1
|
Clausing RJ, Falace A, De Le Fuente G, Della Torre C, Chiantore M, Asnaghi V. Ex-situ restoration of the Mediterranean forest-forming macroalga Ericaria amentacea: Optimizing growth in culture may not be the key to growth in the field. MARINE ENVIRONMENTAL RESEARCH 2024; 202:106718. [PMID: 39232470 DOI: 10.1016/j.marenvres.2024.106718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2024] [Revised: 08/11/2024] [Accepted: 08/29/2024] [Indexed: 09/06/2024]
Abstract
Evidence of local and regional declines in the canopy-forming alga Ericaria amentacea, a foundation species of diverse marine forest communities on exposed Mediterranean coasts, have spurred restoration efforts focused on sustainable ex-situ techniques. The need to balance the costs of culture maintenance and the susceptibility of early life stages to stressors in the native habitat, including rapid, often extreme shifts in temperature, hydrodynamics and nutrient availability, have driven current efforts to create a culture environment that primes seedlings for outplant, increasing their resilience rather than maximizing growth. We tested the effects of 1) higher culture temperature (25 °C) combined with wave simulation and 2) reduced nutrient loads (10% of standard protocol) with wave simulation on post-culture and post-outplant outcomes relative to optimal growth conditions in established protocols (20 °C, no waves, high-nutrient culture medium). While increased temperature and water motion negatively affected seedling growth in culture, and higher nutrients caused oxidative stress likely associated with enhanced epiphyte overgrowth, these effects were not clearly translated into patterns of long-term growth in the field. Instead, survival in the initial days post-outplant appeared to be the bottleneck for restoration potential, where substrates with persisting seedlings at one month were generally found with flourishing juveniles at four months. Larger clumps of seedlings, in turn, were strongly associated with both initial survival and future growth. These results underscore the importance of the zygote settlement phase to establish high seedling densities, which may be optimized by phenological monitoring of the donor population. They also suggest that less-controlled, more environmentally-realistic culture conditions involving the introduction of mild stress may enhance the survival of early life stages of E. amentacea during the transition to the native environment, providing a means to simultaneously reduce human resource costs in culture and move toward scaling up.
Collapse
Affiliation(s)
- Rachel J Clausing
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, CA, USA; Department of Earth, Environment and Life Sciences, University of Genoa, Genoa, Italy.
| | - Annalisa Falace
- Department of Life Sciences, University of Trieste, Trieste, Italy
| | - Gina De Le Fuente
- Department of Earth, Environment and Life Sciences, University of Genoa, Genoa, Italy
| | | | - Mariachiara Chiantore
- Department of Earth, Environment and Life Sciences, University of Genoa, Genoa, Italy; National Biodiversity Future Center, Palermo, Italy
| | - Valentina Asnaghi
- Department of Earth, Environment and Life Sciences, University of Genoa, Genoa, Italy; National Biodiversity Future Center, Palermo, Italy
| |
Collapse
|
2
|
Rearte TA, Celis-Pla PSM, Abdala-Díaz R, Castro-Varela P, Marsili SN, García C, Cerón-García MC, Figueroa FL. Increase in polyunsaturated fatty acids and carotenoid accumulation in the microalga Golenkinia brevispicula (Chlorophyceae) by manipulating spectral irradiance and salinity. Biotechnol Bioeng 2024. [PMID: 39183489 DOI: 10.1002/bit.28831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2024] [Revised: 08/02/2024] [Accepted: 08/10/2024] [Indexed: 08/27/2024]
Abstract
Microalgal biotechnology offers a promising platform for the sustainable production of diverse renewable bioactive compounds. The key distinction from other microbial bioprocesses lies in the critical role that light plays in cultures, as it serves as a source of environmental information to control metabolic processes. Therefore, we can use these criteria to design a bioprocess that aims to stimulate the accumulation of target molecules by controlling light exposure. We study the effect on biochemical and photobiological responses of Golenkinia brevispicula FAUBA-3 to the exposition of different spectral irradiances (specifically, high-fluence PAR of narrow yellow spectrum complemented with low intensity of monochromatic radiations of red, blue, and UV-A) under prestress and salinity stress conditions. High light (HL) intensity coupled to salinity stress affected the photosynthetic activity and photoprotection mechanisms as shown by maximal quantum yield (Fv/Fm) and non-photochemical quenching (NPQmax) reduction, respectively. HL treatments combined with the proper dose of UV-A radiation under salinity stress induced the highest carotenoid content (2.75 mg g dry weight [DW]- 1) composed mainly of lutein and β-carotene, and the highest lipid accumulation (35.3% DW) with the highest polyunsaturated fatty acid content (alpha-linolenic acid (C18:3) and linoleic acid (C18:2)). Our study can guide the strategies for commercial indoor production of G. brevispicula for high-value metabolites.
