Dinâmica costeira entre as praias de Areia Preta e do Forte, Natal/RN

The coastal zone has been studied worldwide with a focus on the coastal erosion. In the present days, much of the world's coastlines are being affected by erosion, which causes great damage to the economy. This work had as study case the beaches of Areia Preta, Artistas, Meio and Forte located in Natal in Rio Grande do Norte. It shows as result the monitoring of the beach strip that makes possible to obtain quantitative and qualitative data, allows the study of the coastal dynamics of the beaches and the Recovery Project of the Areia Preta beach interference on adjacent beaches. This research was guided by the integrated analysis method on the systemic perspective. The pratical procedures adopted were: bibliographic research; fieldwork during eleven months (environmental characterization, collection of hydrodynamic data, topographic leveling, collection of sediments) and; sedimentological analysis of samples collected. By monitoring of the points A, B, C, D and E we were able to find the occurrence of the coastal erosion on their biggest part except by the C and D profiles. It was noted the need for the government to complete the hydraulic fill, as it made only 60% of the landfill planed. It was found that the spikes built on the beach of Areia Preta are preventing the natural transport of sediments that the longshore performs towards South-North. This interference is causing the lack of sediment on the beaches of Forte and Meio and their coastal erosion in consequence

Análise de risco à erosão costeira na região de Tibau do Sul/RN através de mapeamento geoambiental e análise morfodinâmica

The research area is located on the county of Tibau do Sul, in the east coast of Rio Grande do Norte State, about 80km south of the capital Natal. The tourism represents the main income activity and Pipa beach is the most visited beach in the city, annually receives a large influx of domestic and foreign tourists. Some recent studies have reported the occurrence of coastal erosion in this littoral, being the main objective of the research, analyze the existing coastal erosion, through two methodologies, the geoenvironmental mapping and beach morphodynamics. The geoenvironmental mapping was done from oblique aerial photographs and field visits, which sought to carry out first the geomorphological mapping, with the purpose of analyzing features that suggest susceptible areas to erosion, as areas without protection of natural dunes, marine terraces, or sandstones (beach-rocks and ferruginous sandstones), areas with the presence of gullies and stretches where the sea-cliffs were in direct contact with the action of the sea, representing the beginning of the beach profile. In the morphodynamic study sought to carry out the survey of the physical and morphological characteristics, the analysis of sediment grain of the beaches and finally the analysis of the morphodynamic parameters to generate a table of risk to erosion by sector of the beach. The morphodynamic parameters were defined by the methodology proposed by Short (2006), in which considers different patterns of dynamism on beaches with characteristics favorable and unfavorable to erosive profiles. The maps indicated different levels of risk to the segments of the beaches analyzed, suggesting risk to erosion low and low to moderate only in areas north and northwest of the beaches of Madeiro and Curral, and levels of moderate and high risk sectors in the south and southeast of these beaches . The beach of Pipa showed moderate levels of risk and moderate to high at the ends and high risk to erosion in the central portion. The study of the coastal environment, its morphological evolution, and areas with problems of erosion, are of fundamental importance to assist coastal management policies, giving grants for planning activities undertaken in these regions

Monitoramento costeiro das praias de São Bento do Norte e Caiçara do Norte RN: implicações para o pólo petrolífero de Guamaré

