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1.
Bol. latinoam. Caribe plantas med. aromát ; 23(4): 645-683, jul. 2024. tab, ilus
Artículo en Inglés | LILACS | ID: biblio-1538073

RESUMEN

Information on the knowledge and ways of using food and medicinal plants by traditional populations, family farmers and Brazilian native population in the Amazon is essential to guarantee the food sovereignty of these groups. This study was conducted using semi-structured interviews applied to local respondents. A total of 269 species of both non-conventional food plants and medicinal plants were identified, distributed in 83 botanical families and 198 genera. The Arecaceae and Lamiaceae families had the highest species richness (11 and 7, respectively). The Shannon-Wiener (H') and Pielou (J') diversity indices were considered high (5.02 and 0.9, respectively) when compared to other ethnobotanical works. In the environment in which these families are found, these species become the only food and medicinal resources available.


La información sobre los saberes y formas de uso de las plantas alimenticias y medicinales por parte de las poblaciones tradicionales, agricultores familiares e indígenas brasileños en la Amazonía es fundamental para garantizar la soberanía alimentaria de estos grupos. Este estudio se realizó utilizando entrevistas semiestructuradas aplicadas a encuestados locales. Se identificaron un total de 269 especies tanto de plantas alimenticiasno convencionales como de plantas medicinales, distribuidas en 83 familias botánicas y 198 géneros. Las familias Arecaceae y Lamiaceae tuvieron la mayor riqueza de especies (11 y 7, respectivamente). Los índices de diversidad de Shannon-Wiener (H') y Pielou (J') fueron considerados altos (5,02 y 0,9, respectivamente) en comparación con otros trabajos etnobotánicos. En el ambiente en que se encuentran estas familias, estas especies se convierten en los únicos recursos alimenticios y medicinales disponibles.


Asunto(s)
Plantas Comestibles , Plantas Medicinales , Etnobotánica , Brasil , Encuestas y Cuestionarios
2.
Neotrop Entomol ; 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38656590

RESUMEN

Diverse abiotic and biotic factors drive the ecological variation of communities across spatial and temporal dimensions. Within the Amazonian landscape, various freshwater environments exhibit distinct physicochemical characteristics. Thus, our study delved into the fluctuations of Odonata assemblages amidst distinct water bodies within Amazonia, encompassing two distinct climatic seasons. Comparative analysis was conducted on Odonata species diversity and assemblage composition across a blackwater pond, a lake, and a stream, spanning the initiation and culmination of the dry season in the southwestern Amazon region in Peru. Our methodology involved capturing adult Odonata using entomological nets on three separate occasions between 11:00 and 14:00 h for each water body in May (beginning of the dry season) and October (end of the dry season) of 2018. We also evaluated the influence of temperature, precipitation, and percent cloud cover on the abundance and richness of adult Odonata. Species richness and composition differed among the three water bodies in both periods of the dry season. No effect of the dry season periods on species richness and abundance was observed. However, except in the oxbow lake, the more abundant species were substituted to the end of the dry season. Our study highlights the influence of water body types on Odonata species diversity and composition. The effects of the sampling period during the dry season may not be immediately apparent in conventional diversity metrics, such as species richness and abundance. Instead, its effects manifest predominantly in the relative abundance of the species that compose these assemblages.

