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Madureira KH, Ferreira V, Callisto M. Rehabilitation of tropical urban streams improves their structure and functioning. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 926:171935. [PMID: 38527547 DOI: 10.1016/j.scitotenv.2024.171935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Revised: 03/19/2024] [Accepted: 03/22/2024] [Indexed: 03/27/2024]
Abstract
Urban streams are affected by a complex combination of stressors, which modify physical habitat structure, flow regime, water quality, biological community composition, and ecosystem processes and services, thereby altering ecosystem structure and functioning. Rehabilitation projects have been undertaken in several countries to rehabilitate urban streams. However, stream rehabilitation is still rarely reported for neotropical regions. In addition, most studies focus on structural aspects, such as water quality, sediment control, and flood events, without considering ecosystem function indicators. Here, we evaluated the structure and functioning of three 15-y old rehabilitated urban stream sites in comparison with three stream sites in the best available ecological condition (reference), three sites with moderate habitat alteration, and three severely degraded sites. Compared to degraded streams, rehabilitated streams had higher habitat diversity, sensitive macroinvertebrate taxa richness, and biotic index scores, and lower biochemical oxygen demand, primary production, sediment deposition, and siltation. However, rehabilitated streams had higher primary production than moderate and reference streams, and lower canopy cover, habitat diversity, sensitive macroinvertebrate taxa richness, and biotic index scores than reference streams. These results indicate that rehabilitated streams have better structural and functional condition than degraded streams, but do not strongly differ from moderately altered streams, nor have they reached reference stream condition. Nonetheless, we conclude that rehabilitation is effective in removing streams from a degraded state by improving ecosystem structure and functioning. Furthermore, the combined use of functional and structural indicators facilitated an integrative assessment of stream ecological condition and distinguished stream conditions beyond those based on water quality indicators.
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Affiliation(s)
- Karoline H Madureira
- Universidade Federal de Minas Gerais, Instituto de Ciências Biológicas, Departamento de Genética, Ecologia e Evolução, Laboratório de Ecologia de Bentos, Avenida Antônio Carlos, 6627, CP 486, CEP 31270-901 Belo Horizonte, Minas Gerais, Brazil.
| | - Verónica Ferreira
- MARE - Marine and Environmental Sciences Centre, ARNET - Aquatic Research Network, Department of Life Sciences, University of Coimbra, Calçada Martim de Freitas, 3000-456 Coimbra, Portugal.
| | - Marcos Callisto
- Universidade Federal de Minas Gerais, Instituto de Ciências Biológicas, Departamento de Genética, Ecologia e Evolução, Laboratório de Ecologia de Bentos, Avenida Antônio Carlos, 6627, CP 486, CEP 31270-901 Belo Horizonte, Minas Gerais, Brazil.
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2
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Ostrowski A, Connolly RM, Brown CJ, Sievers M. Fluctuating fortunes: Stressor synchronicity and fluctuating intensity influence biological impacts. Ecol Lett 2022; 25:2611-2623. [PMID: 36217804 PMCID: PMC9828260 DOI: 10.1111/ele.14120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Revised: 08/22/2022] [Accepted: 09/07/2022] [Indexed: 01/12/2023]
Abstract
Ecosystems remain under enormous pressure from multiple anthropogenic stressors. Manipulative experiments evaluating stressor interactions and impacts mostly apply stressors under static conditions without considering how variable stressor intensity (i.e. fluctuations) and synchronicity (i.e. timing of fluctuations) affect biological responses. We ask how variable stressor intensity and synchronicity, and interaction type, can influence how multiple stressors affect seagrass. At the highest intensities, fluctuating stressors applied asynchronously reduced seagrass biomass 36% more than for static stressors, yet no such difference occurred for photosynthetic capacity. Testing three separate hypotheses to predict underlying drivers of differences in biological responses highlighted alternative modes of action dependent on how stressors fluctuated over time. Given that environmental conditions are constantly changing, assessing static stressors may lead to inaccurate predictions of cumulative effects. Translating multiple stressor experiments to the real world, therefore, requires considering variability in stressor intensity and the synchronicity of fluctuations.
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Affiliation(s)
- Andria Ostrowski
- Coastal and Marine Research Centre, Australian Rivers Institute, School of Environment and ScienceGriffith UniversityGold CoastQueenslandAustralia
| | - Rod M. Connolly
- Coastal and Marine Research Centre, Australian Rivers Institute, School of Environment and ScienceGriffith UniversityGold CoastQueenslandAustralia
| | - Christopher J. Brown
- Coastal and Marine Research Centre, Australian Rivers Institute, School of Environment and ScienceGriffith UniversityGold CoastQueenslandAustralia
| | - Michael Sievers
- Coastal and Marine Research Centre, Australian Rivers Institute, School of Environment and ScienceGriffith UniversityGold CoastQueenslandAustralia
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3
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Vendrell-Puigmitja L, Proia L, Espinosa C, Barral-Fraga L, Cañedo-Argüelles M, Osorio V, Casas C, Llenas L, Abril M. Hypersaline mining effluents affect the structure and function of stream biofilm. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 843:156966. [PMID: 35760177 DOI: 10.1016/j.scitotenv.2022.156966] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Revised: 06/21/2022] [Accepted: 06/21/2022] [Indexed: 06/15/2023]
Abstract
The salinisation of freshwater ecosystems is a global environmental problem that threatens biodiversity, ecosystem functioning and human welfare. The aim of this study was to investigate the potential impact of a realistic salinity gradient on the structure and functioning of freshwater biofilms. The salinity gradient was based on the real ion concentration of a mining effluent from an abandoned mine in Germany. We exposed biofilm from a pristine stream to 5 increasing salinities (3 to 100 g L-1) under controlled conditions in artificial streams for 21 days. We evaluated its functional (photosynthetic efficiency, nutrient uptake, and microbial respiration) and structural responses (community composition, algal biomass and diatom, cyanobacteria and green algae metrics) over time. Then we compared their responses with an unexposed biofilm used as control. The functionality and structure of the biofilm exposed to the different salinities significantly decreased after short-term and long-term exposure, respectively. The community composition shifted to a new stable state where the most tolerant species increased their abundances. At the same time, we observed an increase in the community tolerance (measured as Pollution-Induced Community Tolerance) along the salinity gradient. This study provides relevant information on the salt threshold concentrations that can substantially damage algal cells (i.e., between 15 and 30 g L-1). The results provide new insights regarding the response and adaptation of stream biofilm to salinity and its potential implications at the ecosystem level.
