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1.
Front Microbiol ; 15: 1352792, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38827154

RESUMO

Introduction: The microbial-induced restoration of ferruginous crusts (canga), which partially cover iron deposits and host unique ecosystems, is a promising alternative for reducing the environmental impacts of the iron mining industry. Methods: To investigate the potential of microbial action to accelerate the reduction and oxidation of iron in substrates rich in hematite and goethite, four different microbial treatments (water only as a control - W; culture medium only - MO; medium + microbial consortium - MI; medium + microbial consortium + soluble iron - MIC) were periodically applied to induce iron dissolution and subsequent precipitation. Except for W, all the treatments resulted in the formation of biocemented blocks. Results: MO and MI treatments resulted in significant goethite dissolution, followed by precipitation of iron oxyhydroxides and an iron sulfate phase, due to iron oxidation, in addition to the preservation of microfossils. In the MIC treatment, biofilms were identified, but with few mineralogical changes in the iron-rich particles, indicating less iron cycling compared to the MO or MI treatment. Regarding microbial diversity, iron-reducing families, such as Enterobacteriaceae, were found in all microbially treated substrates. Discussion: However, the presence of Bacillaceae indicates the importance of fermentative bacteria in accelerating the dissolution of iron minerals. The acceleration of iron cycling was also promoted by microorganisms that couple nitrate reduction with Fe(II) oxidation. These findings demonstrate a sustainable and streamlined opportunity for restoration in mining areas.

2.
Environ Sci Pollut Res Int ; 31(17): 25424-25436, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38472582

RESUMO

Laboratory ecotoxicological tests are important tools for the management of environmental changes derived from anthropogenic activities. Folsomia candida is usually the model species used in some procedures. However, this species may not be sufficiently representative of the sensitivity of the other collembolan species. This study aimed to evaluate (i) the effects of soils naturally rich in potentially toxic elements (PTE) and soil characteristics on the reproduction and survival of different collembolan species, (ii) whether the habitat function of these soils is compromised, and (iii) to what extent F. candida is representative of the other collembolan species. For this, reproduction tests with six collembolan species were conducted in 14 different samples of soils. In general, collembolan reproduction was not completely inhibited in none of the natural tested soils. Even soils with high pollution load index values did not negatively affect collembolan reproduction for most of the species. In contrast, the lowest collembolan reproduction rates were found in a visually dense soil (lowest volume/weight ratio), highlighting that soil attributes other than total PTE concentration also interfere in the reproduction of collembolans. Our results support the idea that the F. candida species might not be representative of other collembolan species and that laboratory tests to assess soil contaminations should be conducted using diverse collembolan species.


Assuntos
Artrópodes , Poluentes do Solo , Animais , Solo , Poluentes do Solo/análise , Poluição Ambiental , Reprodução
3.
Plants (Basel) ; 12(12)2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37375882

RESUMO

Serra dos Carajás harbors a unique open plant community in Amazonia, known as canga vegetation, with several endemic species coexisting with the potential threat of large-scale iron ore mining. In this sense, Convolvulaceae occur in a wide variety of canga geoenvironments with multiple flower visitors, but the scarcity of data on its pollen morphology prevents the correct association between Convolvulaceae species with floral visitors, as well as the precise identification of their habitats throughout the Quaternary. Therefore, this study aims to contribute to the taxonomic knowledge and refinement of the identification of insect-plant networks of endangered plants, including Ipomoea cavalcantei. Pollen grains were examined by light and scanning electron microscopy (LM and SEM, respectively), and the morphological parameters obtained were statistically analyzed using principal component analysis. Therefore, all species were differentiated based on aperture types and exine ornamentation. The set of morphological characters indicated that echinae morphology, easily identified under LM, was effective for the identification of Ipomoea species. This work represents the first robust pollen database for a precise identification at the species level of Convolvulaceae from southeastern Amazonian cangas.