This dissertation the results of a research developed in the area of São Bento do Norte and Caiçara do Norte, northern coast of the State of Rio Grande do Norte, during the period of June of 2000 to August of 2001, in the ambit of the projects MAMBMARÉ (CNPq/CTPETRO) and PROBRAL (CAPES/DAAD).The objective principal of this research was the characterization of the sedimentary dynamics of this coast, with base in data of coastal process (winds, currents, waves and tides), with topographical risings (beach profiles and dunes), satellite images and sedimentary analyses. The more specific objectives were accomplished the coastal monitoring of this coast, to verify the maintenance of an erosive tendency or progradacional after the groynes construction for contention of the erosion in the beach of Caiçara do Norte, as well as to verify the influence of the features of bottom of the platform interns adjacent on the pole petroliferous of Guamaré. The executed monitoramento allowed to identify that the movement of the sediments, along the year, in that area, is cyclical, reaching the largest oscillations during the months of winter (deposition) and they will summer (erosion). The sedimentologic studies indicated a general tendency for sands quartzosas, with gravel presence, moderately to good selected, with asymmetry predominantly negative. In agreement with the parameter of Dean (1957), used in the identification of the state morfodinâmico of the beaches, monitored beaches, are basically reflectivas with tendency to middlemen, what frames that space of the coast norteriograndense, as a space strongly vulnerable to erosive processes. The studies developed in the platform, it interns of this area, allowed to visualize for the first time, in large scale, the distribution of the features of the submarine bottom to the batométrico coat of 25 meters. Being pointed out the presence of a high one topographical submerged, with about 5 meters of height, 1 km of width and more than 24 meters of extension, located in the platform it interns in front of São Bento do Norte; coincident with the trend of the system of flaws of Carnaubais. This feature relay an important paper on the control of the sedimentary processes and oceanographic, as well as in the coastal evolution of this area of the RN state, and they affect the area of the pole petroliferous of Guamaré directly. These results contribute to a better knowledge of the processes in the area, and consequently as subsidies implantation of measures of coastal and environmental protection for the cities of São Bento do Norte and Caiçara do Norte, as well as to understand how the geological-sedimentary processes and oceanographic, in this area, are influencing the characteristics geoambientais of the pole petroliferous of Guamaré

Análise da dinâmica deposicional das praias de Cacimbinha e do Madeiro, Tibau do Sul-RN, Brasil

The Cacimbinha and Madeiro beaches are located in the eastern coast of Rio Grande do Norte state, in the municipality of Tibau do Sul. Given the indicative of erosion in the coast of this district and the coastal processes acting on the beaches, the global aim of this project is comprehend the evolution of depositional environment on the Cacimbinha beach, moreover, the project seeks to characterize deposits from the Cacimbinha and Madeiro beaches, according to the geomorphologic compartments identified on these beaches; distinguish the coastal features which possibly interact with the Cacimbinha beach; identify the potential relationship between the sediments from the coastal features and the deposits from Cacimbinha beach; understand which depositional processes that prevail at each facies deposited on the beach; and identify the probable sedimentary environments and its energy of deposition through of the materials recorded on the Cacimbinha beach. This study was based on previous bibliographic and field research, both guided by academic works, laws, concepts and theories concerning the physical geography, geomorphology of the quaternary, sedimentary geology and stratigraphy. Thus, the methodology was divided in three steps: Prefield step: office work was performed; Field step: Sampling of facies of sedimentation; PosField step: analysis and integration of data obtained during the research period. Thus, the results showed deposicional facies with distinguished energy in the relief compartments, beach and terrace. After the sedimentary analysis and its interpretation linked to the architecture of the mounted sections based on drilling, it became possible to trace the evolutionary history of this stretch of beach. Therefore, it can be stated that studies performed on coastal areas are of great importance, as long as, around the world, the most part of urban zones are seated on deposits of quaternary age and, then this work improve the knowledge regarding the sedimentary dynamics of this beach, becoming scientific support for management and planning of this area which focus on, mainly, the foreign tourism

Diagnóstico da possível influência da atividade petrolífera em sedimentos de fundo da Bacia Piranhas-Açu, região Baixo Açu/RN

It is located in an area of increasing oil exploration, the region of the Lower Açu is at the mercy of a possible pollution generated by this economic activity, which includes various chemical substances harmful to health, such as metals. This thesis aims to, diagnose the areas of River Piranhas-Açu, a region of the Lower Açu, which are polluted by traces factors and more. In this study, it was determined the concentration of the chemica elements Al, CD, Cr, Cu, Fe, Mn, Ni, P, Pb, V and Zn, through the technique of ICP-OES analysis and the size of sediments and their contents organic matter. Were mapped by GPS, 12 points from collections. The interpretations of the results, together associating that allowed pollution to a possible contamination by oil activity. The results showed tha some regions have low concentrations of cadmium, lead, copper, manganese and zinc unable to promote damage to human health. However, there are places where the concentrations of certain metals chromium, iron and zinc are moderately polluted compared to the results with the reference values of literature and others that are highly polluted by iron. However, due to a greater number of wells in production in those locations, those higher concentrations, it can be suggested a possible influence of oi production in some areas with concentrations of chromium and lead are higher than the rest of the points of monitoring. Moreover, it is observed that the highest levels of metals found in sediment of finer texture and more organic matter content

