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Khandelwal A, Castillo T, González-Pinzón R. Evidence of deviations between experimental and empirical mixing lengths: Multi-discharge field tests in an arid river system. Water Res 2024; 256:121629. [PMID: 38643642 DOI: 10.1016/j.watres.2024.121629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 04/04/2024] [Accepted: 04/16/2024] [Indexed: 04/23/2024]
Abstract
Despite advances in wastewater treatment plant (WWTP) efficiencies, multiple contaminants of concern, such as microplastics, pharmaceuticals, and per- and poly-fluoroalkyl substances (PFAS) remain largely untreated near discharge points and can be highly concentrated before they are fully mixed within the receiving river. Environmental agencies enforce mixing zone permits for the temporary exceedance of water quality parameters beyond targeted control levels under the assumption that contaminants are well-mixed and diluted downstream of mixing lengths, which are typically quantified using empirical equations derived from one-dimensional transport models. Most of these equations were developed in the 1970s and have been assumed to be standard practice since then. However, their development and validation lacked the technological advances required to test them in the field and under changing flow conditions. While new monitoring techniques such as remote sensing and infrared imaging have been employed to visualize mixing lengths and test the validity of empirical equations, those methods cannot be easily repeated due to high costs or flight restrictions. We investigated the application of Lagrangian and Eulerian monitoring approaches to experimentally quantify mixing lengths downstream of a WWTP discharging into the Rio Grande near Albuquerque, New Mexico (USA). Our data spans river to WWTP discharges ranging between 2-22x, thus providing a unique dataset to test long-standing empirical equations in the field. Our results consistently show empirical equations could not describe our experimental mixing lengths. Specifically, while our experimental data revealed "bell-shaped" mixing lengths as a function of increasing river discharges, all empirical equations predicted monotonically increasing mixing lengths. Those mismatches between experimental and empirical mixing lengths are likely due to the existence of threshold processes defining mixing at different flow regimes, i.e., jet diffusion at low flows, the Coanda effect at intermediate flows, and turbulent mixing at higher flows, which are unaccounted for by the one-dimensional empirical formulas. Our results call for a review of the use of empirical mixing lengths in streams and rivers to avoid widespread exposures to emerging contaminants.
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Affiliation(s)
- Aashish Khandelwal
- Gerald May Department of Civil, Construction and Environmental Engineering, University of New Mexico, Albuquerque, NM USA
| | - Tzion Castillo
- Gerald May Department of Civil, Construction and Environmental Engineering, University of New Mexico, Albuquerque, NM USA; Electrical Engineering, University of New Mexico, Albuquerque, NM USA
| | - Ricardo González-Pinzón
- Gerald May Department of Civil, Construction and Environmental Engineering, University of New Mexico, Albuquerque, NM USA.
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2
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Martin NA, Sala-Comorera L, Gao G, Corkery A, Reynolds LJ, Nolan TM, Whitty M, O'Sullivan JJ, Meijer WG. Inclusion of hydrodynamic properties of bathing waters is critical in selecting faecal indicators to assess public health impacts of faecal contamination. Water Res 2023; 242:120137. [PMID: 37300999 DOI: 10.1016/j.watres.2023.120137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 05/26/2023] [Accepted: 05/27/2023] [Indexed: 06/12/2023]
Abstract
The EU Bathing Water Directive (BWD) requires member states to assess bathing water quality according to the levels of faecal indicator bacteria (FIB) in designated bathing areas. However, this criterion has two significant limitations given that the BWD does not; (i) account for differences in hydrodynamic properties of bathing waters and, (ii) assumes that all faecal pathogens decay equally in aquatic environments. This study simulated sewage discharge events in three hypothetical aquatic environments characterised by different advection and dispersion parameters in the solute transport equation. Temporal changes in the downstream concentration of six faecal indicators were determined in simulations that utilised measured decay rates of each faecal indicator from a programme of controlled microcosm experiments in fresh and seawater environments. The results showed that the decay rates of faecal indicators are not a critical parameter in advection dominant water bodies, such as in fast-flowing rivers. Therefore, faecal indicator selection is less important in such systems and for these, FIB remains the most cost-effective faecal indicator to monitor the public health impacts of faecal contamination. In contrast, consideration of faecal indicator decay is important when assessing dispersion and advection/dispersion dominant systems, which would pertain to transitional (estuarine) and coastal waterbodies. Results suggest that the inclusion of viral indicators, such as crAssphage and PMMoV, could improve the reliability of water quality modelling and minimise the risk of waterborne illnesses from faecal contamination.
