Trombetas Research Articles

Institution-based access implications faced by traditional communities in Amazônia: towards co-managing protected areas and Terms of Compromise for socio-biodiversity

Given limitations of resource and market access reported by traditional local communities and a limiting institutional environment for socio-biodiversity in Amazônia, the main question is: how do institutions (re)shape natural resource and market access by Quilombolas in the protected area of the Trombetas River Biological Reserve (TRBR) and the Implications of the TRBR Term of Compromise (TC) – a formal institution written by the Chico Mendes Institute for Biodiversity Conservation (ICMBio) – on livelihood-relevant access to socio-biodiversity products (Brazil nuts) and markets. Methods include semi-structured interviews (n=89) focusing on Non-timber forest products gatherers, as well as observation and focus-group interviews for data triangulation. An analytical framework is developed, combining access theory, institutions and property rights scholarship. Findings reveal that the TC overwrites institutionalised norms of Quilombola communities, which regulated such livelihood-relevant access long before the TRBR establishment (1979). The TC not only formalises BN use but also unintentionally restricts natural resources and market access, limiting Quilombolas’ bioeconomy-benefits.

Changes in the landscape, threats, and the struggle of the quilombola communities from Alto Trombetas for their territories

ABSTRACT This study addresses landscape changes in the quilombola territories of the communities Alto Trombetas 1 and 2, on the banks of the Trombetas River. It also points out transformations that have taken place since the creation of federal conservation units and the installation of bauxite mining activities in the region. The production and management of overlaps involves a heterogeneous network of state actors, artifacts, and socio-technical apparatuses that materialize interventions in the landscape, in a web of government bodies, norms, and a discourse favorable to progress and profit. This overlap has made the communities organize themselves against the invasion of their lands and struggle constantly to give visibility to the effects of mining and conservation units. We conclude that the history of questionable interventions from different sectors of the state has compromised the coexistence of quilombola territories with other lives in the region. Also, the lack of monitoring and studies focused on the effects of mining on quilombola communities shows how environmental racism falls upon racialized bodies and territories. However, quilombola communities continue to resist in their ancestral territories.

‘From the sky to the ground’: fishers' knowledge, landscape analysis and hydrological data indicate long-term environmental changes in Amazonian clear water rivers

Fishers possess detailed local ecological knowledge (LEK) which can be a valuable resource for tracking long-term environmental changes in less studied tropical rivers. Our goal was to investigate such changes in three clear water rivers in the Brazilian Amazon, focusing on hydrology, water quality and land cover. Additionally, we aimed to compare these changes among three rivers (Trombetas, Tapajós and Tocantins) representing a potential gradient of environmental changes. We interviewed 129 fishers (67 in Tapajós, 33 in Tocantins and 29 in Trombetas), and analyzed temporal series on land cover and hydrology respectively through maps produced by the project MapBiomas, and data from the Brazilian National Water Agency across the last 34 years (from 1985 to 2019). The complementary analyses of these three databases (mapping, hydrological data and fishers' knowledge) revealed environmental changes in the studied rivers. The maps showed a gradient of anthropic changes on land cover, from the less altered Trombetas river, the moderately altered Tapajós and the more intensely changed landscape in the Tocantins River. Fishers from the Tocantins River reported a greater variety of negative changes in water quality related to anthropic actions, such as dams, deforestation, and pollution. Additionally, most fishers indicated hydrological changes making the Tocantins River drier in more recent years, which would cause negative effects on fish populations. In the Tapajós River, fishers mentioned more varied hydrological patterns and negative effects on water quality linked to mining activities, whereas in Trombetas fishers perceived increased floods. The changes mentioned by the interviewed fishers matched observed trends from hydrological data indicating a trend of increasing droughts in the more impacted Tocantins River. Fishers' knowledge provided exclusive ‘on the ground’ data to track long-term changes on local hydrology and water quality, as well as inform the effects of these changes on fish and fisheries.