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Affiliation(s)
- Lidia Vendrell-Puigmitja
- BETA Tech Center, TECNIO Network, University of Vic-Central University of Catalonia, Ctra de Roda 70, 08500 Vic, Spain
| | - Lorenzo Proia
- BETA Tech Center, TECNIO Network, University of Vic-Central University of Catalonia, Ctra de Roda 70, 08500 Vic, Spain.
| | - Carmen Espinosa
- BETA Tech Center, TECNIO Network, University of Vic-Central University of Catalonia, Ctra de Roda 70, 08500 Vic, Spain; Aigües de Vic S.A., Carrer de la Riera, 08500 Vic, Spain
| | - Laura Barral-Fraga
- LDAR24-Laboratoire Départemental d'Analyse et de Recherche de la Dordogne, 24660 Coulounieix-Chamiers, France; Grup de recerca en Ecologia aquàtica continental (GRECO), Departament de Ciències Ambientals, Universitat de Girona, 17071 Girona, Spain
| | - Miguel Cañedo-Argüelles
- Institute of Environmental Assessment and Water Research (IDAEA-CSIC), Jordi Girona, 18-26, 08034 Barcelona, Spain; Grup de recerca FEHM (Freshwater Ecology, Hydrology and Management), Departament de Biologia Evolutiva, Ecologia i Ciències Ambientals, Institut de Recerca de l'Aigua (IdRA), Universitat de Barcelona, Barcelona, Spain
| | - Victoria Osorio
- Catalan Institute for Water Research (ICRA), Emili Grahit 101, 17003 Girona, Spain; Department of Chemistry, University of Girona, Maria Aurèlia Capmany 69, 17003 Girona, Spain
| | - Carme Casas
- BETA Tech Center, TECNIO Network, University of Vic-Central University of Catalonia, Ctra de Roda 70, 08500 Vic, Spain
| | - Laia Llenas
- BETA Tech Center, TECNIO Network, University of Vic-Central University of Catalonia, Ctra de Roda 70, 08500 Vic, Spain
| | - Meritxell Abril
- BETA Tech Center, TECNIO Network, University of Vic-Central University of Catalonia, Ctra de Roda 70, 08500 Vic, Spain
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4
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Carles L, Wullschleger S, Joss A, Eggen RIL, Schirmer K, Schuwirth N, Stamm C, Tlili A. Wastewater microorganisms impact microbial diversity and important ecological functions of stream periphyton. WATER RESEARCH 2022; 225:119119. [PMID: 36170769 DOI: 10.1016/j.watres.2022.119119] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 07/20/2022] [Accepted: 09/13/2022] [Indexed: 06/16/2023]
Abstract
Effluents of wastewater treatment plants can impact microbial communities in the receiving streams. However, little is known about the role of microorganisms in wastewater as opposed to other wastewater constituents, such as nutrients and micropollutants. We aimed therefore at determining the impact of wastewater microorganisms on the microbial diversity and function of periphyton, key microbial communities in streams. We used a flow-through channel system to grow periphyton upon exposure to a mixture of stream water and unfiltered or ultra-filtered wastewater. Impacts were assessed on periphyton biomass, activities and tolerance to micropollutants, as well as on microbial diversity. Our results showed that wastewater microorganisms colonized periphyton and modified its community composition, resulting for instance in an increased abundance of Chloroflexi and a decreased abundance of diatoms and green algae. This led to shifts towards heterotrophy, as suggested by the changes in nutrient stoichiometry and the increased mineralization potential of carbon substrates. An increased tolerance towards micropollutants was only found for periphyton exposed to unfiltered wastewater but not to ultra-filtered wastewater, suggesting that wastewater microorganisms were responsible for this increased tolerance. Overall, our results highlight the need to consider the role of wastewater microorganisms when studying potential impacts of wastewater on the receiving water body.
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Affiliation(s)
- Louis Carles
- Eawag: Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
| | - Simon Wullschleger
- Eawag: Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
| | - Adriano Joss
- Eawag: Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
| | - Rik I L Eggen
- Eawag: Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland; Department of Environmental Systems Science, ETH, Zürich, Switzerland
| | - Kristin Schirmer
- Eawag: Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland; Department of Environmental Systems Science, ETH, Zürich, Switzerland; School of Architecture, Civil and Environmental Engineering, EPFL Lausanne, Lausanne, Switzerland
| | - Nele Schuwirth
- Eawag: Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland; Department of Environmental Systems Science, ETH, Zürich, Switzerland
| | - Christian Stamm
- Eawag: Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
| | - Ahmed Tlili
- Eawag: Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland; Department of Environmental Systems Science, ETH, Zürich, Switzerland.
