Etnobotânica e percepção ambiental de pescadores e coletoras tradicionais submetidos à escassez de recursos vegetais silvestres

In our first chapter was recorded the perception of fishermen and gatherers of Patané about the absence of local forests, was collected a list of species considered locally as strategic use, the ethnoknowledge associated with those, and identify which of these plants are already perceived as scarce in the region. In the second chapter, was studied all species of plants known by the community, the associated knowledge and the various uses. Were used individual interviews, formal and semi-structured, that have been consecutively applied to sampled respondents not probabilistically by snowball. Were collected socioeconomic data of informants. A adequacy test was performed. Guided tours were conducted to gather photographs and samples witnesses of plants, all identified by the usual methods of botany. Excerpts of the interviews on perceptions appear by looking for consensual information. Some data were presented by descriptive statistics. Were mounted two lists of plants, one with the strategic use and one with all the species listed in the study. It was shown that knowledge about plants remains resilient despite the forest resources now no longer be available.

Gestão e gerenciamento de resíduos sólidos: diretrizes jurídico-ambientais para a sustentabilidade

rates in the Brazilian cities, which time there is an inexistent theoretical reflection about public policy statement adding the way of Urban Solid Waste (USW) and tailing integrated management plans in the majorly Brazilian cities. The unappropriated solid waste disposal and final pollution result in a strong socioenvironmental problems and material extravagancies that should be used to recycling and reusing waste material, besides bringing immense challenges for the thematic Strategy Urban and Environmental Management it considers the Sustainable City Model. Moreover, this labor projects a discussion about USW problematic through legally and environmentally point of view, including the public environmental policy and the social technologies as resolution tactics. At that time, it reports rights, scientific articles, documents and Environmental Law Doctrine on findings thematic studies, also the propose displays an interdisciplinary research methodology which combines bibliographic method - focusing theory aspects of the legally environmentally guiding principle, public policy and social technologies. Those are theorist features very important to create a Municipal Integrated Solid Waste Management Plan (PMGIRS) - modus operandi of the Federal Law n. 12.305/2010 (National Solid Waste Policy - PNRS). That policy is interesting to receive financial resources from federal government (Cities Ministry; idem, Federal Decree n. 7.404/2010 and Federal Law n. 10.257/2001) helping the preservation of the environment, regional development, generation of jobs and income (art. 6º), in addition broadening spreading’s private companies dedicated to waste management. Consequently, the PNRS contains a set of guidelines and general procedures; it should be an operation of this legal policy contextualized by Social Technologies theory (TS) into social issues, legal, economic and environmental aspects. Therefore, this research notes the possibility of public policy statement implementation over and done with the PNRS by the terms of development and sustainability in the urban space.

Caracterização estrutural e atividades farmacológicas do alginato obtido da alga Dictyopteris delicatula (J.V. Lamouroux., 1809) e seu derivado sulfatado

Marine algae are rich sources of various structural compounds which recently has been increasingly studied as a new source of bioactive substances. The alginate, as come as fucans, are considered the main acidic polysaccharides found in brown seaweed. This molecule consists a linear natural polysaccharide, non-sulfated, and presents monosaccharides: acid β-D-mannuronic (M) and α-L-guluronic acid (G); in a vast amount compositions and threads. Alginate has been widely applied in food and pharmaceutical industries because of its ability to retain water, forming films and gels as well as thickening, stabilizing and form emulsions. In this work we aimed to extract, structurally characterize, compare and analyze the possible pharmacological activities of native alginate molecule obtained from brown seaweed Dyctiopteris delicatula (DYN), and its chemically sulfated derivative (DYS). The alginate structure and composition molecule can be proven through chemical dosing, that showed low protein contamination and high sugar level, existence and separation of M and G blocks in the descending paper chromatography, infrared spectroscopy and nuclear magnetic resonance. Molecule sulfation was proven with sulphate dosage, resulting in 28.56% sulphate in molecule; electrophoresis, verify metachromasia with toluidine blue; and infrared spectroscopy, that showed a characteristic band at 1221cm-1 corresponding a sulfate group vibration. For the pharmacological activities the tests was: antioxidant activity, changes in cell function (MTT test) and anticoagulant test. In the antioxidant activity we observed that DYN showed better results in the kidnapping of hydroxyl radicals and ferric chelation compared to DYS, this had the best result in the total antioxidant capacity. Both showed similar activity in reducing power and the kidnapping radicals DPPH. In MTT test DYN and DYS had not proliferative and cytotoxic activity in fibroblast cells (3T3) and showed antiproliferative and cytotoxic activity in cancer cell lines HeLa and B16 melanoma. In anticoagulant assay DYN showed good activity in the intrinsic pathway of blood coagulation, and a small activity in the extrinsic pathway, in the other hand DYS showed only a very small activity in the extrinsic pathway, but cannot come to be regarded as an anticoagulant agent. From these results it can be concluded that the alginate was extracted and sulfated, revealing a potential compound to be used in the pharmaceutical industry as an anticoagulant agent, antioxidant and antitumor and the sulfation has not been conclusively important to performance in the tested pharmacological activities

