Browsing by Subject "introduced species"

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  • Pieterse, Arnold; Rytkönen, Mari; Hellsten, Seppo (Finnish Environment Institute, 2009)
    Reports of the Finnish Environment Institute 15/2009
  • Arteaga, Alba; Malumbres-Olarte, Jagoba; Gabriel, Rosalina; Ros-Prieto, Alejandra; Casimiro, Pedro; Sanchez, Ana Fuentes; Albergaria, Isabel S.; Borges, Paulo A. V. (2020)
    The aim of our study was to characterise and compare the richness and composition of endemic, native (non-endemic) and introduced arthropod assemblages of two Azorean Historic Gardens with contrasting plant species composition. We hypothesised that Faial Botanic Garden would hold higher arthropod diversity and abundance of native and endemic arthropod species due to its larger native plant community. Species were collected using several arthropod standardised techniques between April 2017 and June 2018. We used the alpha diversity metrics (Hill series) and the partitioning of total beta diversity (beta(total)) into its replacement (beta(repl)) and richness (beta(rich)) components, to analyse the adult and total arthropod community. The orders Araneae, Coleoptera and Hemiptera were also studied separately. Our results show that the number of exotic arthropod species exceeds the number of native and/or the endemic species in both gardens, but the arthropod community of Faial Botanic Garden exhibited a higher density of endemic and native species. Despite some minor exceptions, the geographic origins of plant communities largely influenced the arthropod species sampled in each garden. This study improves our knowledge about urban arthropod diversity in the Azores and shows how well-designed urban garden management and planning contribute to the conservation of native and endemic Azorean species.
  • Lehtonen, J.T.; Mustonen, O.; Ramiarinjanahary, H.; Niemelä, J.; Rita, H. (Kluwer Academic Publishers, 2001)
    We used logistic and Poisson regression models to determine factors of forest and landscape structure that influence the presence and abundance of rodent species in the rain forest of Ranomafana National Park in southeastern Madagascar. Rodents were collected using live-traps along a gradient of human disturbance. All five endemic rodent species (Nesomys rufus, N. audeberti, Eliurus tanala, E. minor and E. webbi) and the introduced rat Rattus rattus were captured in both secondary and primary forests, but the introduced Mus musculus was only trapped in secondary forest. The abundance of R. rattus increased with the level of habitat disturbance, and it was most common in the heavily logged secondary forest. Furthermore, the probability of the presence of R. rattus increased with decreasing distance from forest edge and decreasing canopy cover, while the probability of presence increased with increasing herbaceous cover, altitude and overstory tree height. The species was never observed farther than 500 m away from human habitation or camp-site. N. rufus prefered selectively-logged forest at altitudes above 900 m a.s.l. Its probability of presence increased with increasing canopy cover, herbaceous cover and distance from forest edge, and with decreasing density of fallen logs, overstory tree height and distance from human habitation. N. audeberti prefered heavily-logged areas, while E. tanala was the only species occurring along the entire range of forest disturbance. We suggest that in the Ranomafana National Park the spread of R. rattus is associated with deforestation.
  • Raateoja, Mika; Setälä, Outi (Finnish Environment Institute, 2016)
    Reports of the Finnish Environment Institute 27/2016
    This assessment on the environmental state of the Gulf of Finland in 1996 – 2014 was produced by together over 100 scientists from Estonia, Finland, and Russia in the context of the Gulf of Finland Year 2014. The thematic year aimed at – and succeeded in – giving additional value for the protection and restoration of the Gulf of Finland environment by enhancing political presence and interaction between the private sector, decision-makers, and citizens. This assessment concentrates on the past development and the current state of the Gulf of Finland environment and pressures affecting it. The themes include climate in the Gulf of Finland area, Gulf of Finland physics, geology and geodiversity, eutrophication, hazardous substances, biodiversity, fishes and fisheries, nonindigenous species, marine litter, underwater soundscape, maritime traffic and its safety, and environmental valuation. Each chapter also delivers expert opinions and recommendations for the future.