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Piazzolla D, Scanu S, Mancuso FP, Bosch-Belmar M, Bonamano S, Madonia A, Scagnoli E, Tantillo MF, Russi M, Savini A, Fersini G, Sarà G, Coppini G, Marcelli M, Piermattei V. An integrated approach for the benthic habitat mapping based on innovative surveying technologies and ecosystem functioning measurements. Sci Rep 2024; 14:5888. [PMID: 38467723 PMCID: PMC10928125 DOI: 10.1038/s41598-024-56662-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Accepted: 03/08/2024] [Indexed: 03/13/2024] Open
Abstract
Among marine ecosystems globally, those in the Mediterranean Sea, are facing many threats. New technologies are crucial for enhancing our understanding of marine habitats and ecosystems, which can be complex and resource-intensive to analyse using traditional techniques. We tested, for the first time, an integrated multi-platform approach for mapping the coastal benthic habitat in the Civitavecchia (northern Latium, Italy) coastal area. This approach includes the use of an Unmanned Surface Vehicle (USV), a Remote Operated Vehicle (ROV), and in situ measurements of ecosystem functionality. The echosounder data allowed us to reconstruct the distribution of bottom types, as well as the canopy height and coverage of the seagrass Posidonia oceanica. Our study further involved assessing the respiration (Rd) and net primary production (NCP) rates of P. oceanica and its associated community through in situ benthic chamber incubation. By combining these findings with the results of USV surveys, we were able to develop a preliminary spatial distribution model for P. oceanica primary production (PP-SDM). The P. oceanica PP-SDM was applied between the depths of 8 and 10 m in the studied area and the obtained results showed similarities with other sites in the Mediterranean Sea. Though in the early stages, our results highlight the significance of multi-platform observation data for a thorough exploration of marine ecosystems, emphasizing their utility in forecasting biogeochemical processes in the marine environment.
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Affiliation(s)
- Daniele Piazzolla
- CMCC Foundation - Euro-Mediterranean Center on Climate Change, Lecce, Italy.
| | - Sergio Scanu
- CMCC Foundation - Euro-Mediterranean Center on Climate Change, Lecce, Italy
| | - Francesco Paolo Mancuso
- Laboratory of Ecology, Department of Earth and Marine Sciences (DiSTeM), University of Palermo, 90123, Palermo, Italy
- NBFC, National Biodiversity Future Center, Spoke 1, 90133, Palermo, Italy
| | - Mar Bosch-Belmar
- Laboratory of Ecology, Department of Earth and Marine Sciences (DiSTeM), University of Palermo, 90123, Palermo, Italy
- NBFC, National Biodiversity Future Center, Spoke 1, 90133, Palermo, Italy
| | - Simone Bonamano
- Laboratory of Experimental Oceanology and Marine Ecology, Department of Ecological and Biological Sciences DEB, University of Tuscia, Port of Civitavecchia, 00053, Civitavecchia, Italy
| | - Alice Madonia
- CMCC Foundation - Euro-Mediterranean Center on Climate Change, Lecce, Italy
| | - Elena Scagnoli
- Laboratory of Experimental Oceanology and Marine Ecology, Department of Ecological and Biological Sciences DEB, University of Tuscia, Port of Civitavecchia, 00053, Civitavecchia, Italy
| | - Mario Francesco Tantillo
- Laboratory of Ecology, Department of Earth and Marine Sciences (DiSTeM), University of Palermo, 90123, Palermo, Italy
- NBFC, National Biodiversity Future Center, Spoke 1, 90133, Palermo, Italy
| | - Martina Russi
- Laboratory of Ecology, Department of Earth and Marine Sciences (DiSTeM), University of Palermo, 90123, Palermo, Italy
- NBFC, National Biodiversity Future Center, Spoke 1, 90133, Palermo, Italy
| | - Alessandra Savini
- Department of Earth and Environmental Sciences (DISAT), University of Milano-Bicocca, 20126, Milan, Italy
| | - Giorgio Fersini
- Port Authority System of the Central Northern Tyrrhenian Sea, 00053, Civitavecchia, Italy
| | - Gianluca Sarà
- Laboratory of Ecology, Department of Earth and Marine Sciences (DiSTeM), University of Palermo, 90123, Palermo, Italy
- NBFC, National Biodiversity Future Center, Spoke 1, 90133, Palermo, Italy
| | - Giovanni Coppini
- CMCC Foundation - Euro-Mediterranean Center on Climate Change, Lecce, Italy
| | - Marco Marcelli
- CMCC Foundation - Euro-Mediterranean Center on Climate Change, Lecce, Italy
- Laboratory of Experimental Oceanology and Marine Ecology, Department of Ecological and Biological Sciences DEB, University of Tuscia, Port of Civitavecchia, 00053, Civitavecchia, Italy
| | - Viviana Piermattei
- CMCC Foundation - Euro-Mediterranean Center on Climate Change, Lecce, Italy
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Olander A, Raina JB, Lawson CA, Bartels N, Ueland M, Suggett DJ. Distinct emissions of biogenic volatile organic compounds from temperate benthic taxa. Metabolomics 2023; 20:9. [PMID: 38129550 DOI: 10.1007/s11306-023-02070-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Accepted: 11/28/2023] [Indexed: 12/23/2023]
Abstract