Collapse
Affiliation(s)
- T A Rearte
- Cátedra de Química Inorgánica y Analítica, Departamento de Recursos Naturales y Ambiente, Facultad de Agronomía, Universidad de Buenos Aires, CABA, Buenos Aires, Argentina
- Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Buenos Aires, Argentina
| | - P S M Celis-Pla
- Laboratory of Aquatic Environmental Research (LACER)/HUB-AMBIENTAL UPLA, Playa Ancha University, Valparaíso, Chile
- Departamento de Ciencias y Geografía, Facultad de Ciencias Naturales y Exactas, Universidad de Playa Ancha, Valparaíso, Chile
| | - R Abdala-Díaz
- Universidad de Málaga, Instituto Andaluz de Biotecnología y Desarrollo Azul (IBYDA), Centro Experimental Grice Hutchinson, Málaga, Spain
| | - P Castro-Varela
- Departamento de Botánica, Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Concepción, Chile
| | - S N Marsili
- Cátedra de Química Inorgánica y Analítica, Departamento de Recursos Naturales y Ambiente, Facultad de Agronomía, Universidad de Buenos Aires, CABA, Buenos Aires, Argentina
- Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Buenos Aires, Argentina
| | - C García
- Universidad Nacional de Cuyo, Mendoza, Argentina
| | - M C Cerón-García
- Department of Chemical Engineering and Research Centre CIAIMBITAL, University of Almería, Almería, Spain
| | - F L Figueroa
- Universidad de Málaga, Instituto Andaluz de Biotecnología y Desarrollo Azul (IBYDA), Centro Experimental Grice Hutchinson, Málaga, Spain
| |
Collapse
|
3
|
Muguerza N, Quintano E, Díez I, García-Baquero G, Figueroa FL, Vega J, Gorostiaga JM. Split-plot marine experiment to assess ecophysiological responses of Gelidium corneum assemblages. MARINE ENVIRONMENTAL RESEARCH 2024; 194:106310. [PMID: 38150788 DOI: 10.1016/j.marenvres.2023.106310] [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: 09/30/2023] [Revised: 11/27/2023] [Accepted: 12/15/2023] [Indexed: 12/29/2023]
Abstract
Canopy-forming macroalgae are facing large declines due to climate change worldwide. The foundation species Gelidium corneum (Hudson) J.V. Lamouroux has shown a long-term decline in the Southeastern Bay of Biscay. We conducted an in situ experiment to investigate the combined effect of solar radiation and nutrient availability on the photosynthetic acclimation and growth of this macrophyte, and on the species richness and diversity of the assemblages that it forms. Photochemical stress in G. corneum was found to be greater at the end of the study, probably as a result of a prolonged exposure to high irradiance (PAR and UVR) and due to high temperatures during summer. We found an acclimation of G. corneum specimens to summer light and thermal conditions through dynamic/reversible photoinhibition and a decrease in photosynthetic efficiency. Nutrients may also have had a positive effect in dealing with the negative effects of these stressors. Under ongoing global climate change and projections for the future, further research will be needed to better understand the effects not only on canopy forming species but also on the whole community and thus on the functioning of the ecosystem.
Collapse
Affiliation(s)
- N Muguerza
- Laboratory of Botany, Department of Plant Biology and Ecology, Fac. of Science and Technology & Research Centre for Experimental Marine Biology and Biotechnology PIE-UPV/EHU, University of the Basque Country (UPV/EHU), PO Box 644, 48080, Bilbao, Spain.
| | - E Quintano
- Laboratory of Botany, Department of Plant Biology and Ecology, Fac. of Science and Technology & Research Centre for Experimental Marine Biology and Biotechnology PIE-UPV/EHU, University of the Basque Country (UPV/EHU), PO Box 644, 48080, Bilbao, Spain
| | - I Díez
- Laboratory of Botany, Department of Plant Biology and Ecology, Fac. of Science and Technology & Research Centre for Experimental Marine Biology and Biotechnology PIE-UPV/EHU, University of the Basque Country (UPV/EHU), PO Box 644, 48080, Bilbao, Spain
| | - G García-Baquero
- Department of Botany and Plant Physiology, Faculty of Pharmacy, University of Salamanca, Avda Licenciado Méndez Nieto s/n, 37007, Salamanca, Spain; Biodonostia Health Research Institute, Group of Environmental Epidemiology and Child Development, Paseo Doctor Begiristain s/n, 20014, Donostia- San Sebastián, Spain
| | - F L Figueroa
- Universidad de Málaga, Instituto Andaluz de Biotecnología y Desarrollo Azul (IBYDA), Centro Experimental Grice Hutchinson, Lomas de San Julián, 2, 29004, Malaga, Spain
| | - J Vega
- Universidad de Málaga, Instituto Andaluz de Biotecnología y Desarrollo Azul (IBYDA), Centro Experimental Grice Hutchinson, Lomas de San Julián, 2, 29004, Malaga, Spain
| | - J M Gorostiaga
- Laboratory of Botany, Department of Plant Biology and Ecology, Fac. of Science and Technology & Research Centre for Experimental Marine Biology and Biotechnology PIE-UPV/EHU, University of the Basque Country (UPV/EHU), PO Box 644, 48080, Bilbao, Spain
| |
Collapse
|
4
|
Kytinou E, Issaris Y, Sini M, Salomidi M, Katsanevakis S. ECOfast - An integrative ecological evaluation index for an ecosystem-based assessment of shallow rocky reefs. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 344:118323. [PMID: 37354588 DOI: 10.1016/j.jenvman.2023.118323] [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: 01/23/2023] [Revised: 05/29/2023] [Accepted: 06/03/2023] [Indexed: 06/26/2023]
Abstract
The degradation of marine ecosystems is a growing concern worldwide, emphasizing the need for efficient tools to assess their ecological status. Herein, a novel ecosystem-based ecological evaluation index of shallow rocky reefs is introduced and tested in the Aegean and Ionian Seas (NE Mediterranean). The index focuses on a specific set of pre-selected species, including habitat-forming, key, commercially important, and non-indigenous species, across a wide range of trophic levels (1.00-4.53). Data acquisition is conducted through rapid non-destructive SCUBA diving surveys to assess all macroscopic food web components (macroalgae, invertebrates, and fish). Two versions of the index, ECOfast and ECOfast-NIS, were developed, each applying a different approach to account for the impact of non-indigenous species. In our case study, the correlations between the two versions of the index and sea surface temperature, protection status, occurrence of carnivorous fish, and non-indigenous herbivores were assessed through generalized additive models (GAMs). The assessment assigned 93% (ECOfast) or 96% (ECOfast-NIS) of the sites to a moderate to bad ecological status, indicating an alarming situation in the shallow rocky reefs of the NE Mediterranean. Sites evaluated as poor or bad were characterized by extensive coverage of ephemeral macroalgae, absence or minimal presence of large indigenous carnivorous fish, and complete absence of one to three out of five invertebrate functional trophic groups. The community composition of macroalgae, herbivorous species, and carnivorous fishes differed between the 5 m and 15 m depth zones. Surface temperature and carnivorous fish occurrence were the most important tested predictors of the ecological status of shallow rocky reefs. The best GAMs showed that the ECOfast score declined with sea surface temperature and increased with the occurrence of carnivorous fish; ECOfast-NIS declined with sea surface temperature and the occurrence of non-indigenous fish and increased with the occurrence of carnivorous fish. The non-destructive and integrative nature of this approach, its speed of data acquisition and analysis, and its capacity to account for highly mobile predatory fish and non-indigenous species render the ECOfast index a novel, robust, and valuable tool for assessing the ecological status of shallow rocky reefs.
