Evolução morfotectônica do maciço estrutural pereiro, província Borborema

The Northeast relief was described by the Pediplanation Model. This action discards the theoretical basis of post-Cretaceous tectonic evolution of the landscape. Through this model the Massif Pereiro - MP, Borborema Province, was established as part of the Tablelands Area Residual Sertanejos. The present work aims to establish the post- Cretaceous morphotectonic evolution of the MP by geomorphological and geological mapping using Geographic Information System, Remote Sensing and dating of sediments by Single Aliquot Regenerative-dose (SAR). The MP is contained in the core semi-arid, annual precipitation of 600-800 mm / year. The MP is NE-SW, is limited by Shear Zone Jaguaribe (ZCJ) and Portalegre Shear Zone (ZCPa), the same attitude, and crossed by several other shear zones. These shear zones show evidence of brittle Cenozoic reactivation, mostly as normal faults and shallow crustal level. The Quaternary sedimentation around the MP focuses on fault escarpments in a general pattern cascade, where ages decrease from the summits of the steep foothills. The ages of 51 sediment samples indicate a correlation with global climate following pulses: Last Interestadial-UI, the Last Glacial Maximum - LGM and the transition Pleistocene / Holocene, while the latter focus on 18 of 51 samples dated. This study also finds evidence of a new quaternary basin, here called Merejo Basin. Through these results it is concluded that no evidence of post-Cretaceous tectonic evolution of morphological MP, as their retreat along the fault scarps, invariably following the trend of the shear zones. The erosion of cliffs in large time scale is controlled by weakness zones generated by faults on the other hand the erosion of cliffs in short time, with the formation of deposits and colluvial horizons pedogenizados, has climate control. It was also found that in the study area there is a preponderance of past and current tectonic erosion processes on the morphological evolution

Análise de uso e cobertura do solo no município de Parelhas/RN

The human interference in the semiarid region of Seridó Potiguar has promoted the increase of degraded areas. The economic dynamic that was established in the Seridó territory, especially after the fall of the trinomial cattle-cotton-mining in the 70s and 80s of the 20th century as pillars of the regional economy, resulted in an accelerated process of erosion of natural resources. The municipalities of the Seridó region have been spatially reordered by this new economic dynamic, marked by the growth of existing enterprises, and the development of new agricultural practices. One of the municipalities in the region that restructured its territorial space with the emergence of new agro-industrial activities was the town of Parelhas. With the demise of the trinomial cattle-cotton-mining in the 1980s, other productive activities were intensified from the 1990s, amongst them, pottery, responsible for the vegetal extraction for use as energy source. This recent economic and spatial restructuring in the region, reflected in the Parelhense municipal territory, required new productive ingredients responsible for the modification of past production relations that were based on cattle, cotton and mining. By that a process of exploring the environment was unleashed, especially the native vegetation, in an uncontrolled manner. In this context, the objective of this study was to survey and detect deforestation in the areas of Caatinga vegetation, used indiscriminately as energy supply for new agricultural practices, using remote sensing techniques based on the quantification of the Normalized Difference Vegetation Index / NDVI, Soil-Adjusted Vegetation Index / SAVI, surface temperature and rainfall data in the years 1990 and 2010. The results indicated that SAVI values above 0.2 in 1990 and 2010 represent the areas with the highest density of vegetation that occur exclusively along the major drainages in the town and areas of higher elevations. The areas between the ranges of values from 0.5 to 0.15 SAVI are areas with poor vegetation. On the other hand the highest values of temperature are distributed in the western and southeastern parts of the township, usually in places where the soil is exposed or there is sparse vegetation. The areas of bare soil decreased in extension in 2010 at 11, 6% when related to 1990, this was caused by a higher rainfall intensity in the first half of 2010, but no regeneration of vegetation occurred in some places in the western and southeastern areas of the municipality today, due to the extraction of firewood to fuel the furnaces of industries in town

Análise hidrodinâmica e morfodinâmica do complexo estuarino do Rio Piranhas-Açu/RN, Nordeste do Brasil