INTRODUCTION Biogenic volatile organic compounds (BVOCs) are emitted by all organisms as intermediate or end-products of metabolic processes. Individual BVOCs perform important physiological, ecological and climatic functions, and collectively constitute the volatilome-which can be reflective of organism taxonomy and health. Although BVOC emissions of tropical benthic reef taxa have recently been the focus of multiple studies, emissions derived from their temperate counterparts have never been characterised. OBJECTIVES Characterise the volatilomes of key competitors for benthic space among Australian temperate reefs. METHODS Six fragments/fronds of a temperate coral (Plesiastrea versipora) and a macroalga (Ecklonia radiata) from a Sydney reef site were placed within modified incubation chambers filled with seawater. Organism-produced BVOCs were captured on thermal desorption tubes using a purge-and-trap methodology, and were then analysed using GC × GC - TOFMS and multivariate tests. RESULTS Analysis detected 55 and 63 BVOCs from P. versipora and E. radiata respectively, with 30 of these common between species. Each taxon was characterised by a similar relative composition of chemical classes within their volatilomes. However, 14 and 10 volatiles were distinctly emitted by either E. radiata or P. versipora respectively, including the halogenated compounds iodomethane, tribromomethane, carbon tetrachloride and trichloromonofluoromethane. While macroalgal cover was 3.7 times greater than coral cover at the sampling site, P. versipora produced on average 17 times more BVOCs per cm2 of live tissue, resulting in an estimated contribution to local BVOC emission that was 4.7 times higher than E. radiata. CONCLUSION Shifts in benthic community composition could disproportionately impact local marine chemistry and affect how ecosystems contribute to broader BVOC emissions.
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Affiliation(s)
- Axel Olander
- Climate Change Cluster, University of Technology Sydney, Broadway, NSW, 2007, Australia.
| | - Jean-Baptiste Raina
- Climate Change Cluster, University of Technology Sydney, Broadway, NSW, 2007, Australia
| | - Caitlin A Lawson
- Climate Change Cluster, University of Technology Sydney, Broadway, NSW, 2007, Australia
- School of Environmental and Life Sciences, University of Newcastle, Newcastle, NSW, Australia
| | - Natasha Bartels
- Climate Change Cluster, University of Technology Sydney, Broadway, NSW, 2007, Australia
| | - Maiken Ueland
- Centre for Forensic Science, University of Technology Sydney, Broadway, NSW, 2007, Australia
| | - David J Suggett
- Climate Change Cluster, University of Technology Sydney, Broadway, NSW, 2007, Australia
- KAUST Reefscape Restoration Initiative (KRRI) and Red Sea Research Center (RSRC), King Abdullah University of Science and Technology, 23955, Thuwal, Saudi Arabia
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3
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Mancuso FP, Giommi C, Mangano MC, Airoldi L, Helmuth B, Sarà G. Evenness, biodiversity, and ecosystem function of intertidal communities along the Italian coasts: Experimental short-term response to ambient and extreme air temperatures. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 858:160037. [PMID: 36356730 DOI: 10.1016/j.scitotenv.2022.160037] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 11/03/2022] [Accepted: 11/03/2022] [Indexed: 06/16/2023]
Abstract
Biodiversity can promote ecosystem functioning in both terrestrial and marine environments, emphasizing the necessity of biodiversity conservation in order to preserve critical ecosystem functions and associated services. However, the role of biodiversity in buffering ecosystem functioning under extreme events caused by climate change remains a major scientific issue, especially for intertidal systems experiencing stressors from both terrestrial and marine drivers. We performed a regional-scale field experiment along the Italian coast to investigate the response of unmanipulated intertidal communities (by using a natural biodiversity gradient) to low tide aerial exposure to both ambient and short-term extreme temperatures. We specifically investigated the relationship between Biodiversity and Ecosystem Functioning (BEF) using different biodiversity indexes (species richness, functional diversity and evenness) and the response of the intertidal communities' ecosystem functioning (community respiration rates). Furthermore, we investigated which other environmental variables could influence the BEF relationship. We show that evenness explained a greater variation in intertidal community ecosystem functioning under both temperature conditions. Species richness (the most often used diversity metric in BEF research) was unrelated to ecosystem functioning, while functional diversity was significantly related to respiration under ambient but not extreme temperatures. We highlight the importance of the short-term thermal history of the communities (measured as body temperature) in the BEF relationship as it was consistently identified as the best predictor or response under both temperature conditions. However, Chlorophyll a in seawater and variation in sea surface temperature also contributed to the BEF relationship under ambient but not under extreme conditions, showing that short-duration climate-driven events can overcome local physiological adaptations. Our findings support the importance of the BEF relationship in intertidal communities, implying that systems with more diverse and homogeneous communities may be able to mitigate the effects of extreme temperatures.
