The spatial heterogeneity and seasonal dynamics of the floodplain of the Amazon River support its high fish diversity and productivity. This study investigated relationships between hydrological variations and habitat types with the taxonomic and functional composition and structure of lowland floodplain fish assemblages. Fishes were sampled in areas of 440 habitats distributed among lakes, channels, forests and herbaceous during periods of low, rising, high, and falling-water. The river level quota, local environmental variables and landscape characteristics were also collected to analyze their relationships with the assemblage structure. A total of 16.053 individuals were collected from 194 species, 118 genera, 34 families and nine species. Redundancy analyzes indicated that the taxonomic and functional composition and structure of the fish assemblages were associated with water levels, as well as with local environmental, landscape and spatial variables. Piscivores, planktivores and omnivores as well as species with periodic and intermediate life history. were more strongly associated with high water levels. During low water levels, herbivores, invertivores and detritivores as well as species of large body size with equilibrium life history were the most representative groups. NMDS and dissimilarity analyzes showed differences between the trophic compositions of the habitats during the high water period, with lakes and channals being more similar to each other and dissimilar to forest and herbaceous habitats. Mean values of biomass in terms of CPUE of invertivoress, omnivores and piscivores were higher in the forest, while of detritivores and plankivores in lakes, and herbivores in herbaceous. These results suggest that changes in the natural hydrological regime and the degradation of habitats are likely to negatively impact the abundance and biomass levels and the taxonomic and functional structure of the tropical lowland fish fauna. Therefore, to conserve the productivity and taxonomic and functional diversity of fishes in the Amazonian floodplain it is necessary to conserve natural hydrological regimes as well as mosaics of habitat types within the ecosystem.

The increase in the number of fish farms in the national territory associated to the intensification of production, there have been outbreaks and high fish mortalities due to the diseases. One of the main obstacles is the occurrence of parasitic infestations, followed or not by the presence of opportunistic pathogens. Among these opportunistic pathogens are crustaceans, periodic ectoparasites of marine and sweet fish. Among the crustaceans, there is the subclass Branchiura, popularly called "fish lice" or Argulídeos, which compromises sanity in aquaculture, so its control is fundamental. However, the use of natural products (phytotherapics) has been gaining prominence in animal health, mainly because they are efficient bioactive substances in parasitic control. One of these plants with potential use in aquaculture is the holy grass (Cymbopogon citratus), the essential oil extracted from this plant is efficient in the control of bovine ectoparasites. This thesis studied the effects of the essential oil of C. citratus in the control of ectoparasites of fish belonging to the family Argulidae (Dolops discoidalis and Argulus sp), through the LC50-24h test with dosages 20 μg/L, 40 μg/L; 60 μg/L, 80 μg/L, 100 μg/L, 120 μg/L, 140 μg/L and 160 μg/L. The maximum mortality for the representatives of Argulus sp started from the concentration of 100 μg/L, while the maximum mortality of Dolops discoidalis started in the treatment of 80 μg/L. The Lethal Concentration (LC50-24h) for adult Argulus sp was 76,3μg / L and adult Dolops discoidalis was 59,3μg / L. It was observed that all mortality in the test (LC50-24h) occurred in the first hour. The essential oil of C. citratus was also tested (LC50-24h) in the ovipositions of argulids, in both the maximum mortality (100%) of the ovipositions started from the treatments of 140μg / L and 160μg / L. The Lethal Concentration (LC50-24h) for the ovipositions of Argulus sp and Dolops discoidalis were 99,7 μg / L and 99,3 μg / L, respectively. The parasite phase was important for the definition of the control concentration. In addition, studies are required to evaluate the effect on infected fish for the indication of this oil in aquaculture, since in this work, low concentrations of C. citratus O.E. CL were determined in the control of adult Argulids.