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5
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Richards S, Bidgood L, Watson H, Stutter M. Biogeochemical impacts of sewage effluents in predominantly rural river catchments: Are point source inputs distinct to background diffuse pollution? JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 311:114891. [PMID: 35305367 DOI: 10.1016/j.jenvman.2022.114891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Revised: 02/10/2022] [Accepted: 03/10/2022] [Indexed: 06/14/2023]
Abstract
Discharge of treated sewage effluent to rivers can degrade aquatic ecosystem quality, interacting with multiple stressors in the wider catchment. In predominantly rural catchments, the river reach influence of point source effluents is unknown relative to complex background pressures. We examined water column, sediment and biofilm biogeochemical water quality parameters along river transects (200 m upstream to 1 km downstream) during summer at five wastewater treatment works (WWTW) in Scotland. Treated sewage effluent (subset, n = 3) pollutant concentrations varied between sites. Downstream concentration profiles of water and sediment biogeochemical parameters showed complex spatial changes. A hypothesised point source signature of elevated concentrations of pollution immediately downstream of WWTW then a decaying pollution 'plume' did not commonly occur. Instead, elevated soluble reactive phosphorus (SRP), ammonium and coliforms (maximum 0.23 mgP/l, 0.33 mgN/l and >2 × 106 MPN/100 ml) occurred immediately downstream of two WWTW, whereas some downstream pollutant concentrations decreased. Microbial substrate respiration responses only differed 1 km downstream. Significantly greater concentrations of sediment metal occurred >500 m downstream, likely due to the redeposition of historic contaminated sediments. Significantly lowered chlorophyll-a downstream of one WWTW coincided with elevated metals, despite water SRP and sediment P increases. Overall, stress caused to microbes and algae by effluent contaminants outweighed the subsidy effect of WWTW nutrients. We observed variable effluent flows to the rivers limited localised pollution downstream of WWTW and overall influence of arable land cover on river water quality. Together, this challenges views of consistently discharging point sources impacting low dilution sensitive rivers in summer contrasting with 'diffuse' sources. Thus, river water column and benthic compartments are altered at varying scales by point source effluents in combination with rural catchment pollution sources, both discrete (e.g. farmyards and septic tanks) and diffuse.
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Affiliation(s)
- Samia Richards
- The James Hutton Institute, Craigiebuckler, Aberdeen, AB15 8QH, Scotland, UK.
| | - Lucy Bidgood
- University of Dundee, Nethergate, Dundee, DD1 4HN, Scotland, UK
| | - Helen Watson
- The James Hutton Institute, Craigiebuckler, Aberdeen, AB15 8QH, Scotland, UK
| | - Marc Stutter
- The James Hutton Institute, Craigiebuckler, Aberdeen, AB15 8QH, Scotland, UK; Lancaster Environment Centre, Lancaster University, Bailrigg, LA1 4YQ, UK
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6
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Hellmann L, Módenes AN, Schmitz APDO, Espinoza-Quiñones FR, Trigueros DEG, Sauer Pokrywiecki T, Klem Bohrer J, Oglio ICD, Tones ARM. Effect of elemental composition assigned to antrotopic pollution on the quality of the water and sediment of the Marrecas river (PR, Brazil) as highlighted by multivariate statistical analyses. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2022; 57:139-153. [PMID: 35156550 DOI: 10.1080/10934529.2022.2039551] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 12/22/2021] [Accepted: 01/04/2022] [Indexed: 06/14/2023]
Abstract
In recent years, several environmental pollutants have been monitored in surface waters and sediments. However, few studies apply multivariate statistics to identify the main components and correlate them temporally and spatially. In this sense, the present study sought to monitor the quality of water and sediments in the Rio Marrecas/Brazil, through the analysis of physicochemical parameters and trace elements, as well as to identifying sources of contamination, using multivariate statistics. For this purpose, sampling was carried out in nine locations for a period of 12 months. The Total Reflection X-ray Fluorescence (TXRF) technique was used to quantify the 15 elements identified in water and sediment samples. Through multivariate statistical analyses, the most significant elements, their correlations and possible pollutant sources were defined, and the pollution index (HPI) and assessment index (HEI) of heavy metals were applied. The parameters pH and BOD5 do not comply with Brazilian legislation. Based on PCA and Spearman correlation, there was strong evidence of contamination of the water naturally, composed of the elements Ti, V, Mn, Fe, and of anthropogenic origin composed of the elements Ca, Ni, Cu, Zn. These findings provide insights to determine the impacts of heavy metals on human health and the environment.
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Affiliation(s)
- Liliane Hellmann
- Postgraduate Program of Chemical Engineering, Universidade Estadual do Oeste do Paraná, Toledo, Paraná, Brazil
| | - Aparecido Nivaldo Módenes
- Postgraduate Program of Chemical Engineering, Universidade Estadual do Oeste do Paraná, Toledo, Paraná, Brazil
| | - Ana Paula de Oliveira Schmitz
- Graduation Department of Engineering, Universidade Tecnológica Federal do Paraná - UTFPR, Francisco Beltrão, Paraná, Brazil
| | | | | | - Ticiane Sauer Pokrywiecki
- Graduation Department of Engineering, Universidade Tecnológica Federal do Paraná - UTFPR, Francisco Beltrão, Paraná, Brazil
| | - Jaqueline Klem Bohrer
- Postgraduate Program of Environmental Engineering, Universidade Tecnológica Federal do Paraná - UTFPR, Francisco Beltrão, Paraná, Brazil
| | | | - Aline Raquel Müller Tones
- Federal University of Fronteira Sul, Water and Ecotoxicology Laboratory, Rua Jacob Reinaldo Haupenthal, Cerro Largo, Rio Grande do Sul, Brazil
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7
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Carles L, Wullschleger S, Joss A, Eggen RIL, Schirmer K, Schuwirth N, Stamm C, Tlili A. Impact of wastewater on the microbial diversity of periphyton and its tolerance to micropollutants in an engineered flow-through channel system. WATER RESEARCH 2021; 203:117486. [PMID: 34412020 DOI: 10.1016/j.watres.2021.117486] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 06/30/2021] [Accepted: 07/26/2021] [Indexed: 06/13/2023]
Abstract
Wastewater treatment plants (WWTPs) play an important role in retaining organic matter and nutrients but to a lesser extent micropollutants. Therefore, treated wastewater is recognized as a major source of multiple stressors, including complex mixtures of micropollutants. These can potentially affect microbial communities in the receiving water bodies and the ecological functions they provide. In this study, we evaluated in flow-through channels the consequences of an exposure to a mixture of stream water and different percentages of urban WWTP effluent, ranging from 0% to 80%, on the microbial diversity and function of periphyton communities. Assuming that micropollutants exert a selective pressure for tolerant microorganisms within communities, we further examined the periphyton sensitivity to a micropollutant mixture extracted from passive samplers that were immersed in the wastewater effluent. As well, micropollutants in water and in periphyton were comprehensively quantified. Our results show that micropollutants detected in periphyton differed from those found in water, both in term of concentration and composition. Especially photosystem II inhibitors accumulated in periphyton more than other pesticides. Although effects of other substances cannot be excluded, this accumulation may have contributed to the observed higher tolerance of phototrophic communities to micropollutants upon exposure to 30% and 80% of wastewater. On the contrary, no difference in tolerance was observed for heterotrophic communities. Exposure to the gradient of wastewater led to structural differences in both prokaryotic and eukaryotic communities. For instance, the relative abundance of cyanobacteria was higher with increasing percentage of wastewater effluent, whereas the opposite was observed for diatoms. Such results could indicate that differences in community structure do not necessarily lead to higher tolerance. This highlights the need to consider other wastewater constituents such as nutrients and wastewater-derived microorganisms that can modulate community structure and tolerance. By using engineered flow-through channels that mimic to some extent the required field conditions for the development of tolerance in periphyton, our study constitutes a base to investigate the mechanisms underlying the increased tolerance, such as the potential role of microorganisms originating from wastewater effluents, and different treatment options to reduce the micropollutant load in effluents.