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Affiliation(s)
- Niamh A Martin
- UCD School of Biomolecular and Biomedical Science, UCD Earth Institute and UCD Conway Institute, University College Dublin, Dublin 4, Ireland
| | - Laura Sala-Comorera
- UCD School of Biomolecular and Biomedical Science, UCD Earth Institute and UCD Conway Institute, University College Dublin, Dublin 4, Ireland
| | - Guanghai Gao
- UCD School of Civil Engineering, UCD Dooge Centre for Water Resources Research and UCD Earth Institute, University College Dublin, Dublin 4, Ireland
| | - Aisling Corkery
- UCD School of Civil Engineering, UCD Dooge Centre for Water Resources Research and UCD Earth Institute, University College Dublin, Dublin 4, Ireland
| | - Liam J Reynolds
- UCD School of Biomolecular and Biomedical Science, UCD Earth Institute and UCD Conway Institute, University College Dublin, Dublin 4, Ireland
| | - Tristan M Nolan
- UCD School of Biomolecular and Biomedical Science, UCD Earth Institute and UCD Conway Institute, University College Dublin, Dublin 4, Ireland
| | - Megan Whitty
- UCD School of Biomolecular and Biomedical Science, UCD Earth Institute and UCD Conway Institute, University College Dublin, Dublin 4, Ireland
| | - John J O'Sullivan
- UCD School of Civil Engineering, UCD Dooge Centre for Water Resources Research and UCD Earth Institute, University College Dublin, Dublin 4, Ireland
| | - Wim G Meijer
- UCD School of Biomolecular and Biomedical Science, UCD Earth Institute and UCD Conway Institute, University College Dublin, Dublin 4, Ireland.
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3
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Drzymała J, Kalka J, Sochacki A, Felis E. Towards Sustainable Wastewater Treatment: Bioindication as a Technique for Supporting Treatment Efficiency Assessment. Int J Environ Res Public Health 2022; 19:11859. [PMID: 36231168 PMCID: PMC9565086 DOI: 10.3390/ijerph191911859] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Revised: 09/07/2022] [Accepted: 09/18/2022] [Indexed: 06/16/2023]
Abstract
Constructed wetlands (CWs) are a promising alternative for conventional methods of wastewater treatment. However, the biggest challenge in wastewater treatment is the improvement of the technology used so that it is possible to remove micropollutants without additional costs. The impact of wastewater treatment in CWs on toxicity towards Aliivibrio fischeri, Daphnia magna and Lemna minor was investigated. The effects of feeding regime (wastewater fed in five batches per week at a batch volume of 1 L, or twice per week at a batch volume of 2.5 L) and the presence of pharmaceuticals (diclofenac and sulfamethoxazole), as well as the presence of Miscantus giganteus plants in CW columns (twelve of the 24 columns that were planted) were analyzed. A reduction in toxicity was observed in all experimental setups. The effluents from constructed wetlands were classified as moderately toxic (average TU for A. fischeri, D. magna and L. minor was 0.9, 2.5 and 5.5, respectively). The feeding regime of 5 days of feeding/2 days of resting resulted in a positive impact on the ecotoxicological and chemical parameters of wastewater (removal of TOC, N-NH4 and pharmaceuticals). Extended exposure of Miscantus giganteus to the wastewater containing pharmaceuticals resulted in elevated activity of antioxidant enzymes (catalase and superoxide dismutase) in leaf material.
