Does plant architectural complexity increase with increasing habitat complexity? a test with a pioneer shrub in the Brazilian Cerrado [A complexidade arquitetural de plantas aumenta com a complexidade do habitat? um teste com um arbusto pioneiro de Cerrado]
Silveira F.A.O.,Federal University of Minas Gerais |
Oliveira E.G.,Centro Universitario Una
Brazilian Journal of Biology | Year: 2013
Understanding variation in plant traits in heterogeneous habitats is important to predict responses to changing environments, but trait-environment associations are poorly known along ecological gradients. We tested the hypothesis that plant architectural complexity increases with habitat complexity along a soil fertility gradient in a Cerrado (Neotropical savanna) area in southeastern Brazil. Plant architecture and productivity (estimated as the total number of healthy infructescences) of Miconia albicans (SW.) Triana were examined in three types of vegetation which together form a natural gradient of increasing soil fertility, tree density and canopy cover: grasslands (campo sujo, CS), shrublands (cerrado sensu strico, CE) and woodlands (cerradão, CD). As expected, plants growing at the CS were shorter and had a lower branching pattern, whereas plants at the CD were the tallest. Unexpectedly, however, CD plants did not show higher architectural complexity compared to CE plants. Higher architectural similarity between CE and CD plants compared to similarity between CS and CE plants suggests reduced expression of functional architectural traits under shade. Plants growing at the CE produced more quaternary shoots, leading to a larger number of infructescences. This higher plant productivity in CE indicates that trait variation in ecological gradients is more complex than previously thought. Nematode-induced galls accounted for fruit destruction in 76.5% infructescences across physiognomies, but percentage of attack was poorly related to architectural variables. Our data suggest shade-induced limitation in M. albicans architecture, and point to complex phenotypic variation in heterogeneous habitats in Neotropical savannas.
Ashton L.A.,Griffith University |
Ashton L.A.,CAS Xishuangbanna Tropical Botanical Garden |
Nakamura A.,Griffith University |
Nakamura A.,CAS Xishuangbanna Tropical Botanical Garden |
And 21 more authors.
Journal of Biogeography | Year: 2016
Aim: There is little consensus as to whether stratification of arthropods between canopy and understorey in tropical and subtropical forests is commonplace and if the magnitude of stratification changes across different elevations and latitudes. We investigated broad-scale patterns of vertical stratification of moths collected from extensive cross-continental fieldwork in a variety of forest types, climates, elevations, latitudes and areas with differing biogeographical history. Location: Tropical and subtropical rain forest in eastern Australia; tropical, subtropical and subalpine forest in Yunnan Province, China; and tropical rain forest in Panama, Vietnam, Brunei and Papua New Guinea. Methods: Night-flying moths were trapped from the upper canopy and understorey. We generated a total of 64 data sets to quantify vertical stratification of moths in terms of their species richness, using coverage-based rarefaction, and assemblage composition, using standardized hierarchical beta diversity. Based on the average temperature lapse rate, we incorporated latitudinal differences into elevation and generated 'corrected' elevation for each location, and analysed its relationships with the magnitude of stratification. Results: We found consistent differences between canopy and understorey assemblages at almost all rain forest locations across corrected elevational gradients. The magnitude of vertical stratification in species richness did not change with increasing corrected elevation. In contrast, the difference in assemblage composition increased with increasing corrected elevation in the Northern Hemisphere, while the opposite, albeit weak, trend was found in the Southern Hemisphere. Main conclusions: Clear vertical stratification was evident in moth assemblages regardless of elevation and latitude. However, the degree to which assemblages are stratified between canopy and understorey is not uniformly related to elevation and latitude. Inconsistencies in the magnitude of vertical stratification between the Northern and Southern Hemisphere, may reflect, on one hand, deep-time biogeographical differences between the land masses studied and, on the other, place-to-place differences in resource availability underpinning the observed moth assemblages. © 2016 John Wiley & Sons Ltd.