This study deals with fisheries agreements as a participatory management tool in the Aritapera region (Pará / Brazil), making an analysis of its effectiveness. The dynamics of fishing in these communities and their social actors are described in summary. These agreements arose from the pressure exerted on the communal lakes of floodplain, from the decade of the 70, where the riverside communities began to restrict the access to these environments. One of the main legal instruments for fisheries control used as a participatory management tool, as well as promising in increasing and maintaining fish stocks. It is necessary to evaluate this management tool as a support to obtain results on the efficiency of these agreements. The agreements of the Aritapera region in the first moment were regularized by means of ordinances and later recognized by means of Normative Instruction of Ibama n ° 11, of October 14, 2004. In the second moment, from the need of land regularization, INCRA in partnership with IPAM, created the Aritapera Agro-Extractive Settlement Project (PAE), making a total of 14 communities that had their fishing agreements introduced into the Plan of Use of the PAE by inserting them into a fishing chapter. The selected communities for this research were: Ilha de São Miguel, Água Preta, Boca de cima and Cabeça d'ounca. The main source of income of these communities is fishing that occurs all year long and agriculture during the drought in the Amazon, the main environments used for fishing are community lakes, adapting their techniques and fishing gear according to rise and fall of the waters the fishing equipment, with the exception of the hammer that has its use cited all year. Among the communities studied, the oldest fishing agreements are from the Ilha de São Miguel and Água Preta communities dating back to the 1980s and 1990s, respectively, Boca de Cima and Cabeça D'onça communities had no formalized agreements and only came to have after the Utilization Plan (PU). Fishing conflicts were observed in all the communities studied, with the highest citation in the Agua Preta community. The greatest difficulty found in the implementation of the agreements is due to the lack of respect for the rules of the current agreement and due to the low state performance in the absence of inspections in these communities. The objective of this study was to evaluate the effectiveness of management measures for fisheries agreements in the Aritapera region, Santarém-PA.

Diatoms (Ochrophyta, Bacillariophyceae) are microalgae that occur in all aquatic environments, accounting for most of the primary production in the oceans and freshwaters, constituting an expressive portion of the periphyton in these environments. Periphytic diatoms have been used as indicators and monitors of water quality in several countries. In Brazil, few studies with this approach were carried out, restricted to the south of the country, and nonexistent in Amazonian rivers. The Urumari is an urban igarapé located in the municipality of Santarém that it has suffered the consequences of the population growth in its surroundings. In order to identify diatom species with potential use as indicators of water quality, samples were taken from September 2018 to March 2019, in five sampling stations, comprising upper, middle and lower portions of Urumari. Artificial acrylic samplers were used for colonization of the periphyton, which were submerged for 30 days. In all, 220 taxa were registered, belonging to 17 families and 35 genera. Of these, 26 occurred with abundance above 5% in the samples. The most representative genera were Eunotia (24%), Pinnularia (19%), Nitzschia (7%) and Navicula (6%). The most downstream station (E5) had the highest dominance values. The Shannon-Wiener index ranged from 2.5 to 3.5. Eunotia parasiolli, Frustulia saxonica and Nitzschia palea occurred in 100% of the samples. The principal components analysis indicated a spatial gradient of organic contamination, from upstream to downstream, characterized by decreased dissolved oxygen concentration and increased BOD, pH and nitrogen and phosphorus concentrations. The results of the canonical correspondence analysis, TWINSPAN and IndVal indicated that there is a significant spatial variation in the composition and structure of the diatom assemblies, with substitution of some species for others with greater tolerance to organic pollution, along the course of the igarapé do Urumari. Thus, it was possible to select species with a potential indicator value and to relate them to four scenarios or groups of water quality: group I: Eunotia femoriformis, E. parasiolli, E. conectival 13; group II: Brachysira procera, Eolimna minima, Placoneis merinensis, Pinnularia brauniana ,; group III: Achnanthidium exiguum, Frustulia cf. crassinervia, Pinnularia microstauron, Sellaphora pupula; group IV: Encyonopsis frequentiformis, Frustulia quadrisinuata, Navicula cryptotenella, N. cryptocephala, Nitzschia palea, Stenopterobia planctonica. The results indicated that diatom species are highly sensitive to physical and chemical changes in water even when the amplitude of these variations is not very large and confirm that these organisms can be a valuable tool for the diagnosis and monitoring of watercourses that suffer impacts of human activities. Although, the Urumari igarapé has not already yet its original characteristics, it still presents moderate impacts in its way when compared to other urban rivers of Brazil, and possibly can be recovered in relatively small time, if the necessary actions are carried out.

