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Estrutura funcional de uma comunidade de palmeiras (Arecaceae) ao longo de gradientes ambientais em uma floresta da Amazônia Central
Get PDFThe functional approach allows us to understand how the environment selects the characteristics of the species that form the communities, and therefore how communities can be modified according to new conditions, such as those induced by climate change. Two forces can functionally structure a community: convergence, which promotes similarity of functional characteristics, and divergence, which promotes variability. Theoretically, it is expected that the environmental filters cause convergence, since they select characteristics suitable for the occupation of each environment. Contrarily, it is expected that biotic interactions and disturbances promote functional divergence by increasing environmental heterogeneity, selecting species with multiple functional strategies. Using palm trees (Arecaceae), an abundant and diverse way of life in the Amazon, as model group we analyze which environmental factors are responsible for generating convergence and functional divergence in local communities. This study was developed in the Adolpho Ducke Forest Reserve, where seven functional characteristics were observed that affect photosynthetic performance, balance and hydraulic safety and leaf economy (stomatal density, stomata size, venation density, dry matter content, leaf thickness, area specific leaf and estimated leaf area) of the 14 most abundant species of the reserve. We tested models including hydrological conditions and soil fertility as resource gradients and the mortality rate of trees as a proxy for the intensity of disturbance. Our results show that: 1) there is a functional differentiation between the hydrological environments, and in the plateaus conservative strategies are selected while in the bottomlands acquisitive strategies are favoured, 2) hydrological environments are the main filter of the functional composition 3) in the bottomlands there is a greater functional divergence of all the characteristics, while in the lowlands functional convergence and 4) the intensity of disturbance can generate both convergence and functional divergence. This means that the functional characteristics are selected mainly by the hydrological conditions of the soil, the disturbances can lead to convergence when its intensity is low and the divergence, when it increases the spatial and temporal heterogeneity of resources. Also, the variability of all the characteristics is greater in the lowlands, since the environmental heterogeneity existing in these places and the plateaus tend to have greater internal convergence due to the low dynamism and the spatial and temporal availability of resources. Thus, convergence is associated with responses to abiotic filters as the ecological theory of communities addresses, but contrary to what is predicted for processes that generate divergence, abiotic disturbances can also generate functional divergence.A abordagem funcional nos permite entender como o ambiente seleciona as características das espécies que formam as comunidades e, portanto, como as comunidades poderão ser modificadas em função de novas condições, como as induzidas por mudanças climáticas. Duas forças podem estruturar funcionalmente uma comunidade: a convergência, que promove similaridade das características funcionais, e a divergência, que leva à variabilidade. Teoricamente, espera-se que os filtros ambientais causem convergência, por selecionarem características adequadas para a ocupação de cada ambiente. Por outro lado, espera-se que interações bióticas e distúrbios promovam divergência funcional, por aumentarem a heterogeneidade ambiental, selecionando espécies com múltiplas estratégias funcionais. Tendo como modelo as palmeiras (Arecaceae), uma forma de vida abundante e diversa na Amazônia, analisamos quais fatores ambientais são responsáveis por gerar convergência e divergência funcional nas comunidades locais. Esse estudo foi desenvolvido na Reserva Florestal Adolpho Ducke, onde foram medidas sete características funcionais que afetam o desempenho fotossintético, balanço e segurança hidráulica e economia foliar (densidade estomática, tamanho dos estômatos, densidade de venação, conteúdo da matéria seca, espessura das folhas, área foliar específica e área estimada da lâmina) das 14 espécies mais abundantes da reserva. Foram testados modelos incluindo as condições hidrológicas e fertilidade do solo como gradientes de recurso e a taxa de mortalidade de árvores como um indicativo para a intensidade de distúrbio. Nossos resultados mostram que: 1) há diferenciação funcional entre os ambientes hidrológicos, sendo que nos platôs são selecionadas estratégias conservativas e nos baixios aquisitivas, 