Pedro de Souza Pereira

Coastal Erosion at Maria Farinha Beach, Pernambuco, Brazil: Possible Causes and Alternatives for Shoreline Protection

ABSTRACT Mallmann, D.L.B. and Pereira, P.S., 2014. Coastal erosion at Maria Farinha Beach, Pernambuco, Brazil: Possible causes and alternatives for shoreline protection. The aim of this study is to understand the main processes that are involved in the erosion of Maria Farinha Beach, in Recife, Brazil, a beach of great ecological and socioeconomic importance. Currently, the southern part of the beach is exposed to more frequent periods of erosion, especially during spring tides, while in the northern part accretion can be observed. The possible causes of erosion can be related to: (i) changes in longshore drift rates, resulting in a negative sediment budget; (ii) the impact of the incoming waves, that concentrate energy in a small sector, and/or (iii) urban development on top of the beach system. In order to minimize erosion problems, the following alternatives are suggested: (i) the construction of a submerged breakwater; (ii) the use of a sand bypassing system and (iii) the relocation of existing buildings. It is concluded that the erosion problem at Maria Farinha is complex and difficult to solve, since it has multiple causes.

MODELAGEM FUZZY APLICADA NA DETECÇÃO DA VULNERABILDADE À EROSÃO COSTEIRA

O crescimento da urbanizacao vem provocando grandes transformacoes nas relacoes sociais e morfologica das areas costeiras. O presente trabalho tem como objetivo modelar massa de dados de diversas fontes como GNSS (Global Navigation Satellite Systems) e sensoriamento remoto para posteriormente prover a espacializacao da vulnerabilidade costeira a erosao utilizando a logica fuzzy. O metodo aplicado para analise da vulnerabilidade utilizou variaveis linguisticas, particoes fuzzy, intervalos e analises parametricas que caracterizam a modelagem fuzzy. Apos analise, os niveis de vulnerabilidade a erosao costeira ao longo da linha de costa nas cidades do Recife e Jaboatao dos Guararapes no litoral de Pernambuco apresentaram os seguintes resultados: 33,33% da linha de costa possuem vulnerabilidade baixa, 38,15% possui vulnerabilidade moderada, 14,26% vulnerabilidade alta e 14,26% muito alta.

Coastal Erosion at Pau Amarelo Beach, Northeast of Brazil

ABSTRACT Martins, K.A. and Pereira, P.S., 2014. Coastal erosion at Pau Amarelo Beach, northeast of Brazil. This article concerns the erosion at Pau Amarelo Beach in Pernambuco, Brazil. The maintenance of this beach is important for tourists and the community and is significant for the local economy. Pau Amarelo is a highly urbanized area with poor coastal plain. The coast is characterized by the presence of lined reefs running along the shore. In order to understand the causes of the erosion at this site, coastline variation, the displacement of urban areas and wave characteristics were analyzed. It is believed that both the human incursions on the backshore and the intensification of longshore currents in some parts of the coast, caused by wave diffraction at the reefs, contribute to the beach erosion. The breakwaters built south of Pau Amarelo are also believed to decrease sediment transport by blocking the drift current. Beach nourishment is suggested as the most suitable solution to the erosion at Pau Amarelo.

The Influence of Climate Change on Coastal Erosion Vulnerability in Northeast Brazil

In this paper, an adapted methodology to evaluate coastal erosion vulnerability, which provides a basis for decision-making concerning risk management strategies, is described. The vulnerability evaluation was based on weighted indicators and assessed the vulnerability under different climate change scenarios. To generate the vulnerability index, dynamic processes, geo-indicators, and social and morphological parameters associated with modeled scenarios of sea level rise and predicted wave height changes were integrated. The study area included the sandy beaches in Pernambuco, NE Brazil, and was used to describe the practical application of this approach. Because the occupation of large sectors of the coastline was low, the vulnerability was concentrated in urbanized areas. The high-vulnerability sections of the coast were those with high population densities, high-rise buildings, induced coastal squeeze and hard engineering structures. The low-vulnerability beaches generally had low urbanization rates and well-conserved, resilient coastlines. Under future scenarios, the vulnerability of this coastal region will increase with sea level rise and wave height changes.

