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African sharptooth catfish Clarias gariepinus is native to most of Africa and small parts of Asia, but has been introduced to 37 countries mainly for aquaculture. This review of introductions, establishment, spread and impact of C. gariepinus in Brazil and outside of its native range in South Africa provides evidence that the species has been able to overcome all barriers to invasion in both countries. Following initial introductions across geographical barriers, containment seems to have been impossible and escape from aquaculture facilities and spread by illegal introductions is an invasion pathway in both countries. There is evidence of individuals dispersing rapidly following escape, and surviving and reproducing at multiple sites in a wide spectrum of habitats in both countries. There is a severe paucity of research on impacts, many of which are inferred from field and laboratory observations, but have not been demonstrated at population or community level. Such impact studies are urgently required to better understand the consequences of these invasions and to develop appropriate strategies to mitigate impacts and spread., (© 2016 The Fisheries Society of the British Isles.)

Non-native tree plantations represent 7% of the world's forests and 1.24% of the Brazilian vegetation. Planted areas are expected to increase in the near future; thus, it is important to systematize existing knowledge on the ecological effects of plantations to aid forest management and biodiversity conservation. Here, we conducted a systematic review of the ecological literature associated with planted Pinus and Eucalyptus species in Brazil. We compared publication metrics with geographical distribution of species, ecosystems, biomes, studied taxa, and ecological impacts. We found 152 publications from 1992 to 2012. Number of publications positively correlated with area planted, number of plantations with forest certification, number of researchers, and richness of studied kingdoms. Most studies were in terrestrial ecosystems (92.1%), the Atlantic Forest biome (55.3%), and the kingdom Animalia (68.2%). Most impacts of non-native tree plantations were negative (55.9%), followed by positive (27%), and mixed (17.1%). Negative impacts were declines in species richness and abundance, seed bank diversity, and natural regeneration. Positive impacts were increase or mainteinance of seed bank diversity and natural regeneration. Mixed impacts were increases in abundance of native tree plantation pests. Taken together, results suggest forest management can help maintain biodiversity if it considers previous environmental conditions and integrates plantations with surrounding habitats.