Indications that fishers perceive socio-environmental problems related to hydroelectric plants in the Tocantins river, Brazil

Hydroelectric dams (HEDs) cause significant socio-environmental damage such as reduced fish diversity, population displacement and health problems. The fishers have extensive local ecological knowledge that can be used to improve understanding of the impacts of HEDs. Therefore, the objective of this study was to verify and evaluate the perceptions of fishers about the impacts caused by the HEDs in the Tocantins River. For this, 25 fishers were interviewed using a questionnaire with 22 questions. Data analyses were performed considering descriptive analysis of the responses. There was convergence in the responses of fishers who perceived the decrease in fish diversity after the construction of the HEDs, including fish of commercial interest, which is linked to a decrease in income and decreased food security for these families. In addition, the fishers noted symptoms that may be a consequence of mercury contamination, and diarrhea as a possible consequence of decreased water quality. Despite all these socio-environmental losses, the fishers report a lack of prior consultation, and low representativeness and transparency in the decision-making process that preceded the construction of HEDs. In general, the fishers perceived themselves as being strongly affected from the socio-environmental point of view and do not cite any benefits offered to the community from these projects

Patterns of nuclear and chloroplast genetic diversity and structure of manioc along major Brazilian Amazonian rivers

Background and Aims Amazonia is a major world centre of plant domestication, but little is known about how the crops were dispersed across the region. Manioc (Manihot esculenta) was domesticated in the south-western Amazon basin, and is the most important staple food crop that originated in Amazonia. Current contrasting distributions may reflect distinct histories of dispersal of bitter and sweet manioc landraces. To produce new insights into the evolutionary history of the crop, we investigated the contemporary genetic diversity and structure of bitter and sweet manioc along major Amazonian rivers. Methods The patterns of genetic structure and diversity of wild and cultivated sweet and bitter manioc with four chloroplast and 14 nuclear microsatellite markers were evaluated. Results were interpreted in terms of the crop's dispersal. Key results No phylogeographic patterns among rivers were detected, and genetic structure among rivers was confounded by the bitter-sweet divergence. However, differences in the distribution of nuclear diversity and somewhat distinctive patterns of genetic structure across rivers were observed within bitter and sweet manioc. Conclusions Various pre-Columbian and post-European conquest events in the history of Amazonian occupation may explain the absence of clearer patterns of genetic structure. However, the wide distribution of the most common chloroplast haplotype agrees with an early dispersal of manioc across Brazilian Amazonia. Furthermore, differences in genetic structure and in the spatial distribution of genetic diversity suggest that bitter and sweet manioc had distinct dispersal histories. Knowledge about how prehistoric and contemporary Amazonian peoples manage their crops is valuable for the maintenance and conservation of the impressive diversity of their native crops. © 2018 The Author(s). Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved

Influência da técnica de quebra de dormência, substrato e tamanho da semente na germinação do taperebá procedentes de duas populações nativas da Amazônia Central

Spondias mombin (taperebá) é uma espécie frutífera da Amazônia, com grande potencial de uso agroindustrial e consumo “in natura”. No entanto, alguns problemas fitotécnicos persistem, dentre os quais a germinação irregular e sua má distribuição ao longo do tempo. Neste sentido, avaliamos a influência da técnica de quebra de dormência, substrato e tamanho da semente na germinação do taperebá procedentes de duas populações nativas da Amazônia Central. O estudo foi desenvolvido em casa de vegetação no Instituto de Ciências Exatas e Tecnologia (ICET) – UFAM, no município de Itacoatiara, Amazonas.  A amostragem dos frutos foi realizada em duas localidades distintas de populações nativas. De cada local de amostragem utilizamos 100 frutos, sendo divididos em quatro amostras para realizar a caracterização morfoagronômica, determinando o peso, diâmetro, comprimento do fruto, peso da casca sem polpa, porcentagem de polpa, teor de umidade, diâmetro da semente, comprimento e peso da semente. Foi utilizado o delineamento experimental em blocos casualizados em esquema fatorial 4x2x2, totalizando 16 tratamentos por local de coleta. Os fatores estudados foram, quebra de dormência (corte distal, temperatura à 100oC/5 minutos, temperatura à 50oC/5 minutos, testemunha), substrato (areia e terra da mata + esterco + cinza) e tamanho do endocarpo (grande e pequeno). Os resultados demonstraram que as sementes de taperebá podem ser influenciadas pelos locais de procedências, afetando as variáveis de emergência, velocidade e o tempo médio de emergência

