Affiner votre recherche
Résultats 1-10 de 10
Selective pressure on microbial communities in a drinking water aquifer – Geochemical parameters vs. micropollutants
2022
Aldas-Vargas, Andrea | Hauptfeld, Ernestina | Hermes, Gerben D.A. | Atashgahi, Siavash | Smidt, Hauke | Rijnaarts, Huub H.M. | Sutton, Nora B.
Groundwater quality is crucial for drinking water production, but groundwater resources are increasingly threatened by contamination with pesticides. As pesticides often occur at micropollutant concentrations, they are unattractive carbon sources for microorganisms and typically remain recalcitrant. Exploring microbial communities in aquifers used for drinking water production is an essential first step towards understanding the fate of micropollutants in groundwater. In this study, we investigated the interaction between groundwater geochemistry, pesticide presence, and microbial communities in an aquifer used for drinking water production. Two groundwater monitoring wells in The Netherlands were sampled in 2014, 2015, and 2016. In both wells, water was sampled from five discrete depths ranging from 13 to 54 m and was analyzed for geochemical parameters, pesticide concentrations and microbial community composition using 16S rRNA gene sequencing and qPCR. Groundwater geochemistry was stable throughout the study period and pesticides were heterogeneously distributed at low concentrations (μg L−1 range). Microbial community composition was also stable throughout the sampling period. Integration of a unique dataset of chemical and microbial data showed that geochemical parameters and to a lesser extent pesticides exerted selective pressure on microbial communities. Microbial communities in both wells showed similar composition in the deeper aquifer, where pumping results in horizontal flow. This study provides insight into groundwater parameters that shape microbial community composition. This information can contribute to the future implementation of remediation technologies to guarantee safe drinking water production.
Afficher plus [+] Moins [-]Selective pressure on microbial communities in a drinking water aquifer – Geochemical parameters vs. micropollutants
2022
Aldas-Vargas, Andrea | Hauptfeld, Ernestina | Hermes, Gerben D.A. | Atashgahi, Siavash | Smidt, Hauke | Rijnaarts, Huub H.M. | Sutton, Nora B.
Groundwater quality is crucial for drinking water production, but groundwater resources are increasingly threatened by contamination with pesticides. As pesticides often occur at micropollutant concentrations, they are unattractive carbon sources for microorganisms and typically remain recalcitrant. Exploring microbial communities in aquifers used for drinking water production is an essential first step towards understanding the fate of micropollutants in groundwater. In this study, we investigated the interaction between groundwater geochemistry, pesticide presence, and microbial communities in an aquifer used for drinking water production. Two groundwater monitoring wells in The Netherlands were sampled in 2014, 2015, and 2016. In both wells, water was sampled from five discrete depths ranging from 13 to 54 m and was analyzed for geochemical parameters, pesticide concentrations and microbial community composition using 16S rRNA gene sequencing and qPCR. Groundwater geochemistry was stable throughout the study period and pesticides were heterogeneously distributed at low concentrations (μg L−1 range). Microbial community composition was also stable throughout the sampling period. Integration of a unique dataset of chemical and microbial data showed that geochemical parameters and to a lesser extent pesticides exerted selective pressure on microbial communities. Microbial communities in both wells showed similar composition in the deeper aquifer, where pumping results in horizontal flow. This study provides insight into groundwater parameters that shape microbial community composition. This information can contribute to the future implementation of remediation technologies to guarantee safe drinking water production.
Afficher plus [+] Moins [-]Performance of faecal indicator bacteria, microbial source tracking, and pollution risk mapping in highland tropical water
2021
Goshu, G. | Koelmans, A.A. | de Klein, J.J.M.