Priority areas and integrated actions for the conservation of Amazonian turtle populations historically over-exploited by humans

The definition of priority areas for conservation and integrated management actions are essential for the effective maintenance and recovery of natural populations, especially for species overexploited by humans. Amazonian chelonians are a food resource historically used by people, resulting in the decline of species populations and worsening the risk of local extinctions. In this paper, we establish priority areas and define integrated conservation actions for populations of three Amazonian chelonians most threatened by human consumption in Brazil (Podocnemis expansa, P. unifilis and P. sextuberculata). To do so, we used 15 prioritization criteria (ecological, logistical and socioeconomic) estimated with 30 years monitoring data in 15 areas by the Amazon Chelonian Program (in portugues Projeto Quelonios da Amazonia, PQA). Each criterion presented four levels of priority with scores increasing according to the relevance for conservation of chelonian populations. The sum of the scores obtained in each area of the PQA allowed a ranking and four categories of importance for conservation to be defined. We also analyzed the similarity of scores among areas of the PQA and among the prioritization criteria to evaluate the application of integrated conservation action strategies. The areas of PQA were classified as Extremely Important for Conservation (Rebio Trombetas River, Middle Xingu River, Middle Araguaia River, Upper Guaporé River), Very Highly Important for Conservation (Middle Purus River, Middle Juruá River, Crixás-Açu River Mouth, Sub-middle Tapajós River); Highly Important for Conservation (Sub-Middle Araguaia River, Amazonas River Mouth, Middle Mortes River); and Important for Conservation (Middle Guaporé River, Lower Branco River, Flechal River, Afuá River). The prioritization and similarity analyses can support the development of a national integrated plan of conservation actions to reduce the overexploitation of Amazon chelonian populations, according to the ecological, logistical and socioeconomic needs of each PQA area.

PHYTOPLANKTON BIOMASS INCREASES IN A SILT-IMPACTED AREA IN AN AMAZONIAN FLOOD-PLAIN LAKE OVER 15 YEARS

Tailings from bauxite mining in Porto Trombetas (Pará state, Central Amazonia, Brazil) was discharged (1979–1989) into Batata Lake affecting about 30% of its area. The lake belongs to a clear-water flood-plain system along the Trombetas River, a tributary of the Amazon River. Siltation is the main perceived factor impacting aquatic and flooded communities. Besides natural regeneration, a program to restore a section of igapó forest in the impacted area (IA) has been conducted since 1991. Decreased light is the main factor reducing total phytoplankton biomass (PhyBM) in IA. We hypothesized that PhyBM in IA increases over time because of the improvement of the underwater light conditions due to the natural regeneration and restoration. We sampled quarterly PhyBM and limnological variables (depth, transparency, temperature, pH, conductivity, dissolved oxygen, turbidity, suspended solids, total Kjeldahl nitrogen, and total phosphorus), over 15 years (2005–2019) at eight sampling sites in the two areas (N = 349). We also obtained daily climatic and hydrologic data. PhyBM was higher in NIA than in IA. The temporal trend in the annual mean of PhyBM increased significantly over time only in the IA, approximating the NIA values, confirming our general hypothesis. The increase of PhyBM in the IA was negatively related to the residual light attenuation caused by non-phytoplankton turbidity and to total phosphorus, and positively to air temperature and site depth (p < 0.05; Marginal r2 = 0.18; Conditional r2 = 0.29). Instead, in NIA, PhyBM was explained only by the increase in air temperature (p < 0.05; Marginal r2 = 0.15; Conditional r2 = 0.34). We concluded that the PhyBM in the IA positively responds to the synergy between increasing light availability, air temperature, and site depth, and decreasing total phosphorus concentrations, regardless of hydrologic phase.

