The intrinsic effects of environment and space on the composition of woody plant species vary between Brazilian savannas growing on distinct types of substrate
The relationship between the floristic composition of communities and the underlying environmental and spatial determinants is still the subject of intense debate, mainly because only recently has geographical distance been cited as an important driver of plant communities. We analysed environmental (elevation, climate and soil properties [E]) and spatial (geographic distance [S]) effects on the floristic composition of savannas on different substrates, one on a steep relief with shallow and rocky soils, and the other on flat terrain with deep soils. We show that: (1) savannas on rocky soils soils contain more nutrients, are more acidic and have a finer texture than savannas on deep soils; (2) that the dissimilarity between the rocky soils and deep soils is associated mainly with variation in altitude and soil properties and (3) that the individual and combined contributions of the environment and space to the floristic composition of woody plants differs between savannas on deep and rocky soils. Spatially structured environmental variation [E] + [S] explained 29% of the floristic composition variation in savannas on rocky soils and 41% in savannas on deep soils. In the rocky soils, the pure fraction explained by the [E] was larger (10%) than that recorded for deep soils (4%), but the pure effect of space [S] explained 2 and 3% of the variation on rocky and deep soils, respectively. The environmental variables analysed here are therefore strongly structured in space on both rocky and deep soils, but the total and combined environmental and spatial effects are larger in savannas on deep soils than in those on rocky soils.
KeywordsBrazilian savanna Floristic differentiation Spatial processes Substrate properties
We are grateful to the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) for the concession of a graduate scholarship and financial support through the PROCAD UnB/UNEMAT project (Proc. 88881.068430-2014-01). We also thank the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) for financial support through the SISBIOTA (Proc. 563320-2010-9), PPBio Cerrado (Proc. 457587-2012), PELD-TRAN (Proc. 558069/2009-6) and ‘Phytogeography, diversity and functional traits of woody vegetation in savannas of Serra do Roncador, Mato Grosso east: soil and spatial influences and implications for conservation’ (Proc. 447542/2014-1) projects. We are also grateful to the TROBIT (Tropical Biomes in Transition – Long-Term Ecological Studies) for financial support. We thank Thiago Bernardi Vieira for his assistance with the statistical analyses.
- Borcard D, Gillet F, Legendre P (2011) Numerical ecology with R. New YorkGoogle Scholar
- Dray S (2013) spacemakeR: spatial modelling. In R Package version 0.0-5/r113. Available at http://r-forge.r-project.org/projects/sedar
- Dray S, Pélissier R, Couteron P, Fortin M-J, Legendre P, Peres-Neto PR, Bellier E, Bivand R, Blanchet FG, De Cáceres M, Dufour A-B, Heegaard E, Jombart T, Munoz F, Oksanen J, Thioulouse J, Wagner HH (2012) Community ecology in the age of multivariate multiscale spatial analysis. Ecol Monogr 82:257–275CrossRefGoogle Scholar
- Dray S, Legendre P, Blanchet G (2013) packfor: forward selection with permutation. R Package version 0.0-8/r109. Available at https://rdrr.io/rforge/packfor
- Embrapa (2006) Sistema brasileiro de classificação de solos. 2a edição. Rio de Janeiro Google Scholar
- Giraudoux P (2015) pgirmess: data analysis in ecology. R Package version 1.6.2. Available at http://cran.r-project.org/package=pgirmess
- Haridasan M (2000) Nutrição mineral das plantas nativas do Cerrado. Revista Brasil Fisiol Veg 12:68–83Google Scholar
- Maracahipes-Santos L, Lenza E, dos Santos JO, Marimon BS, Eisenlohr PV, Marimon Junior BH, Feldpausch TR (2015) Diversity, floristic composition, and structure of the woody vegetation of the Cerrado in the Cerrado – Amazon transition zone in Mato Grosso, Brazil. Brazil J Bot 38:877–887CrossRefGoogle Scholar
- Mendonça RC, Felfili JM, Walter BT, Silva Junior MC, Rezende AV, Filgueiras TS, Nogueira PE, Fagg CW (2008) Flora Vascular do bioma Cerrado: checklist com 12.356 espécies. In Sano SM, Almeida SP, Ribeiro JF (eds) Cerrado: ecologia e flora. Embrapa-CPAC, Planaltina, pp 421–1279Google Scholar
- R Core Team (2017) R: a language and environment for Statistical Computing. R Found. Stat. Comput. Vienna, AustriaGoogle Scholar
- Ribeiro JF, Walter BMT (2008) As principais fitofisionomias do bioma Cerrado. In Sano SM, Almeida SP, Ribeiro JF (eds) Cerrado: ecologia e flora. Embrapa-CPAC, Planaltina, pp 151–212Google Scholar
- Wilkinson L (2011) venneuler: Venn and Euler diagrams. R Package version 1.1-0. Available at http://cran.r-project.org/package=venneuler