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Klátyik S, Takács E, Barócsi A, Lenk S, Kocsányi L, Darvas B, Székács A. Hormesis, the Individual and Combined Phytotoxicity of the Components of Glyphosate-Based Formulations on Algal Growth and Photosynthetic Activity. TOXICS 2024; 12:257. [PMID: 38668480 PMCID: PMC11055126 DOI: 10.3390/toxics12040257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2024] [Revised: 03/22/2024] [Accepted: 03/27/2024] [Indexed: 04/29/2024]
Abstract
The occurrence of the market-leading glyphosate active ingredient in surface waters is a globally observed phenomenon. Although co-formulants in pesticide formulations were considered inactive components from the aspects of the required main biological effect of the pesticide, several studies have proven the high individual toxicity of formulating agents, as well as the enhanced combined toxicity of the active ingredients and other components. Since the majority of active ingredients are present in the form of chemical mixtures in our environment, the possible combined toxicity between active ingredients and co-formulants is particularly important. To assess the individual and combined phytotoxicity of the components, glyphosate was tested in the form of pure active ingredient (glyphosate isopropylammonium salt) and herbicide formulations (Roundup Classic and Medallon Premium) formulated with a mixture of polyethoxylated tallow amines (POEA) or alkyl polyglucosides (APG), respectively. The order of acute toxicity was as follows for Roundup Classic: glyphosate < herbicide formulation < POEA. However, the following order was demonstrated for Medallon Premium: herbicide formulation < glyphosate < APG. Increased photosynthetic activity was detected after the exposure to the formulation (1.5-5.8 mg glyphosate/L and 0.5-2.2 mg POEA/L) and its components individually (glyphosate: 13-27.2 mg/L, POEA: 0.6-4.8 mg/L), which indicates hormetic effects. However, decreased photosynthetic activity was detected at higher concentrations of POEA (19.2 mg/L) and Roundup Classic (11.6-50.6 mg glyphosate/L). Differences were demonstrated in the sensitivity of the selected algae species and, in addition to the individual and combined toxicity of the components presented in the glyphosate-based herbicides. Both of the observed inhibitory and stimulating effects can adversely affect the aquatic ecosystems and water quality of surface waters.
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Affiliation(s)
- Szandra Klátyik
- Agro-Environmental Research Centre, Institute of Environmental Sciences, Hungarian University of Agriculture and Life Sciences, H-2100 Gödöllő, Hungary; (S.K.); (E.T.)
| | - Eszter Takács
- Agro-Environmental Research Centre, Institute of Environmental Sciences, Hungarian University of Agriculture and Life Sciences, H-2100 Gödöllő, Hungary; (S.K.); (E.T.)
| | - Attila Barócsi
- Department of Atomic Physics, Institute of Physics, Budapest University of Technology and Economics, H-1111 Budapest, Hungary; (A.B.); (S.L.); (L.K.)
| | - Sándor Lenk
- Department of Atomic Physics, Institute of Physics, Budapest University of Technology and Economics, H-1111 Budapest, Hungary; (A.B.); (S.L.); (L.K.)
| | - László Kocsányi
- Department of Atomic Physics, Institute of Physics, Budapest University of Technology and Economics, H-1111 Budapest, Hungary; (A.B.); (S.L.); (L.K.)
| | - Béla Darvas
- Hungarian Society of Ecotoxicology, H-1022 Budapest, Hungary;
| | - András Székács
- Agro-Environmental Research Centre, Institute of Environmental Sciences, Hungarian University of Agriculture and Life Sciences, H-2100 Gödöllő, Hungary; (S.K.); (E.T.)