Receptores de citocinas proinflamatórias na pré-eclâmpsia

Preeclampsia is a disease specific of human pregnancy that affects 3-8% of pregnant women, and it is one of the three leading causes of maternal mortality and morbidity. The disease is characterized by hypertension and proteinuria after the 20th week of gestation. The risk factors for this disease are not completely understood but appear to include dysregulation of the immune response arising from defects in placentation, environmental and genetic factors. This study aimed to determine whether the variation in the amount of proinflammatory cytokine receptors IL-1R2, IL-6R and TNF-αR1 would be involved in preeclampsia. They were recruited women with preeclampsia (n=24) and women who evolved during pregnancy without changes in blood pressure (n=12) were recruited. Clinical and laboratory data were collected. The cytokine receptors (IL-1R2, TNF-αR1 and IL-6R) were assessed in mononuclear cells isolated from peripheral blood using flow cytometry (Control = 8; PE = 24). C-reactive protein (CRP) was determined by CRP ultrasensitive method (Control = 7; PE = 18) was performed using sera pregnant women. Women with preeclampsia had higher weight at the beginning of the pregnancy (p=0.0171) and lower gestational age at delivery (0.0008). Classical monocytes were decreased in preeclampsia but not intermediate or non-classical monocytes. The frequency of IL-1R2 pro inflammatory cytokine receptors is decreased in women with PE only in the subpopulation of non-classical monocytes (p = 0.0011). TNF-αR1 receptor and IL-6R, had a decreased frequency in the three subpopulations of monocyte (classic, intermediate and non-classical) when compared to women with normal pregnancy. An increase in IL-1R2 receptor in TCD4+ lymphocytes, but a decrease in TNF-receptor and IL-6R in women with preeclampsia were found. No differences in the frequency of those receptors in CD3+/CD8+ in preeclampsia. There was no difference in C-reactive protein in preeclampsia. The reduction in the amount of IL-1R2, TNF- αR1 and IL-6R monocytes and lymphocytes can be involved in the regulation of inflammation observed in preeclampsia, contributing to disease.

Áreas importantes para a conservação do último grande herbívoro da caatinga potiguar: o veado-catingueiro (Mazama gouazoubira)

Cervídeo Mazama gouazoubira é a espécie de veado que possui maior distribuição dentre as espécies sul americanas. Aspectos da vegetação, predação, competição, caça e perda de habitat são fatores importantes para compreender a distribuição espacial de herbívoros na paisagem. Dessa forma, considerando a falta de estudos de mamíferos de médio e grande porte na Caatinga, objetivamos compreender quais os fatores ambientais e antrópicos que influenciam a ocupação do veado-catingueiro (M. gouazoubira) na região semiárida do estado do Rio Grande do Norte, Brasil. O estudo foi realizado em 10 áreas amostrais e utilizamos armadilhas fotográficas para amostragem e modelos de ocupação foram construídos representando nossas hipóteses biológicas. Os modelos foram ranqueados através dos valores obtidos do AIC. As variáveis cobertura vegetal de caatinga e densidade da vegetação mostraram maior efeito, já a caatinga arbórea mostrou um efeito menor, sugerindo que a espécie é altamente dependente da vegetação para ocorrer, possuindo menor dependência de caatinga arbórea. Esperamos que nossos resultados possam ser utilizados como suporte para planos de manejo e criação de novas unidades de conservação no estado.

