J Plant Ecol ›› 2019, Vol. 12 ›› Issue (1): 186-198.DOI: 10.1093/jpe/rty009

• Research Articles • Previous Articles     Next Articles

Sharp differentiation on the performance of plant functional groups across natural edges

Evelyn da Fonseca Alecrim Bragion1,*, Gabriela Aparecida Oliveira Coelho1, Flávia Freire de Siqueira1, Maria Uriarte2 and Eduardo van den Berg1   

  1. 1Department of Forest Engineering, Federal University of Lavras, Campus Universitário, Caixa Postal 3037, CEP 37200-000, Lavras, MG, Brazil
    2Department of Ecology, Evolution and Environmental Biology, Columbia University, New York, NY, USA
    *Correspondence address. Department of Forest Engineering, Federal University of Lavras, Campus Universitário, Caixa Postal 3037, CEP 37200-000, Lavras, MG, Brazil. Tel: +55-35-99100-1017; E-mail: evelyn.alecrim@gmail.com
  • Received:2017-03-13 Revised:2017-12-28 Accepted:2018-02-12 Online:2018-02-14 Published:2019-02-01

Abstract:

Aims

Gallery forests within grasslands have natural edges with open environments and offer a unique opportunity to examine how species performances vary across environmental gradients. Here, we asked if demographic rates of tree functional groups varied along the edge, if we could explain differences in plant strategies and performance through functional traits and which traits increase growth and survival in natural edges.

Methods

We examine mortality and recruitment within the first 10 m of natural edges of eight gallery forests using demographic data from five annual inventories. We defined a priori plant strategies using tree functional groups: light demanding, pioneer and shade tolerant.

Important Findings

The shade-tolerant group had the lowest mortality rates and basal area (BA) loss, while pioneer and light-demanding species had similar behavior for these rates. The survival and growth of functional groups were affected differently by the distance from the edge. The pioneer group survived more near the edge, while light-demanding and shade-tolerant groups toward the forest interior. All groups had higher growth in the grassland. Those differences could be explained by functional traits since most species have an acquisition strategy: higher specific leaf area and growth, lower leaf dry matter content, lighter stem density, deeper crowns and less slender stems. Acquisitive traits enhanced growth. However, mortality selected both strategies, but in distinct edge’s zones. Our study showed that the high diversity found in natural edges can be explained by a niche and functional perspective, where differences in functional traits lead to differential performance along the environmental gradient.

Key words: edges diversity, gradient, niche hypothesis, SLA, LDMC