The aim of this study was the seasonal characterization of the morphology, sedimentology and hydrodynamic of the Açu, Cavalos and Conchas estuaries. These estuaries are inserted in a semi-arid climate area and form the mouth of the hydrographic basin of the Piranhas-Açu river, that represent the discharge of the largest watershed in the state. They are embedded in an environment consisting of a fluvial-marine floodplain, mangrove ecosystem, sandbanks, fields of dunes, spits and sandy beaches. Adjacent to the natural units are the main local socioeconomic activities (oil industry, salt industry, shrimp farming, fishing and tourism) are dependent on this river and its conservation. The environmental monitoring is necessary because it is an area under constant action of coastal processes and at high risk of oil spill. The acquisition and interpretation of hydrodynamic, sonographic and sediment data was conducted in two campaigns, dry season (2010) and rainy season (2011), using respectively the current profiler ADCP Doppler effect, the side-scan sonar and Van Veen sampler. In these estuaries: Açu, Cavalos and Conchas were identified the following types of bedforms: flatbed and Dunes 2-D and 3-D (small to medium size), generated at lower flow regime (Froude number <1). Structures such as ripples were observed in the Açu estuary mouth. The higher values of flow discharge and velocity were recorded in the Açu estuary (434,992 m³.s-¹ and 0,554 m.s-¹). In rainy season, despite the record of highest values of discharge and flow velocities at the mouth, the energy rates upstream did not differ much from the data of the dry season. However, in all estuaries were recorded an increase in speed and flow, with reservation to the flow in the Açu estuary and flow at the mouth of the Conchas estuary. Sediment grain sizes tend to increase towards the mouth of the estuary and these ranged from very fine sand to very coarse sand, medium sand fraction being the most recurrent. Based on the data acquired and analyzed, the estuaries Açu, Cavalos and Conchas are classified as mixed , dominated by waves and tides. According to their morphology, they are classified as estuaries constructed by bar and according to the classification by salinity, estuaries Conchas and Cavalos were ranked as hypersaline estuaries, and Açu as hypersaline and vertically well mixed type C

Fragilidade ambiental da bacia hidrográfica do Rio Seridó (RN/PB Brasil)

There are many applications coming from geomorphological studies and their different constitutive and inter related elements, to the implementation of public politics of planning and environmental management. This search presents an analysis of the environmental fragility of the watershed of Seridó River, situated between the states of Paraíba and Rio Grande do Norte (Brazil), including the identification of possible unstable areas. It is based on the methodological approach of Ecodynamics of the French researcher J. Tricart (1977) and on the operalisation proposal advocated by the Brazilian J. Ross (1994), related to the Potential and Emerging Ecodynamic Units, grounded in the Relief s Dissection Index or the topographic roughness, soil, rainfall and land use/vegetal cover. Under a quantitative perspective, the results obtained from the analysis of the watershed can be divided into classes of potential fragility: around 2.613,0 km² of low intensity, 5.188,4 km² of medium intensity and 2.585,5 km² of high intensity. Concerning the emerging fragility, the results are close to 2.212,0 km² of low intensity, 6.191,23 km² of medium intensity and 2.062,34 km² of high intensity. In the case of the watershed in question, the environmental degradation is particularly effective in the areas more dissected, where the ecological conditions, in synergy the environmental degradation, prevent the regeneration of vegetation when arises an opportunity for the (re)establishment of its equilibrium tenuous. The collected data is relevant for the territorial and environmental planning of the watershed, once we can still verify a close association of the cities on the central area of desertification with the areas of high environmental instability/fragility. This is an important tool to the understanding of the potential susceptibility of the natural and anthropic environments related to the advance and/or intensification of the erosion process, rock falls, mass movements, among other phenomena inside the potential unstable areas. From this perspective, the continuity of this research becomes extremely important to the understanding and arrangement of the process, together with the engendering and sustainability of the system in its totality; in narrow correlation because their potentialities, constraints and alternatives on Seridó River watershed, and in all the semi-arid region with similar characteristics