A paisagem da Mata Atlântica do estado do Rio Grande do Norte: remanescentes, configuração espacial e disponibilidade de habitat

The Atlantic Forest in Rio Grande do Norte (RN) is included in Pernambuco biogeographic sub-region and it is composed by Semi-deciduous Forest, deciduous Forest, Mangrove and Restinga. We assessed the conservation status of Atlantic Forest in the RN through remnants mapping using high resolution satellite images and landscape ecology approaches. We evaluated if there is difference between the north and south coastal regions considering their natural a historical land use differences. We also assessed the influence of the small remnants on landscape cover and configuration. The proportion of the original biome area with remnants larger than 3 hectares is 15.60% for the official governmental limit and is 16.60% for the alternative limit (SNE, 2002). This remnants proportion varies between 0.56 and 46.52% in the hydrographic basins. 89.70% of the remnants are smaller than 50 hectares. Only 6.00% of the remnants are greater than 100 hectares, and these remnants are responsible by 65% of remaining area. The patches with smaller area influence all calculated metrics. The south coastal hydrographic basins have higher percentage of coverage of remnants, larger patch densities and fragments with larger areas than north coastal hydrographic basins. The diffuse drainage basins of the southern coastal have the highest percentage of coverage with remnants. 18.28% and 10% of the biome area are protected by reserves, according to the official governmental and alternative limits respectively. The reserves are mainly of sustainable use (IUCN V-VI). Therefore, the Atlantic Forest in Rio Grande do Norte is in critical situation, with low proportion of remaining area and high fragmentation level. It’s indispensable to biome conservation keep all the remaining area, especially the large remnants, and restore areas to increase remnants proportion and to increase landscape connectivity

Caracterização do material particulado e avaliação do risco ocupacional e mecanismos moleculares associados à queima artesanal da castanha de caju

Brazil is among the largest cashew nut producers of the world. However, the roasting process is still carried out artisanally, especially in the Brazilian semiarid region. In face of this occupational problem, the aim of this study was to perform a physical-chemical characterization of the particulate matter (PM) emitted by the roasting of cashew nuts, as well as to determine the occupational risk and molecular mechanisms associated. The most evident PM characteristics were the prevalence of fine particles, typical biomass burning morphologies such as tar ball and the presence of the elements K, Cl, S, Ca and Fe. In addition, atmospheric modeling analyses suggest that these particles can reach neighboring regions of the emission source. Polycyclic aromatic hydrocarbons (PAHs) with carcinogenic potential, such as benzo[a]pyrene, dibenz[a,h]anthracene, benzo[a]anthracene, benzo[b]fluoranthene, chrysene, benzo[k]fluoranthene, indeno[1,2,3-c,d]pyrene and benzo[j]fluoranthene were the most abundant PAHs found in the two air monitoring campaigns. Among the identified oxy-PAH the benzanthrone (7H-benz[d,e]anthracen-7-one) had the highest concentration and the evaluation of lifetime cancer risk showed an increase of 12 to 37 cases of cancer for every 10,000 exposed people. Chemical analysis of roasted cashew nuts identified the PAHs: phenanthrene, benzo[g,h,i]perylene, pyrene and benzo[a]pyrene, besides the 3-pentadecilfenol allergen (urushiol analogue) as prevalent. Occupational exposure to PAHs was confirmed by the increase of urinary 1-hydroxypyrene levels and genotoxic effects were evidenced by the increase on micronuclei and nuclear bud frequency in exfoliated buccal mucosa cells among the exposed workers. Other biomarkers of effects such as karyorrhexis, pyknotic, karyolytic, condensed chromatin and binucleated cells also have their frequencies increased when compared to an unexposed control group. The investigation of the molecular mechanisms associated with the PM organic extract showed cytotoxicity in human lung cell lines (A549) at concentrations ≥ 4 nM BaPeq. Using non-cytotoxic doses the extract was able to activate proteins involved in the DNA damage response pathway (Chk1 and p53). Moreover, the specific contribution of the four most representative PAHs in the cashew nut roasting sample showed that benzo[a]pyrene was the most efficient to activate Chk1 and p53. Finally, the organic extract was able to increase persistently the mRNA expression involved in the PAHs metabolism (CYP1A1 and CYP1B1), inflammatory response (IL-8 and TNF-α) and cell cycle arrest (CDKN1A) for DNA repair (DDB2). The high PM concentrations and its biological effects associated warn of the serious harmful effects of artisanal cashew nut roasting and urgent actions should be taken to the sustainable development of this activity.

