Chemical Exposure Hazardous for Fish Hyphessobrycon eques through the Incorrect Release of Oil in Amazon Region

Incorrect discard of oil used by fishing ship in the brazilian north region has become a common activity. Despite the possible hazard to the aquatic organisms, still missing scientific data about their toxicity. Thus, this study aimed to evaluate the stress and lethality caused by lubricant oil (FSAOLU) on fish Hyphessobrycon eques. Therefore, it was used six different concentration diluted in water (0, 22, 24, 26, 28, 30 and 32% of oil) and three replaces during 96 hours. At the end or during the experiment (with dying fish), it was collected blood samples (cutting the caudal fin) to determine physiological changes. The FSAOLU showed mean lethal dose (LD50-96h) of 27.36%, classified as toxic causing alterations in glucose values from the 26%. The greater dilution of FSAOLU (32%) increased 115% in glucose values when compared to the control. Thus, lubricant oil when discarded in water, it present hazard to the aquatic organisms causing stress and mortality for fish being necessary adequate management to discard of this residue

Parasite Fauna of Lutjanus synagris Commercialized in the Fish Market from Bragança-PA, Brazil

Studies about the parasite fauna of marine fish highlights as an important problem for public health with zoonotic parasites or affecting the fish quality. Thus, this study evaluated the parasite fauna of Lutjanus synagris commercialized in the fish market from Bragança-PA. In laboratory, 58 fish were measured, weighted and conducted to parasitological analysis to determine parasitological indexes and relative dominance. Every parasite was fixed and identified until to the lowest taxonomic level. Through the parasitological analysis, it found Cymothoidae, Digenea, Cucullanus sp. and Procamallanus (Spirocamallanus) sp., with total prevalence 67.24%. Digenea showed the highest prevalence and mean intensity values. For nematode, Cucullanus sp. obtained the greater prevalence and relative dominance, while Procamallanus (Spirocamallanus) sp. showed the greater mean intensity and abundance. Cymothoidae showed the lowest prevalence and mean intensity values. As conclusion, the parasite fauna of L. synagris has been noted with low diversity, reporting the nematode occurrence Procamallanus (Spirocamallanus)

Suplementação com arginina na dieta de tilápia-do-nilo produzida em tanques-rede

The objective of this work was to evaluate the effect of dietary arginine concentrations on the health status of Nile tilapia (Oreochromis niloticus) cultivated in cages. The experiment was carried out in a completely randomized design with four treatments (2.3, 2.9, 3.5, and 4.1% arginine in dry matter) and three replicates, in 12 net cages of 8 m3, containing 4,000 sexually reverted tilapia (63±20 g, at 500 fish m-3). Fish productive performance and health were evaluated. Biochemical, hematological, and immunological parameters, as well as the morphological aspects of gills and liver, were evaluated. Arginine inclusion did not cause significant differences in fish growth performance. However, arginine supplementation at 3.5% concentration improved the biochemical parameters and leucocyte counts, consequently improving the immune system. The arginine concentration of 4.1% caused lipid degeneration, shown by the increase of alanine aminotransferase and the decrease of albumin, urea, lactate, and glucose. Arginine supplementation above 2.3% and below 3.5%, in the diets of tilapia reared in cages, improves fish immune system, without adverse morphological and physiological effects.O objetivo deste trabalho foi avaliar o efeito de concentrações de arginina dietética sobre a saúde da tilápia-do-nilo (Oreochromis niloticus),  em tanques-rede. O experimento foi realizado em delineamento inteiramente casualizado, com quatro tratamentos (2,3, 2,9, 3,5 e 4,1% de arginina em relação à matéria seca na dieta) e três repetições, em 12 tanques-rede de 8 m3, com 4.000 tilápias revertidas sexualmente (63±20 g, 500 peixes m-3). Determinaram-se o desempenho produtivo e a saúde dos peixes. Avaliaram-se os parâmetros bioquímicos e hematoimunológicos e os aspectos morfológicos das brânquias e do fígado. A inclusão de arginina não proporcionou diferenças significativas no desempenho produtivo. Porém, a suplementação de arginina a 3,5% de concentração melhorou os parâmetros bioquímicos e de contagem de leucócitos, tendo consequentemente melhorado o sistema imunológico. A concentração de arginina a 4.1% causou degeneração lipídica, representada pelo aumento dos níveis da alanina aminotransferase e  pela diminuição dos níveis de albumina, ureia, lactato e glicose. A suplementação com arginina acima de 2,3% e abaixo de 3,5%, nas dietas de tilápias criadas em tanques-rede, promove melhoras no sistema imunológico dos peixes, sem provocar efeitos morfológicos e fisiológicos deletérios