ICHTHYOPLANKTON COMMUNITY IN LAGOONS OF THE TAPAJÓS AND TROMBETAS RIVERS, EASTERN AMAZON

We evaluated the structure of the ichthyoplanktonic assemblage (taxonomic composition, abundance, developmental stages, and relationship with local environmental variables) in marginal lagoons located in the clearwater Tapajós and Trombetas rivers, Amazon Basin, Brazil during periods of high water (rising waters and flooding). Samples were collected by means of horizontal drags in the subsurface of the water with a plankton net (300 µm mesh). Sorting, counting, identification of biological material, and classification of embryonic and larval stages were performed under a stereoscopic microscope. A total of 122 eggs and 2,813 fish larvae were captured and distributed in nine orders, 18 families, 20 genera, and 26 species. Of these, more than 75% are considered sedentary or short-distance migrants and more than 50% are of commercial interest. The results revealed fluctuating patterns of abundance and species composition between the lagoons of the two rivers. The ichthyoplankton community in the lagoons consisted mainly of larvae of native pelagic fish belonging to the Engraulidae family and larvae of benthic fish such as Eleotridae, making up more than 85% of the individuals captured in the study area. In addition to these two groups, some larvae of piranha species (Pygocentrus nattereri) stood out due to their high densities in the Tapajós river lagoons and croaker larvae (Plagioscion spp.) in the Trombetas river lagoons. The highest larval densities were recorded during the night with significant variations recorded in species composition. The presence of all stages of larval development indicates that these biotopes enable growth and are essential for the biological recruitment of fish species in the region. The ichthyoplankton showed a low correlation with the limnological variables, however, the patterns of abundance and composition of fish larval assemblages in the lagoons of the Tapajós and Trombetas rivers were preliminarily elucidated, although additional work is needed to assess the effects on survival and recruitment

Vulnerabilidade e saúde de mulheres quilombolas em uma área de mineração na Amazônia

Abstract Vulnerability encompass different factors that contribute to exposing individuals and groups to the illness processes. In this study, this concept was used to assess the health situation of 139 women living in eight quilombola communities located in a mining area, on the banks of the Trombetas River, in Oriximiná, Pará, Brazil. Data were collected by semi-structured individual interviews, which underwent quantitative analysis and descriptive statistics. Although quilombola communities are historically vulnerable, women are further weakened by individual, social, and programmatic factors, revealed in the poor access to education, information, work, income and health. Hence, public policies specifically suited to their gender and socio-cultural profile are needed.

Fish tissues for biomonitoring toxic and essential trace elements in the Lower Amazon

Brazilian soils can have high concentrations of toxic elements, mainly mercury (Hg) and arsenic (As), metals also associated with anthropogenic activities (e.g. intensive agriculture, mining, deforestation and hydroelectric plants). This can lead to large amounts of these elements reaching and/or being mobilized in the aquatic ecosystem, which constitutes a serious threat to the environment and to the health of local populations. Thus, we evaluate the feasibility of analyzing the tissues of freshwater fish species for monitoring toxic and trace element accumulation within the aquatic ecosystem in the Lower Amazon, Brazil. Two fish species were considered: Cichla temensis (Tucunaré), a carnivorous species, and Pterygoplichthys pardalis (Acari), a detritivorous species. Samples of liver and muscle from both species were evaluated in relation to their potential use for biomonitoring purposes. The study findings clearly demonstrate the value these fish species and tissues, particularly liver, for biomonitoring toxic and trace element concentrations in the aquatic environment across the study region. While Tucunaré liver proved the best option for biomonitoring elements that accumulate through the food chain (e.g. Hg), Acari liver better reflected elements that typically accumulate in the sediments (e.g. As). Moreover, the trace element profiles, determined using chemometric (multivariate) techniques, differed greatly in specimens from waters in the Andean mountain range (sampling sites located in the main course of the Amazon River) with high sediment concentrations, and in specimens from the Guyana and Brazilian shields (Porto Trombetas on the Trombetas River and Itaituba on the Tapajós River). The findings also indicate that deposition of elements in freshwater fish in this area is mainly associated with the geological origin of the soils and that large amounts of toxic elements can reach the aquatic ecosystem due to anthropogenic activities, thereby posing a serious danger to the environment and the health of the riverside communities.

Growth and survival over ten years of Brazil-nut trees planted in three anthropogenic habitats in northern Amazonia

ABSTRACT We examined the growth and survival of Brazil-nut trees, Bertholletia excelsa (Lecythidaceae) under different environmental conditions and levels of canopy openness within experimental plantations in the Trombetas River valley, in northern Brazil. We planted 144 seedlings in three anthropogenic habitats with different levels of sunlight exposition: crop field (100% canopy opening), shrub fallow (20-80% canopy opening) and Brazil-nut forest (< 10% canopy opening). We measured plant height and diameter annually and recorded mortality and resprouting over ten years. The performance of B. excelsa differed significantly among habitats, with the highest growth rate observed at the highest level of canopy openness (crop field). Survival was highest in crop field (85%) and shrub fallow (63%) and lowest in Brazil-nut forest (17%). Resprouting capacity was higher in the crop field, as Brazil-nut plants recovered after fire episodes, with most plants resprouting more than one shoot. Some trees in the crop field began to produce flowers and fruits at 9-10 years. We showed that B. excelsa juveniles are light-demanding, with higher survival and growth under conditions of high light exposure. We suggest the use of Brazil-nut trees for reforestation, restoration of degraded lands and enrichment of secondary vegetation, as long as an adequate management is adopted (e.g., maintaining plants exposed to direct sunlight and control of competing pioneer species).