Spatial genetic structure, genetic diversity and pollen dispersal in a harvested population of Astrocaryum aculeatum in the Brazilian Amazon

Abstract\ud \ud Background\ud \ud Astrocaryum aculeatum is a palm tree species native to the tropical regions of South America, exploited commercially by local farmers for the pulp extracted from its fruits. The objective of this research was to compare the genetic diversity between adult plants and seedlings from open-pollinated seeds, quantify the pollen flow and dispersal, the spatial genetic structure, and the effective size of a population that has been continuously harvested for its fruits. The study was carried out in a natural population of A. aculeatum distributed over approximately 8 ha in the State of Amazonas (Brazil), separated by 400 m from the closest neighboring population. In total, 112 potential pollen donors, 12 mother plants and 120 offspring were mapped and genotyped.\ud \ud \ud Results\ud Genetic diversity was high for parents and the offspring. The fixation indexes for adults (F = -0.035) and offspring (F = -0.060) were negative and not significant. A significant spatial genetic structure was detected for the adult plants (up to the distance of 45 m) indicating short-distance seed dispersal. Paternity analysis detected 9.2 % of pollen immigration and the average distance of pollination within the population was 81 m. The average effective pollination neighborhood area between plants was 1.51 ha.\ud \ud \ud Conclusions\ud Our results indicate that substantial introduction of new alleles has occurred in the population through pollen immigration, contributing to the maintenance of genetic diversity. Conservation efforts aimed at maintaining the gene pool of the current population or establishing new populations should utilize offspring from mother plants selected to be spaced by at least 50 m to prevent collecting seeds from relatives.The authors thank the Fundação de Amparo à Pesquisa do Estado do Amazonas\ud (FAPEAM) for a scholarship to SLFR and supporting the project "Publicação de\ud Artigos Científicos em Genética e Melhoramento de Plantas" - PAPAC (process\ud 062.02685 / 2014); the Conselho Nacional de Desenvolvimento Científico e\ud Tecnológico (CNPq) for scholarships to AMS, MTGL, EAV; the Embrapa Amazônia\ud Ocidental through the project “Pesquisa, desenvolvimento e inovação em\ud palmáceas para a produção de óleo e aproveitamento econômico de coprodutos\ud e resíduos – PROPALMA” (process 01.10.0343.00); and the Coordenação\ud de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) - Programa de\ud Excelência Acadêmica (Proex) of the Genetics Department of ESALQ-USP for\ud supporting this research; and the Laboratório Temático de Biologia Molecular -\ud Instituto Nacional de Pesquisas da Amazônia (LTBM – INPA) for its facilities. The\ud authors also thank Mrs. Angela Mary Wray for the great contribution in the English\ud language and two anonymous reviewers for the excellent suggestions in the\ud manuscript

Genetic structure and gene flow in natural populations of tucum palm by microsatellite aiming at the management and conservation of the species

