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- The use of large databases to characterize habitat types: the case of Quercus suber woodlands in EuropePublication . Agrillo, Emiliano; Alessi, Nicola; Jiménez-Alfaro, Borja; Casella, Laura; Angelini, Pierangela; Argagnon, Olivier; Crespo, Guillermo; Fernández-González, Federico; Monteiro-Henriques, Tiago; Neto, Carlos; Attorre, FabioThe conservation of habitat types has been recognized to be of relevant importance for the conservation of biodiversity and is a major concern in the European Union. With the 92/43/EEC Habitats Directive, the European Commission targeted these habitat types, which conservation must be ensured by Member States. In this context, the Habitat type 9330 “Quercus suber forests” is intended to ensure the conservation of cork oak woodlands in Europe. To support the enhancement of nature conservation policies, in this study we provide a classifcation of cork oak woodlands in Europe using a large vegetation database. We identify four major groups with clear biogeographic diferences and characterize them by lists of indicator species. We also provide distribution maps based on occurrence data and the modelled potential area of distribution as an additional tool for conservation. This study ofers a contribution to the comparative description of the European Q. suber woodlands subtypes and to establish a protocol for habitat monitoring and assessment.
- Evolución de la cubierta vegetal después de una perturbación por deslizamientosPublication . Lopes, Luis; Neto, Carlos; Oliveira, Sérgio; Zêzere, JoséLa perturbación produce alteraciones en los ecosistemas afectando la evolución por sucesión ecológica y, consecuentemente, es considerada como uno de los principales factores que afectan al desarrollo de la vegetación. Por ello, ejerce un papel crucial en el mantenimiento de la biodiversidad, teniendo un papel ecológico muy importante a través de la creación de hábitats complejos y únicos. Así, para la determinación del nivel de diferenciación entre sectores internos de los deslizamientos en función de la vegetación, conjuntamente con una evaluación de las alteraciones entre comunidades afectadas y adyacentes, se han analizado mediante un muestreo estratiicado, tres sectores del deslizamiento (cicatriz, cuerpo y pie), culminando en la identiicación de 115 taxones. Las laderas inestables permiten el surgimiento de especies endémicas donde el valor de conservación y la riqueza lorística es máxima en la fase intermedia del proceso de recuperación iniciado con la perturbación. La ocurrencia periódica de deslizamientos y consecuente regresión sucesional se interpreta como positiva y necesaria.
- Finding the boundary between Eurosiberian and Mediterranean salt marshesPublication . Costa, J. C.; Arsénio, P.; Monteiro-Henriques, T.; Neto, Carlos; Pereira, E.; Almeida, T.; Izco, J.In continental Portugal it is generally recognized that the Ria de Aveiro is the coastal limit between Mediterranean and Eurosiberian regions. Considering salt marshes flora and vegetation communities, the Tagus River estuary seems typically Mediterranean, while the Ria de Aveiro lagoon seems typically Eurosiberian, therefore the boundary between the two regions might be found among the smaller salty areas existing between the two referred wetlands (namely the Óbidos Lagoon, the Tornada and Mondego rivers). Although tide height is a sound explanation for the floristic differences between Eurosiberian and Mediterranean saltmarshes, the fact is that the southwest Portuguese Atlantic salt marshes present Mediterranean climate and flora, despite its greater tide heights if compared to the Mediterranean Basin. Conversely, Mediterranean climate by its own is not enough to explain those florisitc differences, as it exits north of Aveiro. We introduced the importance of sea-surface temperature in order to detail the boundary between the two regions. Despite climate and hydrologic regime being Mediterranean between the Tagus and the Ria de Aveiro, the cold Atlantic waters seem to influence the flora and the vegetation of the present salt marshes. It is proposed to classify as Eurosiberian all salt marshes north of the Tagus Basin.