Caracterização do material particulado e avaliação do risco ocupacional e mecanismos moleculares associados à queima artesanal da castanha de caju

Brazil is among the largest cashew nut producers of the world. However, the roasting process is still carried out artisanally, especially in the Brazilian semiarid region. In face of this occupational problem, the aim of this study was to perform a physical-chemical characterization of the particulate matter (PM) emitted by the roasting of cashew nuts, as well as to determine the occupational risk and molecular mechanisms associated. The most evident PM characteristics were the prevalence of fine particles, typical biomass burning morphologies such as tar ball and the presence of the elements K, Cl, S, Ca and Fe. In addition, atmospheric modeling analyses suggest that these particles can reach neighboring regions of the emission source. Polycyclic aromatic hydrocarbons (PAHs) with carcinogenic potential, such as benzo[a]pyrene, dibenz[a,h]anthracene, benzo[a]anthracene, benzo[b]fluoranthene, chrysene, benzo[k]fluoranthene, indeno[1,2,3-c,d]pyrene and benzo[j]fluoranthene were the most abundant PAHs found in the two air monitoring campaigns. Among the identified oxy-PAH the benzanthrone (7H-benz[d,e]anthracen-7-one) had the highest concentration and the evaluation of lifetime cancer risk showed an increase of 12 to 37 cases of cancer for every 10,000 exposed people. Chemical analysis of roasted cashew nuts identified the PAHs: phenanthrene, benzo[g,h,i]perylene, pyrene and benzo[a]pyrene, besides the 3-pentadecilfenol allergen (urushiol analogue) as prevalent. Occupational exposure to PAHs was confirmed by the increase of urinary 1-hydroxypyrene levels and genotoxic effects were evidenced by the increase on micronuclei and nuclear bud frequency in exfoliated buccal mucosa cells among the exposed workers. Other biomarkers of effects such as karyorrhexis, pyknotic, karyolytic, condensed chromatin and binucleated cells also have their frequencies increased when compared to an unexposed control group. The investigation of the molecular mechanisms associated with the PM organic extract showed cytotoxicity in human lung cell lines (A549) at concentrations ≥ 4 nM BaPeq. Using non-cytotoxic doses the extract was able to activate proteins involved in the DNA damage response pathway (Chk1 and p53). Moreover, the specific contribution of the four most representative PAHs in the cashew nut roasting sample showed that benzo[a]pyrene was the most efficient to activate Chk1 and p53. Finally, the organic extract was able to increase persistently the mRNA expression involved in the PAHs metabolism (CYP1A1 and CYP1B1), inflammatory response (IL-8 and TNF-α) and cell cycle arrest (CDKN1A) for DNA repair (DDB2). The high PM concentrations and its biological effects associated warn of the serious harmful effects of artisanal cashew nut roasting and urgent actions should be taken to the sustainable development of this activity.

Avaliação das atividades farmacológicas de fucoidans obtidos do extrato bruto de fucoidan comercial de Fucus vesiculosus

