Data/hora: 21/06/2024 14:23:56

Biblioteca(s): | Embrapa Amazônia Oriental.
Data corrente: | 24/04/2017
Data da última atualização: | 22/12/2021
Autoria: | BINKS, O.; MEIR, P.; ROWLAND, L.; COSTA, A. C. L. da; VASCONCELOS, S. S.; OLIVEIRA, A. A. R. de; FERREIRA, L.; MENCUCCINI, M.
Afiliação: | Oliver Binks, University of Edinburgh; Patrick Meir, University of Edinburgh / Australian National University; Lucy Rowland, University of Exeter; Antonio Carlos Lola da Costa, UFPA; STEEL SILVA VASCONCELOS, CPATU; Alex Antonio Ribeiro de Oliveira, UFPA; Leandro Ferreira, MPEG; Maurizio Mencuccini, University of Edinburgh / ICREA at CREAF.
Título: | Limited acclimation in leaf anatomy to experimental drought in tropical rainforest trees.
Ano de publicação: | 2016
Fonte/Imprenta: | Tree Physiology, v. 36, n. 12, p. 1550-1561, 2016.
DOI: | 10.1093/treephys/tpw078
Idioma: | Inglês
Conteúdo: | Dry periods are predicted to become more frequent and severe in the future in some parts of the tropics, including Amazonia, potentially causing reduced productivity, higher tree mortality and increased emissions of stored carbon. Using a long-term (12 year) through-fall exclusion (TFE) experiment in the tropics, we test the hypothesis that trees produce leaves adapted to cope with higher levels of water stress, by examining the following leaf characteristics: area, thickness, leaf mass per area, vein density, stomatal density, the thickness of palisade mesophyll, spongy mesophyll and both of the epidermal layers, internal cavity volume and the average cell sizes of the palisade and spongy mesophyll. We also test whether differences in leaf anatomy are consistent with observed differential drought-induced mortality responses among taxa, and look for relationships between leaf anatomy, and leaf water relations and gas exchange parameters. Our data show that trees do not produce leaves that are more xeromorphic in response to 12 years of soil moisture deficit. However, the drought treatment did result in increases in the thickness of the adaxial epidermis (TFE: 20.5 ± 1.5 µm, control: 16.7 ± 1.0 µm) and the internal cavity volume (TFE: 2.43 ± 0.50 mm3 cm?2, control: 1.77 ± 0.30 mm3 cm?2). No consistent differences were detected between drought-resistant and drought-sensitive taxa, although interactions occurred between drought-sensitivity status and drought treatment for the palisade mesophyll thickness (P = 0.034) and the cavity volume of the leaves (P = 0.025). The limited response to water deficit probably reflects a tight co-ordination between leaf morphology, water relations and photosynthetic properties. This suggests that there is little plasticity in these aspects of plant anatomy in these taxa, and that phenotypic plasticity in leaf traits may not facilitate the acclimation of Amazonian trees to the predicted future reductions in dry season water availability.
Palavras-Chave: | Estresse hídrico; Fisiologia foliar; Relações hídricas.
Thesagro: | Aclimatação; Floresta Tropical.
Thesaurus Nal: | Amazonia.
Categoria do assunto: | K Ciência Florestal e Produtos de Origem Vegetal
Registro original: | Embrapa Amazônia Oriental (CPATU)
Exemplares: | CPATU - (53704-1) - UPC - AP - DD -  -  -  - DIS