Natural products are being tested as anesthetics in fish, in order to mitigate the effects of stress caused by management techniques applied in aquaculture. The objective of this work was to evaluate the use of Myrcia sylvatica hydrolate (MSH) as anesthetic in tambaqui juveniles (Colossoma macropomum), well as assess the lethal concentration (LC50-96h). The concentrations of MSH used to anesthesia experiments, were 15, 20, 25, 30 and 35% (15 fish per treatment). The lethal concentration tested were used 5, 7.5, 10, 12.5 and 15% of MSH concentrations. The physical-chemical variables (temperature, pH, electric conductivity and dissolved oxygen), flow of Na +, K +, Cl-, ammonia and alkalinity of the solutions were evaluated before and after test. The gill mucous cell density (MCD) was determined after 96 hours of exposure to HMS. The 30% concentration of MSH had the best anesthetic induction and recovery times and was indicated for fast handling (about 3min). The acute toxicity test estimated CL50 in 11,19% of MSH. Juveniles of tambaquis exposed to MSH for 96 hours presented high excretion of ammonia and efflux of ions, increasesed with concentration of hydrolate increases. The MCD decresed with increase the concentration of MSH. Thus, the concentration tested of HMS are not indicated for prolonged managements was suggested, because induced osmoregulatory stress.

This work aimed to analyze the traditional knowledge of fishermen about reproduction, feeding, habitat and behavior of the main fish species, as well as to describe socioeconomic aspects, fishing characteristics and the current situation of fishery resources, and to analyze the environmental perception of fishermen in identification of conflicts / problems in the region in order to gather subsidies to contribute to the management policies of the fishing resources of the region and that may be useful in the elaboration of the APA-Maicá management plan, helping to propose important strategies for the management, conservation and sustainability of the species and maintenance of the local fishing activity. Data were collected between march and december 2017 through semi-structured forms applied directly to fishermen associated with Fishermen's Colony and Fishermen Z-20 or who live in the communities and / or neighborhoods that are inserted in the proposed area for the implementation of APA-Maicá or are linked to one of the four existing Core Units in the area. For the ethno-ecological analysis, we interviewed 88 fishermen who had ten or more years of fishing experience in the region. Fishermen's knowledge was consistent, detailed and consistent with the scientific literature. The fishermen indicated the size of the first sexual maturity of the fish, information that added to the biology and reproduction of the species is extremely important in the formulation of measures of adequate fishing management to the region. It was also reported a diversity of items used in fish feed, in addition to the numerous habitats used by the species, which suggests the great dependence of the fish for this environment, either as a place of food, shelter or reproduction. A total of 96 fishermen were interviewed to characterize fishing activity, socioeconomic profile and environmental perception. The fishing activity in the Maicá region is presented as small-scale and artisanal, with the use of relatively simple equipment, with emphasis on the gillnet, preferably in motorized canoes and oars for the capture of 32 categories of fish. The main fishing site is the lake and its surroundings, used in all the seasonal periods, with predominance in the moments of full and ebb of the local hydrological cycle, proving itself as a relevant ecosystem and an important means of subsistence for these communities and / or neighborhoods that develop in their surroundings, being one of the main sources of occupation, food, subsistence and income. Fishermen's perception shows that they understand and have a broad environmental vision with awareness of the problems affecting the environment in which they live, such as the marked decrease in fish caused by actions of anthropic origin, among which of fishery that involves different actors), overfishing, deforestation and lack of inspection, as well as the socio-environmental conflicts existing in the region, always showing concern for the future of fishing in the region, which led to the suggestion of mitigating measures, such as APA-Maicá regulations. These results reinforce the importance of the incorporation of the traditional knowledge of the fishermen in the management plans, as well as the use of the relevant information of the socioeconomic components and of the fishing activity that must be used to measure the response of the fishing industry to the proposed management system.

