Resistance to fire and the resilience of the woody vegetation of the “Cerradão” in the “Cerrado”–Amazon transition zone

Abstract

The savanna formations of the Brazilian ''Cerrado'' present a high degree of resistance and resilience to the impacts of fire, although little is known of its forest formations. Given this, the present study evaluated the resistance and resilience of the ''Cerradão'' to fire impacts over a 7-year period. In March 2008, we established 50 permanent plots of 10 m 9 10 m and measured all the woody individuals with a base diameter C5 cm. Six months later, all plots were burned by an accidental fire. In March 2012 and March 2015, we re-measured all surviving individuals, and measured the recruits. Species richness, the density of individuals, and the basal area were all significantly greater (P \ 0.05) in 2008, prior to the fire, in comparison with 2012 and 2015, after the fire. Species richness and the density of individuals were also higher (P \ 0.05) in 2015, about 7 years post-fire, in comparison with 2012. During the interval in which the fire occurred (2008-2012), the mortality and reposition time, and the stability were all higher (P \ 0.05) than during the subsequent interval, post-fire (2012-2015). The recruitment rate was also lower between 2008 and 2012 (P \ 0.05). Our results indicate that the ''Cerradão'' has reduced resistance and resilience to the disturbances caused by fire relative to savanna formations. Given this, frequent burn-off may cause drastic alterations to this phytophysiognomy, emphasizing the need for special care for the preservation of its biodiversity. Keywords Conservation Á Dynamics Á Fires Á Forest formations Á Mortality Á Structural and floristic changes Electronic supplementary material The online version of this article (

Coleção Botânica De Plantas Medicinais: Um Álbum Como Proposta Didática No Ensino De Biologia Vegetal

“…A transição Amazônia-Cerrado apresenta vegetação única e complexa com várias formações que apresentam dinâmica mais rápida do que as do interior da Floresta Amazônica e Cerrado (MARIMON et al, 2014). Dessa forma, a heterogeneidade dessa transição (MORANDI et al, 2015;OLIVEIRA et al, 2017;PEIXOTO et al, 2017;REIS et al, 2017;PEIXOTO et al, 2018) pode contribuir para ocasionar maior oscilação do efluxo de gás carbônico em função dos aspectos da paisagem.…”

Botânica: melhoramento, conservação e produção

“…A transição Amazônia-Cerrado apresenta vegetação única e complexa com várias formações que apresentam dinâmica mais rápida do que as do interior da Floresta Amazônica e Cerrado (MARIMON et al, 2014). Dessa forma, a heterogeneidade dessa transição (MORANDI et al, 2015;OLIVEIRA et al, 2017;PEIXOTO et al, 2017;REIS et al, 2017;PEIXOTO et al, 2018) pode contribuir para ocasionar maior oscilação do efluxo de gás carbônico em função dos aspectos da paisagem.…”

Intraspecific trait variability facilitates tree species persistence along riparian forest edges in Southern Amazonia

“…Although conservative strategies typically characterize primary tropical forests, increased anthropogenic disturbances may cause tree communities to adopt more acquisitive strategies 9 owing to changes in light and resource availability (e.g., water and nutrients) 31 , 32 . These alterations in functional strategies can be caused by the increased dominance of pioneer species 33 , which have fast growth, high mortality and recruitment rates, and a short lifespan. For example, in riparian forests in the transition zone between the Cerrado and Amazonia, Tachigali vulgaris is a colonizing generalist that recruits at a high rate and is abundant in forest gaps or burned forests 33 , 34 .…”

“…These alterations in functional strategies can be caused by the increased dominance of pioneer species 33 , which have fast growth, high mortality and recruitment rates, and a short lifespan. For example, in riparian forests in the transition zone between the Cerrado and Amazonia, Tachigali vulgaris is a colonizing generalist that recruits at a high rate and is abundant in forest gaps or burned forests 33 , 34 . Changes in functional strategies can also result from the increased dominance of generalist species, which can have high intraspecific variability that allows them to thrive in a wide range of environmental conditions.…”