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Frederico Brandini 《Regional Environmental Change》2014,14(6):2127-2137
The subtropical coastal zone of Paraná state in southern Brazil is only 80 km long yet environmentally diverse, with relatively pristine coastal landscapes and high marine and coastal biodiversity supporting important artisanal fishing grounds. However, this region began to change in the early 1970s. The development of industrial harbors, as well as unregulated tourism and urban settlement and pollution caused the loss of natural habitats. In addition, commercial shrimp trawlers began to operate in the adjacent shallow shelf areas. Biodiversity was seriously affected, and local fish stocks have decreased drastically in the last four decades. This article describes a long-term program to protect coastal habitats, recover marine biodiversity and diversify the economic base of fishing communities in order to guarantee fish stocks for future generations, hence preserving the social and cultural identities of these communities. Although it is difficult to change traditional fishing practices, fishing communities may exploit alternate components of the marine biological resources in order to achieve environmental, social and cultural sustainability in the long term. 相似文献
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Luiz Carlos Cotovicz Junior Nilva Brandini Bastiaan Adriaan Knoppers Byanka Damian Mizerkowski José Mauro Sterza Alvaro Ramon Coelho Ovalle Paulo Ricardo Petter Medeiros 《Environmental monitoring and assessment》2013,185(4):3297-3311
Anthropogenic eutrophication of aquatic ecosystems continues to be one of the major environmental issues worldwide and also of Brazil. Over the last five decades, several approaches have been proposed to discern the trophic state and the natural and cultural processes involved in eutrophication, including the multi-parameter Assessment of Estuarine Trophic Status (ASSETS) index model. This study applies ASSETS to four Brazilian lagoons (Mundaú, Manguaba, Guarapina, and Piratininga) and one estuarine delta (Paraíba do Sul River), set along the eastern Brazilian coast. The model combines three indices based on the pressure–state–response (PSR) approach to rank the trophic status and forecast the potential eutrophication of a system, to which a final ASSETS grade is established. The lagoons were classified as being eutrophic and highly susceptible to eutrophication, due primarily to their longer residence times but also their high nutrient input index. ASSETS classified the estuary of the Paraíba do Sul river with a low to moderate trophic state (e.g., largely mesotrophic) and low susceptibility to eutrophication. Its nutrient input index was high, but the natural high dilution and flushing potential driven by river flow mitigated the susceptibility to eutrophication. Eutrophication forecasting provided more favorable trends for the Mundaú and Manguaba lagoons and the Paraíba do Sul estuary, in view of the larger investments in wastewater treatment and remediation plans. The final ASSETS ranking system established the lagoons of Mundaú as “moderate,” Manguaba as “bad,” Guarapina as “poor,” and Piratininga as “bad,” whereas the Paraíba do Sul River Estuary was “good.” 相似文献
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Frederico P. Brandini Eduardo T. da Silva Franciane M. Pellizzari Alessandra L. O. Fonseca Luciano F. Fernandes 《Marine Biology》2001,138(1):163-171
Production rates, chlorophyll concentrations and general composition of periphytic diatom communities growing on glass slides
were studied in relation to environmental parameters during one seasonal cycle in the Bay of Paranaguá, southern Brazil. Slides
were routinely submersed at 1, 2 and 3 m depth and recovered weekly for microscopic examinations, analyses of chlorophyll,
cell counts and in situ photosynthetic incubations using the Winkler titration method. Water samples were also collected at
surface and bottom layers for determinations of temperature, salinity, nutrients and chlorophyll in the water. The periphytic
community was mainly formed by epipelic and epipsammic species, dominated by Navicula phyllepta, Cylindrotheca closterium, Navicula spp. and Amphora sp. Weekly chlorophyll a and cell accumulations on slides varied from <1–32 mg m−2 and up to 31 × 108 cells m−2, respectively. Photosynthetic rates varied from <1 to 35 mg oxygen mg chlorophyll a
−1 h−1, with higher values in summer. Daily production varied from 5 to 3,600 mg oxygen m−2 day−1 (<0.01–1.4 g carbon m−2 day−1). Multiple regression analysis revealed that vertical differences in light conditions and grazing pressure jointly affected
the influence of temperature on the seasonal patterns of cell densities and chlorophyll concentrations according to depth.
Received: 27 April 2000 / Accepted: 16 August 2000 相似文献
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