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- The coastal vegetation of the portuguese Divisory Sector: dunes, cliffs, saltmarshes and low-scrub communitiesPublication . Costa, José Carlos; Lousã, M.; Capelo, J.; Espírito-Santo, Maria Dalila; Izco, J.; Arsénio, Pedro
- A methodological approach to potential vegetation modeling using GIS techniques and phytosociological expert-knowledge: application to mainland PortugalPublication . Capelo, J.; Mesquita, S.; Costa, José Carlos; Arsénio, Pedro; Neto, C.; Monteiro-Henriques, T.; Aguiar, C.; Honrado, J.; Espírito-Santo, Maria Dalila; Lousã, M.An attempt to obtain a consistent spatial model of natural potential vegetation (NPV) for the mainland Portuguese territory is reported. Spatial modeling procedures performed in a Geographic Information System (GIS) environment, aimed to operationalize phytosociological expert-knowledge about the putative distribution of potential zona1 forest communities dominam in the Portuguese continental territories. The paradigm for NPV assumed was that of RIVAS-MARTINE(1Z9 76) and RIVAS-MARTINEeZt al. (1999), which presupposes, for a given territory, a univocal correspondence between a uniform combination of bioclimatic stage and lithology' gi ven a biogeographical context, and a unique successional sequence leading to a single climax community (i. e. a vegetation series (VS)). Information issued from both literature and a team of phytosociologists possessing detailed knowledge about Portuguese vegetation, namely about forests and its seria1 vegetation, was acknowledged as a starting point for the construction of such a habitat-vegetation correspondence model. First, a bioclimatic map concerning the "Worldwide Bioclimatic Classification System" (WBCS) of RIVAS-MARTINE(1Z9 81 -2004), obtained by multivariate grostatistical interpolation issuing from the work of MESQUITA(2 005), was set. Severa1 partia1 matrices, one for each biogeographical Province, combined such habitat statements to VS. Initial incoherence due to vagueness of statements led to an important amount of both superimposition of VS and habitat gaps in the matrices. Further rearrangement of the table according to known field distribution of VS by experts allowed setting an approximate univocal correspondence VS-habitat. Finally, an intersection of bioclimatic, lithology and biogeographic maps yielded over a thousand habitat combinations to be associated each to a single VS through implementation of the matrices as a set of rules. Again, inconsistencies were solved likewise, but this time by direct observation of the map by experts. Keeping of phytosociological consistency and fidelity to information on actual vegetation field distribution was always mandatory during the process
- Geographic variation among iberian communities of the exotic halophyte Cotula coronopifoliaPublication . Costa, José Carlos; Neto, C.; Arsénio, Pedro; Capelo, J.The exotic annual forb Cotula coronopifolia has locally invaded salt marsh communities naturally dominated by Spergularia marina along large parts of the Iberian coastline. While the floristic composition of C. coronopifolia dominated communities on the Atlantic coast of northern Portugal has already been described, this information was missing for the southern part of the country. We carried out a phytosociological study at 21 sites along the south-western and southern coast of mainland Portugal to determine the ecology and syntaxonomical status of these communities, and to compare them to the Atlantic ones. Plant communities co-dominated by C. coronopifolia and S. marina were generally found in the sub-halophilous inner part of salt marshes. They occupied gaps within taller perennial vegetation (Juncus maritimus formations), such as small pools temporarily inundated with brackish waters. Southern communities differed from the northern ones by the high abundance of Triglochin barrelieri and the absence of salt-intolerant species that are present in the Atlantic communities. This difference may result from the drier summer climate in southern regions, leading to intense water evaporation and thus, more saline conditions. We propose to classify the Mediterranean communities in a new association, the Cotulo coronopifoliae– Triglochinetum barrelieri. High abundance of Limonium diffusum further allowed the distinction of a new subassociation limonietosum diffusi for the southernmost part of Portugal. Results show that invasive exotic plants can form new phytosociological associations with a characteristic species composition, but that these community types, despite being dominated by the same invader, still show ecological and geographical differentiation.
- Uma ericácea nova para a flora portuguesaPublication . Capelo, J.; Bingre, P.; Arsénio, Pedro; Espírito-Santo, Maria Dalila
- The landscape and plant communities of Serra da ArrábidaPublication . Costa, José Carlos; Capelo, J.; Arsénio, Pedro; Monteiro-Henriques, T.The field trip takes place in the biogeographic territories of the Sadensean-Dividing Portuguese Subprovince (Coastal Lusitan- Andalusian Province, Mediterranean Region), throughout the upper thermomediterranean thermotype and subhumid ombrotype.
- Vegetação potencial das margens das ribeiras do AlgarvePublication . Espírito-Santo, Maria Dalila; Costa, José Carlos; Capelo, J.; Arsénio, PedroDuring the summer and fall of 1998, a field survey was conducted in the temtory adjacent to the main waterways of the Algarve region, regarding the flora and vegetation of temestrial systems associated to rivers. These studies where integrated in the Hidrographic Ba.in Plan for Algarve's Rivers, aiming to recognise and establish the main landscape units that form the mosaic of the referred temtory. This communication presents the results of the survey relative to the syccessional stages of Algarve's riparian vegetation, adjacent vegetation and also salt marshes and dunes vegetation. The recognition of the region's potentiai natural vegetation, in order to evaluate the riparian vegetation's conservation state, is obtained through the use of an easy-touse field fom.