MACNBR   00242
MUSEO ARGENTINO DE CIENCIAS NATURALES "BERNARDINO RIVADAVIA"
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Urban Ecology and Integrated Coastal Management in Latin American cities: Some examples in the South Atlantic
Autor/es:
FAGGI A
Reunión:
Congreso; Congress of the Society for Urban Ecology (SURE); 2013
Resumen:
The complexity of the environmental management of touristic coastal cities depends on numerous factors related to own ecological processes in the coastal areas and uses and predominant activities. In the framework of the integrated coastal management the growth of the city must include a proper planning of the development that includes a conscious management of resources by avoiding chronic environmental problems. What factors determine forms of growth? What relationship has the consolidation of the urban area with natural areas and surrounding rural?; all questions that find answer in the Urban Ecology. This presentation discusses, taking as example argentine tourist resorts in the South Atlantic, how the urban linear pattern growth along the line of the coast and the union with other similar neighboring settlements is unsustainable and pose difficulties for environmental management. In particular, this study focus on urban green studying the human impact on the vegetation of several beaches located along a strip of Argentina?s Atlantic coast. It analyses temporal and spatial changes in the floristic composition of fore dune vegetation caused by urban development and human activities related to tourism along a transect parallel to the coastline. Four sampling stations were set at the centre (0 km), 2 km, 5 km and 10 km away from the beginning of the transect where ninety inventories at 38 sampling sites were made. Results show that the floristic similarity between the vegetation from the dunes farthest from urban centres and those closest to them was low (Sorensen index (SI) = 0.21). On the contrary, the comparison of the current floristic composition of the dunes with the past composition (early XX century) showed high similarity (Sorensen index = 0.60) between plant assemblages. In the case of dune obligate species we found very high similarity between dunes close to the urban centre and those away from it, for both natives (SI = 0.86) and the only exotic species recorded in that class: Cakile maritima (SI = 1). However, in the case of immigrant plants, the dunes and urban beaches had totally dissimilar assemblages of both natives (SI = 0.086) and exotics (SI = 0.21). Our research showed that tourism has been the main driving force of changes in plant composition in town resorts located along the northern Atlantic beaches of Argentina. Plant homogenisation has been the outcome of the loss of sensitive dune plants and changes in plant assemblages due to the gain of immigrant species. In city cores and adjacent areas, new man-made microhabitats encouraged non-native plants to displace most of the native assemblages during the urban growth process. Away from centers, vegetation composition was the same as past communities. Eutrophication and Urban green affected the distribution and abundance of indicator species. Both belong to the factors: favourable ?habitat? for establishment and ?transportation?- importation of exotics- that Mc Kinney (2006) singled out as the real causes of regularly observed biological patterns in cities. Finally, our study highlights the importance of giving due consideration to the conservation of native biodiversity when planning new resorts along the beach; e.g. by leaving the distances between neighbouring resorts long enough to guarantee the persistence of natural communities.