Tannic acid affects the phenotype of Staphylococcus aureus resistant to tetracycline and erythromycin by inhibition of efflux pumps

The widespread use of antibiotics created selective pressure for the emergence of strains that would persist despite antibiotic toxicity. The bacterial resistance mechanisms are several, with efflux pumps being one of the main ones. These pumps are membrane proteins with the function of removing antibiotics from the cell cytoplasm. Due to this importance, the aim of this work was to evaluate the inhibitory effect of tannic acid against efflux pumps expressed by the Staphylococcus aureus RN4220 and IS-58 strains. The efflux pump inhibition was assayed using a sub-inhibitory concentration of efflux pump standard inhibitors and tannic acid (MIC/8), observing their capacity to decrease the MIC of Ethidium bromide (EtBr) and antibiotics due the possible inhibitory effect of these substances. The MICs of EtBr and antibiotics were significantly different in the presence of tannic acid, indicating the inhibitory effect of this product against efflux pumps of both strains. These results indicate the possible usage of tannic acid asan inhibitor and an adjuvant in the antibiotic therapy against multidrug resistant bacteria (MDR).

Tropical Sandy Beaches of Pernambuco State

Pernambuco state is located in the Northeast region of Brazil and has a 187 km long coastline containing a range of coastal environments including beaches, estuaries, reefs and headlands all with varying degrees of preservation and occupation. The coast of which 156 km (83 %), is sandy beaches, can be divided into three physiographic sectors. Sand deposits are limited to a narrow strip of the Holocene beach area, deposited between the low-water line and the Holocene terraces. They are predominately quartz, with some beaches containing heavy minerals. The shoreface and the inner shelf has a highly complex underwater topography owing to the presence of beachrock, coral and algae reefs structures at several different depths, as well as paleochannels and other features. The coast has three well defined zonation in terms of wave energy: (1) Goiana to Paulista city, has a high wave convergence zone offshore with a high dissipation/diffraction rates across the inner shelf due to its wide reefs and shallow shelf resulting in low waves at the shore; (2) Paulista to Cabo city, an intermediate wave convergence zone marked by few divergence zones at low tide; (3) Ipojuca to Sao Jose da Coroa Grande city there are fewer convergence zones but the inner shelf has numerous discontinuous reefs inducing refraction and diffraction patterns. This pattern is controls the shoreline morphology and beach morphodynamic behavior. Based on this the beaches can be divided into three sectors: with the reef protected northern beaches are tide-modified; the exposed southern beaches are wave-dominated; and the middle sector beaches where the beachrock reefs controls the relation between wave and tide are geomorphologically controlled.

Sandy Beaches of Brazilian Oceanic Islands

Brazil has four oceanic islands, three of which are discussed in this chapter: Rocas atoll, Fernando de Noronha and Trindade. Each of these islands is located on seafloor fracture zones extending east of the coast. Rocas and Fernando de Noronha lie 260 and 360 km respectively east of Natal. Rocas consists of a coral atoll, containing in its lagoon three sandy cays with dynamic beaches. The atoll is uninhabited and only visited by scientists. The Fernando de Noronha archipelago contains 21 islands the largest of which is inhabited and contains 15 sandy beaches, some considered the most beautiful in Brazil. It is a popular tourist and surfing destination. Trindade lies 1140 km east of Vitoria and is a bare volcanic peak manned by a Naval base with a oceanographic research station and containing 12 sandy and cobble beaches, including the deadly “camel wave”. The islands and their variety of beaches are presented in this chapter.

