DOCSLIB.ORG

Redalyc.DENITRIFICATION of WASTEWATER TREATMENT PLANT EFFLUENT USING ANAEROBIC BACTERIAL BED REACTOR IMMERSED: OPERATING PERFO

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Redalyc.DENITRIFICATION of WASTEWATER TREATMENT PLANT EFFLUENT USING ANAEROBIC BACTERIAL BED REACTOR IMMERSED: OPERATING PERFO Journal of Urban and Environmental Engineering E-ISSN: 1982-3932 [email protected] Universidade Federal da Paraíba Brasil Sylla, Aboubacar; Fatima Ezzahra, Aboussabiq; Najwa, Hassou; Rihani, Mohamed; Jamal, Amine; Omar, Assobhei; Samira, Etahiri DENITRIFICATION OF WASTEWATER TREATMENT PLANT EFFLUENT USING ANAEROBIC BACTERIAL BED REACTOR IMMERSED: OPERATING PERFORMANCE Journal of Urban and Environmental Engineering, vol. 11, núm. 2, julio-diciembre, 2017, pp. 208-218 Universidade Federal da Paraíba Paraíba, Brasil Available in: http://www.redalyc.org/articulo.oa?id=283255970009 How to cite Complete issue Scientific Information System More information about this article Network of Scientific Journals from Latin America, the Caribbean, Spain and Portugal Journal's homepage in redalyc.org Non-profit academic project, developed under the open access initiative Journal of Urban and Environmental Journal of Urban and E Engineering, v.11, n.2, p.208-218 Environmental Engineering ISSN 1982-3932 J www.journal-uee.org E doi: 10.4090/juee.2017.v11n2.208218 U DENITRIFICATION OF WASTEWATER TREATMENT PLANT EFFLUENT USING ANAEROBIC BACTERIAL BED REACTOR IMMERSED: OPERATING PERFORMANCE Aboubacar Sylla*, Aboussabiq Fatima Ezzahra, Hassou Najwa, Mohamed Rihani, Amine Jamal, Assobhei Omar and Etahiri Samira BIOMARE Laboratory, Biology Department, Faculty of Science, University Chouaib Doukkali, P.O. Box 20, El Jadida 2400, Morocco. Received 27 August 2016; received in revised form 02 May 2017; accepted 05 July 2017 Abstract: In this study, a heterotrophic denitrification was designed for domestic wastewater treatment with unexpected water flows at different loading rates. Benefited from excellent removal ability COD, shorten operating time and lower maintenance cost. During the time of operation (six months), injection of nitrate was made in the influent RALBI 1 while the RALBI 2 was fed with sewage without addition of nitrate. The COD concentration in the influent of the two reactors was the same. This two reactors (RALBI1 and RALBI2) were fed with real wastewater for 172 days at 6 h HRT, the average COD removal were 71.55% and 54.82% for RALBI1 and RALBI2 respectively. The results showed that RALBI1 has good removal performance for COD compared with RALBI2. This could be due the injected nitrate in RALBI1 whose effect has further stimulated the activity of denitrifying bacteria. Keywords: Heterotrophic denitrification; domestic wastewater; treatment; nitrate; organic matter © 2017 Journal of Urban and Environmental Engineering (JUEE). All rights reserved.. Correspondence to: Aboubacar Sylla, Tel.: 12674173819. E-mail: [email protected] Journal of Urban and Environmental Engineering (JUEE), v.11, n.2, p.208-218, 2017 Aboubacar, Ezzahra, Najwa, Mohamed, Jamal, Omar and Samira 209 INTRODUCTION for activated sludge process or even wastewater disinfection to remove germs in a aim reuse this water Today’s world major challenge is the awareness of are relatively expensive and not always within the reach preserving our living environment from an increasingly of developing countries like Morocco. growing global warming, causing ecological imbalances Thus, it was necessary to develop reliable with rise in temperatures, flood, drought and especially technologies based on an anaerobic system developed pollution of vital resources for human survival like air, lately. This system has been successfully applied for the water and environment. The shortage of water resources treatment of wastewater from low resistance, such as has become an exacerbating issue around the world as a domestic wastewater in Morocco, which could be an result of accelerated industrialization and urban growth alternative to conventional aerobic processes. These as well as changed climatic conditions (Hao et al., 2013; processes are frequently used since they are more Wu et al., 2012).These effects are more pronounced in economic and environmentally friendly, using poor countries where the availability of water resources, optimized natural pathways to actually destroy is significantly seen due to severe water supply pollution, not only transform it into another form imbalance caused by the