O tucumã-do-Amazonas (Astrocaryum aculeatum), da família Arecaceae, é uma espécie com ocorrência na Amazônia Ocidental e Central brasileira. Seu fruto é muito apreciado na região amazônica que consome a polpa na forma fresca. Sua produção é feita pelos agricultores extrativistas. Não existem informações dos parâmetros de diversidade e estrutura genética das populações naturais desta espécie, fundamental para o estabelecimento de estratégias adequadas no uso deste recurso genético, e para aumentar a eficiência da domesticação e seleção para um programa de melhoramento genético. Não é conhecido também como este extrativismo pode estar influenciando a diversidade entre estas populações ao nível dos genitores e progênies, o fluxo gênico e a estrutura genética espacial. Assim, o objetivo desta pesquisa foi caracterizar a estrutura e a diversidade genética de populações de A. aculeatum no Estado do Amazonas, utilizando marcadores microssatélites. Como objetivos específicos o estudo visou desenvolver iniciadores de microssatélites para A. aculeatum; avaliar a diversidade e a estrutura genética; determinar o fluxo gênico, bem como o grau de parentesco, a estrutura genética espacial (EGE) e o coeficiente de coancestria numa população. Os iniciadores de microssatélites foram isolados a partir de uma biblioteca genômica enriquecida e caracterizados usando 40 amostras provenientes de duas populações selvagens. Foram identificados 14 iniciadores de microssatélites, mostrando um alto polimorfismo nas populações avaliadas. Para estimar a diversidade e estrutura genética foram utilizadas amostras de material vegetal de 218 plantas distribuídas em 15 populações, localizadas em 14 municípios do estado de Amazonas. Foram identificados 101 alelos nos iniciadores, com média de 10,1 alelos. As médias das heterozigosidades observadas (HO) foram superiores às esperadas (HE) ao nível de população (HO=0,639, HE=0,557) e locos (HO=0,639; HE=0,594). Os baixos valores de FST (0,07) mostraram uma moderada estrutura populacional e a análise Bayesiana indicou um agrupamento mais adequado de k=4, o que foi confirmado pelas análises de PCoA. Para realizar o fluxo gênico, EGE e coeficiente de coancestria foram utilizadas 244 amostras de material vegetal, distribuídas entre 112 possíveis genitores, 12 matrizes e 120 progênies numa população. Foi detectada EGE significativa para os adultos até a distância de 50 m, indicando dispersão de sementes a curtas distâncias. A análise de paternidade detectou 9,2% de imigração de pólen. Não foram detectadas autofecundações e a distância média de polinização dentro da população foi de 81 m. Os índices de diversidade genética confirmaram a estratégia reprodutiva por alogamia da espécie, com níveis elevados de heterozigotos nas populações, e a estrutura genética sugere que a espécie teria iniciado o processo de formação das subpopulações há pouco tempo, tendo sido influenciada antes e após o início do desmatamento. O fluxo gênico detectado indica que a entrada de alelos na população através da imigração de pólen está contribuindo para manutenção da diversidade genética da população. Com relação à conservação da espécie, esta deve ser realizada ao nível das bacias hidrográficas, direcionando políticas de manejo para as bacias hidrográficas da Amazônia. Entretanto, dentro da população é importante a renovação com novas progênies selecionadas a partir de um espaçamento mínimo de 50 m entre plantas matrizes para diminuir as probabilidades de coletar sementes de plantas parentes.The tucum palm (Astrocaryum aculeatum), family Arecaceae, is a species occurring in Western and Central Brazilian Amazon. Its fruit is widely appreciated in the Amazon region that consumes the pulp in fresh form. Its production is made by extractive farmers. There is no information on the genetic diversity and structure of natural populations of this species, fundamental to establishing adequate strategies in the use of this genetic resource, increase the efficiency of domestication and selection for a breeding program. It is also unknown the way this extrativism may be influencing to diversity of these populations at the level of the parents and offspring, as well as gene flow and spatial genetic structure. Therefore, the objective of this research was to characterize the structure and genetic diversity of populations of A. aculeatum in Amazonas State, using microsatellite markers. As specific objectives, the study aimed to develop microsatellite primers for A. aculeatum; evaluate the genetic diversity and structure; determine the gene flow, the degree of relationship or kinship, the spatial genetic structure (SGS) and the coefficient of coancestry in one population. The loci were isolated from a microsatellite-enriched genomic library and were characterized using 40 samples coming from two wild populations. Fourteen microsatellite primers were identified, showing a high polymorphism in the populations evaluated. To estimate the genetic diversity and structure we used samples of plant material from 218 plants distributed in 15 populations located in 14 municipalities of the state of Amazonas. A total of 101 alleles were identified in the primers, with an average of 10.1 alleles. The averages of the observed heterozygosities (HO) were higher than the expected heterozygosities (HE) at the population (HO=0.639; HE=0.557) and loci (HO=0.639; HE=0.594) levels. The low values of FST (0.07) showed a moderate population structure and the Bayesian analysis indicated as the most suitable a cluster of k=4, confirmed by the groups formed in the PCoA. To conduct gene flow, SGS and the coefficient of coancestry, 244 samples of plant material were used, distributed among 112 possible progenitors, 12 matrices and 120 progenies in a population. A significant SGS was detected for adult trees up to the distance of 50 m, indicating seed dispersal over short distances. Paternity analysis indicated 9.2% of pollen immigration. Selfing was not detected and the average distance of pollination within the population was 81 m. The genetic diversity indices confirmed the outcrossing reproductive strategy of the species with high levels of heterozygotes in the populations, and the genetic structure suggests that the species would have started the process of formation of subpopulations a short time ago, being influenced before and after the start of deforestation. The gene flow detected indicates that the entry of alleles in the population through pollen immigration is contributing to the maintenance of genetic diversity of the population. With respect to the conservation of the species, it should be performed at the level of the river basins, directing management policies for the river basins of the Amazon. However, within the population it is important to renew with new progenies selected from a minimum spacing of 50 m between plant matrices to decrease the probability of collecting seeds from plant relatives