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Bodean MF, Regaldo L, Mayora G, Mora C, Giri F, Gervasio S, Popielarz A, Repetti MR, Licursi M. Effects of herbicides and fertilization on biofilms of Pampean lotic systems: A microcosm study. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 917:170238. [PMID: 38280601 DOI: 10.1016/j.scitotenv.2024.170238] [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: 09/13/2023] [Revised: 12/02/2023] [Accepted: 01/15/2024] [Indexed: 01/29/2024]
Abstract
We experimentally assessed the impact of the application of herbicides and fertilizers derived from agricultural activity through the individual and simultaneous addition of glyphosate, atrazine, and nutrients (nitrogen 'N' and phosphorus 'P') on the biofilm community and their resilience when the experimental factors were removed. We hypothesize that i) the presence of agrochemicals negatively affects the biofilm community leading to the simplification of the community structure; ii) the individual or simultaneous addition of herbicides and nutrients produces differential responses in the biofilm; and iii) the degree of biofilm recovery differs according to the treatment applied. Environmentally relevant concentrations of glyphosate (0.7 mgL-1), atrazine (44 μgL-1), phosphorus (1 mg P L-1 [KH2PO4]), and nitrogen (3 mg N L-1[NaNO3]) were used. Chlorophyll a, ash-free dry weight, abundance of main biofilm groups and nutrient contents in biofilm were analyzed. At initial exposure time, all treatments were dominated by Cyanobacteria; through the exposure period, it was observed a progressive replacement by Bacillariophyceae. This replacement occurred on day 3 for the control and was differentially delayed in all herbicides and/or nutrient treatments in which the abundance of cyanobacteria remains significant yet in T5. A significant correlation was observed between the abundance of cyanobacteria and the concentration of atrazine, suggesting that this group is less sensitive than diatoms. The presence of agrochemicals exerted differential effects on the different algal groups. Herbicides contributed to phosphorus and nitrogen inputs. The most frequently observed interactions between experimental factors (nutrients and herbicides) was additivity excepting for species richness (antagonistic effect). In the final recovery time, no significant differences were found between the treatments and the control in most of the evaluated parameters, evincing the resilience of the community.
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Affiliation(s)
- María Florencia Bodean
- Instituto Nacional de Limnología 'INALI', Consejo Nacional de Investigaciones Científicas y Técnicas - Universidad Nacional del Litoral (CONICET-UNL), Ciudad Universitaria, Santa Fe, Argentina
| | - Luciana Regaldo
- Facultad de Humanidades y Ciencias (FHUC, UNL-CONICET), Ciudad Universitaria, Santa Fe, Argentina
| | - Gisela Mayora
- Instituto Nacional de Limnología 'INALI', Consejo Nacional de Investigaciones Científicas y Técnicas - Universidad Nacional del Litoral (CONICET-UNL), Ciudad Universitaria, Santa Fe, Argentina
| | - Celeste Mora
- Instituto Nacional de Limnología 'INALI', Consejo Nacional de Investigaciones Científicas y Técnicas - Universidad Nacional del Litoral (CONICET-UNL), Ciudad Universitaria, Santa Fe, Argentina
| | - Federico Giri
- Instituto Nacional de Limnología 'INALI', Consejo Nacional de Investigaciones Científicas y Técnicas - Universidad Nacional del Litoral (CONICET-UNL), Ciudad Universitaria, Santa Fe, Argentina; Facultad de Humanidades y Ciencias (FHUC, UNL-CONICET), Ciudad Universitaria, Santa Fe, Argentina
| | - Susana Gervasio
- Instituto Nacional de Tecnología (INTEC, CONICET - UNL), Parque Tecnológico Litoral Centro, Santa Fe, Argentina
| | - Andrea Popielarz
- Instituto Nacional de Tecnología (INTEC, CONICET - UNL), Parque Tecnológico Litoral Centro, Santa Fe, Argentina
| | | | - Magdalena Licursi
- Instituto Nacional de Limnología 'INALI', Consejo Nacional de Investigaciones Científicas y Técnicas - Universidad Nacional del Litoral (CONICET-UNL), Ciudad Universitaria, Santa Fe, Argentina.