2) os ambientes hidrológicos são o principal filtro da composição funcional 3) nos baixios existe maior divergência funcional de todas as características, enquanto que nos platôs convergência funcional e 4) a intensidade de distúrbio pode gerar tanto convergência quanto divergência funcional. Isso significa que, as características funcionais são selecionadas principalmente pelas condições hidrológicas do solo, sendo os distúrbios podem levar à convergência quando a sua intensidade for baixa e à divergência, quando aumenta a heterogeneidade espacial e temporal de recursos,. Ainda, a variabilidade de todas as características é maior nos baixios, pois a heterogeneidade ambiental existente nesses locais e os platôs tendem a ter maior convergência interna devido ao baixo dinamismo e disponibilidade espacial e temporal de recursos. Sendo assim, a convergência está associada com respostas aos filtros abióticos conforme a teoria ecológica de comunidades aborda, mas contrário do que prediz quanto aos processos que geram divergência, os distúrbios abióticos também podem gerar divergência funcional
Plantas medicinais conhecidas dos moradores do distrito de Riozinho, Cacoal/RO e aspectos morfoanatômicos, histoquímicos e fitoquímicos de Fridericia chica (Bonpl.) L. G. Lohmann - crajiru - Bignoniaceae
Get PDFThe use of medicinal plants is a common practice among human populations. The objective of this work was to conduct an ethnobotanical study on medicinal plants known by a community located in the Municipality of Cacoal in the State of Rondônia. And contribute to the pharmacognostic characterization of one of the most common species of use in the community, Fridericia chica (Bignoniaceae). In the ethnobotanical study, the informants were selected through the "Snowball" technique. Semi-structured interviews and guided tours were conducted. The agreement of main use (AMU) and value of use (VU) of the species were calculated. The morphological, histochemical and phytochemical characterization of the F. chica leaves were performed according to the usual laboratory methodologies. The informants are mostly women. A total of 89 medicinal species were identified and distributed in 42 families, with Lamiaceae, Asteraceae and Fabaceae being the most represented families. Most of the medicinal plants used are herbaceous, which corroborates the idea of the importance of these "weed" plants in popular pharmacopoeias, and found in backyards, which reflects the importance of domestication of appropriate plants for therapeutic purposes. Plectranthus barbatus (Lamiaceae) and F. chica (Bignoniaceae) are the highest AMU and VU plants in the locality. The leaves are the vegetable parts most used in the preparation of the remedies, with infusion and decoction being the most common methods. The action of conventional medicine in the community seems to be a factor influencing the number of medicinal species used. The leaves of F. chica have uniseriate epidermis, dorsiventral mesophyll, are hypoestomatic with anomocytic stomata. Rosy-shaped glandular trichomes are distributed on both surfaces of the leaf blade, the central vein and the petiole. Coronal trichomes are present in the central rib and petiole region. The petiole is cylindrical, consisting of an unstrapped epidermis and fine cuticle. Histochemical tests indicated the presence of several secondary metabolites such as tannins, lignins, proteins and phenolic compounds and the phytochemical profile revealed the presence of flavonoids, anthraquinones and terpenes. These results indicate the great therapeutic potential of the species.O uso de plantas medicinais é uma prática comum entre as populações humanas. Este trabalho teve como objetivo realizar um estudo etnobotânico de plantas medicinais conhecidas por uma comunidade localizada no Município de Cacoal interior do Estado de Rondônia. E contribuir com a caracterização farmacognóstica de uma das espécies de maior consenso de uso na comunidade, Fridericia chica (Bonpl.) L. G. Lohmann (Bignoniaceae). No estudo etnobotânico, os informantes foram selecionados através da técnica “Bola de neve”. Foram realizadas entrevistas semiestruturadas e turnê guiada. Foi calculada a concordância de uso principal (CUP) e o valor de uso (VU) das espécies. Foi realizada a caracterização morfoanatômica, histoquímica e fitoquímica das folhas de F. chica, segundo metodologias usuais de laboratório. Os informantes são em sua maioria mulheres. Foram repertoriadas na comunidade 89 espécies medicinais identificadas, distribuídas em 42 famílias, sendo as famílias mais representadas Lamiaceae, Asteraceae, Fabaceae. A maioria das plantas medicinais usadas é herbácea, o que corrobora a ideia da importância destas plantas em farmacopeias populares e encontrada nos quintais, o que reflete a importância da domesticação das plantas