Functional diversity of reproductive traits increases across succession in the Atlantic forest

Abstract

Niche and neutral processes shape community assembly with a possible shift of niche and neutral importance in communities undergoing temporal changes during succession. Functional diversity helps to discriminate assembly processes since trait distribution is dependent on those processes. We evaluated the changes in reproductive traits related to pollination and seed dispersal in a successional gradient in an Atlantic Forest area, Southern Brazil. We surveyed forests undergoing regeneration varying in age from 2 to 80 years after pasture abandonment. We expected an increase in functional diversity of reproductive traits and a greater role of limiting similarity across succession. Abiotic and mixed pollination systems, dioecious sexual system, biotic dispersed, many-seeded and small-seeded species decreased as the forest got older. Conversely, bee-pollinated, bell-shaped, small and androgynous flowers increased across forest succession as well biotic dispersed and large-seeded species. Functional richness and functional dispersion were higher in older forests. Changes in functional diversity were positively related to species richness, indicating that species enrichment in older forests added new sets of reproductive traits. These changes in trait distribution and functional diversity across succession in the Atlantic Forest suggest an increased role of biotic interactions and limiting similarity process structuring plant assemblages of second-growth tropical forests. Key words: dispersal, functional dispersion, pollination, forest regeneration, functional richness. ResumoAs florestas apresentam um enriquecimento gradual de espécies e um aumento em complexidade estrutural e funcional durante a sucessão. Este trabalho caracterizou os traços reprodutivos de plantas relacionados à polinização e à dispersão em um gradiente sucessional, em uma área de Mata Atlântica, Sul do Brasil. O levantamento das espécies foi realizado em áreas florestais sucessionais oriundas de regeneração natural, em idades variando entre 2 e 80 anos após o abandono da pastagem. Houve predominância de flores polinizadas por abelhas, abertas, hermafroditas e que disponibilizam o pólen como em todos estádios sucessionais. Os sistemas de polinização abiótico e misto, sistema sexual dióico, espécies com dispersão abiótica, com muitas sementes e sementes pequenas diminuíram com a idade das florestas. Espécies polinizadas por abelhas, flores com corola funil/sino, como de corola pequena e andróginas assim como espécies dispersas bioticamente e com sementes grandes aumentaram no gradiente sucessional. A riqueza funcional e a dispersão funcional aumentaram no gradiente sucessional. As mudanças da diversidade funcional foram relacionadas com o aumento da riqueza de espécies indicando que o enriquecimento de espécies em florestas mais velhas adicionou novos conjuntos de traços reprodutivos. Estas mudanças de distribuição de traços e de diversidade funcional no gradiente sucessional sugerem um incremento do papel de interações bióticas na estrutura...

Breeding system and pollination of Pleroma trichopodum DC. (Melastomataceae): a potential species for the restoration of Atlantic Forest in southern Brazil

“…1), which, until recently, was named Tibouchina trichopoda (Meyer et al 2010). Pleroma trichopodum is a pioneer tree adapted to environments saturated with water (Meyer et al 2010;Maia et al 2013), and is abundant in areas undergoing early natural regeneration in southern Brazil (Cardoso 2014;Warring et al 2016). Although it has potential for use in the restoration of Atlantic Forest, knowledge of its reproductive and pollination biology is incomplete, particularly regarding its pollinators and mating system.…”

Community structure and tree diversity in a subtropical forest in southern Brazil

“…These indexes indicated the balance of few dominant species and many species with lower abundance. This result reflects the ecological stability and maturity of the community (Wright 2007, Warring et al 2016. Table 2.…”

Functional importance of sacred forest patches in the altered landscape of Palakkad region, Kerala, India

“…The relatively higher value could be a result of homogeneous trait distribution indicating an apparent absence of habitat filtering or related mechanism (Warring et al . 2016). But, their high values in these small groves could also be an indicator of loss of functional redundancy and ecosystem resilience in the near future (Magnago et al .…”

“…2013, Warring et al . 2016). Moreover, availability of information and possibility of quantification were other determining factors for trait selection.…”