uneven distribution of rainfall, (Cristóvão et al., 2015; Gotvajn et al., 2005). As a increased in irrigation water demands and high result, the effective denitrification of wastewater temperatures is the case in Countries in the Middle East treatment plant effluent is of fundamental importance. and North of Africa (Sánchez et al., 2007). In fact, the Biological denitrification is normally conducted by pressure on available resources amplifies water facultative anaerobes which are in essential need for degradation (Goh et al., 2015; WWAP, 2012) , due to some food and energy sources which are organic or an excessive consumption and high polluting inorganic (Cast & Flora, 1998; Rijn et al., 2006; production, generating huge amounts of polluted water Moukhlissi et al., 2014). This process is an efficient, that are subsequently released into the environment where heterotrophic bacteria convert NO -N to N . without any treatment. Among various measures of 3 2 There are studies concentrating on autotrophic addressing this challenging problem is the wastewater denitrification in treatment of wastewater. However, reclamation (Goh et al., 2015; Yi et al., 2011, Hao et very few real application of heterotrophic denitrification al., 2013). Hence the urgent need of implementing process was found, especially in the developing effective treatment of domestic wastewater in small countries, probably because this process requires towns, for example Water Framework Directives sufficient external carbon sources for the nitrate 2000/60/EC (European Parliament and Council, 2000) removal (Her & Huang, 1995; Park et al., 2015). in developed countries. Moreover, almost no study has been carried out on The reclaimed water from municipal wastewater reduction of organic matter by the heterotrophic treatment plant (WWTP) can serve for many purposes, denitrification process. There is no detailed information such as urban scenic and landscape greening, urban lake on the utilization of this process for the treatment of and river water replenishment, car washing, domestic wastewater at a relatively short retention time construction site water use, urban road sprinkling, and under the natural temperature and pH conditions. industrial circulating cooling water use, irrigation water Reactor performance is not the unique parameter to be use (Tahri et al., 2010; Angelakis et al., 1999), and the considered in the choice of a heterotrophic recharge of groundwater (Llanos et al., 2015; Hao et al., denitrification system. Capital, operation and 2013, Hao et al., 2013). In general, the quality of treated management costs are important factors which and reused water is affected by the available treatment determine the actual feasibility of a treatment system. processes whereas many pollutants could not be The objectives of this study were : (1) to investigate the thoroughly removed (Hao et al., 2013). A treatment feasibility of heterotrophic denitrification in domestic process suitable to treat or valorize and recycle this wastewater treatment; (2) to find out the effect of nitrate wastewater must be found (Cristóvão et al., 2015). In concentration, organic loading rate (OLR), on organic Morocco wastewater systems are often a huge problem matter (COD) removal efficiency. especially in small community who use dirty water without treatment (Tahri et al. 2010). The wastewater treatment technologies such as ultrafiltration, reverse Material and methods osmosis, ion exchange, electro dialysis, and membrane Wastewater characterization filtration are efficient (Koide & Satta, 2004). However, these technologies have high operational and The power of the device studied was wastewater from maintenance costs. However, biological treatment is the the sewer system of the Faculty of Sciences of El most common process used to treat organics-containing Jadida. The wastewater is fed by a pump to the basin wastewaters (Cristóvão et al., 2015; Christensen et al., will be freed which pretreatment of a high proportion of 2009). Moreover, in some cases the cost per inhabitant mineral or organic suspended solids and sludge by Journal of Urban and Environmental Engineering (JUEE), v.11, n.2, p.208-218, 2017 Aboubacar, Ezzahra, Najwa, Mohamed, Jamal, Omar and Samira 210 settling, before being pumped to the settler. The settler and evaluate the performance of bioreactor for in turn ensures the removal of solid contaminants in heterotrophic denitrification of domestic wastewater. As suspension, which still persist in