4.
Environ Pollut ; 329: 121595, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37059169

RESUMO

The expansion of areas of human occupation and the increase in economic activity and deforestation are negatively impacting the Amazon ecosystem. Situated in the Carajás Mineral Province in the southeastern Amazon, the Itacaiúnas River Watershed (IRW) encompasses several active mines and has a historical record of intense deforestation primarily linked with the expansion of pasturelands, but also of urban areas, and mining activities. Industrial mining projects are subjected to strict environmental control, but artisanal mining (ASM; 'garimpos') sites have not been controlled, despite their known environmental impacts. In recent years, the opening and expansion of ASM in the IRW for the exploitation of mineral resources (Au, Mn, and Cu) have been remarkable. This study presents evidence of anthropogenic impacts, mainly caused by ASM, on the quality and hydrogeochemical characteristics of the IRW surface water. The hydrogeochemical data sets of two projects carried out in the IRW, during 2017 and from 2020 until present, were used to evaluate these impacts within the region. Water quality indices were calculated for the surface water samples. For the whole IRW, water collected during the dry season tended to yield better quality indicators in comparison to those collected during the rainy season. Two sampling sites at Sereno Creek showed very poor water quality and extremely high concentrations of Fe, Al, and potentially toxic elements over time. From 2016 to 2022, ASM sites increased markedly. Moreover, there are indications that Mn exploitation via ASM in Sereno hill is the main source of contamination in the area. New trends of ASM expansion were observed along the main watercourses, related to the exploitation of Au from alluvial deposits. Similar anthropogenic impacts are registered in other regions of the Amazon and environmental monitoring should be encouraged to assess the chemical safety of strategic areas.


Assuntos
Poluentes Químicos da Água , Qualidade da Água , Humanos , Ecossistema , Monitoramento Ambiental , Rios , Minerais , Poluentes Químicos da Água/análise
5.
Microorganisms ; 11(2)2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36838412

RESUMO

Lateritic duricrusts cover iron ore deposits and form spatially restricted, unique canga ecosystems endangered by mining. Iron cycling, i.e., the dissolution and subsequent precipitation of iron, is able to restitute canga duricrusts, generating new habitats for endangered biota in post-mining landscapes. As iron-reducing bacteria can accelerate this iron cycling, we aim to retrieve microbial enrichment cultures suitable to mediate the large-scale restoration of cangas. For that, we collected water and sediment samples from the Carajás National Forest and cultivated the iron-reducing microorganisms therein using a specific medium. We measured the potential to reduce iron using ferrozine assays, growth rate and metabolic activity. Six out of seven enrichment cultures effectively reduced iron, showing that different environments harbor iron-reducing bacteria. The most promising enrichment cultures were obtained from environments with repeated flooding and drying cycles, i.e., periodically inundated grasslands and a plateau of an iron mining waste pile characterized by frequent soaking. Selected enrichment cultures contained iron-reducing and fermenting bacteria, such as Serratia and Enterobacter. We found higher iron-reducing potential in enrichment cultures with a higher cell density and microorganism diversity. The obtained enrichment cultures should be tested for canga restoration to generate benefits for biodiversity and contribute to more sustainable iron mining in the region.

6.
Environ Res ; 232: 115107, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36702190

RESUMO

This study presents the first integrated study on total Hg (THg) level in surface soil (SS), bottom soil (BS), stream sediments (SD), lake sediments (LS), stream water (SW), and lake water (LW) of Itacaiúnas River Watershed (IRW), Brazil to investigate the source and distribution of Hg in different environmental media considering contrasts of geological domains and sub-basins and its potential ecological and human risk. Hg content in most of the soils and sediments were above the upper crustal average values (56 µg/kg), however, when compared to the legal limits set by the Resolution CONAMA (Conselho Nacional de Meio Ambiente: soil 500 µg/kg; sediment 486 µg/kg), only 1 soil sample from Parauapebas sub-basin and 4 sediment samples from Violão Lake exceeded the limit. None of the SW and LW samples (<0.2 µg/L; CONAMA limit for Class II freshwater) are markedly contaminated by Hg. The SS and BS show similar contents and spatial distribution of Hg with higher contents being registered mostly in the Itacaiúnas and Parauapebas sub-basins, which are closely correlated with SD. This suggests that Hg levels are largely of geogenic origin and anthropogenic effect is highly limited. Principal Component Analysis (PCA) results show that Hg is strongly associated with total organic carbon (TOC), loss on ignition (LOI), and SO3, indicating organic matter as the main factor controlling the distribution of Hg and this is the major cause of accentuated Hg enrichment in lake sediments. The ecological risk index revealed a low pollution risk for most of the solid samples, except 11% LS and <1.5% SS and SD samples, which registered moderate risk. Health risk assessment indicated no adverse non-carcinogenic health effect on either adults and children in terms of Hg contamination. This information will be useful for Hg risk assessment in the Carajás region and future environmental research in this direction in the Amazonia.


