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1.
Am J Bot ; 110(9): e16214, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37475703

RESUMO

PREMISE: Plants survive in habitats with limited resource availability and contrasting environments by responding to variation in environmental factors through morphophysiological traits related to species performance in different ecosystems. However, how different plant strategies influence the megadiversity of tropical species has remained a knowledge gap. METHODS: We analyzed variations in 27 morphophysiological traits of leaves and secondary xylem in Erythroxylum pulchrum and Tapirira guianensis, which have the highest absolute dominance in these physiognomies and occur together in areas of restinga and dense ombrophilous forest to infer water-transport strategies of Atlantic Forest woody plants. RESULTS: The two species presented different sets of morphophysiological traits, strategies to avoid embolism and ensure water transport, in different phytophysiognomies. Tapirira guianensis showed possible adaptations influenced by phytophysiognomy, while E. pulchrum showed less variation in the set of characteristics between different phytophysiognomies. CONCLUSIONS: Our results provide essential tools to understand how the environment can modulate morphofunctional traits and how each species adjusts differently to adapt to different phytophysiognomies. In this sense, the results for these species reveal new species-specific responses in the tropical forest. Such knowledge is a prerequisite to predict future development of the most vulnerable forests as climate changes.


Assuntos
Ecossistema , Árvores , Árvores/fisiologia , Clima Tropical , Água/fisiologia , Florestas , Folhas de Planta/fisiologia
2.
AoB Plants ; 15(3): plad018, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37214224

RESUMO

Amazonian savannas are isolated patches of open habitats found within the extensive matrix of Amazonian tropical forests. There remains limited evidence on how Amazonian plants from savannas differ in the traits related to drought resistance and water loss control. Previous studies have reported several xeromorphic characteristics of Amazonian savanna plants at the leaf and branch levels that are linked to soil, solar radiation, rainfall and seasonality. How anatomical features relate to plant hydraulic functioning in this ecosystem is less known and instrumental if we want to accurately model transitions in trait states between alternative vegetation in Amazonia. In this context, we combined studies of anatomical and hydraulic traits to understand the structure-function relationships of leaf and wood xylem in plants of Amazonian savannas. We measured 22 leaf, wood and hydraulic traits, including embolism resistance (as P50), Hydraulic Safety Margin (HSM) and isotope-based water use efficiency (WUE), for the seven woody species that account for 75% of the biomass of a typical Amazonian savanna on rocky outcrops in the state of Mato Grosso, Brazil. Few anatomical traits are related to hydraulic traits. Our findings showed wide variation exists among the seven species studied here in resistance to embolism, water use efficiency and structural anatomy, suggesting no unique dominant functional plant strategy to occupy an Amazonian savanna. We found wide variation in resistance to embolism (-1.6 ± 0.1 MPa and -5.0 ± 0.5 MPa) with species that are less efficient in water use (e.g. Kielmeyera rubriflora, Macairea radula, Simarouba versicolor, Parkia cachimboensis and Maprounea guianensis) showing higher stomatal conductance potential, supporting xylem functioning with leaf succulence and/or safer wood anatomical structures and that species that are more efficient in water use (e.g. Norantea guianensis and Alchornea discolor) can exhibit riskier hydraulic strategies. Our results provide a deeper understanding of how branch and leaf structural traits combine to allow for different hydraulic strategies among coexisting plants. In Amazonian savannas, this may mean investing in buffering water loss (e.g. succulence) at leaf level or safer structures (e.g. thicker pit membranes) and architectures (e.g. vessel grouping) in their branch xylem.

3.
Data Brief ; 30: 105484, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32373679

RESUMO

This paper presents additional data on the leaf structural, physiological and nutritional characteristics of three species (Maytenus obtusifolia, Manilkara subsericea e Inga laurina), co-occurring in restinga and semideciduous seasonal forest (forest). The data of the leaf structural, physiological and nutritional characteristics were obtained from the three species to identify possible adaptive strategies that could explain the co-occurrence of these species in the restinga and forest. In addition, this data can help identify key functional traits in the plant community of restinga and forests that can be employed in the reestablishment of ecological and edaphic processes in these ecosystems. This work presents data complementary to the published article "Acclimatization capacity of leaf traits of species co-occurring in restinga and seasonal semideciduous forest ecosystems" [1].

