Browsing by Author "Silva, Eduardo Ferreira da"
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- Integrating geochemical (surface waters, stream sediments) and biological (diatoms) approaches to assess AMD environmental impact in a pyritic mining area: Aljustrel (Alentejo, Portugal)Publication . Luís, Ana Teresa; Durães, Nuno; Almeida, Salomé Fernandes Pinheiro de; Silva, Eduardo Ferreira daAljustrel mines were classified as having high environmental hazard due to their large tailings volume and high metal concentrations in waters and sediments. To assess acid mine drainage impacted systems whose environmental conditions change quickly, the use of biological indicators with short generation time such as diatoms is advantageous. This study combined geochemical and diatom data, whose results were highlighted in 3 groups: Group 1, with low pH (1.9-5.1) and high metal/metalloid (Al, As, Cd, Co, Cu, Fe, Mn, Ni, Pb, Zn; 0.65-1032 mg/L) and SO4 (405-39124 mg/L) concentrations. An acidophilic species, Pinnularia aljustrelica, was perfectly adapted to the adverse conditions; in contrast, teratological forms of Eunotia exigua were found, showing that metal toxicity affected this species. The low availability of metals/metalloids in sediments of this group indicates that metals/metalloids of the exchangeable fractions had been solubilized, which in fact enables metal/metalloid diatom uptake and consequently the occurrence of teratologies; Group 2, with sites of near neutral pH (5.0-6.8) and intermediate metal/metalloid (0.002-6 mg/L) and SO4 (302-2179 mg/L) concentrations; this enabled the existence of typical species of uncontaminated streams (Brachysira neglectissima, Achnanthidium minutissimum); Group 3, with samples from unimpacted sites, showing low metal/metalloid (0-0.8 mg/L) and SO4 (10-315 mg/L) concentrations, high pH (7.0-8.4) and Cl contents (10-2119 mg/L) and the presence of brackish to marine species (Entomoneis paludosa). For similar conditions of acidity, differences in diversity, abundance and teratologies of diatoms can be explained by the levels of metals/metalloids. (C) 2015 The Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V.
- Successful use of geochemical tools to trace the geographic origin of Long-Snouted Seahorse Hippocampus guttulatus raised in captivityPublication . Cabral, Ana Elisa; Ricardo, Fernando; Patinha, Carla; Silva, Eduardo Ferreira da; Correia, Miguel; Palma, Jorge; Planas, Miquel; Calado, RicardoThe global market of dried seahorses mainly supplies Traditional Chinese Medicine and still relies on blurry trade chains that often cover less sustainable practices targeting these pricey and endangered fish. As such, reliable tools that allow the enforcement of traceability, namely to confirm the geographic origin of traded seahorses, are urgently needed. The present study evaluated the use of elemental fingerprints (EF) in the bony structures of long-snouted seahorses Hippocampus guttulatus raised in captivity in two different locations (southern Portugal and Northern Spain) to discriminate their geographic origin. The EF of different body parts of H. guttulatus were also evaluated as potential proxies for the EF of the whole body, in order to allow the analysis of damaged specimens and avoid the use of whole specimens for analysis. The contrasting EF of H. guttulatus raised in the two locations allowed their reliable discrimination. Although no single body part exactly mimicked the EF of the whole body, seahorse trunks, as well as damaged specimens, could still be correctly allocated to their geographic origin. This promising forensic approach to discriminate the geographic origin of seahorses raised in captivity should now be validated for wild conspecifics originating from different locations, as well as for other species within genus Hippocampus.
- Use of isotopic and elemental fingerprints for seahorse species discrimination and traceability of geographic originPublication . Cabral, Ana Elisa; Calado, Ricardo; Palma, Jorge; Ricardo, Fernando; Silva, Eduardo Ferreira da; Patinha, Carla; Planas, MiquelSeahorses (Hippocampus spp.; Family Syngnathidae) are mainly targeted by Traditional Chinese Medicine, curio and ornamental trade, as dried or live specimens. Traceability tools may help fill the gaps on supply chains, securing information on geographic origin and identification of traded specimens. Fin-clipping, a non-lethal and well-established method in seahorse research, offers a potential approach to trace the geographic origin and certify the aquaculture of these flagship species. As such, this study aimed to investigate the existence of differences in isotopic profiles of four seahorse species cultured at research centers located in southern Portugal and northern Spain, as well as between cultured Hippocampus guttulatus sourced from two research centers, and between wild and cultured specimens of this species. This research also evaluated the potential of combining isotopic and elemental fingerprints for seahorse species discrimination, through inductively continuous-flow isotope ratio mass spectrometry (IR-MS) and plasma mass spectrometry (ICP-MS). Species cultured at the same research centers exhibited similar stable isotope composition (delta 13C and delta 15N), except in the case of temperate H. guttulatus from northern Spain, which differed significantly from tropical species H. kuda and H. reidi. These differences could be due to phylogenetic dissimilarities and differences in seawater temperature. The delta 15N composition allowed to discriminate between cultured H. guttulatus from the two research centers and between cultured and wild specimens. While dorsal fin isotopes alone did not prove to be a reliable tool for the discrimination of different cultured species, combining them with elemental profiles from seahorses' whole-body allowed to successfully discriminate between H. kuda and H. reidi. This preliminary research demonstrates the potential of stable isotope and elemental analyses for tracing seahorses' geographic origin and species identification. However, further research should be performed to validate these findings for wild specimens, particularly those from illegal, unreported and unregulated (IUU) fisheries and trade.