Distribution of non-native invasive species and soil properties in proximity to paved roads and unpaved roads in a quartzitic mountainous grassland of southeastern Brazil (rupestrian fields)

Abstract

One of the most important disturbances of roads is the facilitation of the increase of non-native invasive species into adjacent plant communities. The rupestrian fields of Serra do Cipo´, a montane grassland ecosystem in southeastern Brazil, are recognized for their enormous richness of species and endemism rates. The presence of non-native invasive species in this ecosystem could threaten the existence of the native flora and its associated organisms. The aim of this study is to understand how non-native invasive species and native species are distributed along paved and unpaved roads, in a montaneous grassland ecosystem such as the Brazilian rupestrian fields. The two road surfaces provide differing gradients from their edges with respect to nutrients, soil chemical aspects and plant species diversity. High content of calcium at the roadside in the paved road resulted from the paving process, in which limestone gravel is used in one of the several paving phases. In these newly created habitats the toxicity of aluminum is drastically reduced and nutrient enriched, hence representing favorable sites from where non-native invasive species are capable to colonize and grow for undetermined period waiting the chance to invade the adjacent pristine habitats. Disturbances provoked by any natural or humancaused event can provide the opportunity for the nonnative invasive species to colonize new plant communities.

Fenologia reprodutiva, sazonalidade e germinação de Kielmeyera regalis Saddi (Clusiaceae), espécie endêmica dos campos rupestres da Cadeia do Espinhaço, Brasil

“…Estudos sobre fases posteriores à germinação em campo serão necessários para se elucidar sobre a ocorrência de estratégias similares nesta espécie.As estratégias relacionadas ao recrutamento devem ser compreendidas uma vez que são mecanismos fundamentais de declínio, persistência e expansão de espécies em paisagens em processo de alteração. Os resultados gerados neste estudo são importantes para a compreensão básica dos fatores limitantes ao crescimento e manutenção das populações de Kielmeyera regalis nos campos rupestres da Serra do Cipó, uma região em rápido processo de alteração (Barbosa et al 2010). Portanto, as estratégias de manejo e conservação de K. regalis nesse ecossistema ameaçado, como ações de propagação, resgate e reintrodução, devem considerar os padrões sazonais de fenologia e germinação observados para a espécie, reconhecendo o início da fase reprodutiva no período quente e úmido, dispersão das sementes após a estação seca e germinação no período chuvoso.…”

Vegetation composition and structure of some Neotropical mountain grasslands in Brazil

“…gold, precious stones, iron, manganese) in the region. Nowadays degradations are also associated to an increase in uncontrolled anthropogenic burnings and in fire frequency (while natural fires are a rare event, farmers burn grasslands annually to stimulate grass regrowth in order to support cattle breeding), wood extraction, eucalyptus plantation, harvesting of ornamental plants (orchids, bromeliads, Eriocaulaceae) (Giulietti et al 1997), and road construction (Barbosa et al 2010). While threats increase, limited data on conservation targets, such as plant communities (Heywood and Iriondo 2003), hamper the conservation and the restoration of these campos rupestres.…”

Minor rural road networks: values, challenges, and opportunities for biodiversity conservation

“…Owing to their linear configuration and connectivity to other habitats, minor roads are often been blamed for acting as conduits for plant invasions (e.g. Gelbard and Belnap 2003, Dark 2004, Pauchard and Alaback 2004, Kalwij et al 2008, Barbosa et al 2010, Brisson et al 2010. Many species can disperse over long distances throughout human modified landscapes because roads create continuous habitat over many kilometres (Christen and Matlack 2006).…”

“…The extent to which minor roads provide biodiversity conservation benefits for species, as opposed to promoting alien flora and fauna, is largely dependent past landuse history and ongoing disturbances experienced in roadsides , Hansen and Clevenger 2005, Barbosa et al 2010. The maintenance of minor roads can alter soils, light levels, dust, patterns of water runoff and sedimentation, and introduce nutrients and other pollutants to adjacent roadside environments (Gelbard andBelnap 2003, Trombulak andFrissell 2000).…”