the wastewater by shown in Fig. 1, the pilot plant bioreactor wastewater settling. At these two stages, the wastewater is free of treatment consists of a tank (1), decanter (3) and two the major part of the pollution in suspension and ready cylindrical (4) vessel having an internal volume of 4 m3. to be fed to the bioreactors. All these stages are Using a peristaltic pump, wastewater was pumped from equipped with a by Controlled electromechanical the influent tank into tank and into two bioreactors control panel to provide a continuous and automatic through its bottom inlet, and flew through the biofilm on system for the treatment of wastewater. Figure 1 shows PVC filler, and then flew out from the upper of the the reactor setup and the influent water characteristics reactor. A inside bioreactors (RALBI1 and 2) immersed are shown in Table
Load more

Recommended publications
  • Municipal Wastewater Denitrification Evaluation City of Windom, Minnesota
    Municipal Wastewater Denitrification Evaluation City of Windom, Minnesota July 29, 2016 – Revised November 4, 2016 Bolton & Menk, Inc. Project No. T22.109023 Prepared by: Submitted by: Bolton & Menk, Inc. 12224 Nicollet Blvd Burnsvillle, MN 55337 P: 952-890-0509 F: 952-890-8065 wq-wwtp5-91 MUNICIPAL WASTEWATER DENITRIFICATION EVALUATION CITY OF WINDOM, MINNESOTA JULY 2016 BMI Project No. T22.109023 I hereby certify that this plan, specification or report was prepared by me or under my direct supervision, and that I am a duly Licensed Professional Engineer under the laws of the State of Minnesota. Signature: Typed or Printed Name: Lana Tullis, P.E. Date: July 29, 2016 Lic. No. 41450 I hereby certify that this plan, specification or report was prepared by me or under my direct supervision, and that I am a duly Licensed Professional Engineer under the laws of the State of Minnesota. Signature: Typed or Printed Name: Herman Dharmarajah, Ph.D., P.E. Date: July 29, 2016 Lic. No. 18256 I hereby certify that this plan, specification or report was prepared by me or under my direct supervision, and that I am a duly Licensed Professional Engineer under the laws of the State of Minnesota. BOLTON & MENK, INC. CONSULTING ENGINEERS AND LAND SURVEYORS This page intentionally left blank. TABLE OF CONTENTS SECTION 1 INTRODUCTION ............................................................................................... 1-1 A. Project Background ........................................................................................ 1-1 B. Nitrate Standards
    [Show full text]
  • Nitrogen Transformations in Wetlands: Effects of Water Flow Patterns
    S£ 9807//6 Nitrogen transformations in wetlands: Effects of water flow patterns Department of Ecology Limnology Lund University, Sweden Lund 1997 DISCLAIMER Portions of this document may be illegible electronic image products. Images are produced from the best available original document. Organization Document name LUND UNIVERSITY DOCTORAL DISSERTATION Department ofEcology Limnology Date of Issue November 14. 1997 S-223 62 Lund Sweden SE-LUNBDS/NBLL-97/1032-t-l 14pp Authors) Sponsoring organization Torbjorn Davidsson Title and subtitle Nitrogen transformations in wetlands: Effects of water Bow patterns Abstract In this thesis, 1 have studied nitrogen turnover processes in watermcadows. A watcrmcadow is a wetland where water infiltrates through the soil of a grassland field. It is hypothesized that infiltration of water through the soil matrix promotes nutrient transformations compared to surface flow of water, by increasing the contact between water, nutrients, soil organic matter and bacteria. 1 have studied how the balance between nitrogen removal (denitrification, assimilative uptake, adsorption) and release (mineralization, desorption) processes arc affected by water How characteristics. Mass balance studies and direct denitrification measurements at two field sites showed that, although denitrification was high, net nitrogen removal in the watermcadows was poor. This was dueto release of ammonium and dissolved organic nitrogen (DON) from the soils. In laboratory studies, using ,5 N isotope techniques, I have shown that nitrogen turnover is considerably affected by hydrological conditions and by soil type. Infiltration increased virtually all the nitrogen processes, due to deeper penetration of nitrate and oxygen, and extended zones of turnover processes. On the contrary, soils and sediments with surface waterflow, diffusion is the main transfer mechanism.