Hidrocarbonetos policíclicos aromáticos em sedimentos de fundo do estuário do rio Potengi, região da grande Natal (RN): implicações ambientais

Estuaries are environments prone to the input of chemical pollutants of various kinds and origins, including polycyclic aromatic hydrocarbons (PAHs). Anthropogenic PAHs may have two possible sources: pyrolytic (with four or more aromatic rings and low degree of alkylation) and petrogenic (with two and three aromatic rings and high degree of alkylation). This study aimed to evaluate the levels, distribution and possible sources of polycyclic aromatic hydrocarbons in the estuary of the Potengi river, Natal, Brazil. Samples of bottom sediments were collected in the final 12 km of the estuary until its mouth to the sea, where the urbanization of the Great Natal is more concentrated. Sampling was performed on 12 cross sections, with three stations each, totaling 36 samples, identified as T1 to T36. The non alkylated and alkylated PAHs were analyzed by gas chromatography coupled to mass spectrometry (GC / MS). PAHs were detected in all 36 stations with total concentration on each varying 174-109407 ng g-1. These values are comparable to those of several estuarine regions worldwide with high anthropogenic influence, suggesting the record of diffuse contamination installed in the estuary. PAHs profiles were similar for most stations. In 32 of the 36 stations, low molecular weight PAHs (with 2 and 3 ring: naphthalene, phenanthrene and their alkylated homologues) prevailed, which ranged from 54% to 100% of the total PAH, indicating that leaks, spills and combustion fuels are the dominant source of PAH pollution in the estuary. The level of contamination by PAHs in most stations suggests that there is potential risk of occasional adverse biological effects, but in some stations adverse impacts on the biota may occur frequently. The diagnostic ratios could differentiate sources of PAHs in sediments of the estuary, which were divided into three groups: petrogenic, pyrolytic and mixing of sources. The urban concentration of the Great Natal and the various industrial activities associated with it can be blamed as potential sources of PAHs in bottom sediments of the estuary studied. The data presented highlight the need to control the causes of existing pollution in the estuary

Hidrocarbonetos alifáticos em sedimentos de fundo do estuário do Rio Potengi, grande Natal (RN): implicações ambientais

The Potengi river estuary is located in the region of Natal (RN, Brazil), comprising a population of approximately 1,000,000 inhabitants. Besides the dominant urban presence, the estuary has fragments of mangrove forest. The objective of this study is to determine the aliphatic hydrocarbons found in the bottom sediments of this estuary, identifying their levels, distribution and their possible origins through the diagnostic rates, indexes and results comparisons with the local anthropic and natural characteristics. The samples were obtained according to a plan that allowed sampling of the estuary up to 12 km upstream from it as mounth. 36 stations were selected, grouped into 12 cross sections through the course of the river and spaced on average by 1 km. Each section consisted of three stations: the right margin, the deepest point and the left margin. The hydrocarbon n-alkanes from C10 to C36, the isoprenoids pristane and phytane, the unresolved complex mixture (UCM) and the total resolved hydrocarbons were analyzed by gas chromatography. N-alkanes, pristane, phytane and UCM were detected only at some stations. In the other, the concentration was below the detection limit defined by the analytical method (0.1 mg / kg), preventing them from being analyzed to determine the origin of the material found. By using different parameters, the results show that the estuary receives both the input of petrogenic hydrocarbons, but also of biogenic hydrocarbons, featuring a mixture of sources and relatively impacted portions. Based on the characteristics and activities found in the region, it is possible to affirm that petrogenic sources related to oil products enter the estuary via urban runoff or boats traffic, boat washing and fueling. Turning to the biogenic source, the predominant origin was terrestrial, characterized by vascular plants, indicating contribution of mangrove vegetation. It was evident the presence of, at specific points in the estuary, hydrocarbon pollution, and, therefore is recommended the adoption of actions aimed at interrupting or, at least, mitigating the sources potentially capable of damp petrogenic hydrocarbons in the estuary studied.

