Browsing by Author "Cunha, A. H."
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- Biomares, a LIFE project to restore and manage the biodiversity of Prof. Luiz Saldanha Marine ParkPublication . Cunha, A. H.; Erzini, Karim; Serrão, Ester; Gonçalves, E.; Borges, R.; Henriques, M.; Henriques, Victor; Guerra, M.; Duarte, C.; Marba, N.; Fonseca, MThe Marine Park Prof. Luiz Saldanha, in the coast of Arrabida, is the first marine park in continental Portugal. This area is a Nature 2000 site and is considered to be a hotspot for European marine biodiversity. In 2005, the management plan of the park was implemented, ending several habitat menaces, thereby allowing an application to the LIFE-NATURE Programme. The LIFE-BIOMARES project aimed at the restoration and management of the biodiversity of the marine park through several actions. The restoration of the seagrass prairies that were completely destroyed by fishing activities and recreational boating, was one of the most challenging. It included the transplanting of seagrasses from donor populations and the germination of seagrass seeds for posterior plantation to maintain genetic diversity in the transplanted area. One of the most popular actions was the implementation of environmental friendly moorings to integrate recreational use of the area with environmental protection. Several dissemination and environmental education actions concerning the marine park and the project took place and contributed to the public increase of the park acceptance. The seabed habitats were mapped along the park and a surrounding area to 100 m depth in order to create a habitat cartography of the park and to help locate alternative fishing zones. Biodiversity assessments for macrofauna revealed seasonal variations and an effect of the protection status. Preliminary results are presented and show that the marine park regulations are having a positive effect on biodiversity conservation and sustainable fisheries, thereby showing that these kind of conservation projects are important to disseminate coastal conservation best practices. The Biomares project is a model project that can be followed in the implementation of marine reserves and the establishment of the Natura 2000 marine network.
- Estimation of available seagrass meadow area in Portugal for transplanting purposesPublication . Cunha, A. H.; Assis, J.; Serrão, EsterSeagrasses are marine flowering plants found in shallow coastal habitats around the world. These plants create a habitat of substantial importance from an ecological, economic and biodiversity point of view. Unfortunately, there have been considerable losses of seagrass habitat worldwide, leading to increasing interest on the development of seagrass restoration and rehabilitation projects. These projects, often developed as a mitigation tool, deeply benefit from the spatially explicit information included in Geographic Information Systems (GIS). Thus, to have seagrass area estimates for transplanting purposes and, to be able to monitor transplanting impacts, a large-scale GIS map was build for Sado and Mira River Estuaries, Portinho da Arrábida Bay and Ria Formosa regions using: (1) aerial photography analysis, (2) photo-interpretation, (3) on-site groundtruthing surveys and (4) statistical analysis. Habitat boundaries were evaluated through aerial photography, and a complete set of selected sites were visited for groundtruth validation, using 4 types of transect methods (along the shore-line, free-diving, scuba diving and boat transects). Twelve thousand, six hundred and fifty two hectares (12652.17 ha) were assessed, 3944 groundtruth points were recorded and 3 seagrass species were identified and mapped (Zostera marina, Zostera noltii and Cymodocea nodosa). Ria Formosa had the largest distribution area of seagrass species (241.04 ha), followed by Sado Estuary (32.68 ha). Mira Estuary had only one seagrass meadow and in Portinho da Arrábida Bay no seagrass meadows were registered. Zostera noltii was the most abundant species in both regions, followed by Cymodocea nodosa and Zostera marina. The error assessment for species distribution area and diversity, estimated through kappa statistics based on error matrices, gave a perfect agreement value (K=0.912) to the methodology used.
- Findkelp, a GIS-based community participation project to assess portuguese kelp conservation statusPublication . Assis, J.; Tavares, D.; Tavares, J.; Cunha, A. H.; Alberto, F.; Serrão, EsterIn almost any Atlantic coastal area of Europe where there is a suitable substratum and adequate water quality, one or more species of kelp may be found. Their high productivity and complex biological structure make kelps especially important members of their communities, particularly when present in dense stands known as “kelp forests”. Currently, these species are subject to important novel constraints of physical and anthropogenic origins that can strongly modify their sustainability, their distribution and the biodiversity of associated species. Along the Portuguese coastline there is a perception by the local and scientific communities that some kelp species abundance is declining, particularly at the southern coast. Nevertheless, no large-scale spatial study of kelp abundance and diversity has been done. With the acronym Findkelp, this study aimed to assess from May to August 2008, the Portuguese kelp conservation status through community participation, field-based observations and large-scale Geographic Information System (GIS) technology. A communication strategy towards scuba divers and other coastal zone users was made to build and educate a team of informed volunteers that worked as independent observers, reporting georeferenced data in an electronic data-base available on the project’s website. At randomly underwater chosen locations (n=56) from the volunteers reported sites (n=388), structural descriptors of kelp populations were groundtruthed, by means of non-destructive sampling techniques (3x50m belt-transects). By crossing the volunteer’s reported data with the groundtruthed data, using error matrices and Kappa statistics with concordance agreement scales, a Portuguese coast line GIS map with perfect agreement (K=0.827) was made including the current distribution, diversity and conservation status of 6 kelp species.
