title: The introduced tree Prosopis juliflora is a serious threat to native species of the Brazilian Caatinga vegetation.
abstract: Despite its economic importance in the rural context, the Prosopis juliflora tree species has already invaded millions of hectares globally (particularly rangelands), threatening native biodiversity and rural sustainability. Here we examine seedling growth (leaf area, stem diameter, plant height) and seedling mortality across five native plant species of the Caatinga vegetation in response to competition with P. juliflora. Two sowing treatments with 10 replications were adopted within a factorial 2 × 5 randomized block design. Treatments consisted of P. juliflora seeds sowed with seeds of Caesalpinia ferrea, Caesalpinia microphylla, Erythrina velutina, Mimosa bimucronata and Mimosa tenuiflora (one single native species per treatment), while seeds of native species sowed without P. juliflora were adopted as controls. Overall, our results suggest that P. juliflora can reduce seedling growth by half and cause increased seedling mortality among woody plant species. Moreover, native species exhibit different levels of susceptibility to competition with P. juliflora, particularly in terms of plant growth. Such a superior competitive ability apparently permits P. juliflora to establish monospecific stands of adult trees, locally displacing native species or limiting their recruitment. The use of less sensitive species, such as C. ferrea and M. tenuiflora, to restore native vegetation before intensive colonization by P. juliflora should be investigated as an effective approach for avoiding its continuous spread across the Caatinga region.
authors.affiliation: Empresa Brasileira de Pesquisa Agropecuária, Centro de Pesquisa Agropecuária do Trópico Semi-Árido, 56300-970 Petrolina, Pernambuco, Brazil; Departamento de Ciências Humanas, Universidade do Estado da Bahia, 48900-000 Juazeiro, Bahia, Brazil.
authors.forename: Clóvis Eduardo
authors.initials: CE
authors.lastname: de Souza Nascimento
authors.affiliation: Departamento de Botânica, Universidade Federal de Pernambuco, 50670-901 Recife, Pernambuco, Brazil.
authors.forename: Marcelo
authors.initials: M
authors.lastname: Tabarelli
authors.affiliation: Empresa Brasileira de Pesquisa Agropecuária, Centro Nacional de Pesquisa de Algodão, 58428-095, Brazil; Programa de Pós-Graduação em Ciências Agrárias, Universidade Estadual da Paraíba, 58429-570 Campina Grande, Paraíba, Brazil.
authors.forename: Carlos Alberto Domingues
authors.initials: CA
authors.lastname: da Silva
authors.affiliation: Departamento de Botânica, Universidade Federal de Pernambuco, 50670-901 Recife, Pernambuco, Brazil.
authors.forename: Inara Roberta
authors.initials: IR
authors.lastname: Leal
authors.affiliation: Departamento de Fitotecnia, Universidade Federal de Viçosa, 36570-900 Viçosa, Minas Gerais, Brazil.
authors.forename: Wagner
authors.initials: W
authors.lastname: de Souza Tavares
authors.affiliation: Departamento de Biologia Geral, Universidade Federal de Viçosa, 36570-900 Viçosa, Minas Gerais, Brazil.
authors.forename: José Eduardo
authors.initials: JE
authors.lastname: Serrão
authors.affiliation: Departamento de Biologia Animal, Universidade Federal de Viçosa, 36570-900 Viçosa, Minas Gerais, Brazil. Electronic address: zanuncio@ufv.br.
authors.forename: José Cola
authors.initials: JC
authors.lastname: Zanuncio
mesh_terms: D044822:Biodiversity; D001938:Brazil; D003247:Conservation of Natural Resources; D017753:Ecosystem; D016468:Forestry; D058865:Introduced Species; D029862:Prosopis / Q000254:growth & development*
keywords: Biodiversity; Competition; Plant growth and mortality; Plant invasion