Collapse
Affiliation(s)
- Eleni Kytinou
- Department of Marine Sciences, University of the Aegean, Lofos Panepistimiou, 81100, Mytilene, Greece; Institute of Oceanography, Hellenic Centre for Marine Research, 46.7 km Athens Sounio Ave., 19013, Anavyssos, Greece.
| | - Yiannis Issaris
- Institute of Oceanography, Hellenic Centre for Marine Research, 46.7 km Athens Sounio Ave., 19013, Anavyssos, Greece
| | - Maria Sini
- Department of Marine Sciences, University of the Aegean, Lofos Panepistimiou, 81100, Mytilene, Greece
| | - Maria Salomidi
- Institute of Oceanography, Hellenic Centre for Marine Research, 46.7 km Athens Sounio Ave., 19013, Anavyssos, Greece
| | - Stelios Katsanevakis
- Department of Marine Sciences, University of the Aegean, Lofos Panepistimiou, 81100, Mytilene, Greece
| |
Collapse
|
5
|
Celis-Plá PSM, Trabal A, Navarrete C, Troncoso M, Moenne F, Zúñiga A, Figueroa FL, Sáez CA. Daily changes on seasonal ecophysiological responses of the intertidal brown macroalga Lessonia spicata: Implications of climate change. FRONTIERS IN PLANT SCIENCE 2022; 13:941061. [PMID: 36247624 PMCID: PMC9554264 DOI: 10.3389/fpls.2022.941061] [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: 05/11/2022] [Accepted: 09/01/2022] [Indexed: 06/16/2023]
Abstract
Global climate change is expected to have detrimental effects on coastal ecosystems, with impacts observable at the local and regional levels, depending on factors such as light, temperature, and nutrients. Shifts in dominance between primary producers that can capitalize on carbon availability for photosynthesis will have knock-on effects on marine ecosystems, affecting their ecophysiological responses and biological processes. Here, we study the ecophysiological vulnerability, photoacclimation capacity, and tolerance responses as ecophysiological responses of the intertidal kelp Lessonia spicata (Phaeophyceae, Laminariales) during a year through different seasons (autumn, winter, spring, and summer) in the Pacific Ocean (central Chile). Six different daily cycle experiments were carried out within each season. A battery of different biochemical assays associated with antioxidant responses and in-vivo chlorophyll a fluorescence parameter showed that during spring and summer, there was an increase in photosynthetic capacity in the macroalgae, although their responses varied depending on light and nutrient availability in the course of the year. Lessonia spicata showed maximal photosynthesis and a similar photoinhibition pattern in summer compared to the other seasons, and the contents of nitrate and phosphorous in seawater were less in winter. Thus, high irradiance during spring and summer displayed a higher maximal electron transport rate (ETRmax), irradiance of saturation (Ek), non-photochemical quenching (NPQmax), nitrogen and carbon contents, and photoprotector compound levels. Antioxidant activity increased also in summer, the seasonal period with the highest oxidative stress conditions, i.e., the highest level of hydrogen peroxide (H2O2). In contrast, under low irradiance, i.e., wintertime conditions, L. spicata demonstrated lower concentrations of the photosynthetic pigments such as chlorophyll a and carotenoids. Our study suggests that macroalgae that are subjected to increased irradiance and water temperature under lower nutrient availability mediated by seasonal changes (expected to worsen under climate change) respond with higher values of productivity, pigment contents, and photoprotective compounds. Thus, our findings strengthen the available evidence to predict that algae in the order Laminariales, specifically L. spicata (kelp), could better proliferate, with lower vulnerability and greater acclimation, than other marine species subject to future expected conditions associated with climate change.