The use of natual products in aquaculture has been intensifying, appearing as an alternative for improvement in production as food supplements, insecticides, anesthetics and sedatives. The objective of this work was to evaluate the use of the Myrcia sylvativa hydrolate (HMS) under simulated conditions of transport of tambaqui (Colossoma macropomum) juveniles at different densities. Tambaqui juveniles (3 to 5 cm) were placed in plastic bags. For a 17 h simulated transport at loading densities of 30, 60 and 90 juveniles/L in three concentrations of HMS (2.5, 5 and 7.5%) and control water (CA). Survival was verified immediately after transport and after 24h (characterized as post-transport). The physical and chemical parameters of the water were evaluated before and after the transport (temperature, pH, alkalinity, hardness, dissolved oxygen, electrical conductivity and total dissolved solids), as well as the net flow of Na+, K+, Cl- ions and excretion of ammonia. In addition, the density of gill mucous cells was observed after transport. There was no significant difference in survival between treatments and densities. Temperature, hardness, total and non - ionized ammonia showed no significant difference between treatments and density. However, the pH presented a difference even at the initial values, reducing as a function of the increase in HMS concentration. The dissolved oxygen was significantly lower when the initial and final values were compared. Alkalinity and total dissolved solids increased significantly as a function of density. The conductivity and ionic flow (Na+, K+, Cl- . were lower in the treatment with 5% HMS mainly at higher density. The number of mucosal cells neutral and acidic gills was lower in 5% HMS at the higher charge density. The use of HMS at 5% concentration may be recommended for the transport of long-lived tambaqui juveniles 17h. Although it did not differ significantly from the control group in the percentage of survival, however, it presented low fluctuations in pH values at all densities and at the density of 90 fish / L it reduced the efflux of Na+ and K+ and Cl- ions, and did not stimulated the production of neutral and acidic gill mucosal cells, which proved to be a potential stress reducer and effective at higher densities. This work is the first study with the use of Myrcia sylvativa hydrolate with application in aquaculture management.

The Municipality of Alenquer, located in the mesoregion of the Lower Amazon, has a fishing activity, so far little studied, probably because it is not part of the axis of the great fishing ports of the Amazon. This knowledge gap makes it difficult to understand the dynamics of fishing in the region, as well as its contribution to the Amazon fishery scenario. This study aimed to evaluate the dynamics of fishing and its spatial effects in the municipality of Alenquer. The information was collected through a participatory fishery monitoring between the years 2010 to 2016. The data were stored in a database with continuous fishing information. Data spatialization was performed using free software QGIS, version 2.14, for buffers, interpolation and vectorization. Monitoring the dynamics of fishing recorded 52,853 fisheries, with a total catch of 1,203,681 kg of fish and a gross financial volume of R $ 3,610,102.20. The fishermen used canoes, bajaras and boats as fishing vessels. For fishing, a variety of equipment was used, especially for gillnets. The catch was composed of 38 groups of fish. The groups of fish as surubim (Pseudoplatystoma punctifer, P. tigrinum); tucunaré (Cichla monoculus, Cichla sp ); curimatá (Prochilodus nigricans); pescada (Plagioscion squamosissimus; P. sp); aracu (Schizodon fasciatus, S. vittatus, Leporinus spp, Rhytiodus argenteofuscus, Laemolita taeniata); pirarara (Phractocephalus hemioliopterus); aruanã (Osteoglosum bicirrhosum); acara-açú (Astronotus crassipinnis; A. ocellatus) e pacu (Metynnis spp, Mylossoma duriventre, M. aureum)accounted for 77% of the total catch. The fisheries were mainly made in lakes (89%), with a record of 863,093 hours of fishing, presenting a better CPUE (1,23) and catch (1,058,969 kg) than paranás environments and rivers. Higher values of catch, CPUE and income occurred during the water ebb period. The lakes are extremely important environments for commercial fishing, all year round, with emphasis on the ebb period, whose catches are concentrated in sedentary species and small and large migratory species. The spatialization of the fishing dynamics allowed to verify that the fishermen operate in a radius of 44 km, exploring 106 fishing environments. The catch varied according to the magnitude of fishing effort practiced by the fishermen in the fishing environments. The environments were not fishing points with higher fishing frequencies in the respective years of prominence in the catch, indicating that the fishermen exploit these places in moments of fish concentration. There is territorial overlapping of the base nuclei in the use of fishing environments. With this, the present study proposed the definition of territorial units of fishery management of lakes, in an integrated, participatory and adaptive perception.

