Ricardo A Melo

University of Lisbon | UL · Faculty of Science

A methodology to classify rocky shores along the North East Atlantic (NEA) region was developed. Previously, biotypes and the variability of environmental conditions within these were recognized based on abiotic data. A biological validation was required in order to support the ecological meaning of the physical typologies obtained. A database of i...

Bacteriological and technical agars are in short supply with potential consequences for research, public health and clinical labs around the world. To diagnose bottlenecks and sustainability problems that may be putting the industry at risk, we analyzed the available time-series of Gelidium global landings, the industry raw material. Data on Gelidi...

Vanadium haloperoxidases were extracted, purified and characterized from three different species of Laminariaceae--Laminaria saccharina (Linné) Lamouroux, Laminaria hyperborea (Gunner) Foslie and Laminaria ochroleuca de la Pylaie. Two different forms of the vanadium haloperoxidases were purified from L. saccharina and L. hyperborea and one form fro...

Seafood traceability is a matter of concern for producers and consumers, providing insights that can simultaneously inform the consumers on the origin of the product, nutritional value and safety while adding market value to the products. Edible seaweed harvest has been pointed out as an environmentally friendly sustainable food production solution...

Fucus vesiculosus L. is a common coastal brown seaweed associated with various benefits to hu-man health, due to its phenolic content and nutrients, used as food through different methods of consumption. This study aims to evaluate the influence of this seaweeds’ gender and growth stage on different types of biological activities as well as its che...

In the last decade, the depletion of natural resources, associated with the loss of ecosystem services (ES), has been considered a consequence of management policies which use the economic performance of the benefits derived from the natural environment as an indicator, while the natural capital is neglected. A natural capital approach (NCA) can id...

This report summarizes current threats to the Tagus estuary and adjacent ecosystems, presented in Lisbon in June 2021, and prioritizes actions to maintain or improve ecosystem services for a densely populated area close to the deep ocean.

Marine coastal and transitional ecosystems are facing increasing impacts, and often reflect the most immediate effects of environmental change, habitat destruction, and biodiversity loss. With over half of the population currently living in coastal areas, these areas are of interest for multiple uses and resources, as well as subjected to multiple...

There is an increasing demand for sea cucumbers, for human consumption, mainly from Asian markets and, as a consequence, NE-Atlantic species are now new targets for exploitation and exportation. Holothuria mammata is one of the most valuable species in Europe. However, the lack of historical economic interest in this species in most European countr...

Undaria pinnatifida is a brown alga, largely used as food in oriental countries. The purpose of this work was to analyze several bioactivities that might be present in different food preparations, relating them with the compounds present in the extracts. Aqueous extracts cooked, like a soup, as well as used in a salad, by simulating U. pinnatifida...

As tarefas do projeto têm vindo a ser todas executadas, no entanto com atrasos em algumas, por motivos diferentes. A tarefa da governança participativa (Tarefa 8) teve início com grande atraso, pelas dificuldades na contratação. Os resultados desta tarefa são essenciais para a capacitação do setor da apanha de bivalves e para dar suporte à elaboraç...

Marine forests ecosystems are typical of temperate rocky benthic areas. These systems are formed by canopy-forming macroalgae (Laminariales, Tilopteridales and Fucales) of high ecological value that provide numerous ecosystem services. These key species are also indicators of good environmental status. In recent decades, marine forests have been th...

The high demand of sea cucumbers in international markets, mostly based in Asia, has left a deep impact on the natural stock of many species, leading to an investment in aquaculture techniques in order to mitigate these impacts. This study aimed to determine the effects of stock density in rearing broodstock of Holothuria (Panningoturia) forskali D...

Fucus vesiculosus is a brown macroalgae used in food and generally considered safe to be consumed, according to EU Directive (EC 258/97). The aim of this study is to analyze the effect of food preparation on F.vesiculosus of different origins on what concerns its chemical constituents and final bioactivities. The aqueous extract of the seaweeds wer...

Neste volume é apresentada a primeira tradução para língua portuguesa do artigo original de Lynn Margulis (à altura, Lynn Sagan), publicado em Março de 1967, e que representou o início de uma longa e notória carreira em que a autora, parafraseando John M. Archibald, acima, se distinguiu de todos os que a antecederam, ou mesmo se lhe seguiram, pela...