EFEITO DA TOXICIDADE AGUDA DA GASOLINA EM ALEVINOS DE ACARÁ BANDEIRA (Pterophyllum scalare)

Polycyclic and monocyclic hydrocarbons, constituents of petroleum compounds, stand out by its toxic action of fossil fuels for aquatic organisms. Thus, this study aimed to determine the lethal concentration (LC50) of gasoline to Pterophyllum scalare, evaluating the survival and behavior of fish changes. For this, P. scalare fingerlings (1.41 ± 0.1 cm and 0.039 ± 0.001 g) were used in a reference substance sensitivity test (KCl) and for the definitive test. The experiment was carried out in a completely randomized design with six dilutions of gasoline (0.05, 0.1, 0.15, 0.2, 0.25 and 0.3% v/v) and a control, all with three repetitions lasting 96 hours. To determine the values of CL(I)50 the Trimmed Spearman Karber method was used and classified according to the description proposed by Cesteb.  The sensitivity determined for P. scalare fingerlings was (LC50-96h) 0.93 g.L-1, whereas the estimated 50% (LC50-96h) lethal concentration for gasoline was 0.14%, in which the dilution of 0, 3% had 100% mortality before 24 hours of exposure. Gasoline is classified as a very toxic xenobiotic, capable of changing the behavior of fingerlings, in which erratic swimming, agitation, proximity to the surface and rapid opercular beating were observed. Therefore, gasoline represents a risk to the aquatic environment resulting from the intoxication of organisms, causing behavioral changes and mortality.Keywords: Gasoline; ecotoxicity; angelfish; hydrocarbons.Os hidrocarbonetos policíclicos e monocíclicos, constituintes dos compostos derivados de petróleo, são as principais substâncias químicas responsáveis pela toxicidade dos combustíveis fósseis nos organismos aquáticos. Desta forma, o presente estudo objetivou determinar a concentração letal (CL50) da gasolina em alevinos de acará bandeira (Pterophyllum scalare), avaliando-se a sobrevivência e as alterações comportamentais dos peixes. Para tanto, foram usados alevinos de P. scalare (1,41 ± 0,1 cm e 0,039 ± 0,001 g) em ensaio de sensibilidade com substância referência (KCl) e para o teste definitivo. No qual, foi realizado um delineamento inteiramente casualizado com seis diluições de gasolina (0,05; 0,1; 0,15; 0,2; 0,25 e 0,3% v/v) e um controle, todos com três repetições com duração de 96 horas. Para determinar os valores de CL(I)50 foi utilizado o método de Trimmed Spearman Karber e classificado segundo a descrição proposta por Cesteb. A sensibilidade determinada para os alevinos de P. scalare foi de (CL50-96h) 0,93 g.L-1, já a concentração letal 50% (CL50-96h) estimada para a gasolina foi de 0,14%, ao qual a diluição de 0,3% teve mortalidade de 100% antes de 24 horas de exposição. A gasolina é classificada como um xenobiótico muito tóxico, capaz de alterar o comportamento dos alevinos, no qual foram observadas natação errática, agitação, proximidade a superfície e batimento opercular rápido. Portanto, a gasolina representa um risco ao ambiente aquático decorrente da intoxicação dos organismos, causando alterações comportamentais e a mortalidade.Palavras-chave: Gasolina, ecotoxicidade, acará bandeira, hidrocarbonetos

Estimating the global conservation status of more than 15,000 Amazonian tree species

Estimates of extinction risk for Amazonian plant and animal species are rare and not often incorporated into land-use policy and conservation planning. We overlay spatial distribution models with historical and projected deforestation to show that at least 36% and up to 57% of all Amazonian tree species are likely to qualify as globally threatened under International Union for Conservation of Nature (IUCN) Red List criteria. If confirmed, these results would increase the number of threatened plant species on Earth by 22%. We show that the trends observed in Amazonia apply to trees throughout the tropics, and we predict thatmost of the world’s >40,000 tropical tree species now qualify as globally threatened. A gap analysis suggests that existing Amazonian protected areas and indigenous territories will protect viable populations of most threatened species if these areas suffer no further degradation, highlighting the key roles that protected areas, indigenous peoples, and improved governance can play in preventing large-scale extinctions in the tropics in this century

Geographic patterns of tree dispersal modes in Amazonia and their ecological correlates

