@Article{CordeiroRoGrTuZaFeCo:2016:ImSePr,
author = "Cordeiro, Carlos Leandro de Oliveira and Rossetti, Dilce de
F{\'a}tima and Gribel, Rog{\'e}rio and Tuomisto, Hanna and Zani,
Hiran and Ferreira, Carlos A. C. and Coelho, Luiz",
affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {Instituto
Nacional de Pesquisas Espaciais (INPE)} and Jardim Bot{\^a}nico,
Rio de Janeiro and {University of Turku} and {Instituto Nacional
de Pesquisas Espaciais (INPE)} and {Instituto Nacional de
Pesquisas da Amaz{\^o}nia (INPA)} and {Instituto Nacional de
Pesquisas da Amaz{\^o}nia (INPA)}",
title = "Impact of sedimentary processes on white-sand vegetation in an
Amazonian megafan",
journal = "Journal of Tropical Ecology",
year = "2016",
volume = "32",
pages = "498--509",
month = "Nov.",
keywords = "Amazonian, megafan, open vegetation, sedimentary dynamics,
white-sand vegetation.",
abstract = "Amazonian white-sand vegetation has unique tree communities
tolerant to nutrient-poor soils of interest for interpreting
processes of adaptation in neotropical forests. Part of this
phytophysionomy is confined to Late Quaternary megafan
palaeo-landforms, thus we posit that sedimentary disturbance is
the main ecological factor controlling tree distribution and
structuring in this environment. In this study, we characterize
the topographic trend of one megafan palaeo-landform using a
digital elevation model and verify its relationship to the forest
by modelling the canopy height with remote sensing data. We also
compare the composition and structure (i.e. canopy height and
diameter at breast height) of tree groups from the outer and inner
megafan environments based on the integration of remote sensing
and floristic data. The latter consist of field inventories of
trees >= 10 cm dbh using six (500 x 20 m) plots in varzea, terra
firme and igapo from the outer megafan and 20 (50 x 20 m) plots in
woodlands and forests from the inner megafan. The unweighted pair
group method with arithmetic mean (UPGMA) and the non-metric
multidimensional scaling (NMDS) were applied for clustering and
dissimilarity analyses, respectively. The megafan is a
sand-dominated triangular wetland with a topographic gradient of <
15 cm km(-1), being more elevated along its axis. The outer
megafan has a higher number of tree species (367), taller canopy
height (mean of 14.1 m) and higher diameter at breast height (mean
of 18.2 cm) than the white-sand forest. The latter records 89 tree
species, mean canopy height of 8.4 cm and mean diameter at breast
height of 15.3 cm. Trees increase in frequency closer to channels
and toward the megafan's axis. The flooded and nutrient-poor sandy
megafan substrate favoured the establishment of white-sand
vegetation according to the overall megafan topography and
morphological heterogeneities inherent to megafan
sub-environments.",
doi = "10.1017/S0266467416000493",
url = "http://dx.doi.org/10.1017/S0266467416000493",
issn = "0266-4674",
language = "en",
targetfile = "cordeiro_impact.pdf",
urlaccessdate = "02 maio 2024"
}