    [Show full text]
  • Minimization of N2O Emission Through Intermittent Aeration in a Sequencing Batch Reactor (SBR): Main Behavior and Mechanism
    water Article Minimization of N2O Emission through Intermittent Aeration in a Sequencing Batch Reactor (SBR): Main Behavior and Mechanism Tang Liu 1, Shufeng Liu 1,*, Shishi He 2, Zhichao Tian 2 and Maosheng Zheng 2 1 College of Environmental Sciences and Engineering, Peking University, Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing 100871, China; [email protected] 2 College of Environmental Science and Technology, North China Electric Power University, Key Laboratory of Resources and Environmental Systems Optimization, Ministry of Education, Beijing 102206, China; [email protected] (S.H.); [email protected] (Z.T.); [email protected] (M.Z.) * Correspondence: [email protected]; Tel.: +86-10-62754292 Abstract: To explore the main behavior and mechanism of minimizing nitrous oxide (N2O) emission through intermittent aeration during wastewater treatment, two lab-scale sequencing batch reac- tors operated at intermittently aerated mode (SBR1), and continuously aerated mode (SBR2) were established. Compared with SBR2, the intermittently aerated SBR1 reached not only a higher total nitrogen removal efficiency (averaged 93.5%) but also a lower N2O-emission factor (0.01–0.53% of influent ammonia), in which short-cut nitrification and denitrification were promoted. Moreover, less accumulation and consumption of polyhydroxyalkanoates, a potential endogenous carbon source promoting N2O emission, were observed in SBR1. Batch experiments revealed that nitrifier denitrifi- cation was the major pathway generating N2O while heterotrophic denitrification played as a sink of N2O, and SBR1 embraced a larger N2O-mitigating capability. Finally, quantitative polymerase chain reaction results suggested that the abundant complete ammonia oxidizer (comammox) ele- vated in the intermittently aerated environment played a potential role in avoiding N2O generation during wastewater treatment.
    [Show full text]
  • External Carbon Sources for Nitrogen Removal
    United States Environmental Protection Agency August 2013 Wastewater Treatment Fact Sheet: External Carbon Sources for Nitrogen Removal DESCRIPTION Discharge permits for publicly owned treatment There are two major sources of organic carbon works (POTWs) and industries often include utilized in wastewater treatment operations. effluent limits for nutrients, including nitrogen. The sources are defined with respect to Total maximum daily loads (TMDLs) for whether they originate within the influent nutrients have and are being developed for many wastewater entering the treatment facility or water bodies throughout the United States. The are provided as an external supplemental TMDLs and resultant waste load allocations to carbon source added to the treatment system. protect impaired water bodies have resulted in Carbon sources are termed external when the more stringent effluent limits for total nitrogen. carbon substrate is sourced from outside the wastewater treatment process i.e., it is not In order to achieve very low total nitrogen limits derived from the influent wastewater or any of less than 6 mg/l through biological onsite treatment processes at the treatment denitrification, a readily biodegradable carbon facility. External supplemental carbon sources source must be available for the denitrifying are brought into the wastewater treatment organisms to use. A supplemental external process usually as pure compounds or high carbon source is often required when organic strength waste materials where concentrations material in the wastewater has been oxidized. can be as high as 1.5 g/L chemical oxygen This is especially true in denitrification processes demand (COD) to facilitate nutrient removal. that are located after the aeration process such Internal carbon sources refer to organic as post or second anoxic zone and denitrifying carbon substrates obtained either within filters.
    [Show full text]
  • Denitrification: from Genes to Ecosystems
    Denitrification: From Genes to Ecosystems Christopher M. Jones Faculty of Natural Resources and Agricultural Sciences Department of Microbiology Uppsala Doctoral Thesis Swedish University of Agricultural Sciences Uppsala 2010 Acta Universitatis agriculturae Sueciae 2010:83 Cover: Montage showing the phylogeny of globally distributed nirS sequences, where tip labels indicate habitat type (see Figure 6, this thesis). Earth photo courtesy of NASA. ISSN 1652-6880 ISBN 978-91-576-7528-6 © 2010 Christopher M. Jones, Uppsala Print: SLU Service/Repro, Uppsala 2010 Denitrification: From Genes to Ecosystems Abstract Denitrification is a part of the global nitrogen cycle in which fixed nitrogen in the biosphere is returned to the atmosphere, and is mediated by diverse communities of microorganisms. This thesis seeks to gain a greater understanding of the ecology of denitrifying microorganisms by examining the pathway from four different aspects; gene, population, community, and ecosystem. A combination of bioinformatic analysis of denitrification genes in pure cultures and environmental samples as well as experimental work with denitrifying bacterial cultures and soil microcosms was performed to understand the relationship between genes and ecosystems in denitrification. Analysis of the phylogeny of genes involved in key steps in the denitrificaiton pathway revealed a different evolutionary pattern for each gene, as processes such as horizontal gene transfer, duplication/divergence, and lineage sorting have contributed differentially to the evolution of catalytic genes at each step. However, genetic variation is not easily translated into an extended phenotype for a population of denitrifiers, as the denitrification phenotype of a set of closely related denitrifying Bacillus soil isolates was variable depending on pH.