3.
PLoS One ; 19(4): e0299954, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38635514

RESUMEN

For migratory birds, events happening during any period of their annual cycle can have strong carry-over effects on the subsequent periods. The strength of carry-over effects between non-breeding and breeding grounds can be shaped by the degree of migratory connectivity: whether or not individuals that breed together also migrate and/or spend the non-breeding season together. We assessed the annual cycle of the White-crested Elaenia (Elaenia albiceps chilensis), the longest-distance migrant flycatcher within South America, which breeds in Patagonia and spends the non-breeding season as far north as Amazonia. Using light-level geolocators, we tracked the annual movements of elaenias breeding on southern Patagonia and compared it with movements of elaenias breeding in northern Patagonia (1,365 km north) using Movebank Repository data. We found that elaenias breeding in southern Patagonia successively used two separate non-breeding regions while in their Brazilian non-breeding grounds, as already found for elaenias breeding in the northern Patagonia site. Elaenias breeding in both northern and southern Patagonia also showed high spread in their non-breeding grounds, high non-breeding overlap among individuals from both breeding sites, and similar migration phenology, all of which suggests weak migratory connectivity for this species. Elucidating the annual cycle of this species, with particular emphasis on females and juveniles, still requires further research across a wide expanse of South America. This information will be critical to understanding and possibly predicting this species' response to climate change and rapid land-use changes.


Asunto(s)
Passeriformes , Pájaros Cantores , Humanos , Animales , Femenino , Migración Animal/fisiología , Brasil , Cruzamiento , Estaciones del Año
4.
Ecol Evol ; 14(4): e11250, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38660467

RESUMEN

The "Amazon tipping point" is a global change scenario resulting in replacement of upland terra-firme forests by large-scale "savannization" of mostly southern and eastern Amazon. Reduced rainfall accompanying the Last Glacial Maximum (LGM) has been proposed to have acted as such a tipping point in the past, with the prediction that terra-firme inhabiting species should have experienced reductions in population size as drier habitats expanded. Here, we use whole-genomes of an Amazonian endemic organism (Scale-backed antbirds - Willisornis spp.) sampled from nine populations across the region to test this historical demography scenario. Populations from southeastern Amazonia and close to the Amazon-Cerrado ecotone exhibited a wide range of demographic patterns, while most of those from northern and western Amazonia experienced uniform expansions between 400 kya and 80-60 kya, with gradual declines toward 20 kya. Southeastern populations of Willisornis were the last to diversify and showed smaller heterozygosity and higher runs of homozygosity values than western and northern populations. These patterns support historical population declines throughout the Amazon that affected more strongly lineages in the southern and eastern areas, where historical "tipping point" conditions existed due to the widespread replacement of humid forest by drier and open vegetation during the LGM.

5.
PeerJ ; 12: e17232, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38646479

RESUMEN

The species richness in the Neotropics has been linked to environmental heterogeneity and a complex geological history. We evaluated which biogeographic processes were associated with the diversification of Monkey tree frogs, an endemic clade from the Neotropics. We tested two competing hypotheses: the diversification of Phyllomedusinae occurred either in a "south-north" or a "north-south" direction in the Neotropics. We also hypothesized that marine introgressions and Andean uplift had a crucial role in promoting their diversification. We used 13 molecular markers in a Bayesian analysis to infer phylogenetic relationships among 57 species of Phyllomedusinae and to estimate their divergence times. We estimated ancestral ranges based on 12 biogeographic units considering the landscape modifications of the Neotropical region. We found that the Phyllomedusinae hypothetical ancestor range was probably widespread throughout South America, from Western Amazon to Southern Atlantic Forest, at 29.5 Mya. The Phyllomedusines' ancestor must have initially diverged through vicariance, generally followed by jump-dispersals and sympatric speciation. Dispersal among areas occurred mostly from Western Amazonia towards Northern Andes and the South American diagonal of dry landscapes, a divergent pattern from both "south-north" and "north-south" diversification hypotheses. Our results revealed a complex diversification process of Monkey tree frogs, occurring simultaneously with the orogeny of Northern Andes and the South American marine introgressions in the last 30 million years.