Collapse
Affiliation(s)
- Paula S. M. Celis-Plá
- Laboratory of Aquatic Environmental Research (LACER), Centro de Estudios Avanzados (CEA)/HUB Ambiental UPLA, Universidad de Playa Ancha, Valparaíso, Chile
| | - Andres Trabal
- Laboratory of Aquatic Environmental Research (LACER), Centro de Estudios Avanzados (CEA)/HUB Ambiental UPLA, Universidad de Playa Ancha, Valparaíso, Chile
- Escuela de Ciencias Agrarias y Veterinarias, Universidad de Viña del Mar, Viña del Mar, Chile
| | - Camilo Navarrete
- Laboratory of Aquatic Environmental Research (LACER), Centro de Estudios Avanzados (CEA)/HUB Ambiental UPLA, Universidad de Playa Ancha, Valparaíso, Chile
- Doctorado Interdisciplinario en Ciencias Ambientales, Facultad de Ciencias Naturales y Exactas, Universidad de Playa Ancha, Valparaíso, Chile
| | - Macarena Troncoso
- Laboratory of Aquatic Environmental Research (LACER), Centro de Estudios Avanzados (CEA)/HUB Ambiental UPLA, Universidad de Playa Ancha, Valparaíso, Chile
- Doctorado Interdisciplinario en Ciencias Ambientales, Facultad de Ciencias Naturales y Exactas, Universidad de Playa Ancha, Valparaíso, Chile
| | - Fabiola Moenne
- Laboratory of Aquatic Environmental Research (LACER), Centro de Estudios Avanzados (CEA)/HUB Ambiental UPLA, Universidad de Playa Ancha, Valparaíso, Chile
| | - Antonio Zúñiga
- Laboratory of Aquatic Environmental Research (LACER), Centro de Estudios Avanzados (CEA)/HUB Ambiental UPLA, Universidad de Playa Ancha, Valparaíso, Chile
| | - Félix L. Figueroa
- Ecology Department, Institute of Blue Biotechnology and Development (IBYDA), University of Malaga, Malaga, Spain
| | - Claudio A. Sáez
- Laboratory of Aquatic Environmental Research (LACER), Centro de Estudios Avanzados (CEA)/HUB Ambiental UPLA, Universidad de Playa Ancha, Valparaíso, Chile
- Departamento de Ciencias del Mar y Biología Aplicada, Facultad de Ciencias, Universidad de Alicante, Alicante, Spain
| |
Collapse
|
6
|
Chemello S, Signa G, Mazzola A, Ribeiro Pereira T, Sousa Pinto I, Vizzini S. Limited Stress Response to Transplantation in the Mediterranean Macroalga Ericaria amentacea, a Key Species for Marine Forest Restoration. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:12253. [PMID: 36231556 PMCID: PMC9566098 DOI: 10.3390/ijerph191912253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 09/19/2022] [Accepted: 09/20/2022] [Indexed: 06/16/2023]
Abstract
In the Mediterranean Sea, brown macroalgae represent the dominant species in intertidal and subtidal habitats. Despite conservation efforts, these canopy-forming species showed a dramatic decline, highlighting the urge for active intervention to regenerate self-sustaining populations. For this reason, the restoration of macroalgae forests through transplantation has been recognized as a promising approach. However, the potential stress caused by the handling of thalli has never been assessed. Here, we used a manipulative approach to assess the transplant-induced stress in the Mediterranean Ericaria amentacea, through the analysis of biochemical proxies, i.e., phenolic compounds, lipids, and fatty acids in both transplanted and natural macroalgae over time. The results showed that seasonal environmental variability had an important effect on the biochemical composition of macroalgae, suggesting the occurrence of acclimation responses to summer increased temperature and light irradiance. Transplant-induced stress appears to have only amplified the biochemical response, probably due to increased sensitivity of the macroalgae already subjected to mechanical and osmotic stress (e.g., handling, wounding, desiccation). The ability of E. amentacea to cope with both environmental and transplant-induced stress highlights the high plasticity of the species studied, as well as the suitability of transplantation of adult thalli to restore E. amentacea beds.
Collapse
Affiliation(s)
- Silvia Chemello
- Department of Earth and Marine Sciences (DiSTeM), University of Palermo, 90123 Palermo, Italy
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), University of Porto, 4450-208 Matosinhos, Portugal
| | - Geraldina Signa
- Department of Earth and Marine Sciences (DiSTeM), University of Palermo, 90123 Palermo, Italy
- Consorzio Nazionale Interuniversitario per le Scienze del Mare (CoNISMa), 00196 Rome, Italy
| | - Antonio Mazzola
- Department of Earth and Marine Sciences (DiSTeM), University of Palermo, 90123 Palermo, Italy
- Consorzio Nazionale Interuniversitario per le Scienze del Mare (CoNISMa), 00196 Rome, Italy
| | - Tania Ribeiro Pereira
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), University of Porto, 4450-208 Matosinhos, Portugal
| | - Isabel Sousa Pinto
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), University of Porto, 4450-208 Matosinhos, Portugal
| | - Salvatrice Vizzini
- Department of Earth and Marine Sciences (DiSTeM), University of Palermo, 90123 Palermo, Italy
- Consorzio Nazionale Interuniversitario per le Scienze del Mare (CoNISMa), 00196 Rome, Italy
| |
Collapse
|
7
|
De La Fuente G, Pinteus S, Silva J, Alves C, Pedrosa R. Antioxidant and antimicrobial potential of six Fucoids from the Mediterranean Sea and the Atlantic Ocean. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2022; 102:5568-5575. [PMID: 35439330 DOI: 10.1002/jsfa.11944] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 04/04/2022] [Accepted: 04/19/2022] [Indexed: 06/14/2023]
Abstract
BACKGROUD In recent years, research on the bioactive properties of macroalgae has increased, due to the great interest in exploring new products that can contribute to improve human health and wellbeing. In the present study, the antioxidant and antimicrobial potential of six different brown algae of the Fucales order were evaluated, namely Ericaria selaginoides, Ericaria amentacea, Gongolaria baccata, Gongolaria usneoides, Cystoseira compressa and Sargassum vulgare (collected along the Mediterranean and Atlantic coasts). The antioxidant capacity was measured by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, the oxygen radical absorbent capacity (ORAC) and the ferric reducing antioxidant power (FRAP) and were related to the total phenolic content (TPC). The antimicrobial activity was evaluated measuring the growth inhibition of Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans. RESULTS The highest antioxidant capacity was obtained for Ericaria selaginoides revealing the highest capacity to scavenge DPPH radical [half maximal effective concentration (EC50 ) = 27.02 μg mL-1 ], highest FRAP (1761.19 μmol FeSO4 equivalents g-1 extract), high ORAC (138.92 μmol TE g-1 extract), alongside to its high TPC (121.5 GAE g-1 extract). This species also reported the highest antimicrobial capacity against Staphylococcus aureus [half maximal inhibitory concentration (IC50 ) = 268 μg mL-1 ]. CONCLUSIONS Among all studied seaweed, Ericaria selaginoides reveals the highest antioxidant and antimicrobial activities, and thus should be explored as a natural food additive and/or functional ingredient. © 2022 Society of Chemical Industry.