Sistema inteligente para estimar a porosidade em sedimentos a partir da análise de sinais GPR

This Thesis presents the elaboration of a methodological propose for the development of an intelligent system, able to automatically achieve the effective porosity, in sedimentary layers, from a data bank built with information from the Ground Penetrating Radar GPR. The intelligent system was built to model the relation between the porosity (response variable) and the electromagnetic attribute from the GPR (explicative variables). Using it, the porosity was estimated using the artificial neural network (Multilayer Perceptron MLP) and the multiple linear regression. The data from the response variable and from the explicative variables were achieved in laboratory and in GPR surveys outlined in controlled sites, on site and in laboratory. The proposed intelligent system has the capacity of estimating the porosity from any available data bank, which has the same variables used in this Thesis. The architecture of the neural network used can be modified according to the existing necessity, adapting to the available data bank. The use of the multiple linear regression model allowed the identification and quantification of the influence (level of effect) from each explicative variable in the estimation of the porosity. The proposed methodology can revolutionize the use of the GPR, not only for the imaging of the sedimentary geometry and faces, but mainly for the automatically achievement of the porosity one of the most important parameters for the characterization of reservoir rocks (from petroleum or water)

Monitoramento da morfologia costeira em setores da bacia potiguar sob influência da indústria petrolífera utilizando geodésia de alta precisão e laser escâner terrestre

The objective of this Doctoral Thesis was monitoring, in trimestral scale, the coastal morphology of the Northeastern coast sections of Rio Grande do Norte State, in Brazil, which is an area of Potiguar Basin influenced by the oil industry activities. The studied sections compose coastal areas with intense sedimentary erosion and high environmental sensitivity to the oil spill. In order to achieve the general objective of this study, the work has been systematized in four steps. The first one refers to the evaluation of the geomorphological data acquisition methodologies used on Digital Elevation Model (DEM) of sandy beaches. The data has been obtained from Soledade beach, located on the Northeastern coast of Rio Grande Norte. The second step has been centered on the increasing of the reference geodetic infrastructure to accomplish the geodetic survey of the studied area by implanting a station in Corta Cachorro Barrier Island and by conducting monitoring geodetic surveys to understand the beach system based on the Coastline (CL) and on DEM multitemporal analysis. The third phase has been related to the usage of the methodology developed by Santos; Amaro (2011) and Santos et al. (2012) for the surveying, processing, representation, integration and analysis of Coastlines from sandy coast, which have been obtained through geodetic techniques of positioning, morphological change analysis and sediment transport. The fourth stage represents the innovation of surveys in coastal environment by using the Terrestrial Laser Scanning (TLS), based on Light Detection and Ranging (LiDAR), to evaluate a highly eroded section on Soledade beach where the oil industry structures are located. The evaluation has been achieved through high-precision DEM and accuracy during the modeling of the coast morphology changes. The result analysis of the integrated study about the spatial and temporal interrelations of the intense coastal processes in areas of building cycles and destruction of beaches has allowed identifying the causes and consequences of the intense coastal erosion in exposed beach sections and in barrier islands

Bioecologia da ictiofauna marinha descartada pelo arrasto camaroeiro em praias da Bacia Potiguar, Brasil