Asunto(s)
Anuros , Teorema de Bayes , Filogenia , Animales , Anuros/genética , Anuros/clasificación , América del Sur , Filogeografía , Especiación Genética
6.
Artículo en Inglés | MEDLINE | ID: mdl-38573394

RESUMEN

PURPOSE: Over the past decade, the Amazon basin has faced numerous infectious epidemics. Our comprehension of the actual extent of these infections during pregnancy remains limited. This study aimed to clarify the clinical and epidemiological features of emerging and re-emerging infectious diseases during pregnancy in western French Guiana and along the Maroni River over the previous nine years. METHODS: This retrospective cohort study enrolled pregnant women living in west French Guiana territory and giving birth in the only local referral center after 22 weeks of gestation between 2013 and 2021. Data on symptomatic or asymptomatic biologically confirmed emerging or re-emerging diseases during pregnancy was collected. RESULTS: Six epidemic waves were experienced during the study period, including 498 confirmed Zika virus infections (2016), 363 SARS-CoV-2 infections (2020-2021), 87 chikungunya virus infections (2014), 76 syphilis infections (2013-2021), and 60 dengue virus infections (2013-2021) at different gestational ages. Furthermore, 1.1% (n = 287) and 1.4% (n = 350) of pregnant women in west French Guiana were living with HIV and HTLV, respectively. During the study period, at least 5.5% (n = 1,371) faced an emerging or re-emerging infection during pregnancy. CONCLUSION: These results highlight the diversity, abundance, and dynamism of emerging and re-emerging infectious agents faced by pregnant women in the Amazon basin. Considering the maternal and neonatal adverse outcomes associated with these infections, increased efforts are required to enhance diagnosis, reporting, and treatment of these conditions.

7.
Am J Primatol ; : e23625, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38558023

RESUMEN

Saimiri cassiquiarensis cassiquiarensis (Cebidae) is a primate subspecies with a wide distribution in the Amazonian region of Brazil, Colombia, and Venezuela. However, the boundaries of its geographic range remain poorly defined. This study presents new occurrence localities for this subspecies and updates its distribution using a compiled data set of 140 occurrence records based on literature, specimens vouchered in scientific collections, and new field data to produce model-based range maps. After cleaning our data set, we updated the subspecies' extent of occurrence, which was used in model calibration. We then modeled the subspecies' range using a maximum entropy algorithm (MaxEnt). The final model was adjusted using a fixed threshold, and we revised this polygon based on known geographic barriers and parapatric congeneric ranges. Our findings indicate that this subspecies is strongly associated with lowland areas, with consistently high daily temperatures. We propose modifications to all range boundaries and estimate that 3% of the area of occupancy (AOO, as defined by IUCN) has already been lost due to deforestation, resulting in a current range of 224,469 km2. We also found that 54% of their AOO is currently covered by protected areas (PAs). Based on these results, we consider that this subspecies is currently properly classified as Least Concern, because it occupies an extensive range, which is relatively well covered by PAs, and is currently experiencing low rates of deforestation.


Saimiri cassiquiarensis cassiquiarensis (Cebidae) é uma subespécie de primata com ampla distribuição na região amazônica do Brasil, Colômbia e Venezuela. No entanto, os limites de sua distribuição geográfica permanecem mal definidos. Este estudo apresenta novas localidades de ocorrência para essa subespécie e atualiza sua distribuição usando 140 registros de ocorrência compilados com base na literatura, espécimes depositados em coleções científicas e novos registros de campo para produzir mapas de distribuição baseados em modelos. Após a limpeza do nosso banco de dados, atualizamos a extensão de ocorrência da subespécie, que foi usada na calibração do modelo. Em seguida, modelamos a área de distribuição da subespécie usando um algoritmo de entropia máxima (MaxEnt). O modelo final foi ajustado usando um limiar fixo e revisamos esse polígono com base em barreiras geográficas conhecidas e na distribuição de congêneres parapátricas. Nosso modelo sugere que a espécie é fortemente associada a áreas planas, com temperaturas diárias consistentemente altas. Propomos modificações em todos os limites da área de distribuição e estimamos que 3% da área de ocupação (AOO, conforme definida pela IUCN) da subespécie já foi perdida devido ao desmatamento, resultando em uma área de distribuição atual de 224,469 km2. Também estimamos que 54% de sua AOO encontra­se atualmente coberta por áreas protegidas. Com base nesses resultados, consideramos que a subespécie está apropriadamente classificada como Pouco Preocupante, pois ocupa uma área extensa, que é relativamente bem coberta por áreas protegidas e atualmente apresenta baixas taxas de desmatamento.