    [Show full text]
  • Denitrification, Nutrient Regeneration and Carbon Mineralization in Sediments of Galveston Bay, Texas, USA
    I MARINE ECOLOGY PROGRESS SERIES Vol. 114: 275-288,1994 Published November l7 Mar. Ecol. Prog. Ser. Denitrification, nutrient regeneration and carbon mineralization in sediments of Galveston Bay, Texas, USA Andrew R. Zimmerman*, Ronald Benner ** Marine Science Institute. University of Texas at Austin, Port Aransas. Texas 78373, USA ABSTRACT: Rates of benthic denitrification, oxygen consumption and nutrient regeneration were measured during winter, spring and summer in Galveston Bay (Texas, USA) sediments. Denitrification ranged from 0 to 47 pm01 N2 m-2 h-' with maximal rates generally occurring in the summer and the upper estuary. Oxygen consumption rates ranged from 38 pm01 O2 m-2 h-' in the winter to 353 pm01 O2 m-' h-' in the summer and were correlated with denitrification rates. Variations in bay water tem- perature accounted for 52 % of the variability associated with denitrification rates whereas only 28% of the variability could be attributed to organic carbon content and 15% to salinity, indicating a pre- dominance of temporal over spatial factors in controlling estuarine rates of denitrification. In the spring and summer, denitrification was responsible for the majority (73 and 80%, respectively) of the total benthic inorganic nitrogen efflux while in the winter, nitrogen fluxes were dominated (80 %) by ammo- nium. At salinities less than 6L, cation exchange interactions may have played an important role in retaining ammonium in the sediment, producing the higher rates of denitrification found in the upper estuary. Dissolved inorganic carbon flux was used as a measure of total organic carbon mineralization. The average molar C:N of the remineralized substrate (5.2) was lower than the average C:N of the sediments (12.6) indicating preferent~alremineralization of nitrogen relative to carbon.
    [Show full text]
  • Nitrous-Oxide Production Partitioned Between Nitrification And
    Geophysical Research Abstracts Vol. 21, EGU2019-17970, 2019 EGU General Assembly 2019 © Author(s) 2019. CC Attribution 4.0 license. Nitrous-oxide production partitioned between nitrification and denitrification over the soil-moisture range of the world’s peatlands Jaan Pärn (1), Fotis Sgouridis (2), and Sami Ullah () (1) Department of Geography, Institute of Ecology and Earth Sciences, University of Tartu, Estonia ([email protected]), (2) School of Geographical Sciences, University of Bristol, United Kingdom, (3) School of Geography, Earth and Environmental Sciences, University of Birmingham, United Kingdom Emission of nitrous oxide (N2O), a powerful greenhouse gas and the leading stratospheric-ozone depleter from nitrogen- (N) rich organic soil peaks at intermediate (50% volumetric) soil moisture. Nitrification (oxidation of ammonia (NH4)) and denitrification (reduction of nitrate (NO3)) are the dominant sources of N2O production in soils and their contribution to net N2O emission, in addition to other soil factors, is affected by the degree of saturation with water and subsequently oxygen. Therefore, knowing the effects of soil moisture on the relative contribution of denitrification and nitrification to N2O emission from organic soils across the world could identify management action to reduce N2O emissions. We utilised our library of organic-soil samples collected from 21 peatland sites across the world, tropical to boreal 15 climates. We source-partitioned N2O production in the laboratory using the N gas-flux method in a factorial design representing the full globally observed range of organic-soil moisture and N content. For the source parti- 15 + 15 − + 15 − tioning, we added either NH4 or NO3 (at ∼ 20 % of the ambient soil NH4 and NO3 concentration) in two separate 30g aliquots while retaining the ambient moisture content.