Collapse
Affiliation(s)
- Gina De La Fuente
- DiSTAV - Dipartimento di Scienze della Terra, dell'Ambiente e della Vita, Università degli Studi di Genova, Genoa, Italy
| | - Susete Pinteus
- MARE - Marine and Environmental Sciences Center, Polytechnic of Leiria, Peniche, Portugal
| | - Joana Silva
- MARE - Marine and Environmental Sciences Center, Polytechnic of Leiria, Peniche, Portugal
| | - Celso Alves
- MARE - Marine and Environmental Sciences Center, Polytechnic of Leiria, Peniche, Portugal
| | - Rui Pedrosa
- MARE - Marine and Environmental Sciences Center, ESTM, Polytechnic of Leiria, Peniche, Portugal
| |
Collapse
|
8
|
Elevated CO2 influences competition for growth, photosynthetic performance and biochemical composition in Neopyropia yezoensis and Ulva prolifera. ALGAL RES 2021. [DOI: 10.1016/j.algal.2021.102313] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
9
|
Figueroa FL, Bonomi-Barufi J, Celis-Plá PSM, Nitschke U, Arenas F, Connan S, Abreu MH, Malta EJ, Conde-Álvarez R, Chow F, Mata MT, Meyerhoff O, Robledo D, Stengel DB. Short-term effects of increased CO2, nitrate and temperature on photosynthetic activity in Ulva rigida (Chlorophyta) estimated by different pulse amplitude modulated fluorometers and oxygen evolution. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:491-509. [PMID: 33064811 DOI: 10.1093/jxb/eraa473] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Accepted: 10/13/2020] [Indexed: 05/16/2023]
Abstract
Short-term effects of pCO2 (700-380 ppm; High carbon (HC) and Low carbon (LC), respectively) and nitrate content (50-5 µM; High nitrogen (HN) and Low nitrogen (LN), respectively on photosynthesis were investigated in Ulva rigida (Chlorophyta) under solar radiation (in-situ) and in the laboratory under artificial light (ex-situ). After six days of incubation at ambient temperature (AT), algae were subjected to a 4 °C temperature increase (AT+4 °C) for 3 d. Both in-situ and ex-situ maximal electron transport rate (ETRmax) and in situ gross photosynthesis (GP), measured by O2 evolution, presented highest values under HCHN, and lowest under HCLN, across all measuring systems. Maximal quantum yield (Fv/Fm), and ETRmax of photosystem (PS) II [ETR(II)max] and PSI [ETR(I)max], decreased under HCLN at AT+4 °C. Ex situ ETR was higher than in situ ETR. At noon, Fv/Fm decreased (indicating photoinhibition), whereas ETR(II)max and maximal non-photochemical quenching (NPQmax) increased. ETR(II)max decreased under AT+ 4 °C in contrast to Fv/Fm, photosynthetic efficiency (α ETR) and saturated irradiance (EK). Thus, U. rigida exhibited a decrease in photosynthesis under acidification, changing LN, and AT+4 °C. These results emphasize the importance of studying the interaction between environmental parameters using in-situ versus ex-situ conditions, when aiming to evaluate the impact of global change on marine macroalgae.
Collapse
Affiliation(s)
- Felix L Figueroa
- Malaga University. Institute of Blue Biotechnology and Development (IBYDA), Ecology department, Faculty of Sciences, Campus universitario de Teatinos s/n, Malaga, Spain
| | - Jose Bonomi-Barufi
- Botany department, Federal University of Santa Catarina. Campus Trindade s/n, Florianópolis, SC, Brazil
| | - Paula S M Celis-Plá
- Laboratory of Coastal Environmental Research, Center of Advances Studies. University of Playa Ancha. Traslaviña, Viña del Mar, Chile
- Hub Ambiental UPLA, Vicerrectoría de Investigación, Postgrado e Innovación, Universidad de Playa Ancha, Valparaíso, Chile
| | - Udo Nitschke
- Botany and Plant Science, School of Natural Sciences, Ryan Institute for Environmental, Marine and Energy Research, National University of Ireland Galway, Galway, Ireland
| | - Francisco Arenas
- CIIMAR - Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Rua dos Bragas, Porto, Portugal
| | - Solene Connan
- CNRS, GEPEA, UMR6144, Boulevard de l'Université, CRTT BP, Saint Nazaire Cedex, France
- Univ Brest, CNRS, IRD, Ifremer, Lemar, Plouzane, France
| | | | - Erik-J Malta
- Centro IFAPA Agua del Pino, Crtra. El Rómpido - Punta Umbría, Cartaya (Huelva), Spain
| | - Rafael Conde-Álvarez
- Malaga University. Institute of Blue Biotechnology and Development (IBYDA), Ecology department, Faculty of Sciences, Campus universitario de Teatinos s/n, Malaga, Spain
| | - Fungyi Chow
- Department of Botany, University of São Paulo, Rua do Matão, São Paulo, SP, Brazil
| | - Maria Teresa Mata
- Centro de Bioinnovación Antofagasta (CBIA), Faculty of Marine Sciences and Biological Resources, Antofagasta University, Antofagasta, Chile
| | - O Meyerhoff
- Heinz Walz GmbH Eichenring 6 - 91090 Effeltrich, Germany
| | - Daniel Robledo
- CIVESTAV-IPN, Unidad Mérida Km6 Antigua Carretera a Progreso Apartado Postal Cordemex, Mérida, Yucatán, México
| | - Dagmar B Stengel
- Botany and Plant Science, School of Natural Sciences, Ryan Institute for Environmental, Marine and Energy Research, National University of Ireland Galway, Galway, Ireland
| |
Collapse
|
10
|
Celis-Plá PSM, Kappes JL, Figueroa FL, Pereda SV, Villegas K, Altamirano R, Hernández-González MC, Buschmann AH. Solar Radiation as an Isolated Environmental Factor in an Experimental Mesocosm Approach for Studying Photosynthetic Acclimation of Macrocystis pyrifera (Ochrophyta). FRONTIERS IN PLANT SCIENCE 2021; 12:622150. [PMID: 34276713 PMCID: PMC8283697 DOI: 10.3389/fpls.2021.622150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Accepted: 06/04/2021] [Indexed: 05/17/2023]
Abstract
Solar radiation effects on the ecophysiology and biochemical responses of the brown macroalga Macrocystis pyrifera (L.) C. Agardh were evaluated using a mesocosm approach in Southern Chile. Treatments with different radiation attenuations were simulated with three vertical attenuation coefficients: (1) total (Kd = 0.8 m-1), (2) attenuated (Kd = 1.2 m-1), and (3) low (Kd = 1.6 m-1) radiation levels. Nutrient concentration and temperature did not show differences under the three light conditions. Photosynthetic activity was estimated by in vivo chlorophyll a (Chla) fluorescence under the three light treatments as an isolated physical factor in both in situ solar radiation in the field. This was achieved using a pulse amplitude-modulated (PAM) fluorometera-Diving PAM (in situ). Photosynthetic activity and biochemical composition were measured in winter during two daily cycles (1DC and 2DC) in different parts of the thalli of the plant: (1) canopy zone, (2) middle zone, and (3) down zone, associated with different depths in the mesocosm system. Nevertheless, the in situ electron transport rate (ETR in situ ) was higher in the exposed thalli of the canopy zone, independent of the light treatment conditions. The concentration of phenolic compounds (PC) increases in the down zone in the first daily cycle, and it was higher in the middle zone in the second daily cycle. The Chla increased in the morning time under total and attenuated radiation in the first daily cycle. Solar radiation increasing at midday prompted the photoinhibition of photosynthesis in the canopy zone but also an increase in productivity and phenol content. Therefore, light attenuation in the water column drove key differences in the photo-physiological responses of M. pyrifera, with the highest productivity occurring in thalli positioned in the canopy zone when exposed to solar irradiance.