8.
Am J Primatol ; : e23622, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38561573

RESUMEN

The consumption of primates is integral to the traditional subsistence strategies of many Indigenous communities throughout Amazonia. Understanding the overall health of primates harvested for food in the region is critical to Indigenous food security and thus, these communities are highly invested in long-term primate population health. Here, we describe the establishment of a surveillance comanagement program among the Waiwai, an Indigenous community in the Konashen Amerindian Protected Area (KAPA). To assess primate health in the KAPA, hunters performed field necropsies on primates harvested for food and tissues collected from these individuals were analyzed using histopathology. From 2015 to 2019, hunters conducted 127 necropsies across seven species of primates. Of this sample, 82 primates (between 2015 and 2017) were submitted for histopathological screening. Our histopathology data revealed that KAPA primates had little evidence of underlying disease. Of the tissue abnormalities observed, the majority were either due to diet (e.g., hepatocellular pigment), degenerative changes resulting from aging (e.g., interstitial nephritis, myocyte lipofusion), or nonspecific responses to antigenic stimulation (renal and splenic lymphoid hyperplasia). In our sample, 7.32% of individuals had abnormalities that were consistent with a viral etiology, including myocarditis and hepatitis. Internal parasites were observed in 53.66% of individuals and is consistent with what would be expected from a free-ranging primate population. This study represents the importance of baseline data for long-term monitoring of primate populations hunted for food. More broadly, this research begins to close a critical gap in zoonotic disease risk related to primate harvesting in Amazonia, while also demonstrating the benefits of partnering with Indigenous hunters and leveraging hunting practices in disease surveillance and primate population health assessment.

9.
Hepatol Commun ; 8(5)2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38619425

RESUMEN

BACKGROUND: The low prevalence of HDV infection in the United States could be attributed to insufficient testing rate, which can result in an underestimation of the true burden of HDV. The primary objective of this study is to quantify the prevalence of and factors associated with HDV antibody (anti-HDV) or RNA testing, among participants with positive HBsAg in the Veterans Health Administration (VHA). METHODS: We conducted a retrospective cohort study of participants who tested positive for HBsAg between January 2000 and December 2022 within the VHA. We identified those who were tested for HDV, and patient and provider-level factors associated with HDV testing. RESULTS: Of 41,658 participants with positive HBsAg who had follow-up, 4438 (10.7%) were tested at least once for HDV, of which 135 (3.0%) were positive. Participants in the Northeast (adjusted odds ratio [aOR]: 1.30, 95% CI: 1.17-1.44, p<0.001), and receiving hepatology care (aOR: 1.38, 95% CI: 1.24-1.54, p<0.001) were more likely, while those in the Midwest (aOR: 0.69, 95% CI: 0.60-0.79, p<0.001), under the care of a primary care provider (aOR: 0.61, 95% CI: 0.50-0.74, p<0.001), Blacks (aOR: 0.85, 95% CI: 0.77-0.94, p=0.001), participants who were HCV antibody-positive (aOR: 0.89, 95% CI: 0.81-0.99, p=0.03), and participants who were HIV-positive (aOR: 0.80, 95% CI: 0.71-0.90, p<0.001) were less likely to be tested for HDV. CONCLUSIONS: HDV screening rates in the VHA remain low overall. Participants who are Black, living in the Midwest, patients who are HIV-positive, and patients who are HCV-positive are less likely to be tested for HDV. These results suggest that risk-based screening strategies are ineffective in the VHA and highlight the need for refining testing strategies to increase HDV screening rates.