Assuntos
Mercúrio , Poluentes Químicos da Água , Criança , Humanos , Mercúrio/análise , Brasil , Multimídia , Solo , Medição de Risco , Rios , Água , Monitoramento Ambiental/métodos , Sedimentos Geológicos , Poluentes Químicos da Água/análise , China
7.
Environ Manage ; 71(2): 483-493, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36459196

RESUMO

The application of the mitigation hierarchy (MH) to mining projects is challenging in situations of locational overlap between endemic flora and mineral deposits. We review flora surveys conducted in connection with the environmental impact assessment of several iron ore mining projects in an area of high degree of endemism in Eastern Amazon to discuss the practical implications of anticipating conservation strategies. Desktop studies and secondary data review were conducted to guide field searches to determine the distribution of endemic flora, resulting in 45 out of 46 endemic plant species having their known distribution extended to new areas. A framework for positioning flora conservation strategies in the MH is presented. Specific habitat requirements and scarce knowledge about endangered and endemic flora species are a conservation obstacle, since essential information to define species conservation strategies may be lacking. We show that anticipating conservation strategies can minimize time-lag uncertainties related to restoration success and biodiversity offsets. The more effort is placed in the preventative steps of the MH, the smaller the time-lag between impact (biodiversity losses) and conservation outcomes (biodiversity gains), decreasing uncertainties and reducing risks to biodiversity.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Conservação dos Recursos Naturais/métodos , Biodiversidade , Mineração
8.
Zoosystema ; 45(16): 463-498, 2023.
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-5133

RESUMO

Here we describe the new species Pseudoporatia kananciue Iniesta, Bouzan, Souza & Brescovit, n. sp., widespread in the Amazonian ferruginous landscape of the state of Pará, Brazil. The species differs from its only congener P. perplexa Golovatch, 1999 by the presence of 19 body rings in adults (vs 20 body rings), the position of the porosteles on the paraterga, and the morphology of the gonopods. Notes on its ecology and comments on the diversity of millipedes in the region of Serra dos Carajás, state of Pará, Brazil, are also provided. Ajouts à la faune de mille-pattes d'un paysage ferrugineux amazonien: une nouvelle espèce de Pseudoporatia Golovatch, 1999 répandue dans les affleurements rocheux (Diplopoda, Polydesmida, Pyrgodesmidae). Nous décrivons ici la nouvelle espèce Pseudoporatia kananciue Iniesta, Bouzan, Souza & Brescovit, n. sp., répandue dans le paysage ferrugineux amazonien de l'État de Pará, Brésil. L'espèce diffère de son seul congénère P. perplexa Golovatch, 1999 par la présence de 19 anneaux corporels chez les adultes (contre 20 anneaux corporels), la position des porostèles sur les paraterga et la morphologie des gonopodes. Des notes sur son écologie et des commentaires sur la diversité des mille-pattes dans la région de Serra dos Carajás, État de Pará, Brésil, sont également fournis.

9.
Environ Res ; 211: 113090, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35278468

RESUMO

Artisanal gold (Au) mining may have increased the concentrations of rare earth elements (REEs) in the Serra Pelada mine (southeastern Amazon, Brazil), which has not been evaluated so far. The objectives of this study were to determine the concentrations of cerium (Ce), lanthanum (La), scandium (Sc), and yttrium (Y) in the surroundings of the Serra Pelada mine, as well as the environmental risks associated with these elements. Therefore, 27 samples were collected in agricultural, forest, mining, and urban areas, and submitted to chemical and particle size characterization. The concentrations of REEs were quantified by inductively coupled plasma mass spectrometry (ICP-MS) and used to estimate pollution indices and environmental risks of the studied elements. All REEs had higher levels in the anthropized areas when compared to the forest area, except Sc in the mining and urban areas. Pollution load indices revealed that all areas are contaminated (>1) by the combined effect of REEs, especially the agricultural areas (index of 2.3). The element of greatest enrichment in the studied areas was Y, with enrichment factors of 18.2, 39.0, and 44.4 in the urban, agriculture, and mining areas, respectively. However, the potential ecological risk indices were low (<150) in all areas, indicating that there are no current environmental risks by the studied REEs.