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Affiliation(s)
- Francesco Paolo Mancuso
- Department of Earth and Marine Sciences (DiSTeM), University of Palermo, viale delle Scienze Ed. 16, 90128 Palermo, Italy; NBFC, National Biodiversity Future Center, Palermo 90133, Italy.
| | - Chiara Giommi
- Department of Earth and Marine Sciences (DiSTeM), University of Palermo, viale delle Scienze Ed. 16, 90128 Palermo, Italy; Department of Integrative Marine Ecology (EMI), Stazione Zoologica Anton Dohrn, CRIMAC, Calabria Marine Centre, Amendolara, Italy
| | - Maria Cristina Mangano
- NBFC, National Biodiversity Future Center, Palermo 90133, Italy; Stazione Zoologica Anton Dohrn, Dipartimento Ecologia Marina Integrata, Sede Interdipartimentale della Sicilia, Lungomare Cristoforo Colombo (complesso Roosevelt), 90142 Palermo, Italy
| | - Laura Airoldi
- Department of Biology, Chioggia Hydrobiological Station Umberto D'Ancona, University of Padova, 30015 Chioggia, Italy; University of Bologna, Dipartimento di Beni Culturali & Centro Interdipartimentale di Ricerca per le Scienze Ambientali (CIRSA), UO CoNISMa, Via S. Alberto, 163, 48123 Ravenna, Italy
| | - Brian Helmuth
- Marine Science Center, Northeastern University, Nahant, MA 01908, USA
| | - Gianluca Sarà
- Department of Earth and Marine Sciences (DiSTeM), University of Palermo, viale delle Scienze Ed. 16, 90128 Palermo, Italy; NBFC, National Biodiversity Future Center, Palermo 90133, Italy
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4
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Filippini G, Dafforn KA, Bugnot AB. Shellfish as a bioremediation tool: A review and meta-analysis. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 316:120614. [PMID: 36356885 DOI: 10.1016/j.envpol.2022.120614] [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: 05/26/2022] [Revised: 10/17/2022] [Accepted: 11/04/2022] [Indexed: 06/16/2023]
Abstract
Over the last century, human activities have increased the amount of nutrients inputs to terrestrial and aquatic ecosystems. These activities have altered nitrogen (N) and phosphorus (P) cycling, causing substantial changes in ecosystem function such as provision of clean air and water. Strategies that reduce and remove excess nutrients are urgently needed to remediate impacted systems. Reef-forming shellfish (oysters and mussels) can play a crucial role in nutrient cycling, particularly in N removal from aquatic systems by providing substrate for microbial colonisation and enhancing microbial denitrification in the surrounding sediments. However, the potential for shellfish to enhance nutrient cycling (and denitrification) will likely vary spatially and in response to several environmental factors. Here, we used 1) a qualitative analysis to review nutrient processes occurring on shellfish; and 2) a meta-analysis to evaluate the influence of shellfish on benthic metabolism and nutrient cycling in surrounding sediments, and how that is influenced by environmental factors such as grain size, seasonality, water body type, and tidal position. Overall, we found that shellfish increased oxygen consumption, with consequent release of ammonia (NH4+) and phosphate (PO43-) from shellfish and their surrounding sediments. These parameters did not depend on grain size, water body type and tidal height, but the release of PO43- was variable between seasons, being highest during summer and autumn. Shellfish presence also enhanced denitrification measured as dinitrogen gas (N2) efflux on both reefs and sediments. Denitrification was highest in lagoons; in sandy sediments; and during the warmest season (summer). Thus, our findings highlight that environmental context can mediate the effects of shellfish reefs on sediment function. This information is important for managers seeking to use these animals as an effective bioremediation tool.
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Affiliation(s)
- Giulia Filippini
- School of Natural Sciences, Macquarie University, North Ryde, NSW, 2109, Australia.
| | - Katherine A Dafforn
- School of Natural Sciences, Macquarie University, North Ryde, NSW, 2109, Australia; Sydney Institute of Marine Science, Mosman, NSW, 2088, Australia
| | - Ana B Bugnot
- School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, 2006, Australia; Commonwealth Scientific and Industrial Research Organisation, Brisbane, QLD, 4001, Australia
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5
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Roik A, Reverter M, Pogoreutz C. A roadmap to understanding diversity and function of coral reef-associated fungi. FEMS Microbiol Rev 2022; 46:6615459. [PMID: 35746877 PMCID: PMC9629503 DOI: 10.1093/femsre/fuac028] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 06/01/2022] [Accepted: 06/14/2022] [Indexed: 01/09/2023] Open
Abstract
Tropical coral reefs are hotspots of marine productivity, owing to the association of reef-building corals with endosymbiotic algae and metabolically diverse bacterial communities. However, the functional importance of fungi, well-known for their contribution to shaping terrestrial ecosystems and global nutrient cycles, remains underexplored on coral reefs. We here conceptualize how fungal functional traits may have facilitated the spread, diversification, and ecological adaptation of marine fungi on coral reefs. We propose that functions of reef-associated fungi may be diverse and go beyond their hitherto described roles of pathogens and bioeroders, including but not limited to reef-scale biogeochemical cycles and the structuring of coral-associated and environmental microbiomes via chemical mediation. Recent technological and conceptual advances will allow the elucidation of the physiological, ecological, and chemical contributions of understudied marine fungi to coral holobiont and reef ecosystem functioning and health and may help provide an outlook for reef management actions.
