ten cases of documented hazardous production activities have been reported per km2 of protection area near the city of Bremen. For the preliminary assessment of hazards from contaminated sites, a scheme of four hydrogeological standard settings was developed that illustrates the relationship between the contaminant source and the groundwater abstraction horizon. Investigation programs must be concentrated in areas with a high density of abandoned landfills that contain hazardous waste and/or have unsuitable hydrogeological conditions and where there are large groundwater production capacities. For the evaluation of actual hazards, formalized evaluation procedures are not generally suitable. Instead, coupled-transport assessments must be conducted using transport models and geographical information systems to evaluate effects for potential users of groundwater.
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Papers by Gunter Dörhöfer