Descripción del gran ecosistema marino del noreste de Brasil usando un modelo trófico

Freire, Katia Felizola; Christensen, Villy; Pauly, Daniel

doi:10.3989/scimar.2008.72n3477

Cited by 11 publications

(5 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This subprovince extends from eastern tip of the mouth of the southern channel of the Amazon estuary to Parnaíba coast (Delta do Parnaíba; 2 • 43 S), state of Piauí. (iii) The Northeastern semiarid (NS) subprovince (2-5 • S) comprises a coastline of 720 km dominated by mobile dune fields propelled by south-easterly and easterly trade winds, which reach speeds of over 15 m/s (Freire et al, 2008). Low riverine input and clear and salty waters (annual salinity range 32-42) are characteristics of this region, in addition to relatively reduced mangrove forest cover along the coastline in comparison with the AE and NM subprovinces.…”

Section: Study Areamentioning

confidence: 99%

Intertidal Biogeographic Subprovinces: Local and Regional Factors Shaping Fish Assemblages

et al. 2018

View full text Add to dashboard Cite

Intertidal zones shelter a wealth of species and natural resources, provide important ecological services, and sustain several economic activities in coastal communities. However, the tidepool fish species that inhabit the intertidal zone are subject to a wide array of impacts due to the human presence and their accessibility, creating a challenge for the mitigation of habitat loss, in particular in tropical regions where the ecology and distribution of species are poorly known. In this study, we investigated tidepool fish species distribution patterns systematically across ca. 4,900 km of tropical Brazilian coastline (00-21 • latitude) in order to verify the latitudinal trends and environmental variables influencing tidepool communities. A total of 5,113 fish specimens belonging to 67 taxa were collected at the 19 sites, revealing four distinct biogeographic subprovinces: Amazon Estuary (AE), Northern Mangrove (NM), Northeastern Semiarid (NS), and Tropical Warm (TW). Distance-based linear modeling evidenced in sequence water salinity, tidal range, shape of rocky shore formation, algae cover, distance to subtidal zone, latitude and rainfall as the most important environmental variables to shape biogeographic subprovinces. Fish species such as Bathygobius soporator, Bathygobius geminatus, Labrisomus nuchipinnis, and Scartella cristata presented wide distribution, occupying more than one subprovince. The trophic structure of the tidepool fishes also varied among subprovinces, with carnivores being associated with the AE subprovince, omnivores with the NM, and herbivores dominating the NS and TW. These findings reinforce the determining role of local and regional factors in the geographic distribution of fish and, in particular, highlight a new arrangement for the intertidal subprovinces of the tropical Brazilian shoreline, which may provide a valuable tool for the more effective management and conservation of this vulnerable ecosystem at the land-ocean interface.

show abstract

Section: Study Areamentioning

confidence: 99%

Intertidal Biogeographic Subprovinces: Local and Regional Factors Shaping Fish Assemblages

et al. 2018

View full text Add to dashboard Cite

show abstract

“…Diet compositions in the networks were derived from an isotope study of the region [55,56], and from literature (S3 Table). The fate of biomass not consumed in the systems was assigned to the various [non-living] abiotic groups (S2 Table).…”

Section: Methodsmentioning

confidence: 99%

Stoichiometric multitrophic networks reveal significance of land-sea interaction to ecosystem function in a subtropical nutrient-poor bight, South Africa

Scharler

Ayers

2019

PLoS ONE

View full text Add to dashboard Cite

Nearshore marine ecosystems can benefit from their interaction with adjacent ecosystems, especially if they alleviate nutrient limitations in nutrient poor areas. This was the case in our oligo- to mesotrophic study area, the KwaZulu-Natal Bight on the South African subtropical east coast, which is bordered by the Agulhas current. We built stoichiometric, multitrophic ecosystem networks depicting biomass and material flows of carbon, nitrogen and phosphorus in three subsystems of the bight. The networks were analysed to investigate whether the southern, middle and northern bight function similarly in terms of their productivity, transfer efficiency between trophic levels, material cycling, and nutrient limitations. The middle region of the bight was clearly influenced by nutrient additions from the Thukela River, as it had the highest ecosystem productivity, lower transfer efficiencies and degree of cycling. Most nodes in the networks were limited by phosphorus, followed by nitrogen. The middle region adjacent to the Thukela River showed a lower proportion of P limitation especially in summer. Interestingly, there was a clear distinction in sensitivities to nutrient limitations between lower and higher trophic level organisms. This is a reflection of their discrepant nutrient turnover times that are either higher, or lower, than that of the systems, and which might provide a balance to the system through this antagonistic influence. Furthermore, by tracking the stoichiometry through entire food webs it appeared how important the role of lower trophic level organisms was to regulate stoichiometry to more suitable ratios for higher trophic level requirements. Although we gained good insight into the behaviour of the three subsystems in the KZN Bight and the role of terrestrial influence on their functioning, a merged approach of incorporating data on metabolic constraints derived from experiments could further improve the representativeness of multitrophic stoichiometric ecosystem networks.

show abstract

“…Food-web models suggest that large sharks are among the most strongly interacting species [55], and that their overfishing may have contributed to the degradation of the coral ecosystems in the Caribbean [56]. A 'removal' computer simulation conducted for the reef ecosystem of Floreana Island in the Galápagos Islands found that sharks were at the top of the trophic scale and that their loss caused a four-level trophic cascade [57].…”

Section: The Ecological Consequencesmentioning

confidence: 99%

Shark Fishing vs. Conservation: Analysis and Synthesis

Porcher¹,

Darvell

2022

Sustainability

View full text Add to dashboard Cite

The expanding shark fin market has resulted in intensive global shark fishing and with 90% of teleost fish stocks over-exploited, sharks have become the most lucrative target. As predators, they have high ecological value, are sensitive to fishing pressure, and are in decline, but the secretive nature of the fin trade and difficulties obtaining relevant data, obscure their true status. In consumer countries, shark fin is a luxury item and rich consumers pay high prices with little interest in sustainability or legal trade. Thus, market demand will continue to fuel the shark hunt and those accessible to fishing fleets are increasingly endangered. Current legal protections are not working, as exemplified by the case of the shortfin mako shark, and claims that sharks can be sustainably fished under these circumstances are shown to be misguided. In the interests of averting a catastrophic collapse across the planet’s aquatic ecosystems, sharks and their habitats must be given effective protection. We recommend that all sharks, chimaeras, manta rays, devil rays, and rhino rays be protected from international trade through an immediate CITES Appendix I listing. However, a binding international agreement for the protection of biodiversity in general is what is needed.

show abstract

Descripción del gran ecosistema marino del noreste de Brasil usando un modelo trófico

Cited by 11 publications

References 30 publications

Intertidal Biogeographic Subprovinces: Local and Regional Factors Shaping Fish Assemblages

Intertidal Biogeographic Subprovinces: Local and Regional Factors Shaping Fish Assemblages

Stoichiometric multitrophic networks reveal significance of land-sea interaction to ecosystem function in a subtropical nutrient-poor bight, South Africa

Shark Fishing vs. Conservation: Analysis and Synthesis

Contact Info

Product

Resources

About