com fins terapêuticos. Plectranthus barbatus. (Lamiaceae) e F. chica (Bignoniaceae) são as plantas com CUP e VU mais elevados na localidade. As folhas são as partes vegetais mais usadas na preparação dos remédios, sendo a infusão e decocção os métodos mais comuns. A prática da medicina convencional na comunidade parece ser um fator de influência no número de espécies medicinais utilizadas. As folhas de F. chica apresentam epiderme unisseriada, mesofilo dorsiventral, são hipoestomáticas com estômatos anomocíticos. Tricomas glandulares em forma de roseta estão distribuídos em ambas as superfícies do limbo foliar, da nervura central e do pecíolo. Tricomas tectores estão presentes na região da nervura central e do pecíolo. O pecíolo é cilíndrico, constituído por uma epiderme uniestratificada e cutícula fina. Os testes histoquímicos apontaram a presença de diversos metabólitos secundários como tanino, lignina, proteína e compostos fenólicos e o perfil fitoquímico revelou a presença de flavonoides, antraquinonas e terpenos. Tais resultados indicam o grande potencial terapêutico e a multiplicidade de uso desta espécie para a comunidade
Description of the mature larva and pupa of Ora semibrunnea Pic (Coleoptera: Scirtidae) with notes on its biology
No full textIn this paper we describe and illustrate for the first time the immature forms (larva and pupa) of Ora semibrunnea Pic, 1922, including biological information and behavior observed in the laboratory. This is the first record of the occurrence of this species in the Brazilian Amazon region. Larvae and pupae were found in natural lakes associated with macrophyte banks. Pupae are aquatic and have morphological adaptations (well-developed pronotal siphons) to obtain atmospheric O 2 at the water surface. Copyright © 2019 Magnolia Pres
Habitat use of the ocelot (Leopardus pardalis) in Brazilian Amazon
Get PDFAmazonia forest plays a major role in providing ecosystem services for human and sanctuaries for wildlife. However, ongoing deforestation and habitat fragmentation in the Brazilian Amazon has threatened both. The ocelot is an ecologically important mesopredator and a potential conservation ambassador species, yet there are no previous studies on its habitat preference and spatial patterns in this biome. From 2010 to 2017, twelve sites were surveyed, totaling 899 camera trap stations, the largest known dataset for this species. Using occupancy modeling incorporating spatial autocorrelation, we assessed habitat use for ocelot populations across the Brazilian Amazon. Our results revealed a positive sigmoidal correlation between remote-sensing derived metrics of forest cover, disjunct core area density, elevation, distance to roads, distance to settlements and habitat use, and that habitat use by ocelots was negatively associated with slope and distance to river/lake. These findings shed light on the regional scale habitat use of ocelots and indicate important species–habitat relationships, thus providing valuable information for conservation management and land-use planning. © 2019 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd
Amazon forest response to CO2 fertilization dependent on plant phosphorus acquisition
No full textGlobal terrestrial models currently predict that the Amazon rainforest will continue to act as a carbon sink in the future, primarily owing to the rising atmospheric carbon dioxide (CO2) concentration. Soil phosphorus impoverishment in parts of the Amazon basin largely controls its functioning, but the role of phosphorus availability has not been considered in global model ensembles—for example, during the Fifth Climate Model Intercomparison Project. Here we simulate the planned free-air CO2 enrichment experiment AmazonFACE with an ensemble of 14 terrestrial ecosystem models. We show that phosphorus availability reduces the projected CO2-induced biomass carbon growth by about 50% to 79 ± 63 g C m−2 yr−1 over 15 years compared to estimates from carbon and carbon–nitrogen models. Our results suggest that the resilience of the region to climate change may be much less than previously assumed. Variation in the biomass carbon response among the phosphorus-enabled models is considerable, ranging from 5 to 140 g C m−2 yr−1, owing to the contrasting plant phosphorus use and acquisition strategies considered among the models. The Amazon forest response thus depends on the interactions and relative contributions of the phosphorus acquisition and use strategies across individuals, and to what extent these processes can be upregulated under elevated CO2. © 2019, The Author(s), under exclusive licence to Springer Nature Limited
Discovering floristic and geoecological gradients across Amazonia
