Seasonal changes in water sources used by woody species in a tropical coastal dune forest

Autor(es)

Antunes, C. ^{[1, 2]} ; Silva, C. ^[3] ; Maguas, C. ^[1] ; Joly, C. A. ^[4] ; Vieira, S. ^[2]

Afiliação do(s) autor(es)

^[1] Univ Lisbon, CE3C, Fac Ciencias, Lisbon - Portugal

^[2] Univ Estadual Campinas, Lab Ecol & Manejo Ecossistemas, Nucleo Estudos & Pesquisas Ambientais, Sao Paulo - Brazil

^[3] Univ Estadual Campinas, PPG Biol Vegetal, Inst Biol, Sao Paulo - Brazil

^[4] Univ Estadual Campinas, Inst Biol, Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: PLANT AND SOIL; v. 437, n. 1-2, p. 41-54, APR 2019.
• Citações Web of Science: 1

Resumo

AimsOur aim was to investigate the water sources used by woody species under contrasting water availability and the extent of water-sources-use differentiation among dominant woody species in a tropical coastal dune forest.MethodsWe sampled 15 woody species in a Brazilian restinga forest and, through Bayesian isotope mixing models, we estimated the proportion of water sources used. We tested whether water-sources-use was (i) different between contrasting water availability conditions; (ii) dependent on growth form, plant size or crown illumination; and (iii) influenced by stand density, evenness or biomass.ResultsWe found a seasonal variation in water-sources-use, but no vertical soil-water partitioning among woody species. In wetter periods, plants used mainly water from top-soil, as a shallow water table limited water uptake to top-soil layers recharged with rainwater. Contrastingly, during drier periods, with the absence of rain and a deeper water table, plants generally relied on deeper (50 cm) soil layers. Only under less-wet conditions, a greater evenness and density implied higher water-uptake depth heterogeneity among plants. However, changes in the main water-sources used by plants were neither evoked in more dense or diverse plots, nor induced by plant size.ConclusionsOur study shows that restinga species have dynamic shifts in water-uptake depth caused by seasonal water availability changes, influenced by the combined effect of insufficient moisture at shallow soil layers and water-table lowering in drier periods. These temporal shifts are common among species, implying that restinga woody community has a homogeneous strategy of water-resources acquisition. This study enhances our understanding of the effects that water variations can have on water-resource use in restinga forests. (AU)

• Processo FAPESP: 12/51509-8 - Composição florística, estrutura e dinâmica do funcionamento da Floresta Ombrófila Densa Atlântica dos núcleos Caraguatatuba, Cunha, Picinguaba e Santa Virgínia, do Parque Estadual da Serra do Mar (PelD)
• Beneficiário: Carlos Alfredo Joly
• Modalidade de apoio: Auxílio à Pesquisa - Programa BIOTA - Regular
• Processo FAPESP: 12/51872-5 - ECOFOR: Biodiversidade e funcionamento de ecossistemas em áreas alteradas pelo homem nas Florestas Amazônica e Atlântica
• Beneficiário: Carlos Alfredo Joly
• Modalidade de apoio: Auxílio à Pesquisa - Programa BIOTA - Temático
• Processo FAPESP: 03/12595-7 - Composição florística, estrutura e funcionamento da Floresta Ombrófila Densa dos Núcleos Picinguaba e Santa Virgínia do Parque Estadual da Serra do Mar, estado de São Paulo, Brasil
• Beneficiário: Carlos Alfredo Joly
• Modalidade de apoio: Auxílio à Pesquisa - Programa BIOTA - Temático