Assuntos
Ouro , Metais Terras Raras , Monitoramento Ambiental/métodos , Poluição Ambiental/análise , Ouro/análise , Metais Terras Raras/análise , Mineração
10.
J Hazard Mater ; 421: 126688, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34315634

RESUMO

Improper disposal of copper mining wastes can threaten the ecosystem and human health due to the high levels of potentially toxic elements released into the environment. The objective of this study was to determine the properties of Cu mining wastes generated in the eastern Amazon and their potential risks to environment and human health. Samples of forest soil and artisanal/industrial Cu mining wastes were collected and subjected to characterization of properties and pseudo-total concentrations of Al, As, Ba, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, and Zn, in addition to chemical fractionation of Cu. The pH ranged from near neutrality to alkaline. Pseudo-total concentrations of Cu were high in all wastes, mainly in the artisanal rock waste, with 19,034 mg kg-1, of which 61% is concentrated in the most reactive fractions. Pollution indices indicated that the wastes are highly contaminated by Cu and moderately contaminated by Cr and Ni. However, only the artisanal rock waste is associated with environmental risk. Non-carcinogenic and carcinogenic human health risks were detected, especially from exposure to Cr in the artisanal rock waste. Prevention actions and monitoring of the artisanal mining area are necessary to avoid impacts to the local population.


Assuntos
Metais Pesados , Poluentes do Solo , Cobre/toxicidade , Ecossistema , Monitoramento Ambiental , Humanos , Resíduos Industriais/análise , Metais Pesados/análise , Mineração , Medição de Risco , Poluentes do Solo/análise
11.
Environ Res ; 204(Pt B): 112024, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34516979

RESUMO

Anthropogenic activities may have increased the concentrations of potentially toxic elements (PTEs) in fish from the southeastern Carajás Mineral Province in Brazil, which has not yet been studied. The objectives were to determine the quality parameters of surface water and bottom sediments, and to assess the bioaccumulation and risks of Al, Fe, Ba, Cd, Co, Cr, Cu, Mn, Mo, Ni, Pb, Ti, V and Zn in fish species from the southeastern Carajás Mineral Province. Water, sediments and fish species (Colossoma macropomum, Curimata cyprinoides, Geophagus sp., Leporinus trifasciatus, and Serrasalmus eigenmanni) were collected in 14 areas in the municipalities of Parauapebas, Marabá and Canaã dos Carajás, contemplating the Gelado Stream and the Parauapebas, Tapirapé and Itacaiúnas Rivers. Water samples were subjected to physicochemical analysis using a multiparameter meter. Concentrations of PTEs in all samples were quantified by inductively coupled plasma-optical emission spectrometry. Enrichment factor (EF) and geoaccumulation index (Igeo) were calculated to study the sediment enrichment and contamination. Ecological and human health risk assessments were performed to determine the risks to the environment and population's health. EF and Igeo revealed that the sediments from the Parauapebas River and Gelado Stream are respectively enriched by Ba, Co, Cu, Cr, Mn, Pb, and Ba, Co, Cr, Ni, Pb and V. The concentrations of Fe (1.67 mg L-1) and Mn (0.11 mg L-1) in water and the concentrations of Cr (>0.1 mg kg-1) and Pb (>2 mg kg-1) in fish were above the Brazilian legislation thresholds. The ecological risk assessment revealed considerable risk from Ni and moderate risk from multiple PTEs in sediments from the Gelado Stream. Human health risks were detected for Pb in all fish species and for Mo in L.trifasciatus. These results indicate that techniques for monitoring and controlling contamination must be implemented by the environmental agencies.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Animais , Efeitos Antropogênicos , Bioacumulação , Brasil , Monitoramento Ambiental , Sedimentos Geológicos , Humanos , Metais Pesados/análise , Minerais , Medição de Risco , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
12.
Taxonomy, v. 2, n. 2, p. 244-254, jun. 2022
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-4394

RESUMO

Parabatinga danielae sp. n. is described and illustrated based on material collected in caves of the Carajás region, state of Pará, Brazilian Amazonia. With the inclusion of the second species in the genus, we propose here a new diagnosis for Parabatinga and its type species, P. brevipes (Keyserling, 1891).

13.
Ecol Evol ; 11(19): 13348-13362, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34646474

RESUMO

The canga of the Serra dos Carajás, in Eastern Amazon, is home to a unique open plant community, harboring several endemic and rare species. Although a complete flora survey has been recently published, scarce to no genetic information is available for most plant species of the ironstone outcrops of the Serra dos Carajás. In this scenario, DNA barcoding appears as a fast and effective approach to assess the genetic diversity of the Serra dos Carajás flora, considering the growing need for robust biodiversity conservation planning in such an area with industrial mining activities. Thus, after testing eight different DNA barcode markers (matK, rbcL, rpoB, rpoC1, atpF-atpH, psbK-psbI, trnH-psbA, and ITS2), we chose rbcL and ITS2 as the most suitable markers for a broad application in the regional flora. Here we describe DNA barcodes for 1,130 specimens of 538 species, 323 genera, and 115 families of vascular plants from a highly diverse flora in the Amazon basin, with a total of 344 species being barcoded for the first time. In addition, we assessed the potential of using DNA metabarcoding of bulk samples for surveying plant diversity in the canga. Upon achieving the first comprehensive DNA barcoding effort directed to a complete flora in the Brazilian Amazon, we discuss the relevance of our results to guide future conservation measures in the Serra dos Carajás.