The high demand for sea cucumbers in eastern markets, either as a protein source for human consumption or for medicinal purposes, placed an excessive pressure on natural stocks. Sea cucumber aquaculture, set as a valuable alternative for producers and highly developed in Southeast Asia, still falls short on supply. As a consequence, exploitation of...

ACOI 58 and ACOI 1257, two different Portuguese strains of colonial green microalga Botryococcus bruanii Kutz obtained from Coimbra Collection of Algae (ACOI), were evaluated on their potential for biofuel production, which was assessed from batch culture in photobioreactors under indoors and outdoors conditions using pretreated waste water and sem...

At present laboratory reagent companies are suspending supply of specialised agar products due to low availability of raw material. These bacteriological/technical agars used in laboratories around the world are predominantly obtained from species of a single red algal genus, Gelidium. Harvesting of natural populations is the only source of feedsto...

Important coastal management instruments, such as Estuary and Watershed Planning and Management Plans, require the cartographic demarcation of the boundary between the estuarine bed and fringe. This boundary has important implications on the jurisdictional areas of public entities that manage and regulate public water bodies, as well as on some asp...

O presente documento constitui o relatório final do projeto MorFeed, financiado pela Fundação para a Ciência e a Tecnologia. Listam-se abaixo os principais elementos identificadores do projeto: Referência do Projeto: PTDC/AAC-AMB/100092/2008 Área Científica: Ambiente e Alterações Climáticas Investigadora Responsável: Paula Maria de Santos Freire In...

Despite anthropogenic pressures (mainly the illegal harvesting of bivalves), and contrary to the global recession of seagrass stands, updated mapping of the intertidal zone of the Tagus estuary showed that Z. noltii has been increasing in area. It is intended that the results obtained may contribute to the definition of simple and effective strateg...

Elysia timida (Risso, 1818) colonizing the shallow waters of the Mar Menor Lagoon (Spain) exhibit a brown and a green morph. It was hypothesised that these morphs were the result of feeding preferentially on brown and green algae, respectively. E. timida and its potential food sources, Acetabularia acetabulum (Chlorophyta) and Halopteris filicina (...

Devido à crescente ocupação antrópica, as zonas marginais dos estuários encontram-se mais vulneráveis às variações e alterações do regime hidrosedimentar estuarino. A análise do comportamento morfodinâmico e a avaliação do risco à erosão e inundação daquelas zonas pressupõe o conhecimento prévio do tipo de ocupação natural e antrópico. Neste trabal...

A produção de cartografia da área intertidal de zonas costeiras ou estuarinas é geralmente pouco pormenorizada nas cartas náuticas e militares. Este facto é compreensível face aos objectivos destes instrumentos e aos elevados custos de produção de cartografia detalhada. No entanto, a importância ecológica e económica do intertidal, sobretudo em zon...

A produção de cartografia da área intertidal de zonas costeiras ou estuarinas é geralmente pouco pormenorizada nas cartas náuticas e militares. Este facto é compreensível face aos objectivos destes instrumentos e aos elevados custos de produção de cartografia detalhada. No entanto, a importância ecológica e económica do intertidal, sobretudo em zon...

Neste trabalho apresentam-se e discutem-se os critérios que serviram de base ao traçado da linha da máxima preia-mar de águas vivas equinociais (LMPMAVE) no estuário do Tejo. O traçado desta linha é essencial quando se pretende proceder à tipificação da faixa marginal em ambientes de transição, uma vez que define, na legislação em vigor, o limite e...

Seasonal and inter-annual patterns of macroalgal abundance in a Tagus Estuary oyster reef are described. Macroalgal abundance was estimated as canopy percent cover by three permanent point intercept transects over a 7-year period. Four categories were defined, corresponding to bare substrate and three different macroalgal functional-form groups: (1...

The state of the Gelidium agarophyte resource was last reviewed in 1990 and in 1998, during the First and the Second International Workshop on Gelidium, respectively. The main objective of this study is to update the information and discuss the global trends of the exploitation of this natural resource. A particular emphasis on the G sesquipedale r...

Oral presentation by RS / ABSTRACT: The state of the Gelidium agarophyte resource was last reviewed in 1990 and in 1998, during the First and the Second International Workshop on Gelidium, respectively. The main objective of this study is to update the information and discuss the global trends of the exploitation of this natural resource. A particu...