The importance of understanding local legends to conserve wildlife: freshwater turtles of the Amazon

The purpose of this paper is to reveal for the first time some of the legends that have been told about turtles from generation to generation in the quilombola communities in the Rio Trombetas. Fro...

A new species of Microcharacidium (Characiformes: Crenuchidae) from the Central Amazon, Brazil

A new species (Microcharacidium bombioides sp. nov.) of the genus Microcharacidium Buckup, 1993 is described from the Rio Negro, Rio Trombetas, Rio Tapajós, tributaries of the Rio Madeira, and the middle Rio Amazonas. The new species is promptly distinguished from all congeners (Microcharacidium eleotrioides (Géry, 1960), Microcharacidium gnomus Buckup, 1993, and Microcharacidium weitzmani Buckup, 1993) by the presence of 12 circumpeduncular scales, 19 precaudal vertebrae, and 7 dark bars on the flanks connected to their contralateral parts both dorsally and ventrally; 2 short, dark suborbital stripes; all teeth on both jaws conical; 10–11 total dorsal-fin rays; and 3–4 perforated lateral line scales. An updated identification key for the genus is provided and the affinities of the new species with other Microcharacidium are discussed.

Taxonomic study of Moenkhausia cotinho Eigenmann, 1908 and Hemigrammus newboldi (Fernández-Yépez, 1949) with the description of two new speciesof Moenkhausia (Teleostei: Characiformes: Characidae).

Moenkhausia cotinho is redescribed based on the examination of meristic and morphometric data and external morphological characters of specimens from the Amazon and Orinoco basins and from rivers in the Guyana. The species is distinguished from congeners based on the combination of a reticulate color pattern, the presence of dark spots on the posterior edge of scales of the longitudinal rows dorsal to the lateral line, the presence of a dark blotch on the caudal-fin base failing to reach the posterior tip of the middle caudal-fin rays; the dorsal region of the eyes red to orange in life; 5/3 longitudinal series of scales, above and below the lateral line, respectively; and the tips of the pectoral-fin rays not extending beyond the base of the pelvic fin. All specimens of M. cotinho have a completely pored literal line except for a few specimens from drainages in the Guyana. The redefinition of the taxonomic limits and geographic distribution of M. cotinho allowed us to reevaluate the taxonomic limits and geographic distribution of Hemigrammus newboldi, the identity of which has been previously questioned, but which is clearly diagnosed from M. cotinho based on the relatively longer pectoral fin, the presence of conical teeth in the posterior portion of the dentary, the absence of a reticulate color pattern of body and in the shorter longitudinal dark stripe on body. In addition, two new species of Moenkhausia are described: Moenkhausia rondoni sp n. from the rio Madeira basin, Brazil and Moenkhausia pirahan sp n. from the lower rio Madeira and rio Trombetas and rio Tapajós basins, Brazil.

A New Hyphessobrycon (Characiformes: Characidae) from the Guiana Shield in Northern Brazil

A new species of Hyphessobrycon from a tributary of the Rio Paru do Oeste (Rio Trombetas basin), at the lower Amazon basin draining the Guiana Shield region in Para State, Brazil, is described. The new species presents a unique combination of an irregularly-shaped humeral blotch, a broad diffuse midlateral stripe, and a roughly triangular caudal peduncle blotch. The new species is herein included in the Hyphessobrycon agulha species-group, and comparisons with species belonging to this group and to a similar-looking non-congener, Hemigrammus bellottii, are presented.