The composition of ichthyofauna discarded by trawling shrimping, their reproductive status and feeding ecology were studied on the beaches of Basin Rio Grande do Norte, Brazil. Fish were collected monthly in the year of 2012. During biometrics, portions of the digestive tract and of gonads were removed, fixed in formalin 10% and Bouin, respectively, for be submitted to histological processing by the techniques of hematoxylin-eosin. Stomach content analyzes were performed using the methods of Frequency of Occurrence and Volumetric and was calculated the repletion index. Throughout the study period were recorded a total of 49 species. The fish assemblages differed between sections monitoring, with the highest abundance, biomass and indices of richness and diversity in sections B, D and C. Already the excerpt A, showed higher values for dominance and equitability. In the cluster analysis according to the faunal similarity was observed the formation of three groups: group I formed by excerpts B and D, group II by excerpt C and group III formed by excerpt A. The assessment of reproductive stage revealed that the fish assemblages discarded by trawling are composed mainly of juveniles. Regarding the feeding ecology, the species Larimus breviceps, Menticirrhus littoralis and Pomadasys corvinaeformis characterized as carnivorous with tendency to carcinofagia. Already Conodon nobilis characterized as carnivorous with tendency to piscivory, but all proved generalist-opportunistic with increase of feeding activity during drought. The dendrogram of grouping of the species developed based on the food items used shows the formation of four groups: Group I consists of species that feed mainly of "gastropod" and "sediment"; group II of "teleost fish"; the group III of "crustacea" and group IV of "echinodermata" and "bivalve". The anatomical and histological characteristics of the digestive tract were consistent with the dietary habits of the analyzed species. In this context, the Costa Branca of Rio Grande do Norte can be considered a feeding site and recruitment for juveniles, which, opportunistically, utilize resources associated with the background

Influência das águas da Bacia Hidrográfica Pirangi na balneabilidade das praias de Pirangi, nos municípios de Nísia Floresta e Parnamirim Rio Grande do Norte, Brasil

The Pirangi beach is located in the eastern coastline of Rio Grande do Norte state, in the municipality of Parnamirim and Nísia Floresta. In it flow into Pirangi Watershed (PW), whose water receives large amounts of pollutants, mainly domestic and industrial sewage from districts where pass the rivers that consist it, compromising, thus, the bathing water quality of the Pirangi beach. Bearing in mind the importance of water sanitary quality to ensure an environment that no present risk to the bathers s health, this work had as main objective to assess the influence of the PW s waters in the bathing water quality of the Pirangi beaches. To that end, were made collections of water in the beaches and in the rivers with the intention of quantify the fecal contamination indicators thermotolerant coliforms and enterococci, to then classify the conditions of bathing water quality according with the CONAMA Resolution number 274 of 2000. For the purposes greater knowledge about the health conditions of the Beaches Pirangi and about the influence the PW s waters exert on it, was done parallely to the study of the water quality, an investigation of the sand sanitary quality. Furthermore, it was made an evaluation of the PW s Water Quality through Water Quality Index (WQI). Starting from the results obtained in the research present was possible to verify, among other aspects, that the entry of the PW s waters in the Pirangi beaches exerts direct influence in the bathing water quality of the same ones, being the North Pirangi beach (point tracking PA-02) the most influenced. There was noticed also a significant reduction in the conditions of bathing water quality of the beaches in the rainy season. However, the precariousness do sewerage system of the Natal metropolitan region and the absence of a right system of treatment an final disposal of domestic sewage and industrial are the main factors responsi le for deterioration of the PW s Water Quality, and as a consequence, compromising the bathing water quality of the Pirangi beaches

Geoquímica de sedimentos de fundo dos rios Trairí, Ararí e da Laguna Nísia Floresta (RN)

The metal concentrations (Al, Ba, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Zn ) and phosforus(P) had been determined analyzed through Plasma Inductively Coupled Plasme Mass Spectrometer for fine fraction, < 0,63 mm in 22 samples. The sample preparation for analysis had been make in the laboratories of geology of the UFRN. This samples procedures consists in register, dry, bolt and send to analysis in external laboratory (LAKEFIELD GEOSOL) in Belo Horizonte (MG, Brazil). The studied area involves the rivers Trairi, Ararí and Nísia Floresta lagoon, that empties in the sea, situated in the Rio Grande do Norte State. The study objects (Rivers Trairí, Ararí and Nísia Floresta lagoon) receive influences from urban dumpies, agrotoxics and fertilizer, shrimps tank, pastoral, with this, the concentrations of metals (Al, Ba, Cd, Cr, Cu, Fe, Mn, Ni, Pb, P, Zn) (except phosforus) in some points of the study area had been above of the value of reference what it leads to classify them as not polluted to moderately polluted, as the calculated Igeo. In front of discussed, can say about the environmental problems found in Trairi, Ararí and Nísia Floresta Lagoon are still in small scale, since when regard the studied área is over human activity effects