Seminar presented at University of Évora, Portugal - 2007

Two enzymes characterised as iodoperoxidases (PcI and PcII), with vanadium-dependent activity, have been purified from the brown alga Pelvetia canaliculata (L.) Decne et Thur. (Fucaceae, Phaeophyceae), collected in the Northern Portuguese coast, at Viana do Castelo. The relative molecular masses were 166 kDa for PcI and 416 kDa for PcII, as determi...

Two enzymes characterised as iodoperoxidases (PcI and PcII), with vanadium-dependent activity, have been purified from the brown alga Pelvetia canaliculata (L.) Decne et Thur. (Fucaceae, Phaeophyceae), collected in the Northern Portuguese coast, at Viana do Castelo. The relative molecular masses were 166 kDa for PcI and 416 kDa for PcII, as determi...

The state of the Gelidium agarophyte resource was last reviewed in 1990 during the First International Workshop on Gelidium. The main objective of the present study was to gather and analyse the new information made available since then, with emphasis on the G. sesquipedale resource from the Iberian Peninsula and Morocco. Other Gelidium-based resou...

Photosynthesis-light response curves of Gelidium sesquipedale from the west coast of Portugal (Cape Espichel) were determined at four different depths, 3, 10, 15 and 22 m. Data acquisition using chlorophyll a fluorescence methodology and oxygen electrode measurements were compared. Response curves were determined over an increasing range of irradia...

Vanadium-dependent iodoperoxidases from the brown seaweed Saccorhiza polyschides (Lightfoot) Batters, collected at three different locations along the Portuguese west coast, were extracted, purified and characterized. Several extraction procedures were tested, including two-phase aqueous systems. The purification of the iodoperoxidases was achieved...

Marine organisms, specially seaweeds, release to sea water large quantities of halometabolites, which are thought to result from the metabolism of the haloperoxidase enzyme. The presence of vanadium in the prosthetic group of some of these enzymes, for instance, in the brown algae A. nodosum, was ascertain by Vilter [ 1 ], and since then, vanadium...

Marine organisms, specially seaweed, release to the sea water large quantities or halometabolites witch are probably related to defense mechanisms (1). In some cases volatile halogenated compounds (for instance bromoform) can be released to the atmosphere{2). These compounds are thought to result from the metabolism of a enzyme named haloperoxidase...

The reproductive potential of the tetrasporangial phase of Gelidium robustum was studied for 16 months at two sites off Santa Barbara, California. In all samples tetrasporangial thalli were always more abundant than gametangial ones. Tetratrasporangial sori were present throughout the duration of the study but relative fecundity was highest [300–40...

Specimens of Gelidiella acerosa (Forsskâl) Feldmann et Hamel, the type species of Gelidiella Feldmann et Hamel (Gelidiellaceae, Rhodophyta), from a wide geographical range were surveyed for the absence or presence of hyphae (also called rhizines) in the thallus and for the distribution and arrangement of tetrasporangia. No cellular structures resem...

Gelidium fronds were grown in the sea under a variety of experimental conditions: on rigid, damped and tensioned test farms of various designs, in calmer and more turbulent habitats, at various depths, with and without commercial fertilizer supply. Initially, the effectiveness of a given cultivation strategy was based on the survival and growth of...

A survey and sampling of the sublittoral populations of the agarophyte Gelidium sesquipedale was carried out on July 1983 in the three zones of greater abundance of this alga in the southern portuguese coast [Algarve]. A total of 106 quadrat samples (0.16 m^2) and 37 transects perpendicular to the shore were made. covering 11.1 Km of coastline. Thr...

Some material of Carpomitra costata (Stackh.) Batt. was collected in two localities of the Portuguese coast. Berlenga Island [39° 25' N, 9° 30' W approx.] and Cape Espichel. [38° 27' N, 9° 12' W approx.] at a depth of 15-20 m, this being the first reference to this species on our continental coast. A description of the morphology of the vegetative...

Proceedings of the II Iberian Symposium on Studies of Marine Benthos, J. Ros & F.X. Niell (Eds.), Barcelona, Spain, 19-22 March, 1981.

Proceedings of the II Iberian Symposium on Studies of Marine Benthos, J. Ros & F.X. Niell (Eds.), Barcelona, Spain, 19-22 March, 1981.