Fucoidan is a term used to define heteropolysaccharides that are composed of less than 90% L-fucose. The exception to this rule is the homofucoidan obtained from the seaweed Fucus vesiculosus. This fucoidan can be purchased from SIGMA Co. and have been used in various research for evaluation of their pharmacological activities. However, it is not a pure molecule. In fact, it is a mix of several fucoidan molecules. In this work, were obtained, from acetone precipitation, and biochemically characterized, four fucoidan molecules from SIGMA-ALDRICH Co. fucoidan to evaluate their anticoagulant, antioxidant, antiadipogenic, immunomodulatory and antiurolithiatic activities. In anticoagulant activity, evaluated by aPTT assay, fucoidans F0.9, F1.1 and F2.0 increased eightfold the coagulation time, compared to the control, when a mass of 10 μg was used. To PT test, only fucoidan F0.9 was capable of increase the coagulation time, compared to control. In the total antioxidant capacity assay (TAC), the fucoidan F2.0 showed 400 ascorbic acid equivalents, while fucoidan F0.5, the lest effective, 38 equivalents. In respect to the effect on pre-adipocyte cell lines (3T3-L1) adipogenesis, was observed that fucoidan F1.1 and F2.0 reduced the adipogenesis and this effect was associated to the reduction in the expression of regulatoy proteins C/EBPα, C/EBPβ and PPARγ. On the other hand, fucoidans F0.5 and F0.9 induced increased expression of these regulatory proteins. Furthermore, fucoidan F2.0 induced hydrolysis of triglycerides present in the interior of adipocytes. The immunomodulatory effect was evaluated and observed that the presence of fucoidans F0.5 , F1.1 and F2.0 significantly reduced the production of nitric oxide by activated macrophages with LPS specially fucoidan F2.0 that in 100 μg/mL, reduced about 55% the effect caused by LPS. Relative to the effect upon the formation of calcium oxalate crystals, fucoidan F0.5 was more effective in reduce the aggregation of the crystals and this effect it was not significantly different regarding the effect caused by the crude. Besides, fucoidan F0.5 only promoted the formation of COD type crystals, while fucoidans F1.1 and F2.0 did not influence the formation of crystals compared with the control. The results described in this study indicate that the commercial crude fucoidan of Fucus vesiculosus it’s a mix of several fucoidan which, in turn, have different chemical compositions besides having different pharmacological activities. The use of these fucoidans it´s indicated according the pharmacological activity to be evaluated.

Avaliação das atividades farmacológicas de fucoidans obtidos do extrato bruto de fucoidan comercial de Fucus vesiculosus

Fucoidan is a term used to define heteropolysaccharides that are composed of less than 90% L-fucose. The exception to this rule is the homofucoidan obtained from the seaweed Fucus vesiculosus. This fucoidan can be purchased from SIGMA Co. and have been used in various research for evaluation of their pharmacological activities. However, it is not a pure molecule. In fact, it is a mix of several fucoidan molecules. In this work, were obtained, from acetone precipitation, and biochemically characterized, four fucoidan molecules from SIGMA-ALDRICH Co. fucoidan to evaluate their anticoagulant, antioxidant, antiadipogenic, immunomodulatory and antiurolithiatic activities. In anticoagulant activity, evaluated by aPTT assay, fucoidans F0.9, F1.1 and F2.0 increased eightfold the coagulation time, compared to the control, when a mass of 10 μg was used. To PT test, only fucoidan F0.9 was capable of increase the coagulation time, compared to control. In the total antioxidant capacity assay (TAC), the fucoidan F2.0 showed 400 ascorbic acid equivalents, while fucoidan F0.5, the lest effective, 38 equivalents. In respect to the effect on pre-adipocyte cell lines (3T3-L1) adipogenesis, was observed that fucoidan F1.1 and F2.0 reduced the adipogenesis and this effect was associated to the reduction in the expression of regulatoy proteins C/EBPα, C/EBPβ and PPARγ. On the other hand, fucoidans F0.5 and F0.9 induced increased expression of these regulatory proteins. Furthermore, fucoidan F2.0 induced hydrolysis of triglycerides present in the interior of adipocytes. The immunomodulatory effect was evaluated and observed that the presence of fucoidans F0.5 , F1.1 and F2.0 significantly reduced the production of nitric oxide by activated macrophages with LPS specially fucoidan F2.0 that in 100 μg/mL, reduced about 55% the effect caused by LPS. Relative to the effect upon the formation of calcium oxalate crystals, fucoidan F0.5 was more effective in reduce the aggregation of the crystals and this effect it was not significantly different regarding the effect caused by the crude. Besides, fucoidan F0.5 only promoted the formation of COD type crystals, while fucoidans F1.1 and F2.0 did not influence the formation of crystals compared with the control. The results described in this study indicate that the commercial crude fucoidan of Fucus vesiculosus it’s a mix of several fucoidan which, in turn, have different chemical compositions besides having different pharmacological activities. The use of these fucoidans it´s indicated according the pharmacological activity to be evaluated.