14.
Geobiology ; 19(4): 326-341, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33660904

RESUMO

Microbial activity is often invoked as a direct or indirect contributor to the precipitation of ancient chemical sedimentary rocks such as Precambrian iron formations (IFs). Determining a specific metabolic pathway from the geological record remains a challenge, however, due to a lack of constraints on the initial conditions and microbially induced redox reactions involved in the formation of iron oxides. Thus, there is ongoing debate concerning the role of photoferrotrophy, that is the process by which inorganic carbon is fixed into organic matter using light as an energy source and Fe(II) as an electron donor, in the deposition of IFs. Here, we examine ~2.74-Ga-old Neoarchean IFs and associated carbonates from the Carajás Mineral Province, Brazil, to reconstruct redox conditions and to infer the oxidizing mechanism that allowed one of the world's largest iron deposits to form. The absence of cerium (Ce) anomalies reveals that conditions were pervasively anoxic during IF deposition, while unprecedented europium (Eu) anomalies imply that Fe was supplied by intense hydrothermal activity. A positive and homogeneous Fe isotopic signal in space and time in these IFs indicates a low degree of partial oxidation of Fe(II), which, combined with the presence of 13 C-depleted organic matter, points to a photoautotrophic metabolic driver. Collectively, our results argue in favor of reducing conditions during IF deposition and suggest anoxygenic photosynthesis as the most plausible mechanism responsible for Fe oxidation in the Carajás Basin.


Assuntos
Ferro , Fotossíntese , Brasil , Carbonatos , Oxirredução
15.
Mitochondrial DNA B Resour ; 6(2): 415-417, 2021 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-33659697

RESUMO

Coleoptera presents most of the cave fauna biodiversity, with several troglobite species belonging to the aquatic family Dytiscidae. However, very little is known on both genetic and genomic diversity traits of Neotropical cave beetles. Thus, here we present the complete mitochondrial genome sequence of five specimens of Desmopachria collected in a ferruginous cave from Serra dos Carajás in Parauapebas (Pará, Brazil, Eastern Amazon). Besides the general characteristics of the mitogenome of the analyzed specimens, we present their phylogenetic position within the family, considering the available genome sequences of different subfamilies within Dytiscidae.

16.
Environ Manage ; 67(4): 698-716, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33439303

RESUMO

The ability of communities to react to risks and disturbances is for their balance, development, and sustainability. The concept of resilience provides a way to think about policies and actions for future changes in socioeconomic and ecological-environmental systems. This paper analyzes, in the context of mining, the perception of the resilience of Canaã dos Carajás population in Pará State, Brazilian Amazon. The methodology involved face-to-face interviews based on a structured questionnaire conducted on a sample of 140 residents stratified from 11 social actors in the Canaã community. This approach allowed the evaluation of resilience perception using 26 interview statements derived from six resilience theories. Our multivariate analysis found that the level of residents' perception of resilience was reasonable (with an average score of 3.04 ± 0.22 using a Likert scale, with a Cronbach's alpha of 0.788). The interviewees pointed out one positive and five negative factors that influenced the level of resilience in Canaã. According to residents' perceptions, the resilience of Canaã dos Carajás was moderate but could have been improved with more economic diversification, more infrastructure, and less inequality in access to services and participation in decision-making. The considered most relevant themes were problems caused by mining in the municipality, quality of life issues, difficulties dealing with change after the arrival of mining, and economic problems. This study contributes to the literature because it used theories as a conceptual orientation for the development of a resilience scale to measure resilience at the community level in the context of large-scale mining.