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Affiliation(s)
- Justyna Drzymała
- The Biotechnology Centre, Silesian University of Technology, 44-100 Gliwice, Poland
| | - Joanna Kalka
- Environmental Biotechnology Department, Faculty of Energy and Environmental Engineering, Silesian University of Technology, Akademicka str 2A, 44-100 Gliwice, Poland
| | - Adam Sochacki
- Environmental Biotechnology Department, Faculty of Energy and Environmental Engineering, Silesian University of Technology, Akademicka str 2A, 44-100 Gliwice, Poland
- Department of Applied Ecology, Faculty of Environmental Sciences, Czech University of Life Sciences Prague, 16500 Prague, Czech Republic
| | - Ewa Felis
- Environmental Biotechnology Department, Faculty of Energy and Environmental Engineering, Silesian University of Technology, Akademicka str 2A, 44-100 Gliwice, Poland
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4
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Afolabi EO, Quilliam RS, Oliver DM. Time since faecal deposition influences mobilisation of culturable E. coli and intestinal enterococci from deer, goose and dairy cow faeces. PLoS One 2022; 17:e0274138. [PMID: 36054151 PMCID: PMC9439212 DOI: 10.1371/journal.pone.0274138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Accepted: 07/25/2022] [Indexed: 11/18/2022] Open
Abstract
Mobilisation is a term used to describe the supply of a pollutant from its environmental source, e.g., soil or faeces, into a hydrological transfer pathway. The overarching aim of this study was to determine, using a laboratory-based approach, whether faecal indicator bacteria (FIB) are hydrologically mobilised in different quantities from a typical agricultural, wildlife and wildfowl source, namely dairy cattle, red deer and greylag goose faeces. The mobilisation of FIB from fresh and ageing faeces under two contrasting temperatures was determined, with significant differences in the concentrations of both E. coli and intestinal enterococci lost from all faecal sources. FIB mobilisation from these faecal matrices followed the order of dairy cow > goose > deer (greatest to least, expressed as a proportion of the total FIB present). Significant changes in mobilisation rates from faecal sources over time were also recorded and this was influenced by the temperature at which the faecal material had aged over the course of the 12-day study. Characterising how indicators of waterborne pathogens are mobilised in the environment is of fundamental importance to inform models and risk assessments and develop effective strategies for reducing microbial pollution in catchment drainage waters and associated downstream impacts. Our findings add quantitative evidence to support the understanding of FIB mobilisation potential from three important faecal sources in the environment.
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Affiliation(s)
- Emmanuel O. Afolabi
- Faculty of Natural Sciences, Biological & Environmental Sciences, University of Stirling, Stirling, United Kingdom
| | - Richard S. Quilliam
- Faculty of Natural Sciences, Biological & Environmental Sciences, University of Stirling, Stirling, United Kingdom
| | - David M. Oliver
- Faculty of Natural Sciences, Biological & Environmental Sciences, University of Stirling, Stirling, United Kingdom
- * E-mail:
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5
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Drummond JD, Bernal S, Meredith W, Schumer R, Martí E. Stream Hydrology Controls the Longitudinal Bioreactive Footprint of Urban-Sourced Fine Particles. Environ Sci Technol 2022; 56:9083-9091. [PMID: 35671404 PMCID: PMC9228078 DOI: 10.1021/acs.est.2c00876] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Revised: 05/20/2022] [Accepted: 05/23/2022] [Indexed: 06/15/2023]
Abstract
The relevance of wastewater treatment plant (WWTP) effluents in fluvial networks is increasing as urbanization grows in catchments. Urban-sourced fine particles from WWTP effluents deposit and accumulate in the streambed sediment of receiving streams over time and can fuel respiration rates, which can thus potentially increase rates of biogeochemical reactions and CO2 emissions to the atmosphere. We aimed to provide a quantitative assessment of the influence of WWTP-sourced fine particles deposited in the streambed sediment on stream metabolic activity for 1 year in an intermittent Mediterranean stream. More nutrient-rich and metabolically active fine particle standing stocks were observed downstream of the WWTP, propagating to the end of the 820 m study reach, especially during the dry period (i.e., when the dilution capacity of the stream to WWTP inputs is <40%). Based on the longitudinal patterns of fine particle standing stocks and their metabolic activity, we estimated that the in-stream bioreactive capacity associated with these fine particles could potentially lead to substantial carbon dioxide emissions to the atmosphere (3.1 g C/m2/d). We show the importance of incorporating fine particle standing stocks downstream of point source inputs, particularly WWTPs in intermittent streams, into carbon budgets.