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Affiliation(s)
- Anna Roik
- Corresponding author: Helmholtz Institute for Functional Marine Biodiversity at the University of Oldenburg (HIFMB), Ammerländer Heerstrasse 231, D-26129 Oldenburg, Germany. E-mail:
| | - Miriam Reverter
- Institute for Chemistry and Biology of the Marine Environment, Carl von Ossietzky University of Oldenburg, Wilhelmshaven, 26046, Germany,School of Biological and Marine Sciences, University of Plymouth, Plymouth PL4 8AA, United Kingdom
| | - Claudia Pogoreutz
- Corresponding author: Laboratory for Biological Geochemistry, School of Architecture, Civil and Environmental Engineering, Ecole Polytechnique Federale de Lausanne (EPFL), 1015 Lausanne, Switzerland.,
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6
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The effects of the nonnative brittle star Ophiothela mirabilis Verrill, 1867 on the feeding performance of an octocoral host in a southwestern Atlantic rocky shore. Biol Invasions 2022. [DOI: 10.1007/s10530-022-02815-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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7
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Mallon J, Banaszak AT, Donachie L, Exton D, Cyronak T, Balke T, Bass AM. A low-cost benthic incubation chamber for in-situ community metabolism measurements. PeerJ 2022; 10:e13116. [PMID: 35402104 PMCID: PMC8992662 DOI: 10.7717/peerj.13116] [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: 01/17/2022] [Accepted: 02/23/2022] [Indexed: 01/12/2023] Open
Abstract
Benthic incubation chambers facilitate in-situ metabolism studies in shallow water environments. They are used to isolate the water surrounding a study organism or community so that changes in water chemistry can be quantified to characterise physiological processes such as photosynthesis, respiration, and calcification. Such field measurements capture the biological processes taking place within the benthic community while incorporating the influence of environmental variables that are often difficult to recreate in ex-situ settings. Variations in benthic chamber designs have evolved for a range of applications. In this study, we built upon previous designs to create a novel chamber, which is (1) low-cost and assembled without specialised equipment, (2) easily reproducible, (3) minimally invasive, (4) adaptable to varied substrates, and (5) comparable with other available designs in performance. We tested the design in the laboratory and field and found that it achieved the outlined objectives. Using non-specialised materials, we were able to construct the chamber at a low cost (under $20 USD per unit), while maintaining similar performance and reproducibility with that of existing designs. Laboratory and field tests demonstrated minimal leakage (2.08 ± 0.78% water exchange over 4 h) and acceptable light transmission (86.9 ± 1.9%), results comparable to those reported for other chambers. In the field, chambers were deployed in a shallow coastal environment in Akumal, Mexico, to measure productivity of seagrass, and coral-, algae-, and sand-dominated reef patches. In both case studies, production rates aligned with those of comparable benthic chamber deployments in the literature and followed established trends with light, the primary driver of benthic metabolism, indicating robust performance under field conditions. We demonstrate that our low-cost benthic chamber design uses locally accessible and minimal resources, is adaptable for a variety of field settings, and can be used to collect reliable and repeatable benthic metabolism data. This chamber has the potential to broaden accessibility and applications of in-situ incubations for future studies.
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Affiliation(s)
- Jennifer Mallon
- School of Geographical and Earth Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Anastazia T. Banaszak
- Unidad Académica de Sistemas Arrecifales, Universidad Nacional Autónoma de México, Puerto Morelos, Quintana Roo, Mexico
| | | | - Dan Exton
- Operation Wallacea, Spilsby, Lincolnshire, United Kingdom
| | - Tyler Cyronak
- Department of Marine and Environmental Sciences, Halmos College of Natural Sciences and Oceanography, Nova Southeastern University, Dania Beach, Florida, United States
| | - Thorsten Balke
- School of Geographical and Earth Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Adrian M. Bass
- School of Geographical and Earth Sciences, University of Glasgow, Glasgow, United Kingdom
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8
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Schrumpf A, Lengerer A, Schmid N, Kazda M. Portable Measurement System for in situ Estimation of Oxygen and Carbon Fluxes of Submerged Plants. FRONTIERS IN PLANT SCIENCE 2021; 12:765089. [PMID: 34804099 PMCID: PMC8604185 DOI: 10.3389/fpls.2021.765089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Accepted: 10/11/2021] [Indexed: 06/13/2023]
Abstract
The metabolism of submerged plants is commonly characterized by oxygen development. The turnover rates of carbon dioxide and other inorganic carbon species, however, are assessed only at distinct points in time after incubation or calculated through shifts in pH and total alkalinity. A novel three parameter measurement system was developed in order to improve this issue and to gain a better understanding of the metabolism of aquatic plants. It allows the simultaneous and continuous assessment of oxygen concentration, partial pressure of carbon dioxide and pH with optical sensors without the need of taking water samples. Plants or plant parts can be enclosed in a chamber, while the surrounding water is either flushed through or circulated within the system. The method was evaluated in regards to measurement time and possible stress reactions during measurement. Its applicability in situ was confirmed with Elodea nuttallii and Ceratophyllum demersum. The measurement system will enable deeper insights into the metabolism and response of aquatic plants to changing environmental conditions, especially related to carbon fixation.