No full textAim: To map and interpret floristic and geoecological patterns across the Amazon basin by combining extensive field data with basin-wide Landsat imagery and climatic data. Location: Amazonia. Taxon: Ground truth data on ferns and lycophytes; remote sensing results reflect forest canopy properties. Methods: We used field plot data to assess main ecological gradients across Amazonia and to relate floristic ordination axes to soil base cation concentration, Climatologies at High Resolution for the Earth's Land Surface Areas (CHELSA) climatic variables and reflectance values from a basin-wide Landsat image composite with generalized linear models. Ordination axes were then predicted across all Amazonia using Landsat and CHELSA, and a regional subdivision was obtained using k-medoid classification. Results: The primary floristic gradient was strongly related to base cation concentration in the soil, and the secondary gradient to climatic variables. The Landsat image composite revealed a tapestry of broad-scale variation in canopy reflectance characteristics across Amazonia. Ordination axis scores predicted using Landsat and CHELSA variables produced spatial patterns consistent with existing knowledge on soils, geology and vegetation, but also suggested new floristic patterns. The clearest dichotomy was between central Amazonia and the peripheral areas, and the available data supported a classification into at least eight subregions. Main conclusions: Landsat data are capable of predicting soil-related species compositional patterns of understorey ferns and lycophytes across the Amazon basin with surprisingly high accuracy. Although the exact floristic relationships may differ among plant groups, the observed ecological gradients must be relevant for other plants as well, since surface reflectance recorded by satellites is mostly influenced by the tree canopy. This opens exciting prospects for species distribution modelling, conservation planning, and biogeographical and ecological studies on Amazonian biota. Our maps provide a preliminary geoecological subdivision of Amazonia that can now be tested and refined using field data of other plant groups and from hitherto unsampled areas. © 2019 John Wiley & Sons Lt
Levantamento Faunístico De Flebotomíneos (Diptera, Psychodidae) Na Unidade De Conservação Flona Estadual Sustentável Antimary-Fes Antimary, Acre
No full textMaking the most of scarce data: Mapping soil gradients in data-poor areas using species occurrence records
No full textMaps of environmental characteristics are needed to improve our understanding of species distributions and ecosystem dynamics. Despite the growing demand for digital environmental maps, scarcity of environmental field samples to be used as input data often constrains the accuracy of such maps, especially for soils. We developed and tested a method that combines information on species–environment associations and the spatial distribution of indicator species (as retrieved from repositories such as GBIF) to improve mapping accuracy of environmental variables. Our approach includes: (a) Compile field data on the environmental variable of interest (direct environmental data) and documented occurrences of the species to be used as indicators; (b) define species optima for the environmental variable; (c) use georeferenced records of the indicator species to calculate species-based environmental values (indirect environmental data); (d) generate maps using direct and indirect environmental data as input data for interpolation; (e) validate the maps. We applied the method to map the concentration of exchangeable base cations in Amazonian soils using fern and lycophyte species as indicators. Including soil values that had been indirectly estimated using indicator species represented a 12-fold increase in the number of input data points used for mapping. At the same time, map accuracy improved considerably: the correlation between mapped soil cation concentration estimates and field-measured values from an independent validation dataset increased from r = 0.48 to r = 0.71. Knowledge on species–environment relationships can be useful for modelling ecologically relevant environmental variables in areas where species occurrence data are more readily available than direct environmental measurements. The method works even with haphazard species occurrence points obtained from public repositories such as GBIF and can be applied to other environmental variables and other indicator groups, provided that the environmental variable of interest is relevant as a determinant of species occurrences in the indicator group. The Amazonian soil cation concentration maps produced (available at https://doi.pangaea.de/10.1594/PANGAEA.879542) can be used as digital layers in species distribution and habitat modelling, and to guide conservation actions in Amazonia. © 2019 The Authors. Methods in Ecology and Evolution © 2019 British Ecological Societ