Mercury is a chemical element that presents high toxicity to living organisms. It bioaccumulates according to the weight and age of the individual, if it biomagnifies along the different trophic levels of the food chain, besides being transferred directly to the organism through the water. The present study aimed to investigate the dynamics of total mercury (HgT) in the UHE CuruáUna. Investigating the concentrations of HgT in muscular tissue of fish in different stretches in the UHE Curuá-Una; to verify the species that had concentrations within the limits allowed by WHO and ANVISA legislation; if the limnological variables influenced the concentrations of HgT and the bioconcentration of HgT in fish and periphyton in the different stretches in the UHE Curuá Una. The samples were collected in three different stretches (reservoir, transition and downstream) at UHE Curuá-Una, located in the western part of the state of Pará. All biological samples (water, fish and periphyton) were analyzed using the Atomic Fluorescence Cold Vapor (CVAFS). A total of 298 specimens were distributed in four species: Auchenipterus nuchalis (Spix & Agassiz, 1829) (n=58), Curimata knerii (Steindachnner, 1876) (n=62) and Hemiodus unimaculatus and Serrasalmus rhombeus (Linnaeus, 1766) (n=105). Only Hemiodus unimaculatus and Serrasalmus rhombeus showed significant differences between the different stretches, with H. unimaculatus presenting higher concentrations in the reservoir (150.24±96.26 ng.g1 ) and lower ones (78.40 ± 47.46 ng.g-1 ), and in S. rhombeus, the highest concentrations at the transition (427.45±245.51 ng.g-1 ) were observed, and the lower ones at the downstream (181.73 ± 76.18 ng.g-1 ). In the case of HgT concentrations, the upstream stretch (148.53±132.99 ng.g-1 ) was significantly different (H=23.46; p=0.0000) of the transition passages (292.47± 240.35 ng.g-1 ) and reservoir (249.52±232.36 ng.g-1 ). The concentrations of HgT between the trophic levels showed significant differences (H=136.30; p=0.000) between the concentrations of detritus feeding organisms (94.36±74.20 ng.g-1 ) and those of habit (324.97±245.61 ng.g-1 ) and insectivorous (338.26±203.04 ng.g-1 ), the latter two with higher concentrations. There was a significant difference in bioconcentration between trophic levels (H=81.93; p=0.00), demonstrating that the species that were at the lower trophic level of the trophic chain are bioconcentrating less (1.40±027 ng.g-1 ) than the top-chain species (2.01±0.32 ng.g-1 ). However, no significant differences were observed in the bioconcentration in the periphyton between the different stretches, but it was noteworthy to observe that the largest bioconcentration factor was transition (1.87 ng.g-1 ), followed by downstream (1.73 ng.g -1 ) and reservoir (1.62 ng.g-1 ) of the dam.

O presente trabalho tem como objetivo identificar a composição taxonômica, verificar a abundância e caracterizar a distribuição temporal do ictioplâncton nas regiões de águas abertas do lago e a relação dos organismos com as variavéis ambientais, como forma de auxiliar na definição de melhores práticas de uso sustentável da biodiversidade que têm se mostrado cada vez mais importante no cenário atual. As coletas foram realizadas no período diurno e noturno no ano de 2015, em nove estações de amostragem, localizados no lago Maicá próximo à cidade de Santarém. Foram realizados arrastos horizontais na subsuperfície da coluna d'água, com rede de plâncton (300m). Foram capturados 2.525 ovos e 6.961 larvas de peixes, classificadas em 63 táxons e distribuídas em 10 ordens, 25 famílias, 41 gêneros e 53 espécies, a maioria das espécies são migradoras e de importância comercial. A ordem dos Characiformes (41,79%) e Clupeiformes (31,48%) foram mais abundantes, somando 73,27% do total de larvas capturadas. As maiores densidades de ovos e larvas foram capturadas no mês de janeiro e dezembro (5,92 ovos/10m3 e 54,46 larvas/10m³) correspondendo à época de reprodução da maioria das espécies de peixes explorados pela pesca na região. A composição de larvas diferiu ao longo dos meses (Pseudo F=0,94; p<0,01), indicando um gradiente de sazonalidade, com pico de larvas em diferentes meses mostrando que as espécies de peixes têm estratégia reprodutiva distintas. Dos táxons identificados as larvas de Mylossoma aureum e M. albiscopum, Plagioscion squamosissimus e Engraulidae, foram as mais abundantes. Em relação ao ciclo diário diferenças significativas foram detectadas, com maiores densidades de ovos (35,29 ovos/10m³) e larvas (76,62 larvas/10m³) registrada e no período noturno. Dos táxons identificados, apenas 1 taxa foi registrado de dia, 34 somente pela noite e 27 táxons ocorreram tanto de dia quanto de noite. Quanto aos estágios de desenvolvimento 98,65% dos ovos encontravam-se em clivagem inicial e 70,78% das larvas no estágio de pré-flexão. A variação do índice pluviométrico e oxigênio dissolvido, foram as variáveis ambientais que melhor explicam o padrão de distribuição temporal do ictioplâncton. Os resultados confirmam que várias espécies de peixes, têm utilizado o lago Maíca como área de desova e criadouro natural, ressaltando assim a sua importância para a reprodução, consequentemente, para a manutenção das espécies de peixes no trecho baixo do Rio Amazonas, evidenciando a necessidade de sua preservação.