Highly structured genetic diversity of Bixa orellana var. urucurana, the wild ancestor of annatto, in Brazilian Amazonia

Annatto (Bixa orellana L.) is a tropical American crop, commercially valuable due to its application in the food and cosmetics industries as a natural dye. The wild ancestor of cultivated annatto is B. orellana var. urucurana. Although never cultivated, this variety occurs in open forests and anthropogenic landscapes, and is always associated with riparian environments. In this study, we evaluated the genetic diversity and structure of B. orellana var. urucurana populations in Brazilian Amazonia using 16 microsatellite loci. We used Ecological Niche Modeling (ENM) to characterize the potential geographical range of this variety in northern South America. We analyzed 170 samples from 10 municipalities in the states of Rondônia, Pará and Roraima. A total of 194 alleles was observed, with an average of 12.1 alleles per locus. Higher levels of expected (HE) than observed (HO) heterozygosities were found for all populations. Bayesian analysis, Neighbor-Joining dendrograms and PCAs suggest the existence of three strongly structured groups of populations. A strong and positive correlation between genetic and geographic distances was found, suggesting that genetic differentiation might be caused by geographic isolation. From species distribution modelling, we detected that South Rondônia, Madre di Dios River basin, Llanos de Mojos, Llanos de Orinoco and eastern Ecuador are highly suitable areas for wild annatto to occur, providing additional targets for future exploration and conservation. Climatic adaptation analyses revealed strong differentiation among populations, suggesting that precipitation plays a key role in wild annatto's current and potential distribution patterns

DISTRIBUI\uc7\uc3O E CRESCIMENTO DE Garcinia brasiliensis Mart. e Hevea spruceana (Benth.) M\ufcll. Arg. EM UMA FLORESTA INUND\uc1VEL EM MANAUS, AMAZONAS

This study assessed the distribution and growth of two tree species in a seasonal mixed-water inundation forest near the city of Manaus, and determined the annual growth rates and ages of trees. The aboveground wood biomass was estimated for each population. Eight plots of 25 x 25 m were established, where all individuals of the species Garcinia brasiliensis and Hevea spruceana with heights 65 1.0 m were inventoried and mapped. The levels of inundation were measured on all individuals, while the relative photosynthetically active radiation (rPAR) was measured in individuals 64 10 cm diameter at breast height (dbh). For each individual, the basal area was determined, and the tree volume estimated. Tree ages and the radial increment rate were determined by using dendrochronological methods. In total, 105 individuals were recorded. In both populations, most individuals presented dbh smaller than 10 cm. Hevea spruceana presented more individuals (n = 80), and higher rates of radial increment, while Garcinia brasiliensis (n = 25) presented higher mean age. The duration and height of inundation and the levels of rPAR were different for each population. It was detected significant correlations between dbh and tree heights, and between dbh and tree age. The micro-topographical variations appear to exert effects on the structure population and on the distribution of the studied species. Despite the low rPAR values and variations recorded within the study site, the different light requirements in each species suggest different ecological niches.Este estudo descreve a distribui\ue7\ue3o e determina a taxa anual de crescimento e a idade das \ue1rvores de Garcinia brasiliensis e de Hevea spruceana em uma floresta inund\ue1vel na regi\ue3o de Manaus. Oito parcelas cont\uedguas de 25 x 25 metros foram instaladas, onde todos os indiv\uedduos das duas esp\ue9cies com altura 65 1,0 m foram mapeados. O di\ue2metro, a altura das \ue1rvores e os n\uedveis de inunda\ue7\ue3o foram registrados para todos os indiv\uedduos. A radia\ue7\ue3o fotossinteticamente ativa (RFA) foi medida em indiv\uedduos da regenera\ue7\ue3o ( 64 10 cm di\ue2metro a altura do peito -dap). Foram calculadas a \ue1rea basal e o volume para cada indiv\uedduo, e determinados o padr\ue3o de crescimento e a idade das \ue1rvores utilizando m\ue9todos dendrocronol\uf3gicos. Um total de 105 indiv\uedduos foi amostrado, a maioria na classe de regenera\ue7\ue3o. Hevea spruceana apresentou o maior n\ufamero de indiv\uedduos (n=80), as maiores taxas de crescimento em dap e em altura. Garcinia brasiliensis (n=25) apresentou idade, dap e altura maiores do que Hevea spruceana. Ambas as esp\ue9cies foram sujeitas a diferentes n\uedveis de inunda\ue7\ue3o e de radia\ue7\ue3o. A estrutura populacional e a distribui\ue7\ue3o dos indiv\uedduos dessas esp\ue9cies mostram ser, aparentemente, influenciadas pelas varia\ue7\uf5es na topografia local em pequena escala. Os diferentes requerimentos por radia\ue7\ue3o destas esp\ue9cies sugerem ocupa\ue7\ue3o de diferentes nichos ecol\uf3gicos