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Affiliation(s)
- Louis Carles
- Eawag: Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
| | - Simon Wullschleger
- Eawag: Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
| | - Adriano Joss
- Eawag: Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
| | - Rik I L Eggen
- Eawag: Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland; Department of Environmental Systems Science, ETH, Zürich, Switzerland
| | - Kristin Schirmer
- Eawag: Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland; Institute of Biogeochemistry and Pollutant Dynamics, ETH Zürich, Zürich, Switzerland; School of Architecture, Civil and Environmental Engineering, EPFL Lausanne, Lausanne, Switzerland
| | - Nele Schuwirth
- Eawag: Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland; Institute of Biogeochemistry and Pollutant Dynamics, ETH Zürich, Zürich, Switzerland
| | - Christian Stamm
- Eawag: Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
| | - Ahmed Tlili
- Eawag: Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland.
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8
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Sabater S, Elosegi A, Ludwig R. Framing biophysical and societal implications of multiple stressor effects on river networks. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 753:141973. [PMID: 32906045 DOI: 10.1016/j.scitotenv.2020.141973] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 08/22/2020] [Accepted: 08/23/2020] [Indexed: 06/11/2023]
Abstract
Urbanization, agriculture, and the manipulation of the hydrological cycle are the main drivers of multiple stressors affecting river ecosystems across the world. Physical, chemical, and biological stressors follow characteristic patterns of occurrence, intensity, and frequency, linked to human pressure and socio-economic settings. The societal perception of stressor effects changes when moving from broad geographic regions to narrower basin or waterbody scales, as political and ecologically based perspectives change across scales. Current approaches relating the stressor effects on river networks and human societies fail to incorporate complexities associated to their co-occurrence, such as: i) the evidence that drivers can be associated to different stressors; ii) their intensity and frequency may differ across spatial and temporal scales; iii) their differential effects on biophysical receptors may be related to their order of occurrence; iv) current and legacy stressors may produce unexpected outcomes; v) the potentially different response of different biological variables to stressor combinations; vi) the conflicting effects of multiple stressors on ecosystem services; and, vii) management of stressor effects should consider multiple occurrence scales. We discuss how to incorporate these aspects to present frameworks considering biophysical and societal consequences of multiple stressors, to better understand and manage the effects being caused on river networks.
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Affiliation(s)
- Sergi Sabater
- Catalan Institute for Water Research (ICRA), Girona, Spain; Institute of Aquatic Ecology, Universitat de Girona (UdG), Girona, Spain.
| | - Arturo Elosegi
- University of the Basque Country (UPV/EHU), Bilbao, Spain
| | - Ralf Ludwig
- Ludwig Maximilians Universitaet Muenchen (LMU), Munich, Germany
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9
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Pereda O, von Schiller D, García-Baquero G, Mor JR, Acuña V, Sabater S, Elosegi A. Combined effects of urban pollution and hydrological stress on ecosystem functions of Mediterranean streams. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 753:141971. [PMID: 33207454 DOI: 10.1016/j.scitotenv.2020.141971] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Revised: 08/10/2020] [Accepted: 08/23/2020] [Indexed: 06/11/2023]
Abstract
Urban pollution and hydrological stress are common stressors of stream ecosystems, but their combined effects on ecosystem functioning are still unclear. We measured a set of functional processes and accompanying environmental variables in locations upstream and downstream of urban sewage inputs in 13 streams covering a wide range of water pollution levels and hydrological variability. Sewage inputs seriously impaired stream chemical characteristics and led to complex effects on ecosystem functioning. Biofilm biomass accrual, whole-reach nutrient uptake and metabolism (ecosystem respiration) were generally subsidized, whereas organic matter decomposition and biofilm phosphorus uptake capacity decreased with increasing pollutant concentrations. Hydrological stress affected stream ecosystem functioning but its effect was minor compared to the effects of urban pollution, due to the large inter-site variability of the streams. Changes appeared mainly linked to the concentration of pharmaceutically active compounds, followed by other chemical characteristics and by hydrology. The results point to the need to further improve sewage treatment, especially as climate change will stress riverine organisms and reduce the dilution capacity of the receiving streams.