A comunidade zooplanctônica como bioindicadora do estado trófico de reservatórios da região semiárida tropical

E utrophication in continental aquatic ecosystems and the following deterioration of water quality are some of the greatest problems to be solved in this century. Due to their own peculiarities reservoirs from semi - arid regions constitute a great challenge to water management because of their greater vulnerability to eutrophication process. I dentification of biolo gical community components that may be used as bioindicators is important to allow an early detection of adverse changes, and also to provide subsidies for management and conservation actions. The aim of the present study is to evaluate the potential of zo oplankton community as bioindicator of the trophic state of two reservoirs belonging to the Piranhas - Açu basin, RN, Brazil: Boqueirão de Parelhas and Passagem das Traíras. Monthly sampling s of both systems were carried out in both systems during the period of January to December. Measurements were performed for temperature, pH, dissolved oxygen and water electrical conductivity besides water samples collection for nutrients, suspended solids, chlorophyll - a and zooplankton analyses. T axonomic composition of zooplankton , density and biomass were analysed. Trophic state index, ABC curves , W statistic and the Calanoida: Cyclopoida ratio were also obtained. The results evidenced that Boqueirão de Parelhas reservoir was a mesotrophic sy stem, and Passagem das Traíras r eservoir was eutrophic. In both reservoirs zooplankton community had low species richness, mostly constituted by tolerant species which have wide geographical distribution, as well the dominance of the rotifers Brachionus havanaensis , B. calyciflo rus and Keratella tropica ; of the calanoid copepods Notodiaptomus cearensis and N. iheringi ; cyclopoid copepod Thermocyclops decipiens, and of the cladocerans Ceriodaphnia cornuta and Diaphanosoma spinulosum . Among the biological indices the ABC curves fo r the zooplankton community indicated a moderate dis turbance in both reservoirs, th e Calanoida: Cyclopoida ration indicated not impacted environments , e xcept during the end of the study to the reservoir Passagem das Traíras . It was concluded that the indices used are good indicators of disturbance and alteration in the community, however they are not good indicators for monitoring the trophic state of the studied reservoirs due to the simultaneous occurrence of other factors selecting species, as the c oncentration of ions and high turbidity, which are part of the reservoir characteristics of semiarid.

Qualidade do solo da camada de cobertura final em área de disposição de resíduos no semiárido tropical

The final disposal of municipal solid waste in unsuitable areas without an infrastructure that meets the health measures and environmental protection, coupled with the lack of technical criteria in phase and decommissioning of the dump can promote environmental degradation. Alternatively to minimize the impacts of this activity for the stabilization of the area by isolating the massive waste with implementation of an adequate and finished by a layer of soil for plant growth final cover system. In this context, the present study aimed to evaluate the quality of the final cover in the area of a disabled dump the tropical semi-arid region in order to assist the process of recovery of these areas. The study area is located in the tropical semi-arid region in São João do Sabugi /RN. Soil samples were collected in the dump area and bushland as a benchmark of quality. To which they were subjected to analysis of physical attributes (particle density, bulk density, grain size and porosity), chemical properties (pH, K + , Na+ , Ca2 + , Mg2 + and Al3 + exchangeable, potential acidity, available phosphorus, sum of bases, CEC, base saturation, aluminum saturation, saturation Na + and adsorption ratio sodium, total organic carbon and total nitrogen) and total and soluble concentrations of heavy metals (Mn, Pb, Zn, Cd, Cu, Mo, Co, Cr, Ba and Ni). The differences between physical and chemical soil under native forest and final cover showing reduction of soil quality in the area off to the dump, which hinders the development of native vegetation and the recovery of the area. The absence of superior waterproofing to allow vertical transfer between the solid waste and the final cover promoted enrichment by chemical elements and heavy metals in excess can impair revegetation. Deficiencies found in the construction process of the final cover point to the need for intervention to accelerate the process of stabilization and recovery of the area of the local ecosystem

Alterações morfofisiológicas e moleculares em resposta a estresses abióticos em mamona (Ricinus communis L.)