- Vegetation evolution by ecological succession as a potential bioindicator of landslides relative age in Southwestern Mediterranean regionPublication . Lopes, Luís Filipe; Oliveira, Sérgio; Neto, Carlos; Zêzere, JoséLandslides have a direct impact in the ecosystems dynamics being considered one of the main vegetation perturbation processes. Our objective is to determine the relation between vegetation cover evolution and time period after landslide disturbance, and therefore to assess the potential use of vegetation evolution within landslide areas as temporal bioindicators of landslide activity, in order to determine landslide relative age. Four rotational slides of known relative age, located in the Grande da Pipa River basin (Arruda dos Vinhos, Portugal) were selected. The methodology includes four main steps: (1) to identify the flora and vegetation differences between the main landslide sectors (scarp, body, foot); (2) to find out if the differences in floristic composition and vegetation structure are reflected in the succession process; (3) to find out if the succession process has produced different seral stages along the longitudinal gradients; (4) to compare the succession process in landslide affected areas with the undisturbed adjacent areas. The data points towards a slow evolution of the vegetation in the period following the disturbance, being necessary long periods for the perturbed area reach vegetation characteristics similar to the ones of the unperturbed areas. The progressive succession is rapid in the foot, slow in the body and extremely slow in the scarp. The presence of orchids in the body may be considered as an age bioindicator of more than 15 years since landslide disturbance. In the case of the older landslide (> 50 years), it corresponds to the evolved stage close to the potential natural vegetation.
- Active or passive recovery? Discussing implications of vegetation diversity in unmanaged salt marshesPublication . Almeida, Diana; Neto, Carlos; Costa, José Carlos
- The impacts of land-use changes on the recovery of saltmarshes in PortugalPublication . Almeida, Diana; Neto, Carlos; Esteves, Luciana S.; Costa, José CarlosHuman-induced land-use changes have resulted in loss and degradation of intertidal environments worldwide. Saltmarsh ecosystem dynamics in Portugal are greatly influenced by historic uses and consequent habitat degradation. This study uses an original approach combining vegetation surveys and spatial analysis of historic maps and aerial photographs to assess the effects of land use changes on saltmarshes in two areas in the Algarve, southern Portugal. Historical maps from c. 1800 and aerial photographs from 1958 to 2010 were analyzed to map saltmarsh ecosystems and quantify land-use changes in the Alvor estuary and Arade River. Between c. 1800 and 2010 more than half of saltmarshes were lost due to dyke building and saltmarsh reclamation for agriculture. In mid-1960s, the abandonment of reclaimed agricultural areas resulted in the recolonization of saltmarsh vegetation, which developed physically separated from natural marshes. In the study area, these saltmarshes naturally evolved into two distinct typologies: (1) enclosed mixed marshes, formed by patches of brackish, freshwater and some invasive species developing due to saline intrusion in areas where dykes have not been breached; and (2) tidally-restored saltmarshes, formed in areas where dyke breaching allows incursion of tides and development of a vegetation structure similar to natural saltmarshes. In Europe, passive (without human intervention) and active (artificially planned) saltmarsh restoration are important mechanisms for voluntary or statutory re-creation of intertidal habitats. Improved understanding of the factors influencing the development of distinct saltmarsh typologies through passive ecosystem recovery can provide new insights to support decision-making concerning intertidal habitat restoration.
- Phylogenenetic approach of the section Bulbocodii D.C. of Narcissus based on cpDNA: a case of taxonomic inflation?Publication . Fonseca, J. P.; Levy, A.; Henriques, R.; Costa, J. C.; Neto, Carlos; Robalo, J.In this paper, we analyzed the phylogeny of the section Bulbocodii (genus Narcissus; Amarillydaceae) using the matK and trnL-F fragments of cpDNA in order to review the validity of the recognized taxa. Our results indicate that Narcissus obesus should be considered a valid species, and that N. blancoi is a distinct taxon. In addition, seven previously recognized species, N. juressianus, N. subnivalis, N. graellsii, N. conspicuus, N. citrinus, N. nivalis, and N. quintanilhae, should be assigned to na infraspecific rank under N. bulbocodium, as they are not valid species. In addition, we analyzed the distribution of the three morphological characters widely used in the systematics of this section and found that their variation does not agree with the phylogenetic results, rendering these characters limited taxonomical utility. This result suggests that the section Bulbocodii shows high morphological lability, which can explain the proliferation of nominal species.