Peltogyne barbata (Leguminosae, Detarioideae), a new species endemic to the Trombetas River area, Brazil

SummaryPeltogyne barbata (Leguminosae, Detarioideae), a new species endemic to lake margins and the banks of the Trombetas River in the state of Pará, northern Brazil, is described and illustrated. The new species is morphologically similar to P. densiflora Spruce ex Benth. in fruit shape and flower morphology, and both species occur in flooded areas (igapó). Peltogyne barbata can be distinguished by its partially tomentose ovary, the coloration of its adaxial sepals, and for having leaves present near the inflorescences pre-anthesis but branches without leaves post-anthesis. We provide an identification key to the species of the genus Peltogyne that occur in the Trombetas River region, as well as a line drawing, a distribution map and colour photographs of the new species in its native environment.

A new Amazonian species of Brachychalcinus (Characiformes: Characidae) from the Trombetas River basin, Brazil.

A new species of Brachychalcinus is described from the Rio Trombetas basin, Brazil. It differs from congeners by possessing a conspicuous rounded second humeral spot. Additionally, our new species differs from Brachychalcinus nummus, B. orbicularis and B. reisi by having a higher number of branched dorsal-fin rays, and from Brachychalcinus parnaibae by having a lower head depth.

Species richness and composition of snake assemblages in poorly accessible areas in the Brazilian Amazonia

Abstract: Snakes are a diverse group of terrestrial vertebrates of the order Squamata. Despite that, in the Amazonian biome, information about distribution and identification of snakes is limited when compared to other groups. Additionally, in Amazonia there is a sampling bias towards areas geographically close to urban centers and more densely populated areas. This in turn leads to false distribution gaps in poorly accessible areas of Amazonia. In this article we report the composition of snake assemblages in six areas of the Brazilian Amazonia, based on field sampling conducted over four years using standardized methods. We sampled 70 species from eight families: Typhlopidae (n=1), Leptotyphlopidae (n=1), Anillidae (n=1), Boidae (n=5), Colubridae (n=15), Dipsadidae (n=35), Elapidae (n=7), and Viperidae (n=5). The largest number of species was recorded in the Trombetas River area and the lowest in the Jatapu River area. The total beta diversity was 0.40 and the snake assemblages were structured mainly by replacement (72.5%). The time-limited search was the method that recorded the greatest number of individuals in the studied areas (44.1%) and also the greatest number of species (n=40). However, some species were recorded only by other methods such as interception by pitfall traps with directional fences. Despite the large number of species sampled in the study, no particular area comprised more than 40% of species registered in all the areas, indicating that snakes are poorly detected even with large sampling effort across multiple areas of a species distribution.

The rise of Cynometra (Leguminosae) and the fall of Maniltoa: a generic re-circumscription and the addition of 4 new species.

Cynometra L. is a genus of ca. 85 species of shrubs to large trees. It is amongst the largest genera in the legume subfamily Detarioideae and one of the few with a pantropical distribution. Perhaps due to this wide distribution and high diversity, systematists and taxonomists have struggled with the classification of Cynometra and its close ally, the genus Maniltoa Scheff. Recent phylogenetic studies have shown that many of the African species are more closely related to other genera and that the genus Maniltoa is nested within a clade of Indo-Pacific Cynometra. Here, I present an emended circumscription of Cynometra that excludes the African species defined by jointed pedicels and dehiscent fruits and includes the species formerly recognised in Maniltoa. New combinations in Cynometra are also provided for those species that require them. Additionally, four new species of Neotropical Cynometra are described and illustrated: Cynometracerebriformissp. nov. from the lower Rio Trombetas in Brazil; Cynometradwyeriisp. nov. from the Darien gap region of Panama; C.tumbesianasp. nov. from the dry tropical forests of Ecuador and Peru; and C.steyermarkiisp. nov. from the foothills of the western Cordillera de la Costa in Venezuela.