4.
Acta sci., Biol. sci ; 40: 37334-37334, 20180000. ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1460814

RESUMO

Savannas of the Amazon Region of Mato Grosso State have an unique ecological identity due to the complexity of the Cerrado-Amazon transition region, their geographical isolation and the physical-chemical properties of the soil. This study aimed to characterize the leaf anatomy of Xylopia aromatica, and to identify potential adaptive traits to the xeric environment. We collected adult leaves from X. aromatica from a Amazonian savannah located in the Nova Canãa do Norte city, Mato Grosso. The leaves were fixed and stored in 70% ethanol. Cross sections were obtained by free hand with the aid of a razor blade, stained with astra blue and basic fuchsin, and mounted on histological slides. Charactersconsidered adaptive: thick cuticle, epidermal cells with thickened walls, the presence of silica in theepidermis, trichomes, hypostomatic leaves, stomata on the same level as the other epidermal cells, presenceof hypodermis, and dorsiventral mesophyll with palisade parenchyma occupying more than 50%. Theanatomical characters presented are of great importance for the establishment and development of X.aromatica in xeric environments. They contribute to the protection of the leaves from many biotic andabiotic factors to which they are subjected, thus ensuring the species survival in the savannic environment.


A região de savana amazônica do Estado do Mato Grosso possui identidade ecológica própria, explicada pela complexa região de transição Cerrado-Amazônia, pelo isolamento geográfico e pelas propriedades físico-químicas do solo. O objetivo deste estudo foi caracterizar a anatomia foliar de Xylopiaaromatica (Lam.) Mart, identificando possíveis características adaptativas ao ambiente xerófilo. Foram coletadas folhas adultas de X. aromatica em savana amazônica, localizado no município de Nova Canaã do Norte - Mato Grosso. As folhas foram fixadas em FAA50 e armazenadas em etanol a 70%. Os cortes transversais foram obtidos a mão livre com auxílio de lâmina de barbear, corados com azul de Astra e fucsina básica e montados em lâminas histológicas. Caracteres aqui considerados adaptativos: cutículaespessa, células epidérmicas com paredes espessadas, presença de sílica na epiderme, tricomas, folhashipoestomáticas, estômatos no mesmo nível das demais células epidérmicas, presença de hipoderme, mesofilo dorsiventral com parênquima paliçádico ocupando mais de 50% e lacunoso bem compacto. Os caracteres anatômicos aqui apresentados são de grande importância para as espécies desenvolverem-se em ambientes xerófilos, demonstrando contribuição para a proteção das folhas a diversos fatores bióticos e abióticos aos quais esta se sujeita, garantindo a sobrevivência das espécies no ambiente savânico.


Assuntos
Annonaceae/anatomia & histologia , Annonaceae/crescimento & desenvolvimento , Pradaria
5.
Pensando fam ; 21(2): 28-44, dez. 2017. tab
Artigo em Português | LILACS | ID: biblio-895229

RESUMO

Objetivo: avaliar o gerenciamento da renda de casais heterossexuais, de classe média, com renda individual, identificando aspectos positivos e negativos e se o gerenciamento é distinto entre casais cuja maior renda é da esposa ou do marido. Participantes: oito casais com idade entre 25 a 35 anos. Instrumentos: entrevista aberta, verificando a administração financeira individual e familiar, como são tomadas decisões financeiras, conhecimento de ambos sobre a renda e gastos do parceiro. Procedimentos: Entrevista individual com cada cônjuge. Resultados: Realizou-se análise de conteúdo qualitativa e quantitativa por meio de categorias de respostas. Em três casais o homem gerencia a renda, três deles compartilham entradas e despesas financeiras e dois dividem as despesas. As mulheres foram mais propensas a cometer infidelidade financeira. A satisfação financeira relacionou-se à consulta ao cônjuge em relação aos investimentos e aquisição de bens e a insatisfação aos gastos sem planejamento.(AU)


Objective: To evaluate the management of the income of heterosexual couples, middle-class, with individual income, identifying strengths and weaknesses and the management is distinct among couples whose income is greater with the wife or husband. Participants: Eight couples aged 25 to 35 years. Instruments: open interviews, checking the individual and family financial management, such as financial decisions, knowledge of both on income and partner spending are taken. Procedures: Individual interview with each spouse. Results: An analysis of qualitative and quantitative content through categories of answers. In three couples man manages income, three of them share financial income and expenses and two share the costs. Women were more likely to commit financial infidelity. The financial satisfaction was related to consulting the spouse for investments and acquisition of goods and dissatisfaction to spending without planning.(AU)


Assuntos
Humanos , Casamento , Administração Financeira/organização & administração , Renda
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