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- 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.
- 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
- Vegetation classification and conservation aspects of Atlantic dune pine forests in the southwest of the Iberian PeninsulaPublication . Costa, José Carlos; Neto, Carlos; Monteiro-Henriques, Tiago; Pina, Ana Rita; Aguiar, Carlos; Mascia, Francesco; Bonari, GianmariaThis study refines the classification framework for Portuguese dune pine forests included in the alliance Coremato albi-Pinion pinastri at the association level after the syntaxonomic revision of Mediterranean pine forests of the class Pinetea halepensis. We collected 61 original vegetation plots between 2017 and 2022 in the southwestern Iberian Peninsula, analysing them through Principal Co- ordinate Analysis (PCoA) and UPGMA clustering. Numerical analysis identified four associations within the alliance Coremato albi-Pinion pinastri, specific to the sandy Atlantic coast of the Iberian Peninsula. Of these, three associations are newly described (Cytiso grandiflori-Pinetum pinastri, Aristolochio baeticae-Pinetum pineae, and Ulici australis-Pinetum pineae). Our study classified pine forests on sand in southwestern Iberia and identifies conservation-significant species in their understory. The floristic diversity in these psammophilous pine forests is enhanced by numerous endemics and relic species from the Tertiary period, shaped by past climatic refugia and multiple floristic migration routes, including Atlantic, Mediterranean, and North African pathways. This has resulted in a unique blend of thermophilic, oceanic, and xeric species with high conservation value. Our study contributes to the understanding of Atlantic dune pine forest ecology and inform habitat conservation efforts.
- Teixedos no noroeste da Península IbéricaPublication . Portela-Pereira, Estevão; Monteiro-Henriques, Tiago; Casas, Carme; Forner, Nuno; Garcia-Cabral, Isabel; Fonseca, João Paulo; Neto, CarlosA descrição do Habitat 9580* da Rede Natura 2000, nomeadamente no Noroeste ibérico, carece de informação fitossociológica que facilite a sua interpretação. Até agora esta é feita essencialmente enumerando os vários sintáxones em que Taxus baccata tem presença confirmada. Tanto pela falta de inventários nestas comunidades vegetais, mas também por se considerarem os teixedos como simples faciações das florestas envolventes, esta interpretação torna-se inconsequente, já que na maior parte dos casos não se refere a teixedos, i.e., bosquetes (co)dominados por Taxus baccata (Habitat 9580*), mas a indivíduos mais ou menos isolados no seio de outras comunidades. Com base numa análise DiffVal de 33 inventários de teixedos do NW ibérico, foi possível diferenciar e classificar três novos sintáxones florestais (co)dominados por Taxus baccata. Nos territórios lusitanos distinguem-se os teixedos geresianos, propostos como Eryngio juresiani-Taxetum baccatae subass. typicum, dos muito raros estrelenses Eryngio juresiani-Taxetum baccatae subass. loniceretosum hispanicae, enquanto que para os teixedos W cantábricos, claramente diferenciáveis dos lusitanos, propõe-se o nome Corylo avellanae-Taxetum baccatae.
- The Tróia Peninsula: an Aeolian Sedimentological LegacyPublication . Neto, Carlos; Geraldes, Miguel; Almeida, DianaThe integration of studies from fields, such as geomorphology, palynology, history, archaeology and phytogeography, enables assessing the genesis and evolution of the most prominent Portuguese sand spit—the Tróia Peninsula. Data suggests that the spit has formed from Grimaldian dunes converted into barrier islands during the Holocene transgression, and coalesced by the accumulation of sediments transported by the northbound longshore drift. The Tróia Peninsula is integrated in one of the most important Portuguese natural protected areas. It holds a set of flora and vegetation of paramount relevance towards protection and conservation in accordance with the Natura 2000 Network. Its position acts as a barrier against the Atlantic Ocean, having allowed the development of the Sado estuary lagoon, which contains mud flats and salt marsh ecosystems, habitats for a wide range of flora and fauna, some of which with special protection status. The Tróia Peninsula forms indeed a natural protective barrier for the Natural Reserve of the Sado Estuary. The genesis of the peninsula, discussed in the present work, combined with the fact that it is made up exclusively of sand, make it very vulnerable to environmental changes, including sea level rise.
