Time filter

Source Type

Fabricante J.R.,Federal University of Vale do Sao Francisco | Ziller S.R.,Instituto Horus Of Desenvolvimento E Conservacao Ambiental | de Araujo K.C.T.,Federal University of Vale do Sao Francisco | Furtado M.D.G.,Federal University of Vale do Sao Francisco | Basso F.A.,Federal University of Vale do Sao Francisco
Check List | Year: 2015

This paper is the result of a survey of the alien flora present on fluvial islands in the São Francisco River, northeastern Brazil. The floristic similarities between the islands wereassessed, as well as the relationship between area size and species richness. The study covered eight islands in the São Francisco River Valley and was carried out in a period of eight months. Thirty one alien species were registered, six of them (Amaranthus viridis, Calotropis procera, Cenchrus ciliaris, Enneapogon cenchroides, Prosopis pallida and Ricinus communis) present on all islands. The highest number of invasive alien species (26) was recorded on Massangano Island. The floristic similarity between the islands varied between medium and very high, while the number of alien species present was positively correlated with area size. The study demonstrates that the biodiversity on these eight fluvial islands is endangered, especially due to the presence of alien species capable of invading natural areas. © 2015 Check List and Authors.

Zenni R.D.,Instituto Horus Of Desenvolvimento E Conservacao Ambiental | Ziller S.R.,Instituto Horus Of Desenvolvimento E Conservacao Ambiental
Floresta | Year: 2011

Invasive alien species are introduced from other ecosystems and establish, producing viable descendency that spread for significant distances from the mother plants, potentially cause damage to the environment. The aim of the current study is to evaluate the first responses of the invasion process and the results of Pinus taeda control on three mountain areas in the Pico Paraná State Park, Southern Brazil. The control was conducted mechanically by felling adult trees and pulling out seedlings. The first responses were measured ten months after felling, measuring plant coverage and species richness. Results indicate that the population of invasive pines in these areas is around 36 years old, growing at a slower rate when compared to the average growth in other habitats, that the pine trees impact the native vegetation by producing lower coverage and finally, that after felling the pine trees the native vegetation showed lower richness. The control method had a cost of R$ 199,00 (about US$ 100) per hectare. Conclusions are that high mountain grasslands are susceptible habitats for biological invasion by pine trees and that recurrent work needs to be done for more consistent elucidations.

Zenni R.D.,Instituto Horus Of Desenvolvimento E Conservacao Ambiental | Ziller R.S.,Instituto Horus Of Desenvolvimento E Conservacao Ambiental
Revista Brasileira de Botanica | Year: 2011

Alien plants are known to occur in Brazil since the 18 th century when African grasses started to be recorded in pastures near Rio de Janeiro. In the beginning of the 19 th century two royal decrees (July, 1809 and July, 1810) offered grants and tax exemption to everyone who would introduce plants of economic value. Nowadays, there are 117 plant species recognized as invasive or established and with invasive potential in Brazil and an unknown number of introduced plant species. Some of the most pervasive invasive species are Artocarpus heterophyllus Lam. and Hedychium coronarium Konig in tropical ombrophilous forest, Hovenia dulcis Thunb. in subtropical ombrophilous forest and subtropical semi-deciduous forest, Pinus taeda L. and Pinus elliottii Engelm. in subtropical ombrophilous forest and steppe, Prosopis juliflora (Sw.) DC. in stepic-savanna, Tecoma stans (L.) Juss. ex Kunth in tropical and subtropical semi-deciduous forest, Melinis minutiflora P. Beauv. in the Brazilian savannas, and Eragrostis plana Nees in the steppe. The purpose of this article is to fill a knowledge gap on alien species that are invasive in Brazil and where they are invading by summarizing data obtained by joint efforts of the Horus Institute for Environmental Conservation and Development, The Nature Conservancy (TNC), the Inter-American Biodiversity Information Network (IABIN) invasive species thematic network (I3N), and the Brazilian Ministry of Environment (MMA) in the last six years.

Discover hidden collaborations