The use of fossil fuels has been considered one of reason for the increase of pollution in the atmosphere and it may be related to the climate changes. Then, the research of the new sources of fuels will be important. Considering this, the use of biodiesel has been considered not as bad as petrol. The castor bean (Ricinus communis L.) is an important oilseed, which belongs to Euphorbiaceae family, and the oil found in the seed has important characteristics for biodiesel. This plant is considered as “rustic” as it does not need so much water for its development and oil production. Due to this, this plant has been considered to be ideal in semi-arid regions, such as the Northeast of Brazil. The aim of his study is to better understand the responses to abiotic stresses (drought and salinity) from castor bean plants using morphological, physiological and molecular tools. In order to do this, the castor bean plants were subjected to salt stress (50, 100, 150 and 200 mM NaCl) in a controlled environment and drought stress (5, 10, 15 days and 10 days cyclic). After these treatments, these plants were subjected to different analyzes: a) the expansion and retention of water from leaves; b) anatomy using leaves and roots. Based on these results, we found that castor suffered decrease in leaf area with increase drought stress, however restricted water loss, probably by accumulation of compatible solutes in the leaves. The anatomy data showed modifications in the vascular system. These modifications observed suggested that castor bean plant may be resistant to stress as it was verified in 5 days of drought as well as in 100 mM NaCl. In both conditions, these plants were fine. Probably these plants keep some solutes in the cell and then maintain the cell tugor. The data obtained in this study gave a better idea how castor bean plant responds to abiotic stress conditions - drought and salt stress

Gestão de recursos hídricos: governança e gerenciamento de conflitos pelo uso da água em região do Semiárido Nordestino

The water being vital natural resource and factor of economic and social development requires effective management and protection by the State. This thesis examines the panorama of National Water Resources Policy and the establishment of an effectively integrated management, shared and participative, contextualizing the principles foreseen in the policy. The work is focused on the discussion of public policies of access to water, analyzing the Fresh Water Program in semi-arid region of Brazil as a strategy of coexistence and permanence of a public policy that ensures the priority use, which is for human consumption. The conceptual framework of this study relies primarily on the contributions of authors in the field recognized as governance and water management. A study on the process of implementation of the various "institutions and policies" related to water management was promoted, contextualizing the change of paradigm in the transition from the centralized model to the one that takes into account the social participation, opening in this way broader perspectives for the analysis of the contents and of the impacts of these policies. The development of this study was conducted by the follow-up – both face-to-face as documentary-field – of the activities carried out while consultant of the Fresh Water Program. The history of water management in the semi-arid region was studied, depicting conflict movements and cooperation among actors. Despite the great obstacles to accomplish the shared and decentralized management, the study of this thesis points to a gradual improvement in the formulation of public policies that take into consideration governance and participatory management of water resources, with positive prospects towards the implementation of coordinated and cooperative actions in the region that mainly suffers from the shortage of rainfall, hence of shortage of water for irrigation and human consumption

Avaliação de usabilidade em materiais interativos de ensino a distância da UFRN-SEDIS

This study aims to assess the usability of Interactive Materials developed for the courses offered by UFRN SEDIS the modality of distance education (DE), using the techniques of focus group cooperative evaluation and assessment of satisfaction. The Interactive Materials are intended to serve as an avenue where the course content reaches the student in an educational, stimulating and self-instructive enough for the student to engage and find no difficulty in using it so. After the survey data in this context were selected four Interactive Materials ("Introduction to Applied Calculus", "Science, Technology and Society", "studies the Semi-Arid" and "Cultural Geography") that adopt the framework established by UFRN for SEDIS be evaluated for their usability. Initially, a preliminary test was conducted from cooperative assessment with a student interacting with the four learning objects in order to reveal and map the major failures of usability, supporting deeper questions later. The recordings of this preliminary test were analyzed by a focus group composed of two graphic designers and two multimedia designers, and developers responsible for these objects, which helped to analyze the gap between "what was designed" and "as was used "structuring and supplementing the roadmap for cooperative evaluation and assessment of subsequent satisfaction. The cooperative evaluation was applied individually to ten students of undergraduate UFRN that tested each of the four materials. At the end, every student completed a questionnaire assessing satisfaction form adapted Wanted (Questionnaire for User Interaction Satisfaction). The analysis of the data collected in this study revealed positive, negative and notes to be considered to guide the future development of Interactive Materials, in the context of UFRN SEDIS, feedback to the process of design and evaluation with user participation