Assuntos
Mineração , Qualidade de Vida , Brasil , Ecossistema , Percepção
17.
Environ Entomol ; 49(6): 1374-1382, 2020 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-33015710

RESUMO

Most studies analyze fragmentation due to habitat loss caused by anthropogenic activities and few of them analyzed fragmentation on naturally fragmented areas. In the Eastern Amazon, it is possible to find areas naturally open and surrounded by pristine forest. Understanding how species respond to isolation in these areas is an important challenge for decision-making processes aiming conservation and restoration. Using standardized methods of bee collection (entomological nets, bait trap, pan trap, and nest trap), the objective of this study was to analyze the composition and diversity of bees occurring on six isolated outcrops located in two protected areas within Amazon biome. More specifically, we tested 1) if the dissimilarity in bee species composition is explained by the isolation of outcrops and 2) if bee richness, abundance, and Shannon diversity can be explained by the outcrop size. We found 118 species, with the Meliponini and Euglossini (Hymenoptera: Apidae) tribes representing the highest number of species. The similarity in species composition across all outcrops is high and is not explained by the isolation. In addition, the richness, abundance, and Shannon diversity are not explained by outcrop size. Forest does not seem to be a barrier to bee movement, and although most species probably nest in the forests, they use the highly diverse plants of the outcrops as a complementary food source.


Assuntos
Florestas , Himenópteros , Animais , Abelhas , Biodiversidade , Ecossistema , Plantas
18.
Front Plant Sci ; 11: 599496, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33424895

RESUMO

Cangas (ironstone outcrops) host a specialized flora, characterized by high degree of edaphic endemism and an apparent lack of natural history knowledge of its flora. Due to intense pressure from iron ore mining this ecosystem is under threat and in need of restoration. We studied seed functional traits that are relevant for restoration, translocation and ex situ conservation in 48 species from cangas in eastern Amazon. Were determined the thermal niche breadth, classified seed dormancy and determined methods to overcome it, determined the effect of seed storage on germination, tested the association between germination traits and functional groups, and tested whether seed traits are phylogenetically conserved. We found a broad interspecific variation in most seed traits, except for seed water content. Large interspecific variation in the temperature niche breadth was found among the studied species, but only four species, showed optimum germination at high temperatures of 35-40°C, despite high temperatures under natural conditions. Only 35% of the studied species produced dormant seeds. Mechanical scarification was effective in overcoming physical dormancy and application of gibberellic acid was effective in overcoming physiological dormancy in five species. For the 29 species that seeds were stored for 24 months, 76% showed decreases in the germination percentage. The weak association between germination traits and life-history traits indicate that no particular plant functional type requires specific methods for seed-based translocations. Exceptions were the lianas which showed relatively larger seeds compared to the other growth-forms. Dormancy was the only trait strongly related to phylogeny, suggesting that phylogenetic relatedness may not be a good predictor of regeneration from seeds in cangas. Our study provides support to better manage seed sourcing, use, storage and enhancement techniques with expected reduced costs and increased seedling establishment success.

19.
Mitochondrial DNA B Resour ; 5(3): 3272-3273, 2020 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-33458136

RESUMO

We report the complete mitochondrial genome sequence of Glomeridesmus spelaeus, the first sequenced genome of the order Gomeridesmida. The genome is 14,825 pb in length and encodes 37 mitochondrial (13 PCGs, 2 rRNA genes, 22 tRNA) genes and contains a typical AT-rich region. The base composition of the mitogenome was A (40.1%), T (36.4%), C (15.8%), and G (7.6%), with an GC content of 23.5%. Our results indicated that G. spelaeus is only distantly related to the other Diplopoda species with available mitochondrial genomes in the public databases. As the broadest genetic characterization of a Glomeridesmida species available to date, the mitogenome of G. spelaeus will help understanding the evolution of such a little-known millipede group. Also, our data will be important for the characterization and conservation of the diverse invertebrate troglofauna of the Amazonian caves.

20.
Zootaxa ; 4565(3): zootaxa.4565.3.8, 2019 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-31716468

RESUMO

Two new species of Helicopsychidae from Pará State, Brazil, are described and illustrated: male of Helicopsyche (Feropsyche) carajas n. sp. is characterized by segment X having 8 pairs of subequal megasetae distributed in a pair of longitudinal rows; the primary branch of each gonocoxite, in lateral view, with its basal half nearly as broad as its median part and parallel-sided, its posterior apex directed slightly ventrad and slender and strongly pointed; the dorsal lobes of the endotheca posteriorly protruding, and the lateral lobes of the endotheca well developed. Helicopsyche (Feropsyche) inflata n. sp. is characterized by the hind wings each having very long fringes along the anal border; the primary branch of each gonocoxite having a pointed apex in lateral view and its basimesal lobe being triangular in lateral and ventral views and bearing eight megasetae; and the dorsal lobe of the endotheca being very well developed in lateral view.


Assuntos
Holometábolos , Insetos , Animais , Brasil , Masculino
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