DISTRIBUIÇÃO E CRESCIMENTO DE Garcinia brasiliensis Mart. e Hevea spruceana (Benth.) Müll. Arg. EM UMA FLORESTA INUNDÁVEL EM MANAUS, AMAZONAS

This study assessed the distribution and growth of two tree species in a seasonal mixed-water inundation forest near the city of Manaus, and determined the annual growth rates and ages of trees. The aboveground wood biomass was estimated for each population. Eight plots of 25 x 25 m were established, where all individuals of the species Garcinia brasiliensis and Hevea spruceana with heights ≥ 1.0 m were inventoried and mapped. The levels of inundation were measured on all individuals, while the relative photosynthetically active radiation (rPAR) was measured in individuals < 10 cm diameter at breast height (dbh). For each individual, the basal area was determined, and the tree volume estimated. Tree ages and the radial increment rate were determined by using dendrochronological methods. In total, 105 individuals were recorded. In both populations, most individuals presented dbh smaller than 10 cm. Hevea spruceana presented more individuals (n = 80), and higher rates of radial increment, while Garcinia brasiliensis (n = 25) presented higher mean age. The duration and height of inundation and the levels of rPAR were different for each population. It was detected significant correlations between dbh and tree heights, and between dbh and tree age. The micro-topographical variations appear to exert effects on the structure population and on the distribution of the studied species. Despite the low rPAR values and variations recorded within the study site, the different light requirements in each species suggest different ecological niches.Este estudo descreve a distribuição e determina a taxa anual de crescimento e a idade das árvores de Garcinia brasiliensis e de Hevea spruceana em uma floresta inundável na região de Manaus. Oito parcelas contíguas de 25 x 25 metros foram instaladas, onde todos os indivíduos das duas espécies com altura ≥ 1,0 m foram mapeados. O diâmetro, a altura das árvores e os níveis de inundação foram registrados para todos os indivíduos. A radiação fotossinteticamente ativa (RFA) foi medida em indivíduos da regeneração (≤ 10 cm diâmetro a altura do peito –dap). Foram calculadas a área basal e o volume para cada indivíduo, e determinados o padrão de crescimento e a idade das árvores utilizando métodos dendrocronológicos. Um total de 105 indivíduos foi amostrado, a maioria na classe de regeneração. Hevea spruceana apresentou o maior número de indivíduos (n=80), as maiores taxas de crescimento em dap e em altura. Garcinia brasiliensis (n=25) apresentou idade, dap e altura maiores do que Hevea spruceana. Ambas as espécies foram sujeitas a diferentes níveis de inundação e de radiação. A estrutura populacional e a distribuição dos indivíduos dessas espécies mostram ser, aparentemente, influenciadas pelas variações na topografia local em pequena escala. Os diferentes requerimentos por radiação destas espécies sugerem ocupação de diferentes nichos ecológicos