Estimativa do fluxo de calor e da difusividade térmica do solo, baseado na solução da derivada temporal fracionária de meia ordem em ferramenta de software

The soil heat flux and soil thermal diffusivity are important components of the surface energy balance, especially in ar id and semi-arid regions. The obj ective of this work was to carry out to estimate the soil heat flux from th e soil temperature measured at a single depth, based on the half-order time derivative met hod proposed by Wang and Bras (1999), and to establish a method capable of es timating the thermal diffusivity of the soil, based on the half order derivative, from the temporal series of soil temperature at two depths. The results obtained in the estimates of soil heat flux were compared with the values of soil heat flux measured through flux plates, and the thermal di ffusivity estimated was compared with the measurements carried out in situ. The results obtained showed excellent concordance between the estimated and measured soil heat flux, with correlation (r), coeffici ent of determination (R 2 ) and standard error (W/m 2 ) of: r = 0.99093, R 2 = 0.98194 and error = 2.56 (W/m 2 ) for estimated period of 10 days; r = 0,99069, R 2 = 0,98147 and error = 2.59 (W/m 2 ) for estimated period of 30 days; and r = 0,98974, R 2 = 0,97958 and error = 2.77 (W/m 2 ) for estimated period of 120 days. The values of thermal di ffusivity estimated by the proposed method showed to be coherent and consis tent with in situ measured va lues, and with the values found in the literature usi ng conventional methods.

Modelos de dispersão para extremos de precipitação. Estudo de caso: o nordeste do Brasil

In this thesis used four different methods in order to diagnose the precipitation extremes on Northeastern Brazil (NEB): Generalized Linear Model s via logistic regression and Poisson, extreme value theory analysis via generalized extre me value (GEV) and generalized Pareto (GPD) distributions and Vectorial Generalized Linea r Models via GEV (MVLG GEV). The logistic regression and Poisson models were used to identify the interactions between the precipitation extremes and other variables based on the odds ratios and relative risks. It was found that the outgoing longwave radiation was the indicator variable for the occurrence of extreme precipitation on eastern, northern and semi arid NEB, and the relative humidity was verified on southern NEB. The GEV and GPD distribut ions (based on the 95th percentile) showed that the location and scale parameters were presented the maximum on the eastern and northern coast NEB, the GEV verified a maximum core on western of Pernambuco influenced by weather systems and topography. The GEV and GPD shape parameter, for most regions the data fitted by Weibull negative an d Beta distributions (ξ < 0) , respectively. The levels and return periods of GEV (GPD) on north ern Maranhão (centerrn of Bahia) may occur at least an extreme precipitation event excee ding over of 160.9 mm /day (192.3 mm / day) on next 30 years. The MVLG GEV model found tha t the zonal and meridional wind components, evaporation and Atlantic and Pacific se a surface temperature boost the precipitation extremes. The GEV parameters show the following results: a) location ( ), the highest value was 88.26 ± 6.42 mm on northern Maran hão; b) scale ( σ ), most regions showed positive values, except on southern of Maranhão; an d c) shape ( ξ ), most of the selected regions were adjusted by the Weibull negative distr ibution ( ξ < 0 ). The southern Maranhão and southern Bahia have greater accuracy. The level period, it was estimated that the centern of Bahia may occur at least an extreme precipitatio n event equal to or exceeding over 571.2 mm/day on next 30 years.