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Affiliation(s)
- Jennifer D. Drummond
- Integrative
Freshwater Ecology Group, Centre for Advanced
Studies of Blanes (CEAB-CSIC), Blanes, Girona 17300, Spain
- School
of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston B15 2TT, U.K.
| | - Susana Bernal
- Integrative
Freshwater Ecology Group, Centre for Advanced
Studies of Blanes (CEAB-CSIC), Blanes, Girona 17300, Spain
| | - Warren Meredith
- Integrative
Freshwater Ecology Group, Centre for Advanced
Studies of Blanes (CEAB-CSIC), Blanes, Girona 17300, Spain
- Center
for Geology and Environmental Cartography (Geocamb), University of Girona, Girona 17003, Spain
| | - Rina Schumer
- Division
of Hydrologic Sciences, Desert Research
Institute, Reno, Nevada 89512, United States
| | - Eugènia Martí
- Integrative
Freshwater Ecology Group, Centre for Advanced
Studies of Blanes (CEAB-CSIC), Blanes, Girona 17300, Spain
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6
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Castelar S, Bernal S, Ribot M, Merbt SN, Tobella M, Sabater F, Ledesma JLJ, Guasch H, Lupon A, Gacia E, Drummond JD, Martí E. Wastewater treatment plant effluent inputs influence the temporal variability of nutrient uptake in an intermittent stream. Urban Ecosyst. [DOI: 10.1007/s11252-022-01228-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
AbstractWastewater treatment plant (WWTP) effluents alter water chemistry and in-stream nutrient uptake rates of receiving freshwaters, thus changing the magnitude and fate of the nutrients exported. In Mediterranean regions, the dilution capacity of receiving streams can vary strongly over time due to the seasonal occurrence of floods and droughts, causing temporal variability of nutrient uptake. We assessed the temporal patterns and the controlling factors of net nutrient uptake in an intermittent Mediterranean stream receiving WWTP effluent inputs. We compiled the longitudinal concentration profiles of ambient dissolved inorganic nitrogen (DIN) and soluble reactive phosphorus (SRP) along a 800 m reach on 47 sampling dates between 2001 and 2017, encompassing a wide range of hydrological conditions. We estimated net nutrient uptake in the receiving stream. In 72% of the dates, high rates of net ammonium uptake co-occurred with net releases of either nitrate or nitrite. This pattern suggests that the receiving stream has a high nitrification capacity. Conversely, 75% of the dates did not show any longitudinal pattern in SRP concentration, suggesting that uptake and release processes for this element were either counterbalanced or both occurred at very low rates. Finally, net ammonium uptake was low when the stream had a low dilution capacity (< 40%) and ammonium concentration was high. Overall, we demonstrate that consideration of the receiving stream’s dilution capacity is imperative to the management of freshwaters to guarantee an adequate dilution of WWTP effluent inputs and avoid saturation of in-stream nutrient uptake capacity under low flow conditions in urban landscapes.
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7
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O'Donoghue C, Meng Y, Ryan M, Kilgarriff P, Zhang C, Bragina L, Daly K. Trends and influential factors of high ecological status mobility in Irish Rivers. Sci Total Environ 2022; 816:151570. [PMID: 34767885 DOI: 10.1016/j.scitotenv.2021.151570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 11/05/2021] [Accepted: 11/05/2021] [Indexed: 06/13/2023]
Abstract
The decline in high ecological water status in rivers is a significant concern in European countries. It is thus important to investigate the factors that cause sites to lose high status in order to undertake measures to protect and restore high status water quality. Analysis of 20 years of water quality data reveals strong mobility between high status and non-high status (especially good status) rivers. Associations between this mobility and socio-economic and physical environmental variables were estimated by multinomial logistic regression at national scale and regional scale. Based on reported changes in water quality status cross across 1990, 2000 and 2010, four classes of the mobility of high status were defined in this study: those sites that maintain high status (maintain), enter high status (enter), fluctuate between high and non-high status (fluctuate) and exit from high status (exit). The national results indicate that agricultural activity as indicated by variables representing intensity of livestock farming (organic nitrogen) and tillage farming (cereal share) and elevation had significant negative impacts on high status rivers. Meanwhile, significant differences in population density and septic tank density between 'exit', 'maintain', 'fluctuate' and 'enter' classes indicate that these factors played important roles in the stability of high status rivers. The regional outcomes reveal differential significant pressures across regions. For example, rainfall and elevation had positive impacts on high status rivers in the north-west region, while organic nitrogen had a negative effect in the south-west. This paper demonstrates the challenge in achieving the Water Framework Directive goal of maintaining high status rivers, given the sensitive and highly differentiated nature of areas that have lost high status or fluctuated in and out of high status. This paper also suggests the necessity for localised policies and mitigation measures.