    [Show full text]
  • Nitrogen Regulation by Natural Systems in “Unnatural” Landscapes: Denitrification in Ultra- Urban Coastal Ecosystems
    Ecosystem Health and Sustainability ISSN: 2096-4129 (Print) 2332-8878 (Online) Journal homepage: http://www.tandfonline.com/loi/tehs20 Nitrogen regulation by natural systems in “unnatural” landscapes: denitrification in ultra- urban coastal ecosystems Bernice R. Rosenzweig, Peter M. Groffman, Chester B. Zarnoch, Brett F. Branco, Ellen K. Hartig, James Fitzpatrick, Helen M. Forgione & Adam Parris To cite this article: Bernice R. Rosenzweig, Peter M. Groffman, Chester B. Zarnoch, Brett F. Branco, Ellen K. Hartig, James Fitzpatrick, Helen M. Forgione & Adam Parris (2018) Nitrogen regulation by natural systems in “unnatural” landscapes: denitrification in ultra-urban coastal ecosystems, Ecosystem Health and Sustainability, 4:9, 205-224, DOI: 10.1080/20964129.2018.1527188 To link to this article: https://doi.org/10.1080/20964129.2018.1527188 © 2018 The Author (s). Published by Taylor & Francis Group and Science Press on behalf of the Ecological Society of China. Published online: 17 Oct 2018. Submit your article to this journal Article views: 149 View Crossmark data Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=tehs20 ECOSYSTEM HEALTH AND SUSTAINABILITY 2018, VOL. 4, NO. 9, 205–224 https://doi.org/10.1080/20964129.2018.1527188 Nitrogen regulation by natural systems in “unnatural” landscapes: denitrification in ultra-urban coastal ecosystems Bernice R. Rosenzweiga, Peter M. Groffmana,b,c, Chester B. Zarnochd, Brett F. Brancob, Ellen K. Hartige, James Fitzpatrickf,
    [Show full text]
  • Marine Microorganisms and Global Nutrient Cycles Kevin R
    03 Arrigo 15-21 6/9/05 11:17 AM Page 15 NATURE|Vol 437|15 September 2005|doi:10.1038/nature04158 INSIGHT REVIEW Marine microorganisms and global nutrient cycles Kevin R. Arrigo1 The way that nutrients cycle through atmospheric, terrestrial, oceanic and associated biotic reservoirs can constrain rates of biological production and help structure ecosystems on land and in the sea. On a global scale, cycling of nutrients also affects the concentration of atmospheric carbon dioxide. Because of their capacity for rapid growth, marine microorganisms are a major component of global nutrient cycles. Understanding what controls their distributions and their diverse suite of nutrient transformations is a major challenge facing contemporary biological oceanographers. What is emerging is an appreciation of the previously unknown degree of complexity within the marine microbial community. To understand how carbon and nutrients, such as nitrogen and phos- through the activities of marine phytoplankton. phorus, cycle through the atmosphere, land and oceans, we need a Unfortunately, a clear mechanism explaining the observed magni- clearer picture of the underlying processes. This is particularly impor- tude of the Redfield C:N:P ratio of 106:16:1 for either phytoplankton tant in the face of increasing anthropogenic nutrient release and or the deep ocean has been elusive. It has long been recognized that climate change. Marine microbes, which are responsible for approxi- conditions exist under which phytoplankton stoichiometry diverges mately half of the
    [Show full text]
  • Denitrification and Associated Nitrous Oxide and Carbon Dioxide
    Biogeosciences, 17, 4297–4311, 2020 https://doi.org/10.5194/bg-17-4297-2020 © Author(s) 2020. This work is distributed under the Creative Commons Attribution 4.0 License. Denitrification and associated nitrous oxide and carbon dioxide emissions from the Amazonian wetlands Jérémy Guilhen1,2, Ahmad Al Bitar2, Sabine Sauvage1, Marie Parrens2,3, Jean-Michel Martinez4, Gwenael Abril5,6, Patricia Moreira-Turcq7, and José-Miguel Sánchez-Pérez1 1Laboratoire Écologie Fonctionnelle et Environnement, Institut national polytechnique de Toulouse (INPT), CNRS, Université de Toulouse (UPS), Toulouse, France 2Centre d’Etudes Spatiales de la Biosphère (CESBIO), CNES, Université de Toulouse (UPS), Toulouse, France 3Dynafor, Université de Toulouse, INRAE, INPT, INP-PURPAN, Castanet-Tolosan, France 4Géosciences Environnement Toulouse (GET), IRD–CNRS, Université Toulouse (UPS), Toulouse, France 5Biologie des Organismes et Ecosystèmes Aquatiques (BOREA), Muséum National d’Histoire Naturelle, Paris, France 6Programa de Geoquímica, Universidade Federal Fluminense, Outeiro São João Batista, Niterói, RJ, Brazil 7Institut de Recherche pour le Développement (IRD), Géosciences Environnement Toulouse (GET), UMR 5563, Lima, Peru Correspondence: Jérémy Guilhen ([email protected]) and Sabine Sauvage ([email protected]) Received: 9 January 2020 – Discussion started: 12 February 2020 Revised: 7 July 2020 – Accepted: 16 July 2020 – Published: 28 August 2020 Abstract. In this paper, we quantify the CO2 and N2O emis- When compared to other wetlands in different pedoclimatic sions from denitrification over the Amazonian wetlands. The environments we found that the Amazonian wetlands have study concerns the entire Amazonian wetland ecosystem similar emissions of N2O with the Congo tropical wetlands with a specific focus on three floodplain (FP) locations: the and lower emissions than the temperate and tropical anthro- Branco FP, the Madeira FP and the FP alongside the Ama- pogenic wetlands of the Garonne (France), the Rhine (Eu- zon River.