Collapse
Affiliation(s)
- Paula S. M. Celis-Plá
- Laboratory of Aquatic Environmental Research (LACER), Centro de Estudios Avanzados, Universidad de Playa Ancha, Viña del Mar, Chile
- HUB Ambiental Universidad de Playa Ancha (UPLA), Vicerrectoría de Investigación Postgrado e Innovación, Universidad de Playa Ancha, Valparaíso, Chile
- Paula S. M. Celis-Plá
| | - José Luis Kappes
- Centro de Investigación y Desarrollo de Ambientes y Recursos Costeros (Centro i-mar) and Centro de Biotecnología y Bioingenería (CeBiB), Universidad de Los Lagos, Puerto Montt, Chile
| | - Félix L. Figueroa
- Department of Ecology and Geology, Faculty of Sciences, Institute of Biotechnology and Blue Development (IBYDA), University of Malaga, Malaga, Spain
| | - Sandra V. Pereda
- Centro de Investigación y Desarrollo de Ambientes y Recursos Costeros (Centro i-mar) and Centro de Biotecnología y Bioingenería (CeBiB), Universidad de Los Lagos, Puerto Montt, Chile
| | - Karina Villegas
- Centro de Investigación y Desarrollo de Ambientes y Recursos Costeros (Centro i-mar) and Centro de Biotecnología y Bioingenería (CeBiB), Universidad de Los Lagos, Puerto Montt, Chile
| | - Robinson Altamirano
- Centro de Investigación y Desarrollo de Ambientes y Recursos Costeros (Centro i-mar) and Centro de Biotecnología y Bioingenería (CeBiB), Universidad de Los Lagos, Puerto Montt, Chile
| | - María Carmen Hernández-González
- Centro de Investigación y Desarrollo de Ambientes y Recursos Costeros (Centro i-mar) and Centro de Biotecnología y Bioingenería (CeBiB), Universidad de Los Lagos, Puerto Montt, Chile
| | - Alejandro H. Buschmann
- Centro de Investigación y Desarrollo de Ambientes y Recursos Costeros (Centro i-mar) and Centro de Biotecnología y Bioingenería (CeBiB), Universidad de Los Lagos, Puerto Montt, Chile
- *Correspondence: Alejandro H. Buschmann
| |
Collapse
|
11
|
Ji Y, Gao K. Effects of climate change factors on marine macroalgae: A review. ADVANCES IN MARINE BIOLOGY 2020; 88:91-136. [PMID: 34119047 DOI: 10.1016/bs.amb.2020.11.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Marine macroalgae, the main primary producers in coastal waters, play important roles in the fishery industry and global carbon cycles. With progressive ocean global changes, however, they are increasingly exposed to enhanced levels of multiple environmental drivers, such as ocean acidification, warming, heatwaves, UV radiation and deoxygenation. While most macroalgae have developed physiological strategies against variations of these drivers, their eco-physiological responses to each or combinations of the drivers differ spatiotemporally and species-specifically. Many freshwater macroalgae are tolerant of pH drop and its diel fluctuations and capable of acclimating to changes in carbonate chemistry. However, calcifying species, such as coralline algae, are very sensitive to acidification of seawater, which reduces their calcification, and additionally, temperature rise and UV further decrease their physiological performance. Except for these calcifying species, both economically important and harmful macroalgae can benefit from elevated CO2 concentrations and moderate temperature rise, which might be responsible for increasing events of harmful macroalgal blooms including green macroalgal blooms caused by Ulva spp. and golden tides caused by Sargassum spp. Upper intertidal macroalgae, especially those tolerant of dehydration during low tide, increase their photosynthesis under elevated CO2 concentrations during the initial dehydration period, however, these species might be endangered by heatwaves, which can expose them to high temperature levels above their thermal windows' upper limit. On the other hand, since macroalgae are distributed in shallow waters, they are inevitably exposed to solar UV radiation. The effects of UV radiation, depending on weather conditions and species, can be harmful as well as beneficial to many species. Moderate levels of UV-A (315-400nm) can enhance photosynthesis of green, brown and red algae, while UV-B (280-315nm) mainly show inhibitory impacts. Although little has been documented on the combined effects of elevated CO2, temperature or heatwaves with UV radiation, exposures to heatwaves during midday under high levels of UV radiation can be detrimental to most species, especially to their microscopic stages which are less tolerant of climate change induced stress. In parallel, reduced availability of dissolved O2 in coastal water along with eutrophication might favour the macroalgae's carboxylation process by suppressing their oxygenation or photorespiration. In this review, we analyse effects of climate change-relevant drivers individually and/or jointly on different macroalgal groups and different life cycle stages based on the literatures surveyed, and provide perspectives for future studies.