Obtenção e conservação de espermatozoides de cutia (Dasyprocta leporina Linneaus, 1753) do semiárido brasileiro

The general objective of this thesis was to stablish protocols to obtain and conserve agouti (Dasyprocta leporina) sperm bred in captivity in the Brazilian semi-arid, aiming its sustainable production. The thesis was divided in three experiments. In the first one, we studied the influence of the interaction between two probes (quadratics and sine waves) and two stimulation protocols (continuous and in series) on the agouti sperm collection by electroejaculation efficiency. The most efficient interaction on this obtainment was the one with probes with rings associated with stimuli in series (4/7; 57%, P<0.05). In the second experiment we compared the cryoprotectant effects of different substances (glycerol, ethyleneglycol, dimethylsulfoxide, dimethylformamide) on epididymis sperm cryopreservation. The highest values on motility (39.5±4.6%), vigor (2.9±0.2) and membrane integrity (30.6±4.5%) were observed on the samples cryopreserved using glycerol when compared to those with ethyleneglycol and dimethylformamide, but there was no difference (P>0.05) when compared to the samples cryopreserved with dimethylsulfoxide. At last, we studied the effects of the methods to obtain sperm (electroejaculation vs epididymal collection) on post thawing sperm quality. The samples obtained by epididymal retrograde flushing showed values for motility of 25.0±10.9% and vigor 2.4±0.8, and those obtained by electroejaculation had 31.2±14.2% of motility and vigor of 2.2±0.7, however, without statistical difference (P>0.05), which shows the possibility to successfully use the epididymal sperm cryopreservation protocol on agouti ejaculated sperm. In conclusion, significant advances on obtainment and processing of agouti sperm were made, allowing the establishment of germplasm banks from sperm samples obtained from the epididymis or by electroejaculation.

Herpetofauna associada à bromélia rupícola, encholirium spectabile, no semiárido brasileiro: revisão da literatura, ecologia das espécies e comportamento de psychosaura agmosticha (squamata: mabuyidae)

Bromeliads are an important microhabitat for the herpetofauna, for being widely used as refuge from predators and their leaf architecture allows humidity maintenance and relatively constant temperature inside, setting a favorable environment for amphibians and reptiles, especially in areas under hydric stress. However, studies addressing this relationship are still incipient and more concentrated in fitotelmatas bromeliad. For non-fitotelmatas rupicolous bromeliads of the gender Encholirium, which develops into rocky outcrops and contains species of semi-arid regions such as the Caatinga, animal-plant relationships are almost unknown. In this context, this study aimed to know the herpetological fauna inhabitant of macambiras bromeliads, Encholirium spectabile, analyzing occupation and use of these bromeliads by different taxa, and the behavioral ecology of the lizard Psychosaura agmosticha, seeking to identify factors associated with this strict relationship in Caatinga. An extensive review of the world literature on the subject “lizards in bromeliads” subsidized this study from the ecological perspective of this association. The field work was carried out at Fazenda Tanques, municipality of Santa Maria / RN, mesoregion of Agreste Potiguar. The observations and/or data collection in daytime and in the evening was conducted monthly during three consecutive days, from January 2011 to August 2012, totaling 450 hour.man of sampling effort. Sixteen species were registered: six lizards (Mabuyidae, Tropiduridae, Gekkonidae and Phyllodactylidae Families), six snakes (Boidae and Dipsadidae Families) and four of amphibians of Hylidae Family. The effect of the forest edge on the distribution of species along the outcrop was significant, with most species found in outcrop edges. Significant difference was found between some pairs of species concerning use of bromeliads, and almost total niche overlap in the use of microhabitat. 62.5% of the species are nocturnal and use these plants for sheltering, breeding and feeding. Regarding the relations between 4 the lizard Psychosaura agmosticha and macambiras bromeliads, behaviors of thermoregulation and foraging in the dry and wet seasons were recorded. Activity periods were concentrated between 7 and 10 am and between 3 and 5 pm in both seasons, showing a clear bimodal pattern. The species basically used the green leaves and there were no significant differences between males and females in the use of bromeliads. Positive associations were found between body temperature and temperatures of bromeliads and air. This species spent 1.95% ± 3.8 of the time moving (PTM) and moved on average 0:36 ± 2.1 seconds per minute (MPM), with significant differences between the wet and dry to PTM, and between the average time of stop and average duration of movements, being considered a sedentary forager. Psychosaura agmosticha, in the study area, is bromelicolous and uses macambiras primarily for thermoregulation and foraging. The results of this study elevate the rupicolous bromeliads Encholirium spectabile as key elements for the maintenance of amphibians and reptiles associated with it, and a clear advantageous association for the conservation of the groups involved.