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Morin S, Artigas J. Twenty Years of Research in Ecosystem Functions in Aquatic Microbial Ecotoxicology. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2023; 42:1867-1888. [PMID: 37401851 DOI: 10.1002/etc.5708] [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: 11/29/2022] [Revised: 12/20/2022] [Accepted: 06/27/2023] [Indexed: 07/05/2023]
Abstract
One of the major threats to freshwater biodiversity is water pollution including excessive loads of nutrients, pesticides, industrial chemicals, and/or emerging contaminants. The widespread use of organic pesticides for agricultural and nonagricultural (industry, gardening, etc.) purposes has resulted in the presence of their residues in various environments, including surface waters. However, the contribution of pesticides to the deterioration of freshwater ecosystems (i.e., biodiversity decline and ecosystem functions impairment) remains uncertain. Once in the aquatic environment, pesticides and their metabolites can interact with microbial communities, causing undesirable effects. The existing legislation on ecological quality assessment of water bodies in Europe is based on water chemical quality and biological indicator species (Water Framework Directive, Pesticides Directive), while biological functions are not yet included in monitoring programs. In the present literature review, we analyze 20 years (2000-2020) of research on ecological functions provided by microorganisms in aquatic ecosystems. We describe the set of ecosystem functions investigated in these studies and the range of endpoints used to establish causal relationships between pesticide exposure and microbial responses. We focus on studies addressing the effects of pesticides at environmentally realistic concentrations and at the microbial community level to inform the ecological relevance of the ecotoxicological assessment. Our literature review highlights that most studies were performed using benthic freshwater organisms and that autotrophic and heterotrophic communities are most often studied separately, usually testing the pesticides that target the main microbial component (i.e., herbicides for autotrophs and fungicides for heterotrophs). Overall, most studies demonstrate deleterious impacts on the functions studied, but our review points to the following shortcomings: (1) the nonsystematic analysis of microbial functions supporting aquatic ecosystems functioning, (2) the study of ecosystem functions (i.e., nutrient cycling) via proxies (i.e., potential extracellular enzymatic activity measurements) which are sometimes disconnected from the current ecosystem functions, and (3) the lack of consideration of chronic exposures to assess the impact of, adaptations to, or recovery of aquatic microbial communities from pesticides. Environ Toxicol Chem 2023;42:1867-1888. © 2023 SETAC.
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Affiliation(s)
| | - Joan Artigas
- Laboratoire Microorganismes: Génome et Environnement, CNRS, Université Clermont Auvergne, Clermont-Ferrand, France
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Lima IB, Boëchat IG, Fernandes MD, Monteiro JAF, Rivaroli L, Gücker B. Glyphosate pollution of surface runoff, stream water, and drinking water resources in Southeast Brazil. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:27030-27040. [PMID: 36376647 DOI: 10.1007/s11356-022-24167-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Accepted: 11/08/2022] [Indexed: 06/16/2023]
Abstract
Glyphosate-based herbicides can be harmful to the environment and human health. Especially in developing countries, these herbicides are often used indiscriminately in agricultural and urban areas. Here, we optimized a simple and efficient flow injection-based spectrophotometric method to monitor environmentally relevant glyphosate concentrations in surface waters. The method was then used to assess the environmental mobility of glyphosate in Southeast Brazil by monitoring surface runoff from experimental agricultural soil plots that received glyphosate applications in 2015. Further, water samples from low-order streams were collected in five agricultural, urban, and natural areas, as well as from the 5th-order Rio das Mortes during the rainy season. Finally, 20 drinking water sources were sampled in urban, rural, and agricultural areas. Runoff from reference plots without glyphosate application showed concentrations below the method's detection limit of 0.49 mg.L-1, whereas runoff from plots with standard glyphosate application had concentrations between 1.24 and 6.1 mg.L-1. Similarly, concentrations in natural stream water were below the detection limit, whereas agricultural streams had concentrations of up to 3.7 mg.L-1 (average: 0.97 mg.L-1). In an agricultural stream monitored weekly, concentration peaks were observed after glyphosate applications by farmers, and concentrations were correlated to stream discharge. Urban streams had concentrations of up to 5.8 mg.L-1 (average: 2.6 mg.L-1), but samples from the catchment's major river were mostly below detection limits, illustrating the dilution of urban and agricultural runoff in high-order rivers. In the sampled drinking water resources, glyphosate pollution occurred mainly in the rainy season, with detectable concentrations between 0.5 and 8.7 mg.L-1 in 80% of the sampled drinking water sources. In conclusion, our results suggest considerable environmental mobility of glyphosate in the studied Southeast Brazilian catchment. Substantial pollution, well above national and international limits, was detected in surface runoff, stream water, and drinking water resources.