The Sono River is a clear-water affluent of the right bank of the upper-middle Tocantins river, formed by the rivers Novo and Soninho. This work aimed to investigate the biotic or abiotic factors that may influence the structure of fish assemblages in the Sono River drainage in three different periods of the hydrological cycle. Fish sampling and
environmental variables were performed at nine sampling points, in the months of January 2016 (flood period), April 2016 (ebb period) and June 2016 (drought period), using holding nets, spines, traps, sieves, traps and trawl nets and electrofishing. A total of 1.838 individuals belonging to 111 species, 78 genera, 25 families and seven orders were collected. The most abundant species were Rhinopetitia sp., Bryconops aff. melanurus and  Geophagus proximus. An analysis of variance revealed significant differences in the richness recorded during the flood period of those recorded in the ebb and dry periods. The values of abundance and equitability obtained in the drought period were different significantly from those recorded during the flood and ebb period, and a significant difference was observed in the diversity between flood and ebb periods. The temporal difference was significant in the fish species composition between the periods for qualitative and quantitative data. Richness was positively correlated with temperature. Equitability was positively correlated with pH and dissolved oxygen. Richness, abundance and diversity were negatively correlated with turbidity and positively correlated with equitability. The dissolved oxygen had a significant influence on the abundance of the species. In addition to this variable, the distance of the mouth and the total dissolved solids were the variables that showed a strong correlation with the abundance of the species. Was verified a significant difference of the trophic guilds in the three sampled periods. The knowledge of environmental factors, such as dissolved oxygen, turbidity, temperature and pH influencing the structure of fish assemblages, reinforces the need to elaborate management measures that seek to ensure the integrity of the biological assemblages in the Sono River drainage.

The fish consumption around the world have grown in the last decades in order to supply the large demands,fish production increased and the pressure on resouces increased leading to a fall in inventories.In the Amazônia,the fishing carry out an important function on food security and economy of local populations,factors such as climatic variation and managemant order regulate the unloading in this region.Defeso is a managemant order more widely used in the fishing,but its effect but its effect is not clear about fish inventories.this work was analyzed time sequence of the unloading of species categories protected by defeso at the fishing fair,Santarém-PA with objective of understanding the behavior over time of the production and their connection with the climatc variation and defeso season.results indicate that the protected groups are among the major resoucers lunloading and show seasonal oscilation interanual of production in accordance with characteristcs environment.Notes that variation and fishing production conforms to the dynamics of flooding of aquatic enviroments.conforms to the biologyof the study groups.Even during the defeso it was possible observe protected species present in the unloading.in also note na increase during the defesos in wich the ban was suspended (2015-2016),as climatic variation,the el ninõ cause preciptation deficities and drought in the Amazon basin,result large eficience of fishing aparatus and increased production.The suspended of the defeso season combining with increased and the fishing pressure on protected fish groups.observad in the volume elevation of fish unloading.

Fish constitute the most specious group among the Craniata, comprising about half of
vertebrates known in the world. With regard to freshwater fishes, the greatest diversity is
found in the Neotropical region, which includes, among other regions, the Amazon basin,
which has a gigantic network of small streams, called regionally streams, responsible for much
of this biodiversity. The waters of these streams are relatively acidic, poor in mineral salts and
with low concentration of calcium and magnesium. These streams, especially of smaller order
and on land and / or headwaters, usually have their courses covered by the canopy making
their fauna dependent on the adjacent forest. The objective of this study was to know the
structure of the fish assemblages in streams of the streams National Forest in two periods of
the seasonal cycle, as well as to evaluate the effects of the El Nino climate phenomenon on the
fisiography and ichthyofauna of these streams. For the first objective, collections were made in
two distinct periods, the first in the dry season (from September to November 2015), and the
second in the rainy season (March to May 2016). The second objective was to analyze samples
of environmental and ichthyofauna variables from the drought of the year 2013 and from the
recent drought surveys of 2015. The fish were collected with trawls and sieves in 22 1st and
3rd order streams. During the dry season, 2,452 individuals distributed in 96 species were
collected. In the rainy season, 1,092 individuals were collected in 67 species. The 3,517
individuals are distributed in 105 species that compose in 27 families and six orders. The
greatest riches were in the families Characidae, Cichlidae and Loricariidae. The results showed
that there were no differences regarding composition in the different periods sampled. As for
wealth and abundance, there were significant differences. The scientific knowledge generated
through this study may guide future management actions in the conservation unit. Actions
that will subsidize from the adaptation of the zoning of the unit for the preservation of rare or
endemic species, to the economic management of species for aquarium or observation dive.