Padrões de diversidade α (alfa) e β (beta) zooplanctônica em lagos tropicais: a importância da estrutura do habitat e da identidade das espécies

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Padrões de diversidade α (alfa) e β (beta) zooplanctônica em lagos tropicais: a importância da estrutura do habitat e da identidade das espécies

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Aprendizagem espaço-temporal e efeitos das condições luminosas no aprendizado do peixe paulistinha

Para processar a informação ambiental e perceber o tempo, os indivíduos utilizam-se de pistas ambientais, como luz e temperatura, que servem como guias para o relógio interno. O mecanismo temporizador endógeno é chamado relógio circadiano, o qual comanda uma grande variedade de ritmos diários bioquímicos, fisiológicos e comportamentais presentes nos organismos. Com isso, os animais podem antecipar eventos espaço-temporalmente distribuídos e usar essa informação para organizar as atividades diárias, o que é uma vantagem adaptativa para os indivíduos, já que muitos fatores ambientais apresentam variação circadiana. Aprendizagem espaço-temporal (do inglês: "time-place learning’’-TPL) é a habilidade de associar lugares com importantes eventos biológicos em diferentes horas do dia. Em nosso estudo utilizamos como modelo o peixe paulistinha (Danio rerio), conhecido por ser altamente social, para testar aprendizagem espaço-temporal baseada em reforço social. Além disso, objetivamos averiguar os efeitos das condições de claro constante e escuro constante na aprendizagem espaço-temporal, e se nessas condições, a atividade do peixe paulistinha é alterada. Para isso, testamos três diferentes condições (n=10): grupo claro-escuro (CE), grupo claro constante (CC) e grupo escuro constante (EE) durante 30 dias da seguinte maneira: diariamente, um grupo de 5 peixes paulistinha foi introduzido em um recipiente localizado no compartimento da manhã (um dos lados do aquário), às 8:00h e retirado às 9:00h, e em outro recipiente do compartimento da tarde (lado oposto do aquário), às 17:00h e removido às 18:00h, servindo como estímulo para que o peixe experimental ocupasse o compartimento onde o grupo fosse colocado. O comportamento foi filmado nos dois horários, 15 minutos antes e durante os 60 minutos de exposição ao estímulo, no 15º e no 30ª dia, porém neste último, os peixes foram filmados sem a presença do estímulo a fim de averiguarmos a aprendizagem espaço-temporal. Por fim, para saber a influência das três condições luminosas na atividade dos peixes, filmamos os últimos 6 dias de teste, para registrar o padrão de atividade. Nossos resultados mostraram que em ciclo claro-escuro (CE) o peixe paulistinha apresenta TPL, bem como é capaz de antecipar a hora e local do estímulo (grupo de coespecíficos), enfatizando a importância do estímulo social para a aprendizagem. Em condições de claro constante e escuro constante, o peixe paulistinha não apresentou aprendizagem espaço-temporal. Ademais, após 30 dias em condições luminosas constantes (claro constante e escuro constante), o peixe paulistinha mantém ritmo circadiano, porém em claro constante sua atividade é aumentada e seu ritmo atividade-repouso é alterado, através de um padrão de atividade distribuída homogeneamente ao longo das 24h, ao invés de concentrada na subjetiva fase clara, como nos grupos de ciclo claro-escuro e escuro constante, os quais conservam o padrão de atividade diurno da espécie.

Reserva extrativista Acaú-Goiana: tragédia comum ou decisão coletiva?

