Landscapes Forest and Global Change - ESA - Escola Superior ...

I. Silva et al. 2010. Lisbon’s public gardens, host place for world’s trees
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• Class 4 Evenness Index (1 if [0-0,33]; 2 if [0,34-0,66]; 3 if [0,67-1])
• Average of Botanical Diversity Indices
ni : number of individuals in each species;
abundance of each species.
S : number of species (richness)
N : total number of all individuals:
p i : relative abundance of each species,
calculated as the proportion of individuals of
one species to the total number of individuals in
the community:
The Botanical Singularity score was based on the occurrence of one, two or three individuals of
a particular species in the set of gardens studied.
Singularity Evaluation Method:
• 3 – contains the only specimen of a species;
• 2 – contains one/two of the only two specimens of a species;
• 1 - contains one/two/three of the only three specimens of a species;
• 0 - if there are more than three specimens of a species
The characterization of 31 public gardens according to the defined indicators enabled the
acknowledgement of their social, historical and aesthetic features, and their ranking.
3. Result and discussion
A total of 3751 trees were recorded in the 31 gardens studied, and the following results
were obtained: 46 families, 83 genus and 139 different species, of which 58% are
evergreen and 42% deciduous. As regards their origin, 48% are exotic, 35% naturalized,
13% indigenous and 4% exotic invaders. The dominant species are Celtis australis,
Olea europaea var. sylvestris, Pinus pinea and Phoenix canariensis (see figure 1). The
following species stand out because of their singularity: Erythrina crista-gallis,
Firminiana simplex, Koelreuteria paniculata, Melaleuca stypheliodes and Pawlonia
tomentosa.
Figure 1 - Trees in Lisbon's Public Gardens
Forest Landscapes and Global Change-New Frontiers in Management, Conservation and Restoration. Proceedings of the IUFRO Landscape Ecology
Working Group International Conference, September 21-27, 2010, Bragança, Portugal. J.C. Azevedo, M. Feliciano, J. Castro & M.A. Pinto (eds.)
2010, Instituto Politécnico de Bragança, Bragança, Portugal.