A biotecnologia na propagação e conservação do umbuzeiro (Spondias tuberosa Arr. Cam.) e percepção sobre sua importância por agricultores da comunidade Malhada Vermelha, Campo Redondo (RN-Brasil)

The umbu tree (Spondias tuberosa Arruda) is a fruit native to the northeast of Brazil with great economic, social and ecological importance for the northeastern semi-arid region. Despite its role, the umbu tree has suffered negative pressure thanks to cluttered extractivism and to negative selection of its fruits, which as the deforestation and the dormancy of seeds contribute to the decrease of its production year after year, making necessary studies that contribute to the improvement of this specie and its conservation. Given the risks to the conservation of the specie and its usefulness to the population, the association between plant biotechnology, for being a tool that can be used to increase its production. and the perception of gathering communities, by valuing the point of view and the knowledge of the population, can facilitate its conservation. This work aimed to develop methods of propagation for umbu tree as well as contribute to its conservation by using biotechnology, with specific objectives to contribute to the conservation of this species; determine concentrations of BAP and ANA in the formation of buds; testing the efficiency of different substrates and concentrations of gibberellic acid on germination in vitro and ex vitro, as well as capture the perception of families in communities that engage in the gathering of umbu. To study the germination, the seeds were inoculated in different substrates (vermiculite, vermiculite + clay, clay, clay + manure and manure + vermiculite) and in different concentrations of gibberellic acid (0 mg, 250 g and 500 mg). For the formation of buds BAP to 0.1 mg-1 was associated with different concentrations of ANA (0.2; 0.4; 0.8mg.L-1). The study of perception was conducted by applying semi-structured questionnaire with Malhada Vermelha community. The experiments resulted in vermiculite and concentration of 500 mg gibberellic acid as the best for germination. The association of 0.1 mg.L-1 of BAP to 0.2 mg.L-1 of ANA provided better formation of buds. As to the application of questionnaires, they revealed that the population understands the decreased amount of umbu plants and umbu fruit in the region, as well as shows concern for its conservation.

Entre rios e ruas: água, açude e tragédia em uma cidade do agreste potiguar (Santa Cruz, 1º de abril de 1981)

On the evening of April 1, 1981, the city of Santa Cruz was taken by a flood that destroyed the spillway weir Santa Cruz and much of the city, causing the population of the lower areas to abandon their homes. Residences and closest to the dam, the river and the creek Trairi Sin streets were totally affected, and many of the houses and public buildings completely destroyed. Located in the state of Rio Grande do Norte, the city of Santa Cruz is marked by a very hot climate and semi-arid. With an average normal rainfall of 498.7 mm per year, the city is affected by drought since the beginning of its foundation, around the year 1831. For its development had continued, it was necessary that the population actualize various environmental interventions Nature, especially as regards the storage and distribution of water. Considering the process of occupying the space in question, as well as the relationships that human groups have with the natural environment, we aim to analyze how human interventions affect the environment around them, modifying it to meet their needs and interests. Thus, we intend to understand how media coverage enabled the construction of a framework of tragedy. We intend to observe how the occupation of Santa Cruz led to the modification of their surroundings, trying to discuss the effects of human intervention on natural disasters. Among the research sources include newspapers A República, Diário de Natal, Tribuna do Norte, O Poti and Folha de São Paulo, as well as interviews with the then mayor of Santa Cruz, Hildebrando Teixeira de Souza, and with the couple José Henrique de Pontes and Severina Aguida de Pontes, whose house was hit by the flood. We will also take messages from the state government, the minutes of the city council of Santa Cruz and reports produced by DNOCS on the construction of the weir and its survey after the flood.