- Seagrasses in Portugal: a most endangered marine habitatPublication . Cunha, A. H.; Assis, J.; Serrão, EsterNumerous reports of seagrass decline around the world indicate that seagrass habitats are undergoing a global crisis with important consequences for coastal biodiversity, environmental status and economy, reflecting their vulnerable and overlooked status within many conservation agendas. This paper describes the results of the first extensive survey of this habitat in Portugal. It shows the present cover distribution and declining trends of seagrasses on the Portuguese coast (1980–2010), identifies environmental and conservation issues, and discusses challenges for long-term survival. Seagrass populations of the Portuguese coast are also facing an unprecedented decline in distribution, matching the general trends described for most world seagrasses. The results of this investigation show a dramatic decrease of seagrass cover in Portugal in the last 20 years. This decrease followed different trends for the three species present on this coast. Zostera noltii, having disappeared from some systems by almost 75%, is still the most abundant species, present in 10 of the 18 sites assessed. Zostera marina is presently the most endangered seagrass species in Portugal, as it disappeared from six of eight historical locations and faces extinction from the Portuguese territory if measures are not taken to assure the protection of the last regions left with populations. Cymodocea nodosa has a geographic distribution range limited to the southern/southwestern coasts, and its current conservation status is uncertain, although there is evidence for the recent occurrence of several population bottlenecks. Management questions are discussed and actions to improve habitat conservation are suggested.
- Spatial synchronies in the seasonal occurrence of larvae of oysters (Crassostrea gigas) and mussels (Mytilus edulis/galloprovincialis) in European coastal watersPublication . Philippart, C. J. M.; Araújo Amaral, Ana Margarida; Asmus, R.; van Bleijswijk, J.; Bremner, J.; Buchholz, F.; Cabanellas-Reboredo, M.; Catarino, D.; Cattrijsse, A.; Charles, F.; Comtet, T.; Cunha, A. H.; Deudero, S.; Duchêne, J. - C.; Fraschetti, S.; Gentil, F.; Gittenberger, A.; Guizien, Katell; Gonçalves, Jorge Manuel Santos; Guarnieri, G.; Hendriks, Iris; Hussel, B.; Vieira, R. P.; Reijnen, B. T.; Sampaio, I.; Serrão, Ester; Pinto, I. S.; Thiebaut, E.; Viard, F.; Zuur, A. F.Reproductive cycles of marine invertebrates with complex life histories are considered to be synchronized by water temperature and feeding conditions, which vary with season and latitude. This study analyses seasonal variation in the occurrence of oyster (Crassostrea gigas) and mussel (Mytilus edulis/galloprovincialis) larvae across European coastal waters at a synoptic scale (1000s of km) using standardised methods for sampling and molecular analyses. We tested a series of hypotheses to explain the observed seasonal patterns of occurrence of bivalve larvae at 12 European stations (located between 37 N and 60 N and 27 W and 18 E). These hypotheses included a model that stated that there was no synchronisation in seasonality of larval presence at all between the locations (null hypothesis), a model that assumed that there was one common seasonality pattern for all stations within Europe, and various models that supposed that the variation in seasonality could be grouped according to specific spatial scales (i.e., latitude, large marine ecosystems and ecoregions), taxonomic groups, or several combinations of these factors. For oysters, the best models explaining the presence/absence of larvae in European coastal waters were (1) the model that assumed one common seasonal pattern, and (2) the one that, in addition to this common pattern, assumed an enhanced probability of occurrence from south to north. The third best model for oysters, with less empirical support than the first two, stated that oysters reproduced later in the south than in the north. For mussels, the best models explaining the seasonality in occurrence of larvae were (1) the model that assumed four underlying trends related to large marine ecosystems, and (2) the one that assumed one common seasonal pattern for larvae occurrence throughout Europe. Such synchronies in larval occurrences suggest that environmental conditions relevant to bivalve larval survival are more or less similar at large spatial scales from 100s to 1000s of km. To unravel the underlying mechanisms for this synchronisation is of particular interest in the light of changing environmental conditions as the result of global climate change and the possible consequences for marine food webs and ecosystem services.
- The rediscovery of Caulerpa prolifera in Ria Formosa, Portugal, 60 years after the previous recordPublication . Cunha, A. H.; E, Varela-Álvarez; Paulo, D. S.; Sousa, Inês; Serrão, EsterThe westernmost occurrence of Caulerpa prolifera on the Atlantic European coast has been accepted in recent decades, to be Huelva province, southern Spain. In April 2011, this species was found in Ria Formosa, southern Portugal, extending its westernmost limit along the Iberian Peninsula coastline. In the course of research into this species it was discovered that this alga had been found in Ria Formosa in the 19th century by the naturalist Welwitsch and subsequently in the 1930s by others but it was never found in the many field studies conducted in Ria Formosa during the past few decades. The species had therefore either become extinct in the area or persisted as a cryptic undetected stage. In order to investigate the source of colonization and to verify the genetic identity, a partial cpDNA region (tufA gene) was sequenced. Comparisons of nucleotide similarity in sequences from the Ria Formosa and from populations of the Atlantic and Mediterranean confirmed the Caulerpa prolifera identification and gave clues about a possible origin of this population as deriving from expansion of a Mediterranean source rather than one from the western Atlantic.