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Affiliation(s)
- Olatz Pereda
- Faculty of Science and Technology, the University of the Basque Country (UPV/EHU), PO Box 644, 48080 Bilbao, Spain.
| | - Daniel von Schiller
- Faculty of Science and Technology, the University of the Basque Country (UPV/EHU), PO Box 644, 48080 Bilbao, Spain; Department of Evolutionary Biology, Ecology and Environmental Sciences, Faculty of Biology, University of Barcelona (UB), 08028 Barcelona, Spain
| | - Gonzalo García-Baquero
- Faculty of Science and Technology, the University of the Basque Country (UPV/EHU), PO Box 644, 48080 Bilbao, Spain; Biodonostia Health Research Institute, Group of Environmental Epidemiology and Child Development, 20014 San Sebastian, Spain
| | - Jordi-René Mor
- Department of Evolutionary Biology, Ecology and Environmental Sciences, Faculty of Biology, University of Barcelona (UB), 08028 Barcelona, Spain; Catalan Institute for Water Research (ICRA), Carrer Emili Grahit 101, 17003 Girona, Spain; University of Girona (UdG), Plaça de Sant Domenec 3, 17004 Girona, Spain
| | - Vicenç Acuña
- Catalan Institute for Water Research (ICRA), Carrer Emili Grahit 101, 17003 Girona, Spain; University of Girona (UdG), Plaça de Sant Domenec 3, 17004 Girona, Spain
| | - Sergi Sabater
- Catalan Institute for Water Research (ICRA), Carrer Emili Grahit 101, 17003 Girona, Spain; Institute of Aquatic Ecology, Faculty of Science, University of Girona (UdG), Campus de Montilivi, 17003 Girona, Spain
| | - Arturo Elosegi
- Faculty of Science and Technology, the University of the Basque Country (UPV/EHU), PO Box 644, 48080 Bilbao, Spain
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10
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Silva DCVR, Queiroz LG, Marassi RJ, Araújo CVM, Bazzan T, Cardoso-Silva S, Silva GC, Müller M, Silva FT, Montagner CC, Paiva TCB, Pompêo MLM. Predicting zebrafish spatial avoidance triggered by discharges of dairy wastewater: An experimental approach based on self-purification in a model river. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 266:115325. [PMID: 32814178 DOI: 10.1016/j.envpol.2020.115325] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 07/08/2020] [Accepted: 07/27/2020] [Indexed: 06/11/2023]
Abstract
Wastewater discharges from dairy industries can cause a range of harmful effects in aquatic ecosystems, including a decline in biodiversity due to species evasion. Therefore, it is important to know the purification potential of rivers for the removal of pollutants released in dairy wastewater (DWW). The hypothesis adopted in this work was that the release of DWW into stretches of the Ribeirão dos Pombos River (São Paulo State, Brazil) might trigger an avoidance response, resulting in fish migrating to other regions, with the response being greater when the self-cleaning potential of the river is smaller. Therefore, the goals of the present study were to: (i) investigate how land use and seasonality of the rainfall regime influence the quality of the water in different areas of the river (P1: river source; P2: urban region; P3: rural region); (ii) assess the potential of the river to purify DWW; and (iii) evaluate the potential toxicity and repellency of DWW to the freshwater fish Danio rerio, using acute toxicity (mortality) and non-forced avoidance tests, respectively. P1 was shown to be the most preserved area. The chemical composition of the river varied seasonally, with higher concentrations of Cl- and SO42- at P3 during the rainy period. The river purification potential for DWW was higher at P2, due to greater microbiological activity (associated with higher BOD). The DWW was more acutely toxic in water from P2. The avoidance response was strongly determined by the concentration of DWW, especially for water from P2. The high capacity for self-cleaning at P2 did not seem sufficient to maintain the stability of the ecosystem. Finally, the non-forced exposure system proved to be a suitable approach that can assist in predicting how contaminants may affect the spatial distributions of organisms.
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Affiliation(s)
- Daniel C V R Silva
- Federal University of Southern and Southeastern Pará, Institute of Xingu Studies, São Félix Do Xingu, Pará, Brazil.
| | - Lucas G Queiroz
- Department of Biotechnology, Engineering School of Lorena, University of São Paulo, Lorena, São Paulo, Brazil
| | - Rodrigo J Marassi
- Department of Biotechnology, Engineering School of Lorena, University of São Paulo, Lorena, São Paulo, Brazil
| | - Cristiano V M Araújo
- Department of Ecology and Coastal Management, Institute of Marine Sciences of Andalusia (CSIC), Campus Río S. Pedro, 11510, Puerto Real, Cadiz, Spain
| | - Thiago Bazzan
- National Institute for Space Research, São José Dos Campos, São Paulo, Brazil
| | - Sheila Cardoso-Silva
- Program in Ecology and Natural Resource Management, UFAC, Rio Branco, AC, Brazil; Institute of Oceanography, University of São Paulo, São Paulo, Brazil
| | - Gilmar C Silva
- Postgraduate Program in Environmental Technology, Federal Fluminense University, Volta Redonda, Rio de Janeiro, Brazil
| | - M Müller
- Technological Institute of Aeronautics, São José Dos Campos, São Paulo, Brazil
| | - Flávio T Silva
- Department of Biotechnology, Engineering School of Lorena, University of São Paulo, Lorena, São Paulo, Brazil
| | - Cassiana C Montagner
- Department of Analytical Chemistry, Institute of Chemistry, Campinas State University, Campinas, São Paulo, Brazil
| | - Teresa C B Paiva
- Department of Biotechnology, Engineering School of Lorena, University of São Paulo, Lorena, São Paulo, Brazil
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11
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Burdon FJ, Bai Y, Reyes M, Tamminen M, Staudacher P, Mangold S, Singer H, Räsänen K, Joss A, Tiegs SD, Jokela J, Eggen RIL, Stamm C. Stream microbial communities and ecosystem functioning show complex responses to multiple stressors in wastewater. GLOBAL CHANGE BIOLOGY 2020; 26:6363-6382. [PMID: 32881210 PMCID: PMC7692915 DOI: 10.1111/gcb.15302] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 07/14/2020] [Accepted: 07/21/2020] [Indexed: 05/25/2023]
Abstract
Multiple anthropogenic drivers are changing ecosystems globally, with a disproportionate and intensifying impact on freshwater habitats. A major impact of urbanization are inputs from wastewater treatment plants (WWTPs). Initially designed to reduce eutrophication and improve water quality, WWTPs increasingly release a multitude of micropollutants (MPs; i.e., synthetic chemicals) and microbes (including antibiotic-resistant bacteria) to receiving environments. This pollution may have pervasive impacts on biodiversity and ecosystem services. Viewed through multiple lenses of macroecological and ecotoxicological theory, we combined field, flume, and laboratory experiments to determine the effects of wastewater (WW) on microbial communities and organic-matter processing using a standardized decomposition assay. First, we conducted a mensurative experiment sampling 60 locations above and below WWTP discharges in 20 Swiss streams. Microbial respiration and decomposition rates were positively influenced by WW inputs via warming and nutrient enrichment, but with a notable exception: WW decreased the activation energy of decomposition, indicating a "slowing" of this fundamental ecosystem process in response to temperature. Second, next-generation sequencing indicated that microbial community structure below WWTPs was altered, with significant compositional turnover, reduced richness, and evidence of negative MP influences. Third, a series of flume experiments confirmed that although diluted WW generally has positive influences on microbial-mediated processes, the negative effects of MPs are "masked" by nutrient enrichment. Finally, transplant experiments suggested that WW-borne microbes enhance decomposition rates. Taken together, our results affirm the multiple stressor paradigm by showing that different aspects of WW (warming, nutrients, microbes, and MPs) jointly influence ecosystem functioning in complex ways. Increased respiration rates below WWTPs potentially generate ecosystem "disservices" via greater carbon evasion from streams and rivers. However, toxic MP effects may fundamentally alter ecological scaling relationships, indicating the need for a rapprochement between ecotoxicological and macroecological perspectives.