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9
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Roth F, El-Khaled YC, Karcher DB, Rädecker N, Carvalho S, Duarte CM, Silva L, Calleja ML, Morán XAG, Jones BH, Voolstra CR, Wild C. Nutrient pollution enhances productivity and framework dissolution in algae- but not in coral-dominated reef communities. MARINE POLLUTION BULLETIN 2021; 168:112444. [PMID: 33984578 DOI: 10.1016/j.marpolbul.2021.112444] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 04/26/2021] [Accepted: 04/28/2021] [Indexed: 06/12/2023]
Abstract
Ecosystem services provided by coral reefs may be susceptible to the combined effects of benthic species shifts and anthropogenic nutrient pollution, but related field studies are scarce. We thus investigated in situ how dissolved inorganic nutrient enrichment, maintained for two months, affected community-wide biogeochemical functions of intact coral- and degraded algae-dominated reef patches in the central Red Sea. Results from benthic chamber incubations revealed 87% increased gross productivity and a shift from net calcification to dissolution in algae-dominated communities after nutrient enrichment, but the same processes were unaffected by nutrients in neighboring coral communities. Both community types changed from net dissolved organic nitrogen sinks to sources, but the increase in net release was 56% higher in algae-dominated communities. Nutrient pollution may, thus, amplify the effects of community shifts on key ecosystem services of coral reefs, possibly leading to a loss of structurally complex habitats with carbonate dissolution and altered nutrient recycling.
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Affiliation(s)
- Florian Roth
- Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia; Baltic Sea Centre, Stockholm University, Stockholm, Sweden; Tvärminne Zoological Station, University of Helsinki, Helsinki, Finland.
| | - Yusuf C El-Khaled
- Marine Ecology, Faculty of Biology and Chemistry, University of Bremen, Bremen, Germany
| | - Denis B Karcher
- Marine Ecology, Faculty of Biology and Chemistry, University of Bremen, Bremen, Germany; Australian National Centre for the Public Awareness of Science, Australian National University, Canberra, Australia
| | - Nils Rädecker
- Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia; Laboratory for Biological Geochemistry, School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland; Department of Biology, University of Konstanz, Konstanz, Germany
| | - Susana Carvalho
- Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Carlos M Duarte
- Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia; Computational Biology Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Luis Silva
- Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Maria Ll Calleja
- Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia; Department of Climate Geochemistry, Max Planck Institute for Chemistry (MPIC), Mainz, Germany
| | - Xosé Anxelu G Morán
- Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Burton H Jones
- Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Christian R Voolstra
- Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia; Department of Biology, University of Konstanz, Konstanz, Germany
| | - Christian Wild
- Marine Ecology, Faculty of Biology and Chemistry, University of Bremen, Bremen, Germany
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10
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Dellisanti W, Chung JTH, Chow CFY, Wu J, Wells ML, Chan LL. Experimental Techniques to Assess Coral Physiology in situ Under Global and Local Stressors: Current Approaches and Novel Insights. Front Physiol 2021; 12:656562. [PMID: 34163371 PMCID: PMC8215126 DOI: 10.3389/fphys.2021.656562] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Accepted: 04/09/2021] [Indexed: 11/19/2022] Open
Abstract
Coral reefs are declining worldwide due to global changes in the marine environment. The increasing frequency of massive bleaching events in the tropics is highlighting the need to better understand the stages of coral physiological responses to extreme conditions. Moreover, like many other coastal regions, coral reef ecosystems are facing additional localized anthropogenic stressors such as nutrient loading, increased turbidity, and coastal development. Different strategies have been developed to measure the health status of a damaged reef, ranging from the resolution of individual polyps to the entire coral community, but techniques for measuring coral physiology in situ are not yet widely implemented. For instance, while there are many studies of the coral holobiont response in single or limited-number multiple stressor experiments, they provide only partial insights into metabolic performance under more complex and temporally and spatially variable natural conditions. Here, we discuss the current status of coral reefs and their global and local stressors in the context of experimental techniques that measure core processes in coral metabolism (respiration, photosynthesis, and biocalcification) in situ, and their role in indicating the health status of colonies and communities. We highlight the need to improve the capability of in situ studies in order to better understand the resilience and stress response of corals under multiple global and local scale stressors.
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Affiliation(s)
- Walter Dellisanti
- State Key Laboratory of Marine Pollution, City University of Hong Kong, Kowloon, China.,Department of Biomedical Sciences, City University of Hong Kong, Kowloon, China
| | - Jeffery T H Chung
- State Key Laboratory of Marine Pollution, City University of Hong Kong, Kowloon, China
| | - Cher F Y Chow
- State Key Laboratory of Marine Pollution, City University of Hong Kong, Kowloon, China.,Centre for Biological Diversity, Scottish Oceans Institute, School of Biology, University of St Andrews, St Andrews, United Kingdom
| | - Jiajun Wu
- State Key Laboratory of Marine Pollution, City University of Hong Kong, Kowloon, China
| | - Mark L Wells
- School of Marine Sciences, University of Maine, Orono, ME, United States.,State Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, China
| | - Leo L Chan
- State Key Laboratory of Marine Pollution, City University of Hong Kong, Kowloon, China.,Department of Biomedical Sciences, City University of Hong Kong, Kowloon, China.,Hong Kong Branch of Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou, China
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11
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El-Khaled YC, Roth F, Rädecker N, Tilstra A, Karcher DB, Kürten B, Jones BH, Voolstra CR, Wild C. Nitrogen fixation and denitrification activity differ between coral- and algae-dominated Red Sea reefs. Sci Rep 2021; 11:11820. [PMID: 34083565 PMCID: PMC8175748 DOI: 10.1038/s41598-021-90204-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Accepted: 05/07/2021] [Indexed: 11/18/2022] Open
Abstract
Coral reefs experience phase shifts from coral- to algae-dominated benthic communities, which could affect the interplay between processes introducing and removing bioavailable nitrogen. However, the magnitude of such processes, i.e., dinitrogen (N2) fixation and denitrification levels, and their responses to phase shifts remain unknown in coral reefs. We assessed both processes for the dominant species of six benthic categories (hard corals, soft corals, turf algae, coral rubble, biogenic rock, and reef sands) accounting for > 98% of the benthic cover of a central Red Sea coral reef. Rates were extrapolated to the relative benthic cover of the studied organisms in co-occurring coral- and algae-dominated areas of the same reef. In general, benthic categories with high N2 fixation exhibited low denitrification activity. Extrapolated to the respective reef area, turf algae and coral rubble accounted for > 90% of overall N2 fixation, whereas corals contributed to more than half of reef denitrification. Total N2 fixation was twice as high in algae- compared to coral-dominated areas, whereas denitrification levels were similar. We conclude that algae-dominated reefs promote new nitrogen input through enhanced N2 fixation and comparatively low denitrification. The subsequent increased nitrogen availability could support net productivity, resulting in a positive feedback loop that increases the competitive advantage of algae over corals in reefs that experienced a phase shift.