Aim: To investigate the geographic patterns and ecological correlates in the geographic distribution of the most common tree dispersal modes in Amazonia (endozoochory, synzoochory, anemochory and hydrochory). We examined if the proportional abundance of these dispersal modes could be explained by the availability of dispersal agents (disperser-availability hypothesis) and/or the availability of resources for constructing zoochorous fruits (resource-availability hypothesis). Time period: Tree-inventory plots established between 1934 and 2019. Major taxa studied: Trees with a diameter at breast height (DBH) ≥ 9.55 cm. Location: Amazonia, here defined as the lowland rain forests of the Amazon River basin and the Guiana Shield. Methods: We assigned dispersal modes to a total of 5433 species and morphospecies within 1877 tree-inventory plots across terra-firme, seasonally flooded, and permanently flooded forests. We investigated geographic patterns in the proportional abundance of dispersal modes. We performed an abundance-weighted mean pairwise distance (MPD) test and fit generalized linear models (GLMs) to explain the geographic distribution of dispersal modes. Results: Anemochory was significantly, positively associated with mean annual wind speed, and hydrochory was significantly higher in flooded forests. Dispersal modes did not consistently show significant associations with the availability of resources for constructing zoochorous fruits. A lower dissimilarity in dispersal modes, resulting from a higher dominance of endozoochory, occurred in terra-firme forests (excluding podzols) compared to flooded forests. Main conclusions: The disperser-availability hypothesis was well supported for abiotic dispersal modes (anemochory and hydrochory). The availability of resources for constructing zoochorous fruits seems an unlikely explanation for the distribution of dispersal modes in Amazonia. The association between frugivores and the proportional abundance of zoochory requires further research, as tree recruitment not only depends on dispersal vectors but also on conditions that favour or limit seedling recruitment across forest types

Mapping density, diversity and species-richness of the Amazon tree flora

Using 2.046 botanically-inventoried tree plots across the largest tropical forest on Earth, we mapped tree species-diversity and tree species-richness at 0.1-degree resolution, and investigated drivers for diversity and richness. Using only location, stratified by forest type, as predictor, our spatial model, to the best of our knowledge, provides the most accurate map of tree diversity in Amazonia to date, explaining approximately 70% of the tree diversity and species-richness. Large soil-forest combinations determine a significant percentage of the variation in tree species-richness and tree alpha-diversity in Amazonian forest-plots. We suggest that the size and fragmentation of these systems drive their large-scale diversity patterns and hence local diversity. A model not using location but cumulative water deficit, tree density, and temperature seasonality explains 47% of the tree species-richness in the terra-firme forest in Amazonia. Over large areas across Amazonia, residuals of this relationship are small and poorly spatially structured, suggesting that much of the residual variation may be local. The Guyana Shield area has consistently negative residuals, showing that this area has lower tree species-richness than expected by our models. We provide extensive plot meta-data, including tree density, tree alpha-diversity and tree species-richness results and gridded maps at 0.1-degree resolution

Geography and ecology shape the phylogenetic composition of Amazonian tree communities

Aim: Amazonia hosts more tree species from numerous evolutionary lineages, both young and ancient, than any other biogeographic region. Previous studies have shown that tree lineages colonized multiple edaphic environments and dispersed widely across Amazonia, leading to a hypothesis, which we test, that lineages should not be strongly associated with either geographic regions or edaphic forest types. Location: Amazonia. Taxon: Angiosperms (Magnoliids; Monocots; Eudicots). Methods: Data for the abundance of 5082 tree species in 1989 plots were combined with a mega‐phylogeny. We applied evolutionary ordination to assess how phylogenetic composition varies across Amazonia. We used variation partitioning and Moran's eigenvector maps (MEM) to test and quantify the separate and joint contributions of spatial and environmental variables to explain the phylogenetic composition of plots. We tested the indicator value of lineages for geographic regions and edaphic forest types and mapped associations onto the phylogeny. Results: In the terra firme and várzea forest types, the phylogenetic composition varies by geographic region, but the igapó and white‐sand forest types retain a unique evolutionary signature regardless of region. Overall, we find that soil chemistry, climate and topography explain 24% of the variation in phylogenetic composition, with 79% of that variation being spatially structured (R2 = 19% overall for combined spatial/environmental effects). The phylogenetic composition also shows substantial spatial patterns not related to the environmental variables we quantified (R2 = 28%). A greater number of lineages were significant indicators of geographic regions than forest types. Main Conclusion: Numerous tree lineages, including some ancient ones (>66 Ma), show strong associations with geographic regions and edaphic forest types of Amazonia. This shows that specialization in specific edaphic environments has played a long‐standing role in the evolutionary assembly of Amazonian forests. Furthermore, many lineages, even those that have dispersed across Amazonia, dominate within a specific region, likely because of phylogenetically conserved niches for environmental conditions that are prevalent within regions