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9958782 
Journal Article 
Leafing patterns and leaf exchange strategies of a cerrado woody community 
Gutierrez de Camargo, MG; de Carvalho, GH; Alberton, BdeC; Reys, P; Cerdeira Morellato, LP 
2018 
Yes 
Biotropica
ISSN: 0006-3606
EISSN: 1744-7429 
50 
3 
442-454 
WOS:000433564900008 
The deciduousness of tropical trees and communities depend on ecosystems characteristics such as plant species diversity, and strength of the dry season. Based on seven years of phenological observations, we provide the first long-term description of leafing patterns of a woody cerrado community, aiming to investigate (1) the leaf exchange strategies considering the interannual variation in the degree of deciduousness of individuals and species and quantify the community deciduousness; (2) the relationship between interannual patterns of leaf fall and leaf flush according to the species" leaf exchange strategies and climate; (3) the onset of cerrado growing season and its relation to climate seasonality. To detect seasonality and leafing onset we applied circular statistics and to understand the relationships between environmental predictors and leaf exchange strategies, we used generalized additive models. From 106 species observed, we classified 69 as deciduous (26 species), semi-deciduous (25) or evergreen (18) and defined the studied cerrado as a semi-deciduous vegetation. Leaf phenology was markedly seasonal and similar among years. Leaf fall peaked in the dry season, and leaf flush in the dry-to-wet transition. Leaf fall patterns related to temperature and leaf flush to day length and rainfall. Semi-deciduous and deciduous species were more constrained by climate than the evergreen ones. The cerrado growing season started in the dry-to-wet season transition. Interannual variations in rainfall and temperature affected the individuals" and, consequently, species" degree of deciduousness, highlighting individual and species variability, and suggesting that cerrado leafing patterns are likely susceptible to future climate change scenarios. Resumo A deciduidade das arvores e comunidades tropicais depende de caracteristicas do ecossistema como a diversidade de especies de plantas e a intensidade da estacAo seca. Baseados em sete anos de observacoes fenologicas, apresentamos uma descricAo de longo prazo de padroes vegetativos de uma comunidade lenhosa de cerrado com o objetivo de investigar: (1) as estrategias de trocas foliares considerando a variacAo interanual no grau de deciduidade dos individuos e especies e quantificar a deciduidade da comunidade; (2) as relacoes entre padroes interanuais de queda e brotamento foliar conforme a estrategia de trocas foliares das especies e o clima; (3) o inicio da estacAo de crescimento da comunidade de cerrado estudada e sua relacAo com a sazonalidade climatica. Utilizamos estatistica circular para analisar a sazonalidade fenologica e o inicio do brotamento foliar na comunidade, e modelos aditivos generalizados para entender as relacoes entre variaveis ambientais e as estrategias de trocas foliares. Dentre as 106 especies observadas, 69 foram classificadas como deciduas (26 especies), semi-deciduas (25) ou sempre-verdes (18) e definimos o cerrado estudado como uma vegetacAo semi-decidua. A fenologia vegetativa foi marcadamente sazonal e similar entre anos. O pico de queda foliar ocorreu na estacAo seca e o de brotamento na transicAo entre as estacoes seca e chuvosa. O padrAo de queda de folhas foi relacionado a temperatura e o de brotamento ao comprimento do dia e pluviosidade. As especies deciduas e semi-deciduas foram mais afetadas pelo clima do que as sempre-verdes. A estacAo de crescimento no cerrado comecou na transicAo entre as estacoes seca e umida. As variacoes interanuais na precipitacAo e temperatura afetaram o grau de deciduidade de individuos e consequentemente das especies, ressaltando a alta variabilidade individual e especifica, sugerindo que os padroes de troca foliar das especies do cerrado podem ser afetados por mudancas climaticas futuras. 
climatic drivers; deciduous; evergreen; generalized additive models; leaf phenology; savanna; seasonality; semi-deciduous