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Lane-Medeiros L, Puppin-Gonçalves CT, Angelini R, Lira AS, Lucena-Frédou F, Freire FAM. Macroalgal blooms affect the food web of tropical coastal ecosystems impacted by fisheries. MARINE ENVIRONMENTAL RESEARCH 2023; 184:105858. [PMID: 36630747 DOI: 10.1016/j.marenvres.2022.105858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Revised: 12/21/2022] [Accepted: 12/21/2022] [Indexed: 06/17/2023]
Abstract
Macroalgal bloom events have been frequent in recent years. Eutrophication and overexploitation fishing may favor blooms through nutrient availability and capturing top predators. We aim to investigate the drivers of the macroalgae blooms and their consequences on the food web of the two tropical coastal ecosystems: Porto do Mangue (with high macroalgae production) and Baía Formosa (control environment, without macroalgae), both exploited by artisanal fisheries in northeastern Brazil. The food webs are modeled using the Ecopath with Ecosim (EwE) approach. Our results suggest that fishing did not favor macroalgae blooms but rather the high concentration of nutrients added to the semi-arid conditions. Furthermore, the macroalgae bloom showed low trophic impact, so much of their biomass is transferred into detritus. However, when it decomposes, this accumulation of matter alters the structure and functioning of the ecosystem, affecting its main fish resources: shrimp and piscivorous fish. Investigating blooms is key to management.
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Affiliation(s)
- L Lane-Medeiros
- Laboratório de Ecologia e Evolução de Crustáceos, Universidade Federal do Rio Grande do Norte (UFRN), DBZ, Campus Universitário s/n, Natal, RN, 59098-970, Brazil; Programa de Pós-graduação em Ecologia, Universidade Federal do Rio Grande do Norte (UFRN), DECOL, Campus Universitário s/n, Natal, RN, 59098-970, Brazil.
| | - C T Puppin-Gonçalves
- Laboratório de Ecologia e Evolução de Crustáceos, Universidade Federal do Rio Grande do Norte (UFRN), DBZ, Campus Universitário s/n, Natal, RN, 59098-970, Brazil
| | - R Angelini
- Programa de Pós-graduação em Ecologia, Universidade Federal do Rio Grande do Norte (UFRN), DECOL, Campus Universitário s/n, Natal, RN, 59098-970, Brazil; Departamento de Engenharia Civil e Ambiental, Universidade Federal do Rio Grande do Norte (UFRN), CTec, Campus Universitário s/n, Natal, RN, 59098-970, Brazil
| | - A S Lira
- Universidade Federal de Sergipe, Departamento de Pesca e Aquicultura, Av. Marechal Rondon Jardim s/n - Rosa Elze, São Cristóvão - Sergipe, 49100-000, Brazil
| | - F Lucena-Frédou
- Laboratório de Estudos de Impactos Antrópicos na Biodiversidade Marinha e Estuarina, Universidade Federal Rural de Pernambuco (UFRPE), DEPAq, Av. Dom Manuel s/n, Recife, PE, 52171-900, Brazil
| | - F A M Freire
- Laboratório de Ecologia e Evolução de Crustáceos, Universidade Federal do Rio Grande do Norte (UFRN), DBZ, Campus Universitário s/n, Natal, RN, 59098-970, Brazil; Programa de Pós-graduação em Ecologia, Universidade Federal do Rio Grande do Norte (UFRN), DECOL, Campus Universitário s/n, Natal, RN, 59098-970, Brazil
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Umanzor S, Ramírez-García MM, Sandoval-Gil JM, Zertuche-González JA, Yarish C. Photoacclimation and Photoprotection of Juvenile Sporophytes of Macrocystis pyrifera (Laminariales, Phaeophyceae) Under High-light Conditions During Short-term Shallow-water Cultivation 1. JOURNAL OF PHYCOLOGY 2020; 56:380-392. [PMID: 31804706 DOI: 10.1111/jpy.12951] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2019] [Accepted: 11/07/2019] [Indexed: 05/16/2023]
Abstract
This study was designed to understand better if and how juvenile sporophytes of Macrocystis pyrifera can photoacclimate to high-light conditions when transplanted from 10 to 3 meters over 7 d. Acclimation of adult sporophytes to light regimes in the bathymetric gradient has been extensively documented. It primarily depends on photoacclimation and translocation of resources among blades. Among other physiological differences, juvenile sporophytes of M. pyrifera lack the structural complexity shown by adults. As such, juveniles may primarily depend on their photoacclimation capacities to maintain productivity and even avoid mortality under changing light regimes. However, little is known about how these mechanisms operate in young individuals. The capacity of sporophytes to photoacclimate was assessed by examining changes in their photosynthetic performance, pigment content, and bio-optical properties of the blade. Sporophytes nutritional status and oxidative damage were also determined. Results showed that juvenile sporophytes transplanted to shallow water were able to regulate light harvesting by reducing pigment concentration, and thus, absorptance and photosynthetic efficiency. Also, shallow-water sporophytes notably enhanced the dissipation of light energy as heat (NPQ) as a photoprotective mechanism. Generally, these adjustments allowed sporophytes to manage the absorption and utilization of light energy, hence reducing the potential for photo-oxidative damage. Furthermore, no substantial changes were found in the internal reserves (i.e., soluble carbohydrates and nitrogen) of these sporophytes. To our knowledge, these results are the first to provide robust evidence of photoprotective and photoacclimation strategies in juveniles of M. pyrifera, allowing them to restrict or avoid photodamage during shallow-water cultivation.
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Affiliation(s)
- Schery Umanzor
- Department of Ecology and Evolutionary Biology, University of Connecticut, Stamford, Connecticut, 06901, USA
| | - Mary Mar Ramírez-García
- Instituto de Investigaciones Oceanológicas, Universidad Autónoma de Baja California, Km 106 Carretera Tijuana-Ensenada, Ensenada, Baja California 22860, México
| | - Jose Miguel Sandoval-Gil
- Instituto de Investigaciones Oceanológicas, Universidad Autónoma de Baja California, Km 106 Carretera Tijuana-Ensenada, Ensenada, Baja California 22860, México
| | - José Antonio Zertuche-González
- Instituto de Investigaciones Oceanológicas, Universidad Autónoma de Baja California, Km 106 Carretera Tijuana-Ensenada, Ensenada, Baja California 22860, México
| | - Charles Yarish
- Department of Ecology and Evolutionary Biology, University of Connecticut, Stamford, Connecticut, 06901, USA
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