- The scrubland of limestone-derived decarbonated soils of the western Iberian PeninsulaPublication . Costa, J. C.; Pinto-Gomes, C.; Lopes, M. C.; Neto, Carlos; Monteiro-Henriques, T.; Arsénio, P; Silva, V.; Capelo, J.; Lousã, M.; Rivas-Martínez, S.In the present article, the proposal of a new suballiance, Lavandulo luisieri-Cistenion albidi, is presented, constituted by chamaephytic and nanophanerophytic communities in eroded decarbonated soils derived from limestones (leptosols, chromic luvisols and cambisols) in the dry to lower hyperhumid, thermo-mesomediterranean bioclimatic levels. It is distributed throughout the western Iberian Peninsula in the Coastal Lusitan-Andalusian and Lusitan-Extremadurean biogeographical territories. It is positioned in the Ulici argentei-Cistion ladaniferi, Lavanduletalia stoechadis, Cisto-Lavanduletea. The new associations Anthyllido maurae-Ulicetum jussiaei, Sedo albi-Cistetum crispi and Thymetum congesti are also described. The multivariate analysis confirmed the segregation of this new suballiance, as well as the new associations
- Predicting land use and land cover changes for landscape planning: an integration of Markov chains and Cellular automata using GISPublication . Gutierres, F.; Godinho-Ferreira, P.; Reis, Eusébio; Neto, CarlosThe spatial dynamics of landscapes are the consequence of a multiplicity of relations among physical, biological and social forces. So, it is essential the assessment of the driving forces related to Land Use and Land Cover changes (LULC) to understand the change process. The stochastic modeling technique in Geographical Information System (GIS) - Markov Chain (MC) analysis and Cellular Automata (CA) allows the predictions of future changes based on changes that have occurred in the past. This chapter aims to present a dynamic simulation model for LULC changes in ‘Sado Estuary’ and ‘Comporta-Galé’ Natura 2000 Sites (Portugal) for the beginning of the second half of the XXI century by using MC and CA. Regarding the quantification of the fragmentation processes and LULC changes in ‘Sado Estuary’ and ‘Comporta- Galé’ Natura 2000 Sites, these models are able to reveal non-obvious trends in the data and to describe ecological patterns. From an applied research point of view, this approach is useful to identifying adequate planning and management strategies for coastal ecosystems, for monitoring and planning natural and protected environments.
- As comunidades vegetais sobre solos ultrabásicos no Alto Alentejo (Portugal)Publication . Antunes, João Henriques Castro; Aguiar, Carlos; Neto, Carlos; Costa, José CarlosNas imediações de Cabeço de Vide, nos concelhos de Fronteira e de Alter do Chão ocorre um território complexo, em termos geológicos, alternando rochas calcárias, com rochas graníticas e com ultrabasitos serpentinizados. Estas últimas constituem uma mancha contínua com relativa homogeneidade que nos permitiu efectuar o estudo da sua vegetação aqui apresentado. Em termos bioclimáticos, este território insere-se no andar mesomediterrânico inferior, sub-húmido euoceânico atenuado. Esta vegetação é muito original visto quc todas as cl)mun.idades que observámos ão originais: Rhamno laderoi-Quercetum rotundifoliae geni felOSlIm /rislrieis subass. nova, Genise/um histricis-hirsutae asso nova, Armerio Iinkiani-Cenrallretwn be·lhllricae asSo nova e Plan/aga aji-aeOmpheliodelllm lil1ifoliae asso nova. A primeira é um azinhal em que a. inala a presença de RhalllJ7w lClderoi e as diferenciai' da nova subassociação Genisra histrix, Asparagus aphy/lus e Cylisl/S baelic /ls. A egwlda é um mato caracterizado por Genisla hirsllIa e Genista /riSfl'ix e pela ausência de Cisllls tae/anifel', Cisl/ls albidus e Cis{u.l' mOIl1>peliensis. A terceira é constituída por hemicriptófitos herbáceos vivazes e geófitos caracterizada pelos endemismos Centaurea bethurica e Armeria Iinkiana acompanhada de diversas plantas da Festuco-Brometea. A última é uma comunidade terofitica caracterizada por Omphalodes Iinifolia e diversas espécies da Brachyp odietalia distachyi.