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Affiliation(s)
- Igor B Lima
- Department of Geosciences, Federal University of São João del-Rei, São João del-Rei, MG, Brazil
| | - Iola G Boëchat
- Department of Geosciences, Federal University of São João del-Rei, São João del-Rei, MG, Brazil
| | - Marco D Fernandes
- Department of Geosciences, Federal University of São João del-Rei, São João del-Rei, MG, Brazil
| | | | - Luciano Rivaroli
- Department of Natural Sciences, Federal University of São João del-Rei, São João del-Rei, MG, Brazil
| | - Björn Gücker
- Department of Geosciences, Federal University of São João del-Rei, São João del-Rei, MG, Brazil.
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Freixa A, Ortiz-Rivero J, Sabater S. Artificial substrata to assess ecological and ecotoxicological responses in river biofilms: Use and recommendations. MethodsX 2023; 10:102089. [PMID: 36915862 PMCID: PMC10006700 DOI: 10.1016/j.mex.2023.102089] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Accepted: 02/20/2023] [Indexed: 02/24/2023] Open
Abstract
River biofilms are biological consortia of autotrophs and heterotrophs colonizing most solid surfaces in rivers. Biofilm composition and biomass differ according to the environmental conditions, having different characteristics between systems and even between river habitats. Artificial substrata (AS) are an alternative for in situ or laboratory experiments to handle the natural variability of biofilms. However, specific research goals may require decisions on colonization time or type of substrata. Substrata properties (i.e., texture, roughness, hydrophobicity) and the colonization period and site are selective factors of biofilm characteristics. Here we describe the uses of artificial substrata in the assessment of ecological and ecotoxicological responses and propose a decision tree for the best use of artificial substrata in river biofilm studies. We propose departing from the purpose of the study to define the necessity of obtaining a realistic biofilm community, from which it may be defined the colonization time, the colonization site, and the type of artificial substratum. Having a simple or mature biofilm community should guide our decisions on the colonization time and type of substrata to be selected for the best use of AS in biofilm studies. Tests involving contaminants should avoid adsorbing materials while those ecologically oriented may use any AS mimicking those substrata occurring in the streambed.•We review the utilization of different artificial substrata to colonize biofilm in river ecology and ecotoxicology.•We propose a decision tree to guide on selecting the appropriate artificial substrata and colonization site and duration.•Type of artificial substrata (material, size, shape...) and colonization duration are to be decided according to the specific purpose of the study.
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Affiliation(s)
- Anna Freixa
- Catalan Institute for Water Research (ICRA-CERCA), Carrer Emili Grahit 101, 17003 Girona, Spain.,University of Girona, Plaça de Sant Domènec 3, 17004, Girona, Spain
| | - Javier Ortiz-Rivero
- Catalan Institute for Water Research (ICRA-CERCA), Carrer Emili Grahit 101, 17003 Girona, Spain.,University of Girona, Plaça de Sant Domènec 3, 17004, Girona, Spain
| | - Sergi Sabater
- Catalan Institute for Water Research (ICRA-CERCA), Carrer Emili Grahit 101, 17003 Girona, Spain.,Institute of Aquatic Ecology, University of Girona, Campus de Montilivi, 17071 Girona, Spain
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Agathokleous E, Barceló D, Rinklebe J, Sonne C, Calabrese EJ, Koike T. Hormesis induced by silver iodide, hydrocarbons, microplastics, pesticides, and pharmaceuticals: Implications for agroforestry ecosystems health. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 820:153116. [PMID: 35063521 DOI: 10.1016/j.scitotenv.2022.153116] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 01/10/2022] [Accepted: 01/10/2022] [Indexed: 06/14/2023]
Abstract
Increasing amounts of silver iodide (AgI) in the environment are expected because of the recent massive expansion of weather modification programs. Concurrently, pharmaceuticals, microplastics, hydrocarbons, and pesticides in terrestrial ecosystems continue contaminating forests and agroforests. Our review supports that AgI induces hormesis, a biphasic dose response characterized by often beneficial low-dose responses and toxic high-dose effects, which adds to the evidence for pharmaceuticals, microplastics, hydrocarbons, and pesticides induced hormesis in numerous species. Doses smaller than the no-observed-adverse-effect-level (NOAEL) positively affect defense physiology, growth, biomass, yields, survival, lifespan, and reproduction. They also lead to negative or undesirable outcomes, including stimulation of pathogenic microbes, pest insects, and weeds with enhanced resistance to drugs and potential negative multi- or trans-generational effects. Such sub-NOAEL effects perplex terrestrial ecosystems managements and may compromise combating outbreaks of disease vectors that can threaten not only forest and agroforestry health but also sensitive human subpopulations living in remote forested areas.