Home Range of Yellow-Spotted Amazon River Turtles (Podocnemis unifilis) (Testudines: Podocnemididae) in the Trombetas River Biological Reserve, Pará, Brazil

Adult Podocnemis unifilis were monitored using VHF radio tracking from September 2013 to September 2014 in the Rio Trombetas Biological Reserve, Para, Brazil. Our aim was to analyze the use of space by this species near the nesting beach base by describing size and overlap of estimated home ranges. Transmitters were attached to 10 males and 10 females. The mean home range size calculated through the fixed-kernel (FK) method with 95% of the fixes was 79.28 ± 77.08 ha (0.56–215.07 ha; n = 13). The mean of overlapping areas was 14% with FK95% (0.02%–81%; n = 13) and 5% with FK50% (0.1%–23%; n = 9). There was a significant difference in the mean overlapping areas between females and males. The analysis of the overlap of activity centers estimated by FK50% is extremely important for the establishment of conservation strategies in the management plan for this species in the reserve. We were able to identify 2 critical areas for the maintenance of this population where there was a frequent overlap of activity centers: the first, identified during the dry season, was composed of small overlaps among 7 turtles and was near the nesting areas on the clay banks within the Lago Jacare; the second, identified during the rainy season, was composed of a concentration of overlap areas of larger size among 6 turtles and was an open area in the flooded forest. It is important not only to protect the nesting areas during the dry season but also to protect flooded forest areas with the major intensity of use along with the canals that link the flooded forests to the lakes in the rainy season. For conservation purposes, it is necessary to continue the protection of the nesting beaches throughout the savannas inside the lake where the species nests in the dry season. The flooded forest areas that are zones of intense use during the rainy season, and the canals where the turtles can move between lakes must be protected throughout the year.

Parotocinclus yaka, a new species of armored catfish (Loricariidae: Hypoptopomatinae), from the Amazon basin in Brazil.

Parotocinclus yaka is described as a new species of hypoptopomatine cascudinho from tributaries of the Rio Tiquié, tributary to the Rio Uaupés, upper Rio Negro drainage, Amazon basin, Amazonas State, Brazil. The new species is distinguished from its congeners in northeastern and southeastern Brazil by having the cheek canal plate elongated posteriorly on the ventral surface of the head and in contact with the cleithrum. Parotocinclus yaka is diagnosed from the Parotocinclus species of the Amazon, Orinoco and Guianas watersheds by having a conspicuous dark spots smaller than the pupil diameter distributed dorsally and laterally on the head; it is also differentiated from P. polyochrus (Casiquiare, Venezuela), P. longirostris (Rio Amazonas, Brazil), and P. eppleyi (Río Orinoco) by the absence of a Y-shaped light mark dorsally on the head. In addition, the absence of premaxillary and dentary accessory teeth and the presence of a Y-shaped spot on the snout distinguish the new species from P. collinsae (Essequibo River, Guyana), P. halbothi (Rio Trombetas, Brazil and Marowijne River, Suriname) and P. variola (Río Amazonas, Colombia). Parotocinclus yaka also differs from P. amazonensis (lower Amazon basin), P. aripuanensis (lower Amazon basin), P. britskii (Guyana, Suriname, eastern Venezuela, and Amapá State, Brazil), and P. dani (Rio Tapajós basin), by having more numerous oral teeth. The new species described herein is part of the group of small cascudinhos usually associated with marginal or submerged vegetation and submerged logs, of moderate current and clear transparency, found in conserved habitats in streams of the Amazon, Orinoco and Guianas rivers.

Desobediência Epistêmica e (Des)Colonização do imaginário no “Mito da Capela de Ouro”

A Igreja Católica, ao propagar a fé cristã e a conversão das populações indígenas e ribeirinhas da região amazônica, (re)produziu suas ideologias na forma de escritos, as quais também estão presentes nas narrativas orais. Neste artigo, cujo aporte teórico está vinculado aos estudos Pós-coloniais e ao pensamento Decolonial, a partir da articulação das diferenças entre o real e o imaginário, salvação e pecado, deseja-se responder a seguinte questão: a que formação ideológica e formas de educar estaria ligado o “Mito da Capela de Ouro”, na região do médio amazonas paraense? Para tanto, nesta pesquisa baseada em fontes bibliográficas e documentais, foram investigados diários de viagens de missionários à região Amazônica, especialmente à região do rio Trombetas, impressos e manuscritos publicados por igrejas e pelo Conselho Nacional de Proteção ao índio (CNPI), no século XX. Os dados apontam que o “Mito da Capela de Ouro” decorre de uma tentativa de colonização do imaginário das populações nativas da região, tendo em vista que o mundo sobrenatural cristão era inteiramente oposto ao mundo sobrenatural indígena e ribeirinho, relacionado naquele contexto à demonização.