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Affiliation(s)
| | - Yuting Meng
- Teagasc, Agriculture and Food Development Authority, Ireland.
| | - Mary Ryan
- Teagasc, Agriculture and Food Development Authority, Ireland
| | - Paul Kilgarriff
- Luxembourg Institute for Socio Economic Research, Luxembourg
| | - Chaosheng Zhang
- Teagasc, Agriculture and Food Development Authority, Ireland
| | - Lyubov Bragina
- Teagasc, Agriculture and Food Development Authority, Ireland
| | - Karen Daly
- Teagasc, Agriculture and Food Development Authority, Ireland
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8
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Tiirik K, Nõlvak H, Truu M, Peeb A, Kõiv-vainik M, Truu J. The Effect of the Effluent from a Small-Scale Conventional Wastewater Treatment Plant Treating Municipal Wastewater on the Composition and Abundance of the Microbial Community, Antibiotic Resistome, and Pathogens in the Sediment and Water of a Receiving Stream. Water 2021; 13:865. [DOI: 10.3390/w13060865] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The effluents of wastewater treatment plants (WWTPs) are major contributors of nutrients, microbes—including those carrying antibiotic resistance genes (ARGs)—and pathogens to receiving waterbodies. The effect of the effluent of a small-scale activated sludge WWTP treating municipal wastewater on the composition and abundance of the microbial community as well as the antibiotic resistome and pathogens in the sediment and water of the receiving stream and river was studied using metagenome sequencing and a quantitative approach. Elevated Bacteroidetes proportions in the prokaryotic community, heightened sulfonamide and aminoglycoside resistance determinants proportions, and an increase of up to three orders of magnitude of sul1–sul2–aadA–blaOXA2 gene cluster abundances were recorded in stream water and sediments 0.3 km downstream of a WWTP discharge point. Further downstream, a gradual recovery of affected microbial communities along a distance gradient from WWTP was recorded, culminating in the mostly comparable state of river water and sediment parameters 3.7 km downstream of WWTP and stream water and sediments upstream of the WWTP discharge point. Archaea, especially Methanosarcina, Methanothrix, and Methanoregula, formed a substantial proportion of the microbial community of WWTP effluent as well as receiving stream water and sediment, and were linked to the spread of ARGs. Opportunistic environmental-origin pathogens were predominant in WWTP effluent and receiving stream bacterial communities, with Citrobacter freundii proportion being especially elevated in the close vicinity downstream of the WWTP discharge point.
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Paruch L, Paruch AM. Cross-tracking of faecal pollution origins, macronutrients, pharmaceuticals and personal care products in rural and urban watercourses. Water Sci Technol 2021; 83:610-621. [PMID: 33600365 DOI: 10.2166/wst.2020.603] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
This study describes microbial and chemical source tracking approaches for water pollution in rural and urban catchments. Culturable faecal indicator bacteria, represented by Escherichia coli, were quantified. Microbial source tracking (MST) using host-specific DNA markers was applied to identify the origins of faecal contamination. Chemical source tracking (CST) was conducted to determine contaminants of emerging concern (CEC) of human/anthropogenic origin, including pharmaceuticals and personal care products (PPCPs) and endocrine-disrupting chemicals (EDCs). In addition, the eutrophication-causing macronutrients nitrogen and phosphorus were studied. MST tests revealed both anthropogenic and zoogenic faecal origins, with a dominance of human sources in the urban stream; non-human/environmental sources were prevalent in the rural creek. CST analyses revealed a higher number of CECs in the urban stream than in the rural watercourse. Positive correlations between PPCPs and both E. coli and the human DNA marker were uncovered in the urban stream, while in the rural creek, PPCPs were only highly correlated with the anthropogenic marker. Interestingly, macronutrients were strongly associated with primary faecal pollution origins in both watercourses. This correlation pattern determines the main pollutant contributors (anthropogenic or zoogenic) to eutrophication.