Avaliação das condições química e física dos sedimentos do estuário Jundiaí-Potengi

The aim of this study was to quantify the presence of major and minor elements in the sediments of the Jundiaí-Potengi estuary, bordering the municipalities of Macaíba, Natal and São Gonçalo do Amarante in the state of Rio Grande do Norte, Brazil, considering the evidence of anthropic activity along this estuary, resulting in pollution by treated and untreated wastewaters as well as those produced by industry and shrimp farming. The assessment of the environmental status of this estuary was based on physical-chemical parameters, such as granulometry, organic matter and the major (Al, Fe, Mn and P) and minor (Cd, Cr, Cu, Ni, Pb and Zn) elements found in sediment samples. Two collections were made at 12 georeferenced points along the channel of the estuary at different times. Granulometric analysis was carried out and the percentage of organic matter was determined. The sediments were microwave digested using acid digestion and quantitative analyses of the elements Al, Fe, Cd, Cr, Cu, Mn, Ni, P, Pb and Zn were performed by inductively coupled plasma optical emission spectrometry. Sediment analysis followed the methodology proposed by US EPA 3051A for total elements analysis. The small correlation between the organic matter and the elements studied here suggests that they are of geochemical rather than anthropic origin. The analytical results obtained from the bottom sediment samples in the study area show that the concentration of elements was below the reference values for standard shales (Turekian & Wedepohl, 1961) at the vast majority of points analyzed, ruling out a possible contamination by metals

Hidrocarbonetos policíclicos aromáticos no meio ambiente: diferenciação de fontes em sedimentos e metabólitos em bile de peixes

Many studies on environmental ecosystems quality related to polycyclic aromatic hydrocarbons (PAH) have been carried out routinely due to their ubiquotus presence worldwide and to their potential toxicity after its biotransformation. PAH may be introduced into the environmet by natural and anthropogenic processes from direct runoff and discharges and indirect atmospheric deposition. Sources of naturally occurring PAHs include natural fires, natural oil seepage and recent biological or diagenetic processes. Anthropogenic sources of PAHs, acute or chronic, are combustion of organic matter (petroleum, coal, wood), waste and releases/spills of petroleum and derivatives (river runoff, sewage outfalls, maritime transport, pipelines). Besides the co-existence of multiples sources of PAH in the environmental samples, these compounds are subject to many processes that lead to geochemical fates (physical-chemical transformation, biodegradation and photo-oxidation), which leads to an alteration of their composition. All these facts make the identification of the hydrocarbons sources, if petrogenic, pyrolytic or natural, a challenge. One of the objectives of this study is to establish tools to identify the origin of hydrocarbons in environmental samples. PAH diagnostic ratios and PAH principal component analysis were tested on a critical area: Guanabara Bay sediments. Guanabara Bay is located in a complex urban area of Rio de Janeiro with a high anthropogenic influence, being an endpoint of chronic pollution from the Greater Rio and it was the scenario of an acute event of oil release in January 2000. It were quantified 38 compounds, parental and alkylated PAH, in 21 sediment samples collected in two surveys: 2000 and 2003. The PAH levels varied from 400 to 58439 ng g-1. Both tested techniques for origin identification of hydrocarbons have shown their applicability, being able to discriminate the PAH sources for the majority of the samples analysed. The bay sediments were separated into two big clusters: sediments with a clear pattern of petrogenic introduction of hydrocarbons (from intertidal area) and sediments with combustion characteristics (from subtidal region). Only a minority of the samples could not display a clear contribution of petrogenic or pyrolytic input. The diagnostic ratios that have exhibited high ability to distinguish combustion- and petroleum-derived PAH inputs for Guanabara Bay sediments were Phenanthrene+Anthracene/(Phenanthrene+Anthracene+C1Phenanthrene); Fluorantene/(Fluorantene+Pyrene); Σ (other 3-6 ring PAHs)/ Σ (5 alkylated PAH series). The PCA results prooved to be a useful tool for PAH source identification in the environment, corroborating the diagnostic indexes. In relation to the temporal evaluation carried out in this study, it was not verified significant changes on the class of predominant source of the samples. This result indicates that the hydrocarbons present in the Guanabara Bay sediments are mainly related to the long-term anthropogenic input and not directly related to acute events such as the oil spill of January 2000. This findings were similar to various international estuarine sites. Finally, this work had a complementary objective of evaluating the level of hydrocarbons exposure of the aquatic organisms of Guanabara Bay. It was a preliminary study in which a quantification of 12 individual biliar metabolites of PAH was performed in four demersal fish representing three different families. The analysed metabolites were 1-hydroxynaphtalene, 2-hidroxinaphtalene, 1hydroxyphenanthrene, 9-hydroxyphenanthrene, 2-hydroxyphenanthrene, 1hydroxypyrene, 3-hidroxibiphenil, 3- hydroxyphenanthrene, 1-hydroxychrysene, 9hydroxyfluorene, 4-hydroxyphenanthrene, 3-hydroxybenz(a)pyrene. The metabolites concentrations were found to be high, ranging from 13 to 177 µg g-1, however they were similar to worldwide regions under high anthropogenic input. Besides the metabolites established by the used protocol, it was possible to verified high concentrations of three other compounds not yet reported in the literature. They were related to pyrolytic PAH contribution to Guanabara Bay aquatic biota: 1-hydroxypyrine and 3-hydroxybenz(a)pyrine isomers

