Similaridade Florística Entre Trechos De Floresta Estacional Semidecidual Do Corredor De Biodiversidade Santa Maria - Pr

Abstract

RESUMOOs Corredores de Biodiversidade têm a função de manter e restabelecer a conectividade entre fragmentos florestais remanescentes. O Corredor de Biodiversidade Santa Maria -PR visa conectar o Parque Nacional do Iguaçu à mata ciliar do reservatório de Itaipu, através da implantação de áreas de reflorestamento entre fragmentos remanescentes de Floresta Estacional Semidecidual. Este trabalho objetivou avaliar a diversidade de espécies arbóreas e a similaridade florística entre áreas de florestas nativas secundárias e de reflorestamentos em diferentes idades. Compararam-se a densidade, a diversidade, a equabilidade e a composição florística dos cinco fragmentos e a similaridade foi avaliada pelos índices de Jaccard e de distância de Bray-Curtis. Em dois hectares amostrados, foram encontrados 2328 indivíduos, distribuídos em 134 espécies e 39 famílias. A similaridade florística agrupou as florestas secundárias nativas mais preservadas e as áreas com reflorestamento em grupos distintos. As 11 espécies exóticas encontradas nas áreas de reflorestamento não foram observadas nas áreas mais preservadas e, portanto, o manejo das mesmas deve ser incentivado, como medida de preservação dos fragmentos nativos remanescentes de Floresta Estacional Semidecidual. Palavras-chave: Mata Atlântica; fragmentação. ABSTRACTThe function of Biodiversity Corridors is to maintain and restore connectivity between forest fragments remains. Santa Maria Biodiversity Corridor, in PR state, aims to connect Iguaçu National Park to the riparian forest of the Itaipu reservoir, through the implementation of reforestation areas between remnants of Seasonal Semidecidual Forest. This study aimed to evaluate the diversity of tree species and the floristic similarity between the areas of native secondary forests and reforested areas of different ages. There were compared the density values, diversity, evenness, and floristic composition from five study areas, and the similarity was evaluated by Jaccard and Bray-Curtis distance. In two hectares, we found 2,328 individuals of 134 species and 39 families. The floristic similarity grouped the native secondary forests, which are best preserved, and the reforested areas in different groups. The 11 exotic species found in reforested areas were not observed in the most preserved areas. So, the managament of them should be encouraged in order to protect the remaining Seasonal Semidecidual Forest.

Comparing the potential reproductive phenology between restored areas and native tropical forest fragments in Southeastern Brazil

“…Our results showed that similarity in species composition varied among sites in the studied areas. The low degree of similarity we found among forest fragments sites has been reported in other studies from tropical forests (Norden et al 2015;Arroyo-Rodríguez et al 2017) and could be due to differences in rainfall, temperature, climate seasonality, and soil characteristics (Cottenie 2005), as these factors affect species distribution and could also alter phenological patterns of species (Oliveira-Filho et al 2001;Gris & Temponi 2017). In addition, disturbance history is also an important factor affecting the successional trajectory of plant communities (Arroyo-Rodríguez et al 2017).…”

Effect of slope on the forest structure of the Atlantic Forest domain in southern Brazil

“…One of the phytophysiognomies comprising this domain is the Seasonal Semideciduous Forest that originally covered 37.7% territory of the state of Paraná. However, it has been drastically reduced, and is currently a threatened and fragmented phytophysiognomy with only 3.4% native vegetation (Gris and Temponi, 2017). The major causes of the degradation of this phytophysiognomy are due to monocultures and selective logging in the state of Paraná (Rodrigues et al, 2016;Dettke et al, 2018).…”

Thinning enhances success of enrichment planting with selected tree species under a pure stand of Leucaena leucocephala

“…The species has been considered invasive in many parts of the world (Yoshida & Oka 2004; Costa et al 2015; Luo et al 2020 and others), included among the 100 most aggressive invasive species on the planet by the World Conservation Union (IUCN) (Lowe et al 2000). However, leucaena has been shown to be rather a dominant weed occupying cleared land than a true invader colonizing natural undisturbed ecosystems and displacing native species (Costa & Durigan 2010; Richardson 2011; Gris & Temponi 2017). As a dominant weed, leucaena often forms dense homogeneous stands, hindering colonization of the understory by native seedlings (Mello & Oliveira 2016).…”