Análisis de la vegetación herbácea no gramínea y su relación con el banco de semillas en dos espacios verdes de la ciudad de La Plata, Argentina

Abstract

Urban green areas are under intense anthropogenic influence and often include a high proportion of native and/or exotic species, intentionally and/or accidentally introduced. The aim of this paper is to analyze and compare two green areas in La Plata city: a) the specific richness of non-grass herbaceous vegetation in association with grass lawns; b) the diversity and composition (qualitative and quantitative) of the soil seed bank; c) correspondence between aerial vegetation and seed bank. The analized sites were Parque Alberti and a sector of Paseo del Bosque of the city. Plants were collected from the aerial community and soil samples along transects, in four different seasons. Removal of seeds from soil samples was performed using the washing technique. There were a total of 37 species collected in 33 genera and 15 families, of which 15 species and 8 families were common to both studied areas. The qualitative similarity between the studied areas was medium (SI = 0.57) and quantitative between seed banks was low (MI = 0.36). The Paseo del Bosque sector showed the greatest wealth of aerial flora species and a high proportion of native species while the corresponding seed bank showed the highest values of floristic richness indices (R = 0.51), diversity (H ‘= 2.17) and evenness (J’ = 0.63), these observations indicate a lower frequency and intensity of disturbances in comparison with the Parque Alberti.

Urban green areas are under intense anthropogenic influence and often include a high proportion of native and/or exotic species, intentionally and/or accidentally introduced. The aim of this paper is to analyze and compare two green areas in La Plata city: a) the specific richness of non-grass herbaceous vegetation in association with grass lawns; b) the diversity and composition (qualitative and quantitative) of the soil seed bank; c) correspondence between aerial vegetation and seed bank. The analized sites were Parque Alberti and a sector of Paseo del Bosque of the city. Plants were collected from the aerial community and soil samples along transects, in four different seasons. Removal of seeds from soil samples was performed using the washing technique. There were a total of 37 species collected in 33 genera and 15 families, of which 15 species and 8 families were common to both studied areas. The qualitative similarity between the studied areas was medium (SI = 0.57) and quantitative between seed banks was low (MI = 0.36). The Paseo del Bosque sector showed the greatest wealth of aerial flora species and a high proportion of native species while the corresponding seed bank showed the highest values of floristic richness indices (R = 0.51), diversity (H '= 2.17) and evenness (J' = 0.63), these observations indicate a lower frequency and intensity of disturbances in comparison with the Parque Alberti.