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Affiliation(s)
- Francis J. Burdon
- EawagSwiss Federal Institute of Aquatic Science and TechnologyDübendorfSwitzerland
- Department of Aquatic Sciences and AssessmentSwedish University of Agricultural SciencesUppsalaSweden
| | - Yaohui Bai
- Research Center for Eco‐Environmental SciencesChinese Academy of SciencesBeijingPeople's Republic of China
| | - Marta Reyes
- EawagSwiss Federal Institute of Aquatic Science and TechnologyDübendorfSwitzerland
| | - Manu Tamminen
- EawagSwiss Federal Institute of Aquatic Science and TechnologyDübendorfSwitzerland
- Present address:
Department of BiologyUniversity of TurkuTurkuFinland
| | - Philipp Staudacher
- EawagSwiss Federal Institute of Aquatic Science and TechnologyDübendorfSwitzerland
| | - Simon Mangold
- EawagSwiss Federal Institute of Aquatic Science and TechnologyDübendorfSwitzerland
- Present address:
AgroscopeReckenholzstrasse 191Zurich8046Switzerland
| | - Heinz Singer
- EawagSwiss Federal Institute of Aquatic Science and TechnologyDübendorfSwitzerland
| | - Katja Räsänen
- EawagSwiss Federal Institute of Aquatic Science and TechnologyDübendorfSwitzerland
- Institute of Integrative BiologyETH ZürichZürichSwitzerland
| | - Adriano Joss
- EawagSwiss Federal Institute of Aquatic Science and TechnologyDübendorfSwitzerland
| | - Scott D. Tiegs
- Department of Biological SciencesOakland UniversityRochesterMIUSA
| | - Jukka Jokela
- EawagSwiss Federal Institute of Aquatic Science and TechnologyDübendorfSwitzerland
- Institute of Integrative BiologyETH ZürichZürichSwitzerland
| | - Rik I. L. Eggen
- EawagSwiss Federal Institute of Aquatic Science and TechnologyDübendorfSwitzerland
- Institute of Biogeochemistry and Pollutant DynamicsETH ZürichZürichSwitzerland
| | - Christian Stamm
- EawagSwiss Federal Institute of Aquatic Science and TechnologyDübendorfSwitzerland
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12
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Burdon FJ, Bai Y, Reyes M, Tamminen M, Staudacher P, Mangold S, Singer H, Räsänen K, Joss A, Tiegs SD, Jokela J, Eggen RIL, Stamm C. Stream microbial communities and ecosystem functioning show complex responses to multiple stressors in wastewater. GLOBAL CHANGE BIOLOGY 2020. [PMID: 32881210 DOI: 10.5061/dryad.z34tmpgb2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Multiple anthropogenic drivers are changing ecosystems globally, with a disproportionate and intensifying impact on freshwater habitats. A major impact of urbanization are inputs from wastewater treatment plants (WWTPs). Initially designed to reduce eutrophication and improve water quality, WWTPs increasingly release a multitude of micropollutants (MPs; i.e., synthetic chemicals) and microbes (including antibiotic-resistant bacteria) to receiving environments. This pollution may have pervasive impacts on biodiversity and ecosystem services. Viewed through multiple lenses of macroecological and ecotoxicological theory, we combined field, flume, and laboratory experiments to determine the effects of wastewater (WW) on microbial communities and organic-matter processing using a standardized decomposition assay. First, we conducted a mensurative experiment sampling 60 locations above and below WWTP discharges in 20 Swiss streams. Microbial respiration and decomposition rates were positively influenced by WW inputs via warming and nutrient enrichment, but with a notable exception: WW decreased the activation energy of decomposition, indicating a "slowing" of this fundamental ecosystem process in response to temperature. Second, next-generation sequencing indicated that microbial community structure below WWTPs was altered, with significant compositional turnover, reduced richness, and evidence of negative MP influences. Third, a series of flume experiments confirmed that although diluted WW generally has positive influences on microbial-mediated processes, the negative effects of MPs are "masked" by nutrient enrichment. Finally, transplant experiments suggested that WW-borne microbes enhance decomposition rates. Taken together, our results affirm the multiple stressor paradigm by showing that different aspects of WW (warming, nutrients, microbes, and MPs) jointly influence ecosystem functioning in complex ways. Increased respiration rates below WWTPs potentially generate ecosystem "disservices" via greater carbon evasion from streams and rivers. However, toxic MP effects may fundamentally alter ecological scaling relationships, indicating the need for a rapprochement between ecotoxicological and macroecological perspectives.