Collapse
Affiliation(s)
- Yan Ji
- State Key Laboratory of Marine Environmental Science, Xiamen University/College of Ocean and Earth Sciences, Xiamen, China; School of Biological & Chemical Engineering, Qingdao Technical College, Qingdao, China
| | - Kunshan Gao
- State Key Laboratory of Marine Environmental Science, Xiamen University/College of Ocean and Earth Sciences, Xiamen, China; Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Jiangsu Ocean University, Lianyungang, China.
| |
Collapse
|
12
|
Chu Y, Liu Y, Li J, Gong Q. Effects of elevated pCO 2 and nutrient enrichment on the growth, photosynthesis, and biochemical compositions of the brown alga Saccharina japonica (Laminariaceae, Phaeophyta). PeerJ 2019; 7:e8040. [PMID: 31799072 PMCID: PMC6884996 DOI: 10.7717/peerj.8040] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Accepted: 10/15/2019] [Indexed: 01/03/2023] Open
Abstract
Ocean acidification and eutrophication are two major environmental issues affecting kelp mariculture. In this study, the growth, photosynthesis, and biochemical compositions of adult sporophytes of Saccharina japonica were evaluated at different levels of pCO2 (400 and 800 µatm) and nutrients (nutrient-enriched and non-enriched seawater). The relative growth rate (RGR), net photosynthetic rate, and all tested biochemical contents (including chlorophyll (Chl) a, Chl c, soluble carbohydrates, and soluble proteins) were significantly lower at 800 µatm than at 400 µatm pCO2. The RGR and the contents of Chl a and soluble proteins were significantly higher under nutrient-enriched conditions than under non-enriched conditions. Moreover, the negative effects of the elevated pCO2 level on the RGR, net photosynthetic rate, Chl c and the soluble carbohydrates and proteins contents were synergized by the elevated nutrient availability. These results implied that increased pCO2could suppress the growth and biochemical composition of adult sporophytes of S. japonica. The interactive effects of ocean acidification and eutrophication constitute a great threat to the cultivation of S. japonica due to growth inhibition and a reduction in quality.
Collapse
Affiliation(s)
- Yaoyao Chu
- College of Fisheries, Ocean University of China, Qingdao, Shandong, China
| | - Yan Liu
- College of Fisheries, Ocean University of China, Qingdao, Shandong, China.,The Key Laboroatory of Mariculture (Ocean University of China), Ministry of Education, Qingdao, Shandong, China
| | - Jingyu Li
- College of Fisheries, Ocean University of China, Qingdao, Shandong, China.,The Key Laboroatory of Mariculture (Ocean University of China), Ministry of Education, Qingdao, Shandong, China
| | - Qingli Gong
- College of Fisheries, Ocean University of China, Qingdao, Shandong, China.,The Key Laboroatory of Mariculture (Ocean University of China), Ministry of Education, Qingdao, Shandong, China
| |
Collapse
|
13
|
Wu H, Feng J, Li X, Zhao C, Liu Y, Yu J, Xu J. Effects of increased CO 2 and temperature on the physiological characteristics of the golden tide blooming macroalgae Sargassum horneri in the Yellow Sea, China. MARINE POLLUTION BULLETIN 2019; 146:639-644. [PMID: 31426203 DOI: 10.1016/j.marpolbul.2019.07.025] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2019] [Revised: 07/11/2019] [Accepted: 07/11/2019] [Indexed: 06/10/2023]
Abstract
The golden tide, caused by the brown algae Sargassum horneri, exerts severe influences on the Pyropia aquaculture of Jiangsu coast, China. To study the outbreak of the golden tide in response to increasing greenhouse gas emissions, S. horneri was cultured under four conditions: ambient condition (10 °C, 400 μatm), elevated temperature condition (14 °C, 400 μatm), elevated CO2 level (10 °C, 1000 μatm), and potential greenhouse condition (14 °C, 1000 μatm). The growth, photosynthetic performances, and inorganic carbon affinity of S. horneri were studied. The results showed that elevated temperature exerted a more pronounced positive influence on S. horneri growth, photosynthesis, and carbon assimilation than CO2 enrichment. The growth of S. horneri was significantly improved by moderately elevated temperatures, especially under concurrently elevated CO2 levels. This suggests that the greenhouse effect will benefit growth and carbon sequestration of S. horneri, which may enhance the frequency and scale of golden tides.
Collapse
Affiliation(s)
- Hailong Wu
- Jiangsu Key Laboratory of Marine Bioresources and Environment, Jiangsu Ocean University, Lianyungang 222005, China; Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Jiangsu Ocean University, Lianyungang 222005, China
| | - Jingchi Feng
- Jiangsu Key Laboratory of Marine Bioresources and Environment, Jiangsu Ocean University, Lianyungang 222005, China; Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Jiangsu Ocean University, Lianyungang 222005, China
| | - Xinshu Li
- Jiangsu Key Laboratory of Marine Bioresources and Environment, Jiangsu Ocean University, Lianyungang 222005, China; Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Jiangsu Ocean University, Lianyungang 222005, China
| | - Chunyan Zhao
- Jiangsu Key Laboratory of Marine Bioresources and Environment, Jiangsu Ocean University, Lianyungang 222005, China; Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Jiangsu Ocean University, Lianyungang 222005, China
| | - Yanhong Liu
- Jiangsu Key Laboratory of Marine Bioresources and Environment, Jiangsu Ocean University, Lianyungang 222005, China; Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Jiangsu Ocean University, Lianyungang 222005, China
| | - Jintao Yu
- Jiangsu Key Laboratory of Marine Bioresources and Environment, Jiangsu Ocean University, Lianyungang 222005, China; Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Jiangsu Ocean University, Lianyungang 222005, China
| | - Juntian Xu
- Jiangsu Key Laboratory of Marine Bioresources and Environment, Jiangsu Ocean University, Lianyungang 222005, China; Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Jiangsu Ocean University, Lianyungang 222005, China.