Asunto(s)
Infecciones por VIH , Hepatitis C , Hepatitis D , Humanos , Virus de la Hepatitis Delta/genética , Antígenos de Superficie de la Hepatitis B , Estudios Retrospectivos , Hepatitis D/diagnóstico , Hepatitis D/epidemiología , Hepatitis C/diagnóstico , Hepatitis C/epidemiología
10.
Nat Commun ; 15(1): 3158, 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38605006

RESUMEN

Tropical forests cover large areas of equatorial Africa and play a substantial role in the global carbon cycle. However, there has been a lack of biometric measurements to understand the forests' gross and net primary productivity (GPP, NPP) and their allocation. Here we present a detailed field assessment of the carbon budget of multiple forest sites in Africa, by monitoring 14 one-hectare plots along an aridity gradient in Ghana, West Africa. When compared with an equivalent aridity gradient in Amazonia, the studied West African forests generally had higher productivity and lower carbon use efficiency (CUE). The West African aridity gradient consistently shows the highest NPP, CUE, GPP, and autotrophic respiration at a medium-aridity site, Bobiri. Notably, NPP and GPP of the site are the highest yet reported anywhere for intact forests. Widely used data products substantially underestimate productivity when compared to biometric measurements in Amazonia and Africa. Our analysis suggests that the high productivity of the African forests is linked to their large GPP allocation to canopy and semi-deciduous characteristics.


Asunto(s)
Bosques , Árboles , Ciclo del Carbono , Ghana , Carbono , Ecosistema , Clima Tropical
11.
An Acad Bras Cienc ; 96(1): e20230659, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38655924

RESUMEN

Adelphobates contains three species, and the inaccurate identification of A. quinquevittatus and the scarcity of records of A. castaneoticus complicate inference of their distributions; the latter species occurs in sympatry with A. galactonotus. Our objective was to revise the distributions of Adelphobates by compiling data and modeling habitat suitability, as range limits may be shaped by landscape features and biotic interactions. We initially analyzed the existence of operational taxonomic units within the nominal species and subsequently inferred the observed and potential distributions, taking into account the possible independent lineages for the three species, and we also generated a molecular timetree to understand the chronology of interspecific diversification events. Adelphobates quinquevittatus was found to have a more easterly distribution than previously described, and specimens with phenotypic variation were found to occur in areas inconsistent with the modeling, and A. castaneoticus was concentrated in the Tapajós-Xingu interfluve, surrounded by A. galactonotus. Models indicated that the right bank of the Xingu River is suitable for both species, indeed, both were found there. Despite Adelphobates species having their distributions delimited by major Amazonian rivers, estimated divergence times predate the formation of the modern river network, suggesting that other mechanisms were involved in their diversification.


Asunto(s)
Anuros , Animales , Brasil , Anuros/clasificación , Anuros/genética , Distribución Animal , Ecosistema , Filogenia , Biodiversidad , 60633
12.
Ecology ; : e4272, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38590101

RESUMEN

Disturbances in tropical forests can have long-lasting ecological impacts, but their manifestations (ecological legacies) in modern forests are uncertain. Many Amazonian forests bear the mark of past soil modifications, species enrichments, and fire events, but the trajectories of ecological legacies from the pre-contact or post-colonial period remain relatively unexplored. We assessed the fire and vegetation history from 15 soil cores ranging from 0 to 10 km from a post-colonial Surinamese archaeological site. We show that (1) fires occurred from 96 bc to recent times and induced significant vegetation change, (2) persistent ecological legacies from pre-contact and post-colonial fire and deforestation practices were mainly within 1 km of the archaeological site, and (3) palm enrichment of Attalea, Oenocarpus and Astrocaryum occurred within 0, 1, and 8 km of the archaeological site, respectively. Our results challenge the notion of spatially extensive and persistent ecological legacies. Instead, our data indicate that the persistence and extent of ecological legacies are dependent on their timing, frequency, type, and intensity. Examining the mechanisms and manifestations of ecological legacies is crucial in assessing forest resilience and Indigenous and local land rights in the highly threatened Amazonian forests.