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Affiliation(s)
- Francis J Burdon
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
- Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Yaohui Bai
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, People's Republic of China
| | - Marta Reyes
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
| | - Manu Tamminen
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
| | - Philipp Staudacher
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
| | - Simon Mangold
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
| | - Heinz Singer
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
| | - Katja Räsänen
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
- Institute of Integrative Biology, ETH Zürich, Zürich, Switzerland
| | - Adriano Joss
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
| | - Scott D Tiegs
- Department of Biological Sciences, Oakland University, Rochester, MI, USA
| | - Jukka Jokela
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
- Institute of Integrative Biology, ETH Zürich, Zürich, Switzerland
| | - Rik I L Eggen
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
- Institute of Biogeochemistry and Pollutant Dynamics, ETH Zürich, Zürich, Switzerland
| | - Christian Stamm
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
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13
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Pereda O, Solagaistua L, Atristain M, de Guzmán I, Larrañaga A, von Schiller D, Elosegi A. Impact of wastewater effluent pollution on stream functioning: A whole-ecosystem manipulation experiment. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 258:113719. [PMID: 31838390 DOI: 10.1016/j.envpol.2019.113719] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Revised: 11/02/2019] [Accepted: 12/01/2019] [Indexed: 06/10/2023]
Abstract
The ecological effects of wastewater treatment plant (WWTP) effluents on stream ecosystems cause growing concern. However, it is difficult to assess these effects as most streams receiving WWTP effluents are also affected by other stressors. We performed a whole-ecosystem manipulation experiment following a BACI design (Before-After/Control-Impact) in order to exclude the influence of other potentially confounding factors. We diverted part of the effluent of a large tertiary urban WWTP into a small, unpolluted stream, and studied its effects on ecosystem structure and functioning over two years (i.e., one year before and one year after the effluent diversion). Although highly diluted (final concentration in the receiving stream averaged 3%), the effluent promoted biofilm chlorophyll-a and biomass (2.3 and 2.1 times, respectively), exo-enzymatic activities (phosphatase 2.2 and glucosidase 4.2 times) and invertebrate-mediated organic matter decomposition (1.4 times), but reduced phosphorus uptake capacity of the epilithic biofilm down to 0.5 of the initial values. Biofilm metabolism, reach-scale nutrient uptake and microbially-mediated organic matter decomposition were not affected. Our results indicate that even well treated and highly diluted WWTP effluents can also affect the structure of the biofilm community and stream ecosystem functioning.
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Affiliation(s)
- Olatz Pereda
- Faculty of Science and Technology, The University of the Basque Country (UPV/EHU), PO Box 644, 48080, Bilbao, Spain.
| | - Libe Solagaistua
- Faculty of Science and Technology, The University of the Basque Country (UPV/EHU), PO Box 644, 48080, Bilbao, Spain
| | - Miren Atristain
- Faculty of Science and Technology, The University of the Basque Country (UPV/EHU), PO Box 644, 48080, Bilbao, Spain
| | - Ioar de Guzmán
- Faculty of Science and Technology, The University of the Basque Country (UPV/EHU), PO Box 644, 48080, Bilbao, Spain
| | - Aitor Larrañaga
- Faculty of Science and Technology, The University of the Basque Country (UPV/EHU), PO Box 644, 48080, Bilbao, Spain
| | - Daniel von Schiller
- Faculty of Science and Technology, The University of the Basque Country (UPV/EHU), PO Box 644, 48080, Bilbao, Spain
| | - Arturo Elosegi
- Faculty of Science and Technology, The University of the Basque Country (UPV/EHU), PO Box 644, 48080, Bilbao, Spain
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14
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de Santiago-Martín A, Meffe R, Teijón G, Martínez Hernández V, López-Heras I, Alonso Alonso C, Arenas Romasanta M, de Bustamante I. Pharmaceuticals and trace metals in the surface water used for crop irrigation: Risk to health or natural attenuation? THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 705:135825. [PMID: 31818606 DOI: 10.1016/j.scitotenv.2019.135825] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 11/26/2019] [Accepted: 11/26/2019] [Indexed: 06/10/2023]
Abstract
The use of surface water impacted by wastewater treatment plant (WWTP) effluents for crop irrigation is a form of unplanned water reuse. Natural attenuation processes can buffer contamination spreading. However, this practice can promote the exposure of crops to contaminants of emerging concern, such as pharmaceuticals, trace metals (TMs) and metalloids, posing a risk to health. This research aimed to evaluate the presence of 50 pharmaceuticals, some transformation products, 7 TMs and a metalloid in the water-sediment-soil-plant system, and their potential to be bioaccumulated into edible parts of plants, as a result of the unplanned water reuse. The study site consists of an extensive agricultural land downstream Madrid city (Spain) where surface water, strongly impacted by WWTP effluents, is applied through gravity-based systems to cultivate mainly maize. Sampling campaigns were conducted to collect WWTP effluent, surface and irrigation water, river sediments, agricultural soils and maize fruits. Results demonstrate the ubiquitous presence of several pharmaceuticals. The concentration pattern in irrigation water did not resemble the pattern of contents in soils and plants. The pharmaceuticals included in the EU surface water watch lists were quantified in the lowest concentration range (macrolide antibiotics, ciprofloxacin) or were not detected (most of the hormones). Therefore, hormones do not represent an emerging risk in our scenario. The TMs and the metalloid in water and agricultural soils should not arise any concern. Whereas, their presence in the river sediments may have an adverse impact on aquatic ecosystems. Only acetaminophen, ibuprofen, carbamazepine, nicotine, Zn, Cu and Ni were quantified in corn grains. Calculated parameters to assess bioaccumulation and health risk indicate that neither pharmaceuticals nor TMs pose a threat to human health due to consumption of maize cultivated in the area. Results highlight the need to include different environmental matrices when assessing contaminant fate under real field-scale conditions.