Alterações ambientais em Parelhas, Rio Grande do Norte: metais pesados em sedimentos de drenagens e percepção de comunidades rurais em relação a mudanças na paisagem

The conservation of natural resources is essential and constitutes the main subject of many researches, which characterize important aspects concerning the environmental alterations in the ground, water, landscape and socioeconomic information. This study aimed to investigate the anthropogenic input of heavy metals in the environment, in the area of the Parelhas dump site and in part of the Seridó River and to determine the concentration of heavy metals in the sediments. This can result in risk to the environment and human health. In addition, we sought to establish the socioeconomic profile of rural communities adjacent to Seridó River and to comprehend the perception of these dwellers about the changes in the places they live. The area of this study is located in the city of Parelhas/RN, in the centralsouthern part of the State, in the micro-region of the Oriental Seridó. This area comprehends the place where the dump site is located, next to RN 086, the Caldeirão dam, the Quintos river called by local citizens Caldeirão creek and part of Seridó river, perpetuated by the Boqueirão dam, which crosses the city and it includes the rural communities of Almas, Domingas, Sussuarana II and Colonos. Regarding the study with bottom sediments, the samples were collected and taken to the laboratory of geochemistry, where they were dried, sieved, weighted and submitted to weak acid attack. The analysis of heavy metals was held by Atomic Absorption Spectrophotometer - Flame AAS. We applied 23 closed questionnaires constituted by 38 questions to collect informations in the rural communities, oriented to establish the socioeconomic profile and the environmental perception of the participants. The participants were distributed in the communities of Almas (1), Domingas (2), Sussuarana II (10) and Colonos (10). Most of them presented similar socioeconomic profiles. They are from 45 to 60 years old and live in these localities for 20 to 30 years or more. The families are composed by 3 or 4 people; the agriculture is the main activity, livestock is the secondary and 48% of them earn the minimal wage. Regarding the environmental perception, the participants can realize some changes in vegetation, soil, water and landscape. People living longer in the community, and with more years of experience on the local reality can perceive the depletion of the soil, pastures and changes in the landscape. These changes portray how the place was previously and what it represents today. The perception of these changes, besides the environmental ones, includes others concerning the increasing number of dwellers in the last years, as well as the number of houses. The changes happened through activities developed by the dwellers over the years, including agricultural practices, livestock, grass planting and even the cultivation of cotton. The study provided the acquisition of new data about the environmental reality of this region. It can subsidize the definition of public policies that can be implemented from the perspective of conservation of water resources and of the coexistence and survival of man in the semi-arid