Efeitos da riqueza de espécies e da diversidade filogenética no sucesso da restauração de uma floresta ripária

• Autor(a) principal: Moura, Janara Lisiany de Oliveira
• Data de Publicação: 2017
• Tipo de documento: Trabalho de conclusão de curso
• Idioma: por
• Título da fonte: Repositório Institucional da UFRN
• Texto Completo: https://repositorio.ufrn.br/handle/123456789/43334
• topic: Biodiversidade e funcionamento de ecossistemas; Biodiversity and ecosystem functioning; Crescimento de plantas; Plant growth; Experimento de restauração; Restoration experiment

Biological diversity is the resource in which all nations are exclusively dependent; it is the basis of the planet's health, which in turn is being strongly degraded, mainly by anthropogenic factors such habitat loss. The decrease of biological diversity has generated great concern in the scientific literature, requiring more studies aiming to understand how species loss affect ecosystem functioning. Numerous studies revealed the importance of plant diversity for ecosystem functioning but to date few studies evaluated ecosystem functioning of restored environments. Additionally, a small number of studies looked at how plant diversity affects restoration success in degraded areas. In order to evaluate the effects of species richness and phylogenetic diversity over survival and growth of nine native plant species, an experiment was carried out to restore the riparian vegetation of a perennial stream located at the municipality of Monte Alegre (NE, Brazil). Nine tree species were selected to set up the experiment using a phylogenetic tree containing 47 plant species (among trees and shrubs) that naturally occur in the surrounding area. As the phylogenetic tree had three main clades, three species of each clade were selected. Thus, the experiment was defined with five levels of diversity: (i) control treatment (bare soil), (ii) monoculture, (iii) three related species (from the same clade), (iv) three distant species (from different clades) and (v) polyculture (containing all nine plant species). The 96 experimental plots (12 x 10 m) were implemented on both margins of the stream. The experiment started in September 2015, with the planting of 1656 individuals, 184 individuals per plant species. Plant survival was monitored in October 2016 and May 2017. Plant height was monitored in April and October 2016. Plant survival was lower in May 2017 compared to October 2016. Plant height was higher in October 2016, but plant relative growth rate was lower from June to October 2016 compared to December 2015 to April 2016 due to the reduction in rainfall. Diversity treatments did not affect the plant survival. However, treatments with phylogenetically distant species had taller plants in the final measurement. These results indicate that the use of phylogenetically distant plant species may be more effective for restoring degraded riparian vegetation. Phylogenetic diversity may contributes to a higher production of plant biomass because differential use of resource by distantly related species reduce competition among them, increasing the chances of restoration success in degraded areas.