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Affiliation(s)
| | - Raffaella Meffe
- IMDEA Water, Avda. Punto Com, 2, 28805 Alcalá de Henares, Madrid, Spain
| | - Gloria Teijón
- IMDEA Water, Avda. Punto Com, 2, 28805 Alcalá de Henares, Madrid, Spain
| | | | | | | | | | - Irene de Bustamante
- IMDEA Water, Avda. Punto Com, 2, 28805 Alcalá de Henares, Madrid, Spain; University of Alcalá, Geology, Geography and Environment Department, Faculty of Sciences, External Campus, Ctra. A-II km 33.6, 28871 Alcalá de Henares, Madrid, Spain
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15
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Romero F, Acuña V, Font C, Freixa A, Sabater S. Effects of multiple stressors on river biofilms depend on the time scale. Sci Rep 2019; 9:15810. [PMID: 31676856 PMCID: PMC6825187 DOI: 10.1038/s41598-019-52320-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Accepted: 10/15/2019] [Indexed: 11/08/2022] Open
Abstract
Global change exposes ecosystems to a myriad of stressors differing in their spatial (i.e. surface of stressed area) and temporal (i.e. exposure time) components. Among freshwater ecosystems, rivers and streams are subject to physical, chemical and biological stressors, which interact with each other and might produce diverging effects depending on exposure time. We conducted a manipulative experiment using 24 artificial streams to examine the individual and combined effects of warming (1.6 °C increase in water temperature), hydrological stress (simulated low-flow situation) and chemical stress caused by pesticide exposure (15.1-156.7 ng L-1) on river biofilms. We examined whether co-occurring stressors could lead to non-additive effects, and if these differed at two different exposure times. Specifically, structural and functional biofilm responses were assessed after 48 hours (short-term effects) and after 30 days (long-term effects) of exposure. Hydrological stress caused strong negative impacts on river biofilms, whereas effects of warming and pesticide exposure were less intense, although increasing on the long term. Most stressor combinations (71%) resulted in non-significant interactions, suggesting overall additive effects, but some non-additive interactions also occurred. Among non-additive interactions, 59% were classified as antagonisms after short-term exposure to the different stressor combinations, rising to 86% at long term. Our results indicate that a 30-day exposure period to multiple stressors increases the frequency of antagonistic interactions compared to a 48-hour exposure to the same conditions. Overall, the impacts of multiple-stressor occurrences appear to be hardly predictable from individual effects, highlighting the need to consider temporal components such as duration when predicting the effects of multiple stressors.
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Affiliation(s)
- Ferran Romero
- Catalan Institute for Water Research (ICRA), C. Emili Grahit 101, 17003, Girona, Spain.
- Universitat de Girona (UdG), Girona, Spain.
| | - Vicenç Acuña
- Catalan Institute for Water Research (ICRA), C. Emili Grahit 101, 17003, Girona, Spain
- Universitat de Girona (UdG), Girona, Spain
| | - Carme Font
- Catalan Institute for Water Research (ICRA), C. Emili Grahit 101, 17003, Girona, Spain
- Universitat de Girona (UdG), Girona, Spain
| | - Anna Freixa
- Catalan Institute for Water Research (ICRA), C. Emili Grahit 101, 17003, Girona, Spain
- Universitat de Girona (UdG), Girona, Spain
| | - Sergi Sabater
- Catalan Institute for Water Research (ICRA), C. Emili Grahit 101, 17003, Girona, Spain
- Institute of Aquatic Ecology (IEA), University of Girona, Campus de Montilivi, 17003, Girona, Spain
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16
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Pu Y, Ngan WY, Yao Y, Habimana O. Could benthic biofilm analyses be used as a reliable proxy for freshwater environmental health? ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2019; 252:440-449. [PMID: 31158672 DOI: 10.1016/j.envpol.2019.05.111] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Revised: 05/21/2019] [Accepted: 05/21/2019] [Indexed: 05/22/2023]
Abstract
The quality of freshwater undoubtedly reflects the health of our surrounding environment, society, and economy, as these are supported by various freshwater ecosystems. Monitoring efforts have therefore been considered a vital means of ensuring the ecological health of freshwater environments. Nevertheless, most aquatic environmental monitoring strategies largely focus on bulk water sampling for analysis of physicochemical and key biological indicators, which for the most part do not consider pollution events that occur at any time between sampling events. Because benthic biofilms are ubiquitous in aquatic environments, pollution released during sporadic events may be absorbed by these biofilms, which can act as repositories of pollutants. The aim of this study was to assess whether benthic biofilm monitoring could provide an efficient way of properly characterizing the extent of pollution in aquatic environments. Here, bulk water and benthic biofilms were sampled from three Hong Kong streams having various pollution profiles, and subsequently compared via high-resolution microscopy, metagenomic analysis, and analytical chemistry. The results indicated that biofilms were, indeed, reservoirs of environmental pollutants, having different profiles compared with that of the corresponding bulk water samples. Moreover, the results also suggested that biofilms sampled in polluted areas were characterized by a higher species richness. While the analytical testing of benthic biofilms still needs further development, the integration of chemical-pollutant profiles and biofilm sequencing data in future studies may provide unique perspectives for understanding and identifying pollution-related biofilm biomarkers.
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Affiliation(s)
- Yang Pu
- School of Biological Sciences, Faculty of Science, The University of Hong Kong, Pokfulam, Hong Kong Special Administration Region
| | - Wing Yui Ngan
- School of Biological Sciences, Faculty of Science, The University of Hong Kong, Pokfulam, Hong Kong Special Administration Region
| | - Yuan Yao
- School of Biological Sciences, Faculty of Science, The University of Hong Kong, Pokfulam, Hong Kong Special Administration Region
| | - Olivier Habimana
- School of Biological Sciences, Faculty of Science, The University of Hong Kong, Pokfulam, Hong Kong Special Administration Region; The University of Hong Kong-Shenzhen Institute of Research and Innovation (HKU-SIRI), Shenzhen, Guangdong Province, People's Republic of China.
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