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This study is a paleoenvironmental and paleoclimatic analysis of beachrocks through oxygen and carbon isotopes on its cement. The beachrocks have from 60% to 85% of its basis formed by detrital grains of quartz and its carbonate cement is composed by Magnesium-rich calcite. Isotopic values from -1.1‰ to 3.5‰ were obtained for δ 13 C and from -0.9‰ to 0.5‰ for δ 18 O VPDB. Those values are typical of those from sea carbonate cement deposited on shallow marine environment and under the influence of fresh water (meteoric vadose environment), which causes cementation on the foreshore zone. Paleotemperature of the beachrock cement ranged from 22.9ºC to 28.2ºC. This variation is due to the rise of the precipitation depth of the cement and indicates that the water temperature was fairly constant during the process of deposition of the carbonate cement.

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This work aims to understand beachrock formation during Holocene through petrology, geochemistry and dating of a core located 5,43m deep in relation to present-day sea-level in the Piedade Beach in Jaboatao dos Guararapes-PE. The core is located 143 meters distant from the coast line towards mainland. Four lithofacies have been identified, taking into account differences in texture and sedimentary structures. The framework grain size ranges from medium to very coarse sand, indicating variations in depositional energy. Petrographic data indicate that the beachrocks have values of 64.23% to 70.69% of framework composed of quartz grains. Carbonate cement (represents 13.5%) consisting of high magnesium calcite surrounding grains as isopachous fringe (4.15% to 11.95%), micritic cement (0.60% to 6.42%) and equant cement (0.26% to 7.01%), indicates marine environment precipitation. The results of the isotopic composition of carbon and oxygen present valuesof 3.09‰ to 3.89‰, with an average of 3.63‰ to δ 13 C PDB and of-0.91‰ to 0.96‰, with an average of 0.54‰ to δ 18 O PDB, suggesting that the cement is formed in a shallow marine environment with freshwater influence. The values obtained in paleotemperature vary from 21ºC to 30ºC, with an average of 23ºC, with little variation indicating precipitation in a shallow water environment. In the study area, the beachrocks are indicators of sea level and the results suggest that between 7.509 years B.P. and 5982 years B.P. there was a marine transgression process, with sea level 9.18 m lower than the current sea level.

Este trabalho se pauta pela crescente urbanização na região costeira da cidade do Recife e como isso afeta a oferta dos serviços ecossistêmicos ao decorrer do litoral recifense. Buscou-se, também, as especificações das diferenças sobre percepção ambiental nas praias do Pina e Boa Viagem, localizadas na cidade de Recife, Pernambuco.  Para a caracterização das diferentes percepções que os frequentadores possuem acerca da praia e dos arenitos e para inventariar os serviços ecossistêmicos, foram feitas aplicações de questionários e o preenchimento de ficha de campo. Os entrevistados possuem percepções diferentes acerca de aspectos negativos, variando de acordo com a praia frequentada, com a praia do Pina possuindo menos atrativos negativos do que a praia de Boa Viagem. Em relação à presença dos arenitos de praia na orla, houve uníssono positivo para a importância das formações areníticas na proteção tanto da costa, quanto de quem frequenta ambas as praias. Em relação aos serviços ecossistêmicos, a praia se mostrou com nuances heterogêneas e diferenciações características entre si, com setores apresentando maiores índices de um determinado tipo de serviço do que outros, com destaque para o Parque Dona Lindu, no segundo setor e massiva presença de vegetação na zona antepraia no quarto setor. Houve a constatação de que os setores com maior aporte de serviços de regulação e suporte possuíam mais atrativos físicos e sociais para os usuários.   A B S T R A C TThis research sought the specifications of the differences on environmental perception and ecosystem services applied on the beaches of Pina and Boa Viagem, located in the city of Recife, Pernambuco. In order to obtain the characterization of different perceptions that the visitors have about the beach, the beachrocks and to inventory the ecosystem services. Two methodological tools were used, they are: questionnaire applications and field file completion, respectively. The interviewees have different perceptions about negative aspects, varying according to the beach frequented, with Pina beach having less negative attractions than Boa Viagem beach. In relation to the presence of beachrocks on the shore, there was a positive unison for the importance of beachrock formations in protection of both the coast and those who frequent both beaches. In relation to ecosystem services, the beach was shown with heterogeneous nuances and differentiations characteristic of each other, with sectors presenting higher rates of a certain type of service than others, especially the Dona Lindu Park, in the second sector and massive presence of vegetation in the shoreface zone in fourth sector. It was obsereved that sectors with the greatest contribution of regulation and support services had more physical and social attractiveness for the users.Keywords: environmental perception; ecosystem services; beach.