Faecal indicator bacteria (FIB) are used for the assessment of faecal pollution and possible water quality deterioration. There is growing evidence that FIB used in temperate regions are not adequate and reliable to detect faecal pollution in tropical regions. Hence, this study evaluated the adequacy of FIB, including total coliforms (TC), Escherichia coli (EC), Enterococci (IEC), and Clostridium perfringens (CP) in the high-altitude, tropical country of Ethiopia. In addition to FIB, for microbial source tracking (MST), a ruminant-associated molecular marker was applied at different water types and altitudes, and faecal pollution risk mapping was conducted based on consensus FIB. The performances of the indicators were evaluated at 22 sites from different water types. The results indicate that EC cell enumeration and CP spore determination perform well for faecal contamination monitoring. Most of the sub-basins of Lake Tana were found to be moderately to highly polluted, and the levels of pollution were demonstrated to be higher in the rainy season than in the post-rainy season. Markers associated with ruminants (BacR) were identified in more than three quarters of the sites. Moderate to high levels of faecal pollution were found in most sub-basins, and the highest levels were found during the rainy season. A bacterial pollution risk map was developed for sub-basins of Lake Tana, including the un-gauged sub-basins. We demonstrate how bacterial pollution risk mapping can aid in improvements to water quality testing and reduce risk to the general population from stream bacteria.
Afficher plus [+] Moins [-]Performance of faecal indicator bacteria, microbial source tracking, and pollution risk mapping in highland tropical water
2021
Goshu, G. | Koelmans, A.A. | de Klein, J.J.M.
Faecal indicator bacteria (FIB) are used for the assessment of faecal pollution and possible water quality deterioration. There is growing evidence that FIB used in temperate regions are not adequate and reliable to detect faecal pollution in tropical regions. Hence, this study evaluated the adequacy of FIB, including total coliforms (TC), Escherichia coli (EC), Enterococci (IEC), and Clostridium perfringens (CP) in the high-altitude, tropical country of Ethiopia. In addition to FIB, for microbial source tracking (MST), a ruminant-associated molecular marker was applied at different water types and altitudes, and faecal pollution risk mapping was conducted based on consensus FIB. The performances of the indicators were evaluated at 22 sites from different water types. The results indicate that EC cell enumeration and CP spore determination perform well for faecal contamination monitoring. Most of the sub-basins of Lake Tana were found to be moderately to highly polluted, and the levels of pollution were demonstrated to be higher in the rainy season than in the post-rainy season. Markers associated with ruminants (BacR) were identified in more than three quarters of the sites. Moderate to high levels of faecal pollution were found in most sub-basins, and the highest levels were found during the rainy season. A bacterial pollution risk map was developed for sub-basins of Lake Tana, including the un-gauged sub-basins. We demonstrate how bacterial pollution risk mapping can aid in improvements to water quality testing and reduce risk to the general population from stream bacteria.
Afficher plus [+] Moins [-]Heavy metals in allotment gardens close to an oil refinery in Plock
1997
Mikula, W. (Warsaw Agricultural Univ., Warszawa (Poland). Faculty of Horticulture, Dept. of Environmental Protection) | Indeka, L.
Sorption and desorption of diuron and norflurazon in Florida citrus soils
1992
Reddy, K.N. (Florida Univ., Alfred, FL (USA). Citrus Research and Education Center) | Singh, M. | Alva, A.K.
Background concentration ranges of heavy metals in Swedish groundwaters from crystalline rocks: a review
1989
Ledin, A. (Linkoeping Univ. (Sweden). Dept. of Water and Environmental Studies) | Pettersson, C. | Allard, B. | Aastrup, M.
Potential hazards of lime application in a damaged pine forest ecosystem in Berlin, Germany
1989
Marschner, B. (Technical Univ. Berlin (Germany). Dept. of Soil Science) | Stahr, K. | Renger, M.
Assessment of the bacteriological quality of rural groundwater supplies in northern West Virginia
1987
Sworobuk, J.E. (West Virginia Univ., Morgantown, WV (USA). Div. of Plant and Soil Sciences) | Law, C.B. | Bissonnette, G.K.
Cyanogen accumulation in environment during processing of cassava (Manihot esculenta Crantz) for starch and sago
1998
Balagopalan, C. (Central Tuber Crops Research Inst., Trivandrum, Kerala (India). Div. of Crop Utilization and Biotechnology) | Rajalakshmy, L.