The heavy metals as mercury (Hg) is considered the most toxic and poses a great risk to the environment. In addition to its high toxicity, mercury contamination is widely discussed with respect to two important processes that it undergoes in contaminated organisms: bioaccumulation and bioconcentration. Fish are good indicators of Hg contamination and in reservoirs these have presented high levels of contamination, mainly carnivores. Fish collected downstream from the dams have demonstrated higher Hg levels than the amount. In the Amazon region, the main route of exposure to mercury is fish consumption, especially by riverine communities. The hydroelectric reservoirs of Curuá-Una, inaugurated in 1977, was the first dam built in the Central Amazon, which is our area of study. The objective of this work was to examine the concentrations of total mercury in fish muscle tissues at different collection points in the Curuá-Una Santarém/PA HPP. The fish samples were collected in September 2011, during the river ebbing period. Samples of the ichthyofauna occurred at nine collection points, seven upstream of the dam and nine downstream, on the Curuá-Una river. The water, sediment and fish samples were analyzed by Cold Vapor Atomic Fluorescence Spectrometry-CVAFS. To analyze the data was used Analysis of Variance-ANOVA, Pearson's Correlation and Linear Regression. A total of 283 individuals belonging to 15 species were analyzed. No species had an average concentration of HgTotal above that allowed by National Health Surveillance Agency-ANVISA and World Health Organization. However, in five species, some individuals had absolute individual concentrations that exceeded the limit tolerated for human consumption. A total of 283 individuals belonging to 15 species were analyzed. Auchenipterusnuchalis, an omnivorous / insectivorous food habit, was the species that presented the highest average concentration of HgTotal and also obtained the highest Bioconcentration Factor. The species Hemiodus unimaculatus, collected downstream of the reservoir showed a trend of higher concentration of HgTotal than collected upstream. There was no relationship between HgTotal levels in fish with HgTotal levels in water and sediment, nor with limnological variables. Catoprionmento, a detritus species, obtained the lowest mean concentration. Among the species studied, one presented bioaccumulation, Acestrorhynchuscf. Microlepis(piscivora).

The Cupari River is the main tributary of the right margin of the lower Tapajós River, which are planned deployments of 13 Small Hydroelectric Plants (SHP). This study aimed to investigate environmental factors that may influence the structure of fish assemblages in Cupari River and analyze the efficiency of two methods of fish sampling. Sampling of fish and environmental variables were realized in 11 sampling points in the months of December 2014 (low water) and May 2015 (high water), using gillnet and manual traction seine. Were collected 3.273 specimens, representing 144 species, distributed in 80 genus, 34 families and nine order. The most abundant species were Moenkhausia aff. ceros, Rhinopetitia potamorhachia and Knodus sp. 1. There was not statistically significant difference in species composition between sampling periods. The abundance was positively correlated to temperature. The richness and diversity were positively correlated with dissolved oxygen. The dominance was negatively correlated with dissolved oxygen. The distance of sampling points for the mouth of Cupari River and altitude did not affect significantly the values of the ecological descriptors. Three species were recognized as new and were recorded two endangered. There was significant difference in composition, richness and abundance of species caught by different methods. The results are of relevance for the conservation and allow the proposition of management measures for ichthyofaunistic resources in Cupari River