In recent years we have observed, in Brazil, the expansion of democratic spaces, providing the use of participatory management strategies in common-pool areas. However, the existence of a co-management model does not guarantee its practice, neither that it will prevent the depletion of common features characterizing the tragedy proposed by Hardin. In this work we analysed the management of Acaú-Goiana RESEX which is located in the cities of Acaú (PB) and Goiana (PE), eight years after its legal creation. We evaluated how much the users of RESEX possess information (even if non formalized) regarding the common use of area and whether they exhibit collectivist values. We used as an interpretative tool the facilitators principles of common resource management (PGRC) identified by Elinor Ostrom and the questionnaire of human values proposed by Schwartz. The human values questionnaire was applied to 240 individuals, half beneficiary and the other half non-beneficiary, only the beneficiaries were submitted to the questionnaire of PGRC. Interviews were conducted in the period of May to September 2014. We tested three hypotheses: 1) The degree of dependence from RESEX resources will play an important role on indirect knowledge of the PGRC; 2) the inclusion of individuals in a communal area (RESEX) increases collectivists values; 3) higher collectivist value rates increases knowledge of PGRC. To this end, we defined levels of socio-economic dependence of RESEX resources, knowledge of PGRC and individual values. GLM statistic analysis of mean comparison and correlation were employed. Our results showed that the knowledge on six of the seven items analyzed in the basic principles (PGRC) is still low. The extended land area and the high number of users may be exerting a detrimental effect on the development of a co-management. Contrary to expected, it was not the dependency who influenced knowledge on the PGRC, but the time spent in contact with the RESEX. This indicates that direct contact with the environment, not the dependence of it, that raises awareness about PGRC. According to our hypothesis, individuals with collectivist values showed greater knowledge of PGRC and reduced hours of work within the RESEX, indicating a greater tendency of individuals refrain their use of the common resource. Individualistic values correlated with less knowledge of a PGRC. Among the beneficiaries, individuals with higher individualistic values had higher monthly income, while among non-beneficiaries there was no such correlation, demonstrating the economic advantages of individualism (free-riding) in situations of non-private use of resources. Our data emphasize the importance of guiding the main actors in the development of a co-participatory management in the direction of the basic principles, and to develop collectivist values among users of a common good can raise awareness of these principles.

Estratégias tróficas do peixe traíra, Hoplias malabaricus e do peixe cascudo, Hypostomus pusarum do açude Marechal Dutra, Rio Grande do Norte, Brasil

The fish, Hoplias malabaricus (Osteichthyes: Erythrinidae) and armored catfish, Hypostomus pusarum (Loricariidae) are of freshwater origin from the neotropical region, and are considered ecologically and economically of important. This work investigated the trophic strategies, the morphology and histology of the digestive tract of these fish captured from the Marechal Dutra reservoir, Acari, the semiarid region of Rio Grande do Norte, Brazil. A total of 133 individuals of H. malabaricus and 118 specimens of H. pusarum were analyzed. The two study species occupy different levels in the food chain and spatial distribution in the water column of the reservoir. The results of this study are presented in the form of four scientific papers. The first article describes the morphology and histology of the digestive tract and the feeding habits of H. malabaricus (Bloch, 1794). This fish has a short intestine, with an intestinal coefficient of 0.72 ± 0.09. The dietary importance index indicates that H. malabaricus feeds preferentially on animal matter, especially on fish (72.8%) and prawns (27.2%). The histology of its digestive tract confirms the carnivorous feeding habit. The second article discusses about the pioneering work on the feeding strategy and the characterization of anatomy and histology of the digestive tract of H. pusarum. The intestine of this fish is long, with an intestinal coefficient of 10.8±0.7. The dietary importance index indicates that H. pusarum feeds preferentially on organic matter in decomposition (88.7%) and on filamentous microalgae and diatoms (11.3%). The third article compares the morphological aspects of the digestive tract of H. malabaricus and H. pusarum, in relation to their food habits. The arrangement of the digestive organs in both species is directly related to the shape of the peritoneal cavity and the form of the body. The short intestine of H. malabaricus and the long intestine of H. pusarum are associated with their feeding habits. The morphology of the digestive tracts of H. malabaricus and H. pusarum confirm their food habits, carnivorous and detritivorous / herbivorous, respectively. The fourth article discusses the food and reproductive aspects (length and weight, length-weight relationship, type of growth and sex ratio) of H. pusarum. This species has a negatively allometric growth, with the predominance of females in the sampled population. H. malabaricus inhabits the pelagic environment and is a carnivore, while H. pusarum, lives in the benthic environment and is characterized as a detritivore/herbivore. Each species studied shows a very different diet, without trophic competition between them. The morphological and anatomical structures of the digestive tract reflect their feeding strategy.