- Characteristics of novel urban vegetation in two Portuguese urban regionsPublication . Pereira, Estevão; Neto, Carlos; Brito-Henriques, Eduardo; Soares, Ana Luísa; Azambuja, Sónia TalhéUrban novel ecosystems were sampled across vacant sites in two Portuguese urban regions. The flora were studied with a focus on species’ origin, life form, ecological, chorological and naturalisation types. A multivariate constrained ordination technique was used to identify relationships between plant composition and environmental factors. The vegetation of the two urban regions shows differences, highlighting biome influence, as well as due to climatic variables and (to a lesser degree) soil characteristics and lithology. Although native species are clearly dominant, the frequency of non-native species is high and most are potentially or effectively invasive. In the ecological spectrum, the dominance of opportunistic ruderal species suggests a risk of biotic homogenisation in these ecosystems, which is also noticeable in the analysis of life form, but less in chorological and nativeness spectra. Portuguese novel urban ecosystems are, therefore, simultaneously an opportunity, since spontaneous vegetation management is more cost effective and can bring wilderness to cities; and a hazard, because invasive species must be controlled to support biodiversity conservation efforts.
- Plant communities of Namibe Saltmarshes (Southwest of Angola)Publication . Cardoso, João Francisco; Costa, José Carlos; Neto, Carlos; Duarte, Maria Cristina; Monteiro-Henriques, TiagoThis work constitutes the first phytosociological analysis of saltmarshes on the Angolan coast. Sixty-five relevés were carried out resulting in the description of six new plant associations. These saltmarshes are characterized by a lower floristic richness when compared to the Holarctic saltmarshes. Eighteen taxa were identified, some of them succulent. Saltmarshes occur from the mouth of the Cunene River to the Cuanza River, although in this last part they are already very impoverished. In the Cuanza river, saltmarshes occupy only a narrow strip in the inner sector of the mangroves in contact with continental ecosystems and are often made up of just one taxon, Sarcocornia natalensis subsp. affinis. Mangroves reach their southern limit in the city of Lobito, although they are almost extinct there. The occurrence and distribution of saltmarshes are affected by the Cold Benguela Current, that influences the west coast of Africa between Cabo da Boa Esperança and Benguela. The height of the saltmarsh’s platforms colonized by halophyte, sub-halophyte or halotolerant plants determines the flooding period and thus the plant community’s floristic composition. Soil granulometry also plays an important role in the spatial organization of plant communities. One of the main originalities of Angolan saltmarshes is the predominance of fine sandy or sandy-loam soil texture as a consequence of the proximity of the Namibe desert. The PCA segregated the different plant communities described.
- Shifts in grasses diversity patterns between two contrasting 40‐year climate periods in tropical dry islandsPublication . Duarte, Maria Cristina; Rocha, Vanézia; Fernández‐Palacios, José María; Gomes, Isildo; Neto, Carlos; Costa, José C.; Branquinho, Cristina; Romeiras, Maria M.Grasses are one of the most successful and dispersed plant families worldwide and their environmental and economic values are widely acknowledged. They dominate the landscape of Cabo Verde, the southernmost and driest archipelago of Macaronesia, and are relevant natural resources for local populations, but a comprehensive evaluation of their distribution patterns is still lacking. In this study, we aim to evaluate the potential effects of climate change using the long-term data concerning grass distribution in Cabo Verde and the widely recognized climatic variability of this archipelago, which entails a huge irregularity in spatial and temporal rainfall. We identified two contrasting climatic periods (wet, from 1929 to 1968, and dry, from 1969 to 2007) and gathered all the information available from the bibliography, herbaria, and fieldwork concerning spontaneous grass species recorded in Cabo Verde during those two periods, which amounted to 107 taxa. This information was then used to disclose the patterns of grass diversity as related to climatic and topographic variables (altitude and windward vs. leeward aspects). Different altitudinal shifts in the distribution patterns of grass species assemblages and an assemblage specific to the wet period were revealed by comparing the two climatic periods. The role of exposure in delimiting the altitudinal distribution of the various assemblages was highlighted; the trade winds clearly determine the distribution of grass assemblages. We detected shifts in the distribution of grass assemblages according to the climatic periods (related to the macroclimate) and local topographic factors (associated with mesoclimates). Also, functional traits (i.e., annuals vs. perennials, C3 vs. C4 grasses, and tropical vs. temperate species) were found to vary between wet and dry periods, as well as with altitude and with slope aspect. Understanding species distributions and the role of the climatic variability of Cabo Verde is crucial to predicting how climate change will affect them and thus to support effective management and conservation actions.