| |
Collapse
|
14
|
Bao M, Hu L, Fu Q, Gao G, Li X, Xu J. Different Photosynthetic Responses of Pyropia yezoensis to Ultraviolet Radiation Under Changing Temperature and Photosynthetic Active Radiation Regimes. Photochem Photobiol 2019; 95:1213-1218. [PMID: 30968421 DOI: 10.1111/php.13108] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Accepted: 04/02/2019] [Indexed: 11/27/2022]
Abstract
Macroalgae play a crucial role in coastal marine ecosystems, but they are also subject to multiple challenges due to tidal and seasonal alterations. In this work, we investigated the photosynthetic response of Pyropia yezoensis to ultraviolet radiation (PAR: 400-700 nm; PAB: 280-700 nm) under changing temperatures (5, 10 and 15°C) and light intensities (200, 500 and 800 μmol photons m-2 s-1 ). Under low light intensity (200 μmol photons m-2 s-1 ), P. yezoensis showed the lowest sensitivity to ultraviolet radiation, regardless of temperature. However, higher temperatures inhibited the repair rates (r) and damage rates (k) of photosystem II (PSII) in P. yezoensis. However, under higher light intensities (500 and 800 μmol photons m-2 s-1 ), P. yezoensis showed higher sensitivity to UV radiation. Both r and the ratio of repair rate to damage rate (r:k) were significantly inhibited in P. yezoensis by PAB, regardless of temperature. In addition, higher temperatures significantly decreased the relative UV-inhibition rates, while an increased carbon fixation rate was found. Our study suggested that higher light intensities enhanced the sensitivity to UV radiation, while higher temperatures could relieve the stress caused by high light intensity and UV radiation.
Collapse
Affiliation(s)
- Menglin Bao
- Jiangsu Key Laboratory of Marine Bioresources and Environment, Huaihai Institute of Technology, Lianyungang, China
| | - Lili Hu
- Jiangsu Key Laboratory of Marine Bioresources and Environment, Huaihai Institute of Technology, Lianyungang, China
| | - Qianqian Fu
- Jiangsu Key Laboratory of Marine Bioresources and Environment, Huaihai Institute of Technology, Lianyungang, China
| | - Guang Gao
- Jiangsu Key Laboratory of Marine Bioresources and Environment, Huaihai Institute of Technology, Lianyungang, China.,Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Lianyungang, China.,Jiangsu Key Laboratory of Marine Biotechnology, Huaihai Institute of Technology, Lianyungang, China
| | - Xinshu Li
- Jiangsu Key Laboratory of Marine Bioresources and Environment, Huaihai Institute of Technology, Lianyungang, China.,Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Lianyungang, China
| | - Juntian Xu
- Jiangsu Key Laboratory of Marine Bioresources and Environment, Huaihai Institute of Technology, Lianyungang, China.,Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Lianyungang, China.,Jiangsu Key Laboratory of Marine Biotechnology, Huaihai Institute of Technology, Lianyungang, China
| |
Collapse
|
15
|
Quintano E, Celis-Plá PSM, Martínez B, Díez I, Muguerza N, Figueroa FL, Gorostiaga JM. Ecophysiological responses of a threatened red alga to increased irradiance in an in situ transplant experiment. MARINE ENVIRONMENTAL RESEARCH 2019; 144:166-177. [PMID: 30683559 DOI: 10.1016/j.marenvres.2019.01.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Revised: 12/12/2018] [Accepted: 01/14/2019] [Indexed: 06/09/2023]
Abstract
The red alga Gelidium corneum is a dominant foundation species in the south-eastern Bay of Biscay, where a decline in its populations has been documented in the few last decades. We investigated the ecophysiological responses of G. corneum to different light conditions by means of an in situ transplant experiment. We found that the stress response measured by physiological and biochemical approaches was higher in G. corneum at higher irradiance levels, for both transplanted and control specimens, than under lower light intensities. In the former case the specimens showed a decrease in maximum quantum yield (Fv/Fm), maximum electron transport rate (ETRmax), photosynthetic efficiency (αETR), photosynthetic pigment contents, nitrogen content and thallus length, whereas the C:N ratio, MAAs and bleaching cover increased. In general terms, these responses were more evident in the apical parts of the thallus than in middle ones. Our results suggest that high light stress at depths of 3 m triggered photobiological changes in G. corneum, involving ineffective photoprotection and the occurrence of chronic photoinhibition. Therefore, considering the upward trend in summer mean surface solar radiation in the study area since the 80s, high light conditions may have played a role in the declines observed in G. corneum beds from the south-eastern Bay of Biscay.
Collapse
Affiliation(s)
- Endika Quintano
- Department of Plant Biology and Ecology, University of the Basque Country (UPV/EHU), PO Box 644, 48080, Bilbao, Spain.
| | - Paula S M Celis-Plá
- Laboratory of Coastal Environmental Research, Centre of Advanced Studies, University of Playa Ancha, Calle Traslaviña 450, 2581782, Viña del Mar, Chile
| | - Brezo Martínez
- Department of Ecology, Faculty of Sciences, University of Málaga, 29071, Málaga, Spain
| | - Isabel Díez
- Department of Plant Biology and Ecology, University of the Basque Country (UPV/EHU), PO Box 644, 48080, Bilbao, Spain
| | - Nahiara Muguerza
- Department of Plant Biology and Ecology, University of the Basque Country (UPV/EHU), PO Box 644, 48080, Bilbao, Spain
| | - Félix L Figueroa
- Biodiversity and Conservation Unit, Rey Juan Carlos University, 28933, Móstoles, Spain
| | - José M Gorostiaga
- Department of Plant Biology and Ecology, University of the Basque Country (UPV/EHU), PO Box 644, 48080, Bilbao, Spain
| |
Collapse
|