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Affiliation(s)
- Lisa Paruch
- Division of Environment and Natural Resources, Norwegian Institute of Bioeconomy Research (NIBIO), Oluf Thesens vei 43, 1433 Ås, Norway E-mail:
| | - Adam M Paruch
- Division of Environment and Natural Resources, Norwegian Institute of Bioeconomy Research (NIBIO), Oluf Thesens vei 43, 1433 Ås, Norway E-mail:
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10
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Ballesté E, Demeter K, Masterson B, Timoneda N, Sala-Comorera L, Meijer WG. Implementation and integration of microbial source tracking in a river watershed monitoring plan. Sci Total Environ 2020; 736:139573. [PMID: 32474276 DOI: 10.1016/j.scitotenv.2020.139573] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Revised: 05/17/2020] [Accepted: 05/18/2020] [Indexed: 05/20/2023]
Abstract
Fecal pollution of water bodies poses a serious threat for public health and ecosystems. Microbial source tracking (MST) is used to track the source of this pollution facilitating better management of pollution at the source. In this study we tested 12 MST markers to track human, ruminant, sheep, horse, pig and gull pollution to assess their usefulness as an effective management tool of water quality. First, the potential of the selected markers to track the source was evaluated using fresh fecal samples. Subsequently, we evaluated their performance in a catchment with different impacts, considering land use and environmental conditions. All MST markers showed high sensitivity and specificity, although none achieved 100% for both. Although some of the MST markers were detected in hosts other than the intended ones, their abundance in the target group was always several orders of magnitude higher than in the non-target hosts, demonstrating their suitability to distinguish between sources of pollution. The MST analysis matched the land use in the watershed allowing an accurate assessment of the main sources of pollution, in this case mainly human and ruminant pollution. Correlating environmental parameters including temperature and rainfall with MST markers provided insight into the dynamics of the pollution in the catchment. The levels of the human marker showed a significant negative correlation with rainfall in human polluted areas suggesting a dilution of the pollution, whereas at agricultural areas the ruminant marker increased with rainfall. There were no seasonal differences in the levels of human marker, indicating human pollution as a constant pressure throughout the year, whereas the levels of the ruminant marker was influenced by the seasons, being more abundant in summer and autumn. MST analysis integrated with land use and environmental data can improve the management of fecal polluted areas and set up best practice.
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Affiliation(s)
- Elisenda Ballesté
- UCD School of Biomolecular and Biomedical Science, UCD Earth Institute, UCD Conway Institute, University College Dublin, Dublin, Ireland
| | - Katalin Demeter
- UCD School of Biomolecular and Biomedical Science, UCD Earth Institute, UCD Conway Institute, University College Dublin, Dublin, Ireland
| | - Bartholomew Masterson
- UCD School of Biomolecular and Biomedical Science, UCD Earth Institute, UCD Conway Institute, University College Dublin, Dublin, Ireland
| | - Natàlia Timoneda
- Computational Genomics Laboratory, Department of Genetics, Microbiology and Statistics, University of Barcelona, Barcelona, Catalonia, Spain
| | - Laura Sala-Comorera
- UCD School of Biomolecular and Biomedical Science, UCD Earth Institute, UCD Conway Institute, University College Dublin, Dublin, Ireland
| | - Wim G Meijer
- UCD School of Biomolecular and Biomedical Science, UCD Earth Institute, UCD Conway Institute, University College Dublin, Dublin, Ireland.
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