13.
An Acad Bras Cienc ; 96(1): e20230327, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38597490

RESUMEN

Aquatic macrophytes are the main autochthonous component of primary production in the Amazon Basin. Floating meadows of these plants support habitats with highly diverse animal communities. Fishes inhabiting these habitats have been assumed to use a broad range of food items and compose a particular food web. We employed carbon (δ13C) and nitrogen (δ15N) stable isotope analysis to draw the trophic structure of these habitats and to trace the energy flow by its trophic levels. Fishes and other animals from 18 independent macrophyte meadows of a floodplain lake of the Solimões River (Amazonia, Brazil) were analyzed. The food web of macrophyte meadows consists of four trophic levels above autotrophic sources. In general, primary consumers exhibited a broader range of food sources than the upper trophic levels. Some fish species depended on a large number of food sources and at the same time are consumed by several predators. The energy transfer from one trophic level to the next was then mainly accomplished by these species concentrating a high-energy flux and acting as hubs in the food web. The broad range of δ13C values observed indicates that the organisms living in the macrophyte meadows utilize a great diversity of autotrophic sources.


Asunto(s)
Pradera , Lagos , Animales , Lagos/química , Ecosistema , Cadena Alimentaria , Peces , Transferencia de Energía
14.
An Acad Bras Cienc ; 96(1): e20220413, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38597497

RESUMEN

This study aimed to analyze the application of the Phytoplankton Community Index-PCI and Functional Groups-FG in determining the water quality of the Guamá River (Pará, Amazônia, Brazil). Samplings occurred monthly for analyses of phytoplankton and physical and chemical parameters, for two years, at the station where water was collected for human supply consumption. Seasonality influenced electrical conductivity, total suspended solids, dissolved oxygen, transparency, winds, true color, and N-ammoniacal. The ebb tide showed high turbidity and suspended solids. The density varied seasonally with the highest values occurring in September and December (61.1 ind mL-1 and 60.2 ind mL-1, respectively). Chlorophyll-a was more elevated in December (21.0 ± 4.7 µg L-1) and chlorophyll-c higher in relation to clorophyll- b indicated the dominance of diatoms. Functional Group P prevailed in the study months. Through the PCI índex the waters of Guamá River varied from reasonable to excellent and the TSI ranged from oligo to mesotrophic. The use of Functional Groups proved to be a promising tool in the determination of water quality since it covered the most abundant species in the Environment, but the PCI is not adequate to characterize Amazonian white-waters rivers, which have diatoms as the leading dominant group.


Asunto(s)
Diatomeas , Intervención Coronaria Percutánea , Humanos , Fitoplancton , Ríos/química , Brasil , Clorofila/análisis , Estaciones del Año , Monitoreo del Ambiente
15.
An Acad Bras Cienc ; 96(suppl 1): e20230338, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38597502

RESUMEN

The family Hymenochaetaceae includes a diversity of 893 species described around the world. Its representatives are known by their usually rusty colored basidiomes with a poroid hymenial surface, hydnoid or smooth, woody consistency, and wide morphological variation regarding the arrangement on the substrate. They behave as saprophytic, parasitic, ectomycorrhizal and play a fundamental role in the decomposition of wood in forest ecosystems. In the Brazilian Amazonia region, approximately 40 species of Hymenochaetaceae are currently recorded. The main goal of this study was to increase the knowledge on Hymenochaetaceae from the Brazilian Amazonia. Collections were carried out between October 2021 and April 2022 in the state of Pará, municipalities of Tomé-Açu and Bujaru, to expanding the knowledge of this fungal family to the Brazilian Amazonia. A total of 15 specimens were identified, distributed in seven genera and 12 species. Four species are new records for the state of Pará (Fomitiporia apiahyna, Phellinus neocallimorphus, Phellinus sancti-georgii, and Sclerotus extensus) and two of them are new records for the Brazilian Amazonia (P. neocallimorphus and P. sancti-georgii). Our findings contribute to taxonomic knowledge of this family in the Brazilian Amazonia and reduce the information gaps about the diversity of species.


