J Plant Ecol ›› 2018, Vol. 11 ›› Issue (6): 803-814 .DOI: 10.1093/jpe/rty017

• Research Articles • Previous Articles     Next Articles

Water availability drives gradients of tree diversity, structure and functional traits in the Atlantic–Cerrado–Caatinga transition, Brazil

Marcela de Castro Nunes Santos Terra1,*, Rubens Manoel dos Santos1, Jamir Afonso do Prado Júnior2, José Marcio de Mello1, José Roberto Soares Scolforo1, Marco Aurélio Leite Fontes1, Ivan Schiavini2, Aliny Aparecida dos Reis1, Inacio Thomaz Bueno1, Luiz Fernando Silva Magnago3 and Hans ter Steege4,5   

  1. 1 Departamento de Ciências Florestais, Universidade Federal de Lavras, Campus Universitário, PO Box 3037, Lavras, Minas Gerais 37200-000, Brazil
    2 Instituto de Biologia, Universidade Federal de Uberlandia, Campus Umuarama - Bloco 2D, PO Box 593, Uberlandia, Minas Gerais 38400-902, Brazil
    3 Applied Ecology and Conservation Lab, Programa de Pós‐gradua??o Ecologia e Conserva??o da Biodiversidade, Universidade Estadual de Santa Cruz, Ilhéus, Bahia 45662-900, Brazil
    4 Naturalis Biodiversity Center, Vondellaan 55, Postbus 9517, 2300 RA Leiden, The Netherlands
    5 Coordena??o de Botanica, Museu Paraense Emílio Goeldi, Av. Magalh?es Barata 376, PO Box 399, Belém, Para′ 66040-170,
    Brazil
    *Correspondence address. Departamento de Ciências Florestais, Universidade Federal de Lavras, Campus Universitário, PO Box 3037, Lavras, Minas Gerais 37200-000, Brazil. Tel: +55 35 99148 3000; E-mail: marcelacns@gmail.com
  • Received:2017-08-08 Revised:2018-04-25 Accepted:2018-05-31 Online:2018-06-04 Published:2018-12-21

Abstract:

Aims

Climate and soil are among the most important factors determining variation in tree communities, but their effects have not been thoroughly elucidated to date for many vegetation features. In this study, we evaluate how climate and soil gradients affect gradients of vegetation composition, species diversity and dominance, structure and functional traits (seed mass and wood density) using over 327 000 trees in 158 sites distributed along environmental gradients in the transitions among the Atlantic forest, Cerrado and Caatinga in Minas Gerais State (MG), Brazil (nearly 600 000 km2).

Methods

Gradients in species, genus and family abundance in addition to basal area, stem density, species diversity (Fisher’s alpha), dominance percentage, seed mass and wood density were correlated using multiple regressions with environmental variables, as summarized in four principal component analysis axes (two climatic—precipitation seasonality and temperature range—and two edaphic—soil fertility and soil moisture). Additionally, ordinary kriging maps were used to better illustrate the gradients.

Important Findings

Multiple regression models indicate that all variables but dominance percentage were affected by one or more of the environmental gradients, but the average R2 was low (26.25%). Kriging maps reinforced the patterns observed in the regression models. Precipitation seasonality and soil moisture gradients were the most important gradients affecting vegetation features. This finding suggests that water availability is an important determinant of vegetation features in these vegetation transitions.

Key words: climate, environmental gradient, soil, southeastern Brazil, vegetation