Behavior and identification of ephemeral sand dunes at the backshore zone using video images

The backshore zone is transitional environment strongly affected by ocean, air and sand movements. On dissipative beaches, the formation of ephemeral dunes over the backshore zone plays significant contribution in the beach morphodynamics and sediment budget. The aim of this work is to describe a novel method to identify ephemeral dunes in the backshore region and to discuss their morphodynamic behavior. The beach morphology is identified using Argus video imagery, which reveals the behavior of morphologies at Cassino Beach, Rio Grande do Sul, Brasil. Daily images from 2005 to 2007, topographic profiles, meteorological data, and sedimentological parameters were used to determine the frequency and pervasiveness of these features on the backshore. Results indicated that coastline orientation relative to the dominant NE and E winds and the dissipative morphological beach state favored aeolian sand transport towards the backshore. Prevailing NE winds increase sand transportation to the backshore, resulting in the formation of barchans, transverse, and barchanoid-linguiod dunes. Precipitation inhibits aeolian transport and ephemeral dune formation and maintains the existing morphologies during strong SE and SW winds, provided the storm surge is not too high.

Vitamin K enhances the effect of antibiotics inhibiting the efflux pumps of Staphylococcus aureus strains

The strain Staphylococcus aureus is commonly cited as being a major hospital-acquired pathogen. The emergence of S. aureus strains resistant to a wide distribution of antibiotics. The various antibiotic resistance mechanisms include efflux pumps, are ubiquitous proteins localized in the cytoplasmic membrane of all kind of cells. During the last two decades, numerous structurally diverse compounds have been studied and shown to have efflux-inhibitory activity. These include currently available drugs employed for other indications, as well as natural and synthetic molecules. Menadione (vitamin K3), is a fat-soluble vitamin that has long been recognized for its essential role in coagulation and, more recently, has been proposed as a key nutrient in the regulation of soft tissue calcification. Therefore, the aim of this study is to evaluate the effect of menadione efflux pumps in multidrug resistant strains of S.aureus. Were used RN4220 harboring plasmid pUL5054, which carries the gene encoding the MsrA macrolide efflux protein; and IS-58, which possesses the TetK tetracycline efflux protein; 1199B resists hydrophilic fluoroquinolones via a NorA-mediated mechanism and wild strain 1199B. Antibacterial activity test by minimal inhibitory concentration (MIC). Evaluation of possible inhibition of efflux pumps by reduction of MIC of ethidium bromide (EtBr) and antibiotics due the possible inhibitory effect of these substances. Efforts have been directed at identification of EPIs from natural sources. Some of the detrimental effects on bacterial cells can be attributed to the detergent properties of menadione on account of their amphipathic structure. Was observed what in strain 4220 and IS58 it occurred reduction the MIC, indicating possible effect on efflux pump.

Cytotoxic and anti-kinetoplastid potential of the essential oil of Alpinia speciosa K. Schum

Alpinia speciosa K. Schum, known as colônia (colony), is native to tropical Asia and found in parts of tropical America. Its leaves are used to wrap food, rhizomes for food preparation and seeds for health maintenance, and have been widely used by the population as a diuretic, antihypertensive, antiulcerogenic and sedative. The present study aimed to verify the leishmanicidal and trypanocidal potential, as well as the cytotoxicity, of the A. speciosa essential oil, in vitro. A. speciosa presented 1,8-cineole (28.46%), camphor (17.10%) and sabinene (9.95%) as major constituents. The cytotoxic activity of the essential oil presented a low value, while the antipromastigote and antiepimastigote activity presented values considered clinically relevant, since it had an action below 500 μg/mL. In relation to this study, it can be concluded that this is a pioneer in the potential of the A. speciosa essential oil and in the use against the parasites Trypanosoma cruzi Chagas and Leishmania brasiliensis Vianna, having its importance also rooted in this fact. Still in accordance with the results, A. speciosa was effective because it presented values of clinical relevance and low toxicity. It was also observed that the chemical constitution of the above identified compounds with remarkable antiparasitic activities.