Asunto(s)
Basidiomycota , Ecosistema , Brasil , Ciudades , Bosques
16.
Biometrics ; 80(2)2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38591365

RESUMEN

A spatial sampling design determines where sample locations are placed in a study area so that population parameters can be estimated with relatively high precision. If the response variable has spatial trends, spatially balanced or well-spread designs give precise results for commonly used estimators. This article proposes a new method that draws well-spread samples over arbitrary auxiliary spaces and can be used for master sampling applications. All we require is a measure of the distance between population units. Numerical results show that the method generates well-spread samples and compares favorably with existing designs. We provide an example application using several auxiliary variables to estimate total aboveground biomass over a large study area in Eastern Amazonia, Brazil. Multipurpose surveys are also considered, where the totals of aboveground biomass, primary production, and clay content (3 responses) are estimated from a single well-spread sample over the auxiliary space.


Asunto(s)
Tamaño de la Muestra , Encuestas y Cuestionarios
17.
Sci Rep ; 14(1): 8107, 2024 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-38582778

RESUMEN

In 2023 Amazonia experienced both historical drought and warm conditions. On October 26th 2023 the water levels at the port of Manaus reached its lowest record since 1902 (12.70 m). In this region, October monthly maximum and minimum temperature anomalies also surpassed previous record values registered in 2015 (+ 3 °C above the normal considering the 1981-2020 average). Here we show that this historical dry and warm situation in Amazonia is associated with two main atmospheric mechanisms: (i) the November 2022-February 2023 southern anomaly of vertical integrated moisture flux (VIMF), related to VIMF divergence and extreme rainfall deficit over southwestern Amazonia, and (ii) the June-August 2023 downward motion over northern Amazonia related to extreme rainfall deficit and warm conditions over this region. Anomalies of both atmospheric mechanisms reached record values during this event. The first mechanism is significantly correlated to negative sea surface temperature (SST) anomalies in the equatorial Pacific (November-February La Niña events). The second mechanism is significantly correlated to positive SST anomalies in the equatorial Pacific, related to the impacts of June-September El Niño on the Walker Circulation. While previous extreme droughts were linked to El Niño (warmer North Tropical Atlantic SST) during the austral summer (winter and spring), the transition from La Niña 2022-23 to El Niño 2023 appears to be a key climatic driver in this record-breaking dry and warm situation, combined to a widespread anomalous warming over the worldwide ocean.

18.
Preprint en Inglés | SciELO Preprints | ID: pps-8304

RESUMEN

Colli-Silva et al.1 recently proposed that cupuaçu (Theobroma grandiflorum) was domesticated in northwestern Amazonia as a selection from its sister species, cupuí (T. subincanum). This proposal ignores long-term research in taxonomy, botany, biogeography, and genetics about Theobroma, including cupuaçu. Our review of the research that was ignored and of Colli-Silva et al.'s results demonstrates that cupuaçu is a valid species, as they now agree2, but cupuí may be paraphyletic, the distribution of wild cupuaçu was not included in their samples so the origin of domestication continues unknown, precolonial archaeology lacks remains that can be attributed to either species, historical linguistics indicates that the term cupuaçu references the species' wild distribution and is a recent introduction in northwestern Amazonia, history suggests that cupuaçu started to be domesticated during the last 100-200 years, and the genomics results are not about the domestication of cupuaçu because it is a valid species and its wild distribution was not sampled.