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Affiliation(s)
- Evgenios Agathokleous
- School of Applied Meteorology, Nanjing University of Information Science and Technology (NUIST), Ningliu Rd. 219, Nanjing, Jiangsu 210044, China.
| | - Damià Barceló
- Institute of Environmental Assessment and Water Research, IDAEA-CSIC, C/ Jordi Girona 18-26, 08034 Barcelona, Spain; Catalan Institute for Water Research, ICRA-CERCA, Emili Grahit 101, 17003 Girona, Spain
| | - Jörg Rinklebe
- University of Wuppertal, School of Architecture and Civil Engineering, Institute of Foundation Engineering, Water- and Waste-Management, Laboratory of Soil- and Groundwater-Management, Wuppertal, Germany; Department of Environment, Energy and Geoinformatics, Sejong University, Seoul, Republic of Korea
| | - Christian Sonne
- Department of Bioscience, Aarhus University, Arctic Research Center (ARC), Frederiksborgvej 399, PO box 358, DK-4000 Roskilde, Denmark; Henan Province Engineering Research Center for Biomass Value-added Products, School of Forestry, Henan Agricultural University, Zhengzhou 450002, China
| | - Edward J Calabrese
- Department of Environmental Health Sciences, Morrill I, N344, University of Massachusetts, Amherst, MA 01003, USA
| | - Takayoshi Koike
- Research Faculty of Agriculture, Hokkaido University, Sapporo 060-8589, Hokkaido, Japan
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Zabaloy MC, Allegrini M, Hernandez Guijarro K, Behrends Kraemer F, Morrás H, Erijman L. Microbiomes and glyphosate biodegradation in edaphic and aquatic environments: recent issues and trends. World J Microbiol Biotechnol 2022; 38:98. [PMID: 35478266 DOI: 10.1007/s11274-022-03281-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Accepted: 04/08/2022] [Indexed: 12/11/2022]
Abstract
Glyphosate (N-(phosphonomethyl)glycine) has emerged as the top-selling herbicide worldwide because of its versatility in controlling annual and perennial weeds and the extensive use of glyphosate-resistant crops. Concerns related to the widespread use of glyphosate and its ubiquitous presence in the environment has led to a large number of studies and reviews, which examined the toxicity and fate of glyphosate and its major metabolite, aminomethylphosphonic acid (AMPA) in the environment. Because the biological breakdown of glyphosate is most likely the main elimination process, the biodegradation of glyphosate has also been the object of abundant experimental work. Importantly, glyphosate biodegradation in aquatic and soil ecosystems is affected not only by the composition and the activity of microbial communities, but also by the physical environment. However, the interplay between microbiomes and glyphosate biodegradation in edaphic and aquatic environments has rarely been considered before. The proposed minireview aims at filling this gap. We summarize the most recent work exploring glyphosate biodegradation in natural aquatic biofilms, the biological, chemical and physical factors and processes playing on the adsorption, transport and biodegradation of glyphosate at different levels of soil organization and under different agricultural managements, and its impact on soil microbial communities.
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Affiliation(s)
- María Celina Zabaloy
- Centro de Recursos Naturales Renovables de la Zona Semiárida (CERZOS), Universidad Nacional del Sur (UNS)-CONICET, Bahía Blanca, Argentina
- Departamento de Agronomía, Universidad Nacional del Sur, Bahía Blanca, Argentina
| | - Marco Allegrini
- Instituto de Investigaciones en Ciencias Agrarias de Rosario (IICAR), CONICET, Universidad Nacional de Rosario, Zavalla, Argentina
| | - Keren Hernandez Guijarro
- Instituto Nacional de Tecnología Agropecuaria (INTA), Unidad Integrada Estación Experimental Agropecuaria Balcarce, Balcarce, Argentina
| | - Filipe Behrends Kraemer
- Cátedra de Manejo y Conservación de Suelos, Facultad de Agronomía, Universidad de Buenos Aires, Buenos Aires, Argentina
- Instituto de Suelos-CIRN-INTA, Hurlingham, Argentina
| | - Héctor Morrás
- Instituto de Suelos-CIRN-INTA, Hurlingham, Argentina
- Facultad de Ciencias Agrarias y Veterinaria, Universidad del Salvador, Pilar, Argentina
| | - Leonardo Erijman
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr Héctor N. Torres" (INGEBI-CONICET), Vuelta de Obligado 2490, C1428ADN, Buenos Aires, Argentina.
- Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina.
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Wang Z, Yin S, Chou Q, Zhou D, Jeppesen E, Wang L, Zhang W. Community-level and function response of photoautotrophic periphyton exposed to oxytetracycline hydrochloride. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 294:118593. [PMID: 34864100 DOI: 10.1016/j.envpol.2021.118593] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 11/17/2021] [Accepted: 11/25/2021] [Indexed: 06/13/2023]
Abstract
Periphyton is considered important for removal of organic pollutants from water bodies, but knowledge of the impacts of antibiotics on the community structure and ecological function of waterbodies remains limited. In this study, the effects of oxytetracycline hydrochloride (OTC) on the communities of photoautotrophic epilithon and epipelon and its effect on nitrogen and phosphorus concentrations in the water column were studied in a 12-day mesocosm experiment. The dynamics of nitrogen and phosphorus concentrations in the epipelon and epilithon experiment showed similar patterns. The concentrations of total nitrogen, dissolved total nitrogen, ammonium nitrogen, total phosphorus and dissolved total phosphorus in the water column increased rapidly during the initial days of exposure, after which a downward trend occurred. In the epilithon experiment, we found that the photosynthesis (Fv/Fm) and biomass of epilithon were significantly (P < 0.05) stimulated in the low concentration group. Contrarily, growth and photosynthesis (Fv/Fm) were significantly (P < 0.05) reduced in the medium and high concentration group. We further found that the photosynthetic efficiency of photoautotrophic epilithon was negatively correlated with the concentrations of nitrogen and phosphorus in the water column (P < 0.05). Principal coordinate analysis (PCoA) showed that the communities of epilithic algae in the control group and in the low concentration group were significantly (P < 0.05) different from that of the high concentration group during the initial 4 days. After 8 days' exposure, all groups tended to be similar, indicating that epilithon showed rapid adaptability and/or resilience. Similar results were found for the relative abundance of some epilithic algae. Our findings indicate that the biofilm system has strong tolerance and adaptability to OTC as it recovered fast after an initial suppression, thus showing the important role of periphyton in maintaining the dynamic balance of nutrients with other processes in aquatic ecosystems.
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Affiliation(s)
- Zhenfang Wang
- Centre for Research on Environmental Ecology and Fish Nutrient of the Ministry of Agriculture, Shanghai Ocean University, Shanghai, 201306, China
| | - Sicheng Yin
- Centre for Research on Environmental Ecology and Fish Nutrient of the Ministry of Agriculture, Shanghai Ocean University, Shanghai, 201306, China
| | - Qingchuan Chou
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, The Chinese Academy of Sciences, Wuhan, 430072, China
| | - Dong Zhou
- Centre for Research on Environmental Ecology and Fish Nutrient of the Ministry of Agriculture, Shanghai Ocean University, Shanghai, 201306, China; Shanghai National Engineering Center of Urban Water Resources CO., LTD, Shanghai, 201306, China
| | - Erik Jeppesen
- Department of Bioscience, Aarhus University, Silkeborg, 8600, Denmark; Sino-Danish Centre for Education and Research (SDC), University of Chinese Academy of Sciences, Beijing, 100049, China; Limnology Laboratory and EKOSAM, Department of Biological Sciences, Middle East Technical University, Ankara, 06800, Turkey; Institute of Marine Sciences, Middle East Technical University, Mersin, 33731, Turkey
| | - Liqing Wang
- Centre for Research on Environmental Ecology and Fish Nutrient of the Ministry of Agriculture, Shanghai Ocean University, Shanghai, 201306, China
| | - Wei Zhang
- Centre for Research on Environmental Ecology and Fish Nutrient of the Ministry of Agriculture, Shanghai Ocean University, Shanghai, 201306, China.
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