    [Show full text]
  • Control Factors of the Marine Nitrogen Cycle
    Control factors of the marine nitrogen cycle The role of meiofauna, macrofauna, oxygen and aggregates Stefano Bonaglia Academic dissertation for the Degree of Doctor of Philosophy in Geochemistry at Stockholm University to be publicly defended on Wednesday 29 April 2015 at 13.00 in Nordenskiöldsalen, Geovetenskapens hus, Svante Arrhenius väg 12. Abstract The ocean is the most extended biome present on our planet. Recent decades have seen a dramatic increase in the number and gravity of threats impacting the ocean, including discharge of pollutants, cultural eutrophication and spread of alien species. It is essential therefore to understand how different impacts may affect the marine realm, its life forms and biogeochemical cycles. The marine nitrogen cycle is of particular importance because nitrogen is the limiting factor in the ocean and a better understanding of its reaction mechanisms and regulation is indispensable. Furthermore, new nitrogen pathways have continuously been described. The scope of this project was to better constrain cause-effect mechanisms of microbially mediated nitrogen pathways, and how these can be affected by biotic and abiotic factors. This thesis demonstrates that meiofauna, the most abundant animal group inhabiting the world’s seafloors, considerably alters nitrogen cycling by enhancing nitrogen loss from the system. In contrast, larger fauna such as the polychaete Marenzelleria spp. enhance nitrogen retention, when they invade eutrophic Baltic Sea sediments. Sediment anoxia, caused by nutrient excess, has negative consequences for ecosystem processes such as nitrogen removal because it stops nitrification, which in turn limits both denitrification and anammox. This was the case of Himmerfjärden and Byfjord, two estuarine systems affected by anthropogenic activities, such as treated sewage discharges.
    [Show full text]
  • Identifying the Mechanisms Behind the Positive Feedback Loop Between Nitrogen Cycling and Algal Blooms in a Shallow Eutrophic Lake
    water Article Identifying the Mechanisms behind the Positive Feedback Loop between Nitrogen Cycling and Algal Blooms in a Shallow Eutrophic Lake Yu Yao 1,2, Huaji Liu 1,2,* , Ruiming Han 1,2 , Dujun Li 1,2 and Limin Zhang 3,4 1 School of Environment, Nanjing Normal University, Nanjing 210023, China; [email protected] (Y.Y.); [email protected] (R.H.); [email protected] (D.L.) 2 Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing 210023, China 3 Green Economy Development Institute, Nanjing University of Finance and Economics, Nanjing 210023, China; [email protected] 4 Jiangsu Engineering Lab of Water and Soil Eco-Remediation, Nanjing Normal University, Nanjing 210023, China * Correspondence: [email protected]; Tel./Fax: +86-025-83787332 Abstract: Algal blooms have increased in frequency, intensity, and duration in response to nitrogen (N) cycling in freshwater ecosystems. We conducted a high-resolution sedimentary study of N transformation and its associated microbial activity in Lake Taihu to assess the accumulation rates of the different N fractions in response to algal blooms, aiming to understand the mechanisms of N cycling in lacustrine environments. Downcore nitrification and denitrification processes were measured simultaneously in situ via diffusive gradients in thin-films technique, peeper, and mi- croelectrode devices in a region of intensified algal blooms of shallow lake. The decomposition of different biomasses of algal blooms did not change the main controlling factor on different N Citation: Yao, Y.; Liu, H.; Han, R.; Li, fractions in profundal sediment. However, the decomposition of different algal biomasses led to D.; Zhang, L.
    [Show full text]