19.
Ecol Evol ; 14(3): e10860, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38450322

RESUMEN

Common distributional patterns have provided the foundations of our knowledge of Neotropical biogeography. A distinctive pattern is the "circum-Amazonian distribution", which surrounds Amazonia across the forested lowlands south and east of the basin, the Andean foothills, the Venezuelan Coastal Range, and the Tepuis. The underlying evolutionary and biogeographical mechanisms responsible for this widespread pattern of avian distribution have yet to be elucidated. Here, we test the effects of biogeographical barriers in four species in the passerine family Thamnophilidae by performing comparative demographic analyses of genome-scale data. Specifically, we used flanking regions of ultraconserved regions to estimate population historical parameters and genealogical trees and tested demographic models reflecting contrasting biogeographical scenarios explaining the circum-Amazonian distribution. We found that taxa with circum-Amazonian distribution have at least two main phylogeographical clusters: (1) Andes, often extending into Central America and the Tepuis; and (2) the remaining of their distribution. These clusters are connected through corridors along the Chaco-Cerrado and southeastern Amazonia, allowing gene flow between Andean and eastern South American populations. Demographic histories are consistent with Pleistocene climatic fluctuations having a strong influence on the diversification history of circum-Amazonian taxa, Refugia played a crucial role, enabling both phenotypic and genetic differentiation, yet maintaining substantial interconnectedness to keep considerable levels of gene flow during different dry/cool and warm/humid periods. Additionally, steep environmental gradients appear to play a critical role in maintaining both genetic and phenotypic structure.

20.
Cien Saude Colet ; 29(3): e16672023, 2024 Mar.
Artículo en Portugués, Inglés | MEDLINE | ID: mdl-38451656

RESUMEN

This study examined food insecurity in the Quilombola community of Imbiral Cabeça-Branca, in Maranhão, Brazil, during the COVID-19 pandemic. A cross-sectional study was conducted in the last quarter of 2021 with 25 household heads from the community. Most participants were women (52.0%) with low schooling and were unemployed (68.0%), and 76.0% received a Federal Emergency Aid. The mean household density was four people, and houses were predominantly made of rammed earth, lacking basic sanitation. The consumed water came from artesian wells, and most houses had electricity. Food insecurity was identified in all households, with 12.0% classified as mild, 24.0% as moderate, and 64.0% as severe. The severe form was more common in households headed by single men (75%), older adults, less-educated individuals (78.7%), and the unemployed (64.7%). Food insecurity in the Quilombola community and other similar communities in the country results from substandard living conditions, unemployment, food deprivation, and lack of land titling. These factors also contribute to the perpetuation of institutional and environmental racism faced by these communities.


Este estudo analisou a insegurança alimentar na comunidade quilombola Imbiral Cabeça-Branca, no Maranhão, durante a pandemia da COVID-19. Estudo transversal realizado no último trimestre de 2021, com 25 chefes de família da comunidade. A maioria dos participantes eram mulheres (52,0%), com baixa escolaridade, desempregados (68,0%), e 76,0% recebiam o Auxílio Emergencial federal. A densidade domiciliar média era de quatro pessoas, e as casas eram predominantemente de taipa, sem saneamento básico. A água consumida provinha de poços artesanais, e a maioria das casas tinha acesso à eletricidade. A insegurança alimentar foi identificada em todas as famílias, sendo 12,0% classificadas como Leve, 24,0% Moderada e 64,0% Grave. A forma Grave foi mais comum em lares chefiados por homens solteiros (75%), idosos, pessoas com baixa escolaridade (78,7%) e desempregados (64,7%). A insegurança alimentar na comunidade quilombola, assim como em outras comunidades similares no país, é resultado das condições precárias de vida, desemprego, privação de alimentos e falta de titulação de terras. Esses fatores também contribuem para a perpetuação do racismo institucional e ambiental enfrentado por essas comunidades.


Asunto(s)
Pandemias , Racismo , Masculino , Humanos , Femenino , Anciano , Brasil/epidemiología , Estudios Transversales , Inseguridad Alimentaria
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