This study evaluated the structure of the phytoplankton community in Lago Grande de Curuai, PA, in a hydrological cycle. The samples were collected monthly during one year in three sampling sites at two depths (subsurface and bottom). The phytoplankton was quantified by Utermohl method and the biovolume was measured by specific geometrical forms. The lake is characterized by 'white waters' type and the thermal stratification was not observed. The phytoplankton community was represented by 122 taxa and 8 taxonomic classes: Cyanobacteria (28 taxa), Cryptophyceae (3), Dinophyceae (4), Crysophyceae (2), Bacillariophyceae (31) Euglenophyceae (5), Chlorophyceae (42) and Zygnemaphyceae (7). Significant differences were observed biovolume according to the hydrodynamics of the lake. Cyanobacteria were the most representative in the falling waters were potentially toxic species blooms were observed, as Dolichospermum circinale and Dolichospermum flos-aquae. The phytoplankton functional groups (FG) are represented by K, M, H1, S1, T, Lo, Y, X2, G, W1, W2, A, C, Q, MP and J and morphological and functional groups (GFBM), by III, IV V, VI and VII. The MBFG was the one best the hydrodynamics of the lake.

Zygnemaphyceae, better known as demydiae, is undoubtedly the best represented group of continental algae in terms of species numbers, varieties and taxonomic forms, besides being one of the most studied algae classes in Brazil. In Lago Verde (clear water flooding system) scientific articles of this nature are relatively scarce or nonexistent. This lake is located in the Alter do Chão Bathing Village, Santarém Municipality, Pará State, Amazon, Brazil. In this context, the present work had the objective of conducting a floristic survey of the desmidia genus: Cosmarium (Chapter I) and Staurastrum (Chapter II), describe morphologically, illustrate, analyze frequency of occurrence based on the methodology of Mateucci & Colma (1982) and report the geographic distribution of these genera in the State of Pará. Twenty-eight samples were collected from plankton net. (20 μm mesh) in the limnetic region in the periods of low water (November and December 2013) and high water (May and June 2014), in seven sampling stations and analyzed by Optical Microscopy. A total of 39 taxa were recorded, of which 23 Staurastrum and 16 Cosmarium taxa. Of these, six desmídias taxa are being added for the first time to the State of Pará ficoclower and are illustrated in the present study (C. contactum var. retusum e C. peseudopyramidatum var. rotumdatum, St. punctulatum var. punctulatum f. minor; St. pachyrhynchum var. pachyrychum f. pachyrychum; St. furcatum e furcatum e St. jurucuiense). In general, the occurrence of the species can be attributed to some characteristics of the environment, such as slightly acidic waters and reduced electrical conductivity, conditions cited in the literature as favorable to the development of media. Therefore, the studied genera were well represented in green lake, when compared to the richness registered with other regions of the Amazon and Brazil, demonstrating the relevance of the work developed for the taxonomy and the knowledge of gender diversity in the State of Pará. In addition to the detailed descriptions, it provided cellular measurements based on population variation and figures for all taxa. Additionally, it provides subsidies for future ecological and conservation studies of this Amazonian flood lake, considering the high level of tourism activity and urban expansion in the region without environmental planning.

The objective of this study was to evaluate the potential of the Lippia alba essential oil as an additive in the simulated transport of tambaqui (Colosoma macropomum) fingerlings, observing the survival and behavior of the chemical parameters of the water. The simulated transport was performed for 17h in closed system (plastic bags) and the concentrations of essential oil used were 5 and 20 μL.L-¹. Three control treatments were also evaluated: Pure water (Cagua); water + alcohol (CA + Al) and terramycin + salt (CT + salt). The stocking density used was 105 fish.L-1 or 117.6 g.L-1 and each treatment had 3 replicates each. The physico-chemical parameters of the water (pH, temperature, dissolved oxygen and conductivity) were measured with the aid of a multiparameter probe. Survival was calculated by counting the total number of live and dead individuals after 30 min of acclimatization in running water. Survival in all treatments was satisfactory, with the highest values found in treatments LA [20] and CT + salt (99.06% and 99.34%, respectively). The lowest survival was found in LA treatment [05] (90.14%). In relation to oxygen, CT + salt treatment presented the worst results (1.21 ± 0.63 mg.L-1). The treatments with essential oil obtained satisfactory results of dissolved oxygen, in LA [05] the value of 4.03 ± 0.31 mg.L-1 was obtained and in LA [20] 3.01 ± 0.44 mg.L-1. The pH values were within the comfort range for the species in all treatments. The use of L. alba essential oil at a concentration of 20 μL.L-¹ is effective in the transport of tambaqui fry, resulting in high survival rates and maintenance of dissolved oxygen levels.