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Affiliation(s)
- Yusuf C El-Khaled
- Marine Ecology Department, Faculty of Biology and Chemistry, University of Bremen, 28359, Bremen, Germany.
| | - Florian Roth
- Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, 23995, Saudi Arabia
- Baltic Sea Centre, Stockholm University, 10691, Stockholm, Sweden
- Faculty of Biological and Environmental Sciences, Tvärminne Zoological Station, University of Helsinki, 00014, Helsinki, Finland
| | - Nils Rädecker
- Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, 23995, Saudi Arabia
- Department of Biology, University of Konstanz, 78457, Konstanz, Germany
- Laboratory for Biological Geochemistry, School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Arjen Tilstra
- Marine Ecology Department, Faculty of Biology and Chemistry, University of Bremen, 28359, Bremen, Germany
| | - Denis B Karcher
- Marine Ecology Department, Faculty of Biology and Chemistry, University of Bremen, 28359, Bremen, Germany
- Australian National Centre for the Public Awareness of Science, Australian National University, ACT, Canberra, 2601, Australia
| | - Benjamin Kürten
- Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, 23995, Saudi Arabia
- Project Management Jülich, Jülich Research Centre GmbH, 18069, Rostock, Germany
| | - Burton H Jones
- Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, 23995, Saudi Arabia
| | - Christian R Voolstra
- Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, 23995, Saudi Arabia
- Department of Biology, University of Konstanz, 78457, Konstanz, Germany
| | - Christian Wild
- Marine Ecology Department, Faculty of Biology and Chemistry, University of Bremen, 28359, Bremen, Germany
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12
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Silva L, Calleja ML, Ivetic S, Huete-Stauffer T, Roth F, Carvalho S, Morán XAG. Heterotrophic bacterioplankton responses in coral- and algae-dominated Red Sea reefs show they might benefit from future regime shift. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 751:141628. [PMID: 32896805 DOI: 10.1016/j.scitotenv.2020.141628] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 08/06/2020] [Accepted: 08/09/2020] [Indexed: 06/11/2023]
Abstract
In coral reefs, dissolved organic matter (DOM) cycling is a critical process for sustaining ecosystem functioning. However, global and local stressors have caused persistent shifts from coral- to algae-dominated benthic communities. The influence of such phase shifts on DOM nature and its utilization by heterotrophic bacterioplankton remains poorly studied. Every second month for one year, we retrieved seawater samples enriched in DOM produced by coral- and algae-dominated benthic communities in a central Red Sea reef during a full annual cycle. Seawater incubations were conducted in the laboratory under in situ temperature and light conditions by inoculating enriched DOM samples with bacterial assemblages collected in the surrounding waters. Dissolved organic carbon (DOC) concentrations were higher in the warmer months (May-September) in both communities, resulting in higher specific growth rates and bacterial growth efficiencies (BGE). However, these high summer values were significantly enhanced in algal-DOM relative to coral-DOM, suggesting the potential for bacterioplankton biomass increase in reefs with algae replacing healthy coral cover under warmer conditions. The potential exacerbation of heterotrophic bacterial activity in the ongoing widespread regime shift from coral- to algae-dominated communities may have detrimental consequences for the overall health of tropical coral reefs.
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Affiliation(s)
- Luis Silva
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Thuwal 23955-6900, Saudi Arabia.
