Biodiversity in the Argentinean Rolling Pampa Ecoregion: changes cuased by agriculture and urbanisation

FAGGI, A.M.; KRELLENBERG,K; CASTRO, R.; ARRIAGA, M.O.; ENDLICHER, W.

Urban Ecology

Springer

Lugar: New York, USA; Año: 2008; p. 377 - 389

The metropolitan area of Buenos Aires is located in the rolling pampa, one of the most productive ecoregions of the world (44.000 km2, 33º S and 39º S). This region has undergone deep transformations caused by agricultural, residential, industrial and commercial land-uses. The purpose of this paper is to compare to what extent plant and bird richness are influenced by urban and agricultural uses. To capture the land-use effects a comparison along an urbanisation gradient was made. Green spaces and farmland, located in areas of contrasting land-use, extending from the La Plata's rivershore to semirural and rural areas, were sampled. Some untuchable areas and past century biodiversity census were also included in the study in order to contrast the results. At the community level vascular plant richness, floristic composition and bird presence were considered. To compare the different sites along the gradient biodiversity indexes and Sørensen's coefficient of similarity were calculated. At the landscape level the percentage of forest, grassland, shrubland, wetland and rivers/streams was measured. The data were correlated using Principal Components Analysis (PCA). In general, the decrease of native plants and bird richness towards the city centre is consistent with the studies of other cities. The results of the present study confirm that the actual cultivation practices are extremely more dangerous for conservation of native land than urban sprawl. than urban sprawl.