Lima M.H.C.,Centro Universitario Una |
Oliveira E.G.,Centro Universitario Una |
Silveira F.A.O.,Centro Universitario Una |
Silveira F.A.O.,Federal University of Minas Gerais
Biotropica | Year: 2013
The aim of this study was to evaluate the role of ants as secondary seed dispersers of six primarily bird-dispersed Miconia species in the cerrados of southeastern Brazil. Vertebrate exclosure and seed germination experiments were performed for M. albicans, M. alborufescens, M. corallina, M. ferruginata, M. ibaguensis, and M. irwinii. Excluding vertebrates did not significantly alter fruit removal rate for any of the Miconia species relative to open controls. Fruits on stalks and fallen fruits were removed and transported to nests mainly by species of Atta, Acromyrmex, and Ectatomma (dispersal distance ranging from 0.1 to 45.2 m), while Camponotus ants tended to be observed removing the fruit pulp (seed cleaning) where the fruits were found. Seed manipulation by Atta decreased germination of M. irwinii, but not M. ferruginata. Germination did not occur in intact fruits, and thus seed cleaning was an important service provided by the ants. Ant nest soils did not inhibit germination of any of the Miconia species, suggesting they are a good substrate for long-lived Miconia seeds. We conclude that ant activity could have important effects on the fate of Miconia seeds adapted for bird dispersal. © 2012 by The Association for Tropical Biology and Conservation.
The importance of bioprospecting of microorganisms in areas contaminated by petroleum-derived products [A importância da bioprospecção de microrganismos em áreas contaminadas com produtos derivados do petróleo]
Brito G.C.B.,Centro Universitario Una |
De Souza D.B.,Centro Universitario Una |
Vasconcelos F.C.W.,Doutora em Ciencias |
Da Conceicao Braga L.,Biologa
Revista em Agronegocio e Meio Ambiente | Year: 2010
The remarkable contribution of the oil sector to world economy leads to a demand that requires more structuring of the sector's production. Concerns related to environmental contamination possibility by petroleum products are on the increase. Pollution of soil, fresh water sources and sea environments caused by petroleum hydrocarbons causes severe problems to human, animal and vegetation health. Current bibliographical revision presents the characteristics of these pollutants, the processes involved in soil contamination, with special reference to biodegradation mechanism, and the bioprospecting of microorganisms capable of such processes. Degrading petroleum hydrocarbons is the property of several microorganism groups. The biological process of remediation, known as bioremediation, is caused by a stimulus in the environment's natural biodegradation. Bioprospecting of naturally selected organisms in areas contaminated by petroleum-derived substances represents an important strategy for the areas' bioremediation.
Basset Y.,Smithsonian Tropical Research Institute |
Basset Y.,University of South Bohemia |
Basset Y.,University of Panama |
Cizek L.,Academy of Sciences of the Czech Republic |
And 32 more authors.
PLoS ONE | Year: 2015
Quantifying the spatio-temporal distribution of arthropods in tropical rainforests represents a first step towards scrutinizing the global distribution of biodiversity on Earth. To date most studies have focused on narrow taxonomic groups or lack a design that allows partitioning of the components of diversity. Here, we consider an exceptionally large dataset (113,952 individuals representing 5,858 species), obtained from the San Lorenzo forest in Panama, where the phylogenetic breadth of arthropod taxa was surveyed using 14 protocols targeting the soil, litter, understory, lower and upper canopy habitats, replicated across seasons in 2003 and 2004. This dataset is used to explore the relative influence of horizontal, vertical and seasonal drivers of arthropod distribution in this forest. We considered arthropod abundance, observed and estimated species richness, additive decomposition of species richness, multiplicative partitioning of species diversity, variation in species composition, species turnover and guild structure as components of diversity. At the scale of our study (2km of distance, 40m in height and 400 days), the effects related to the vertical and seasonal dimensions were most important. Most adult arthropods were collected from the soil/litter or the upper canopy and species richness was highest in the canopy. We compared the distribution of arthropods and trees within our study system. Effects related to the seasonal dimension were stronger for arthropods than for trees. We conclude that: (1) models of beta diversity developed for tropical trees are unlikely to be applicable to tropical arthropods; (2) it is imperative that estimates of global biodiversity derived from mass collecting of arthropods in tropical rainforests embrace the strong vertical and seasonal partitioning observed here; and (3) given the high species turnover observed between seasons, global climate change may have severe consequences for rainforest arthropods. © 2015, Public Library of Science. All rights reserved. This is an open access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.