| | - Maria Ll Calleja
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Thuwal 23955-6900, Saudi Arabia; Department of Climate Geochemistry, Max Planck Institute for Chemistry (MPIC), Hahn-Meitner-Weg 1, 55128 Mainz, Germany
| | | | - Tamara Huete-Stauffer
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Thuwal 23955-6900, Saudi Arabia
| | - Florian Roth
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Thuwal 23955-6900, Saudi Arabia; Baltic Sea Centre, Stockholm University, 11418 Stockholm, Sweden; Tvärminne Zoological Station, University of Helsinki, 00100 Helsinki, Finland
| | - Susana Carvalho
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Thuwal 23955-6900, Saudi Arabia
| | - Xosé Anxelu G Morán
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Thuwal 23955-6900, Saudi Arabia
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13
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Roth F, RAdecker N, Carvalho S, Duarte CM, Saderne V, Anton A, Silva L, Calleja ML, MorÁn XAG, Voolstra CR, Kürten B, Jones BH, Wild C. High summer temperatures amplify functional differences between coral- and algae-dominated reef communities. Ecology 2020; 102:e03226. [PMID: 33067806 PMCID: PMC7900985 DOI: 10.1002/ecy.3226] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Revised: 07/06/2020] [Accepted: 08/24/2020] [Indexed: 12/30/2022]
Abstract
Shifts from coral to algal dominance are expected to increase in tropical coral reefs as a result of anthropogenic disturbances. The consequences for key ecosystem functions such as primary productivity, calcification, and nutrient recycling are poorly understood, particularly under changing environmental conditions. We used a novel in situ incubation approach to compare functions of coral‐ and algae‐dominated communities in the central Red Sea bimonthly over an entire year. In situ gross and net community primary productivity, calcification, dissolved organic carbon fluxes, dissolved inorganic nitrogen fluxes, and their respective activation energies were quantified to describe the effects of seasonal changes. Overall, coral‐dominated communities exhibited 30% lower net productivity and 10 times higher calcification than algae‐dominated communities. Estimated activation energies indicated a higher thermal sensitivity of coral‐dominated communities. In these communities, net productivity and calcification were negatively correlated with temperature (>40% and >65% reduction, respectively, with +5°C increase from winter to summer), whereas carbon losses via respiration and dissolved organic carbon release more than doubled at higher temperatures. In contrast, algae‐dominated communities doubled net productivity in summer, while calcification and dissolved organic carbon fluxes were unaffected. These results suggest pronounced changes in community functioning associated with coral‐algal phase shifts. Algae‐dominated communities may outcompete coral‐dominated communities because of their higher productivity and carbon retention to support fast biomass accumulation while compromising the formation of important reef framework structures. Higher temperatures likely amplify these functional differences, indicating a high vulnerability of ecosystem functions of coral‐dominated communities to temperatures even below coral bleaching thresholds. Our results suggest that ocean warming may not only cause but also amplify coral–algal phase shifts in coral reefs.
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Affiliation(s)
- Florian Roth
- Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955, Saudi Arabia.,Baltic Sea Centre, Stockholm University, Stockholm, 10691, Sweden.,Faculty of Biological and Environmental Sciences, Tvärminne Zoological Station, University of Helsinki, Helsinki, 00014, Finland
| | - Nils RAdecker
- Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955, Saudi Arabia.,Department of Biology, University of Konstanz, Konstanz, 78457, Germany.,Laboratory for Biological Geochemistry, School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, 1015, Switzerland
| | - Susana Carvalho
- Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955, Saudi Arabia
| | - Carlos M Duarte
- Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955, Saudi Arabia.,Computational Biology Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955, Saudi Arabia
| | - Vincent Saderne
- Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955, Saudi Arabia
| | - Andrea Anton
- Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955, Saudi Arabia.,Computational Biology Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955, Saudi Arabia
| | - Luis Silva
- Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955, Saudi Arabia
| | - Maria Ll Calleja
- Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955, Saudi Arabia.,Department of Climate Geochemistry, Max Planck Institute for Chemistry (MPIC), Mainz, 55128, Germany
| | - XosÉ Anxelu G MorÁn
- Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955, Saudi Arabia
| | - Christian R Voolstra
- Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955, Saudi Arabia.,Department of Biology, University of Konstanz, Konstanz, 78457, Germany
| | - Benjamin Kürten
- Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955, Saudi Arabia.,Project Management Jülich, Jülich Research Centre GmbH, Rostock, 52425, Germany
| | - Burton H Jones
- Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955, Saudi Arabia
| | - Christian Wild
- Marine Ecology, Faculty of Biology and Chemistry, University of Bremen, Bremen, 28359, Germany
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14
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Furey PC, Lee SS, Clemans DL. Substratum-associated microbiota. WATER ENVIRONMENT RESEARCH : A RESEARCH PUBLICATION OF THE WATER ENVIRONMENT FEDERATION 2020; 92:1629-1648. [PMID: 33463854 DOI: 10.1002/wer.1410] [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: 04/30/2020] [Revised: 07/13/2020] [Accepted: 07/14/2020] [Indexed: 06/12/2023]
Abstract
Highlights of new, interesting, and emerging research findings on substratum-associated microbiota covered from a survey of 2019 literature from primarily freshwaters provide insight into research trends of interest to the Water Environment Federation and others interested in benthic, aquatic environments. Coverage of topics on bottom-associated or attached algae and cyanobacteria, though not comprehensive, includes new methods, taxa new-to-science, nutrient dynamics, auto- and heterotrophic interactions, grazers, bioassessment, herbicides and other pollutants, metal contaminants, and nuisance, and bloom-forming and harmful algae. Coverage of bacteria, also not comprehensive, focuses on the ecology of benthic biofilms and microbial communities, along with the ecology of microbes like Caulobacter crescentus, Rhodobacter, and other freshwater microbial species. Bacterial topics covered also include metagenomics and metatranscriptomics, toxins and pollutants, bacterial pathogens and bacteriophages, and bacterial physiology. Readers may use this literature review to learn about or renew their interest in the recent advances and discoveries regarding substratum-associated microbiota. PRACTITIONER POINTS: This review of literature from 2019 on substratum-associated microbiota presents highlights of findings on algae, cyanobacteria, and bacteria from primarily freshwaters. Coverage of algae and cyanobacteria includes findings on new methods, taxa new to science, nutrient dynamics, auto- and heterotrophic interactions, grazers, bioassessment, herbicides and other pollutants, metal contaminants, and nuisance, bloom-forming and harmful algae. Coverage of bacteria includes findings on ecology of benthic biofilms and microbial communities, the ecology of microbes, metagenomics and metatranscriptomics, toxins and pollutants, bacterial pathogens and bacteriophages, and bacterial physiology. Highlights of new, noteworthy and emerging topics build on those from 2018 and will be of relevance to the Water Environment Federation and others interested in benthic, aquatic environments.
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Affiliation(s)
- Paula C Furey
- Department Biology, St. Catherine University, St. Paul, Minnesota, USA
| | - Sylvia S Lee
- Office of Research and Development, U.S. Environmental Protection Agency, Washington, District of Columbia, USA
| | - Daniel L Clemans
- Department of Biology, Eastern Michigan University, Ypsilanti, Michigan, USA
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15
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Karcher DB, Roth F, Carvalho S, El-Khaled YC, Tilstra A, Kürten B, Struck U, Jones BH, Wild C. Nitrogen eutrophication particularly promotes turf algae in coral reefs of the central Red Sea. PeerJ 2020; 8:e8737. [PMID: 32274261 PMCID: PMC7130110 DOI: 10.7717/peerj.8737] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Accepted: 02/12/2020] [Indexed: 11/20/2022] Open
Abstract
While various sources increasingly release nutrients to the Red Sea, knowledge about their effects on benthic coral reef communities is scarce. Here, we provide the first comparative assessment of the response of all major benthic groups (hard and soft corals, turf algae and reef sands—together accounting for 80% of the benthic reef community) to in-situ eutrophication in a central Red Sea coral reef. For 8 weeks, dissolved inorganic nitrogen (DIN) concentrations were experimentally increased 3-fold above environmental background concentrations around natural benthic reef communities using a slow release fertilizer with 15% total nitrogen (N) content. We investigated which major functional groups took up the available N, and how this changed organic carbon (Corg) and N contents using elemental and stable isotope measurements. Findings revealed that hard corals (in their tissue), soft corals and turf algae incorporated fertilizer N as indicated by significant increases in δ15N by 8%, 27% and 28%, respectively. Among the investigated groups, Corg content significantly increased in sediments (+24%) and in turf algae (+33%). Altogether, this suggests that among the benthic organisms only turf algae were limited by N availability and thus benefited most from N addition. Thereby, based on higher Corg content, turf algae potentially gained competitive advantage over, for example, hard corals. Local management should, thus, particularly address DIN eutrophication by coastal development and consider the role of turf algae as potential bioindicator for eutrophication.
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Affiliation(s)
- Denis B Karcher
- Marine Ecology Department, Faculty of Biology and Chemistry, University of Bremen, Bremen, Germany
| | - Florian Roth
- Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia.,Baltic Sea Centre, Stockholm University, Stockholm, Sweden.,Tvärminne Zoological Station, Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | - Susana Carvalho
- Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Yusuf C El-Khaled
- Marine Ecology Department, Faculty of Biology and Chemistry, University of Bremen, Bremen, Germany
| | - Arjen Tilstra
- Marine Ecology Department, Faculty of Biology and Chemistry, University of Bremen, Bremen, Germany
| | - Benjamin Kürten
- Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia.,Project Management Jülich, Jülich Research Centre, Rostock, Germany
| | - Ulrich Struck
- Museum für Naturkunde, Leibniz Institute for Evolution and Biodiversity Science, Berlin, Germany.,Department of Earth Sciences, Freie Universität Berlin, Berlin, Germany
| | - Burton H Jones
- Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Christian Wild
- Marine Ecology Department, Faculty of Biology and Chemistry, University of Bremen, Bremen, Germany
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16
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Tsuboi M, Kopperud BT, Syrowatka C, Grabowski M, Voje KL, Pélabon C, Hansen TF. Measuring Complex Morphological Traits with 3D Photogrammetry: A Case Study with Deer Antlers. Evol Biol 2020. [DOI: 10.1007/s11692-020-09496-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
AbstractThe increasing availability of 3D-imaging technology provides new opportunities for measuring morphology. Photogrammetry enables easy 3D-data acquisition compared to conventional methods and here we assess its accuracy for measuring the size of deer antlers, a complex morphological structure. Using a proprietary photogrammetry software, we generated 3D images of antlers for 92 individuals from 29 species of cervids that vary widely in antler size and shape and used these to measure antler volume. By repeating the process, we found that the relative error averaged 8.5% of object size. Errors in converting arbitrary voxel units into real volumetric units accounted for 70% of the measurement variance and can therefore be reduced by replicating the conversion. We applied the method to clay models of known volume and found no indication of bias. The estimation was robust against variation in imaging device, distance and operator, but approximately 40 images per specimen were necessary to achieve good precision. We used the method to show that conventional measures of main-beam length are relatively poor estimators of antler volume. Using loose antlers of known weight, we also showed that the volume may be a relatively poor predictor of antler weight due to variation in bone density across species. We conclude that photogrammetry can be an efficient and accurate tool for measuring antlers, and likely many other complex morphological traits.
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