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1.
Environ Monit Assess ; 192(2): 81, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31897611

RESUMO

Ecological quality (EcoQ) status of the Southwest and West coasts of South Korea was evaluated within the "National Investigation of Marine Ecosystems in Korea" in the 2015. In particular, the study dealt to assess the ecological quality of the sediments using free-living nematode communities. A total of 149 species were found in the study area, and Daptonema, Sabatieria, Parodontophora, Sphaerolaimus, and Viscosia were found as dominant genera. Statistical analysis of both environmental and faunal parameters showed an increasing human pressure from Western to Southern coasts. The community structure changed with the environmental features of the study area and allowed the detection of a suite of possible nematode indicators that might be used in monitoring studies. In particular, Dorylaimopsis spp. appeared heavy metal and organic matter resistant taxa, Sabatieria an eutrophication resistant genus, while Paracanthonchus and Neotonchus as heavy metal and organic matter sensitive genera. The principal component analysis (PCA) results showed a clear negative correlation between maturity index and both heavy metal and organic matter increasing, while diversity indices did not appear to be significantly influenced by them. Appling the thresholds of the synthetic nematode indices, the EcoQ of the study area was assessed as poor to moderate.


Assuntos
Ecossistema , Monitoramento Ambiental/métodos , Nematoides/fisiologia , Poluição da Água/análise , Animais , Ecologia , Eutrofização , Sedimentos Geológicos/química , Atividades Humanas , Metais Pesados , República da Coreia
2.
PeerJ ; 7: e6789, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31024778

RESUMO

The aim of this work was to test and analyse the bioeffects of Prunus spinosa L. (Rosacaee) fruit ethanol extract on Trichoplax adhaerens Schulze, 1883 (Placozoa) laboratory cultures which-for the first time-were employed as in vivo biological model to assess the bioactivity of a natural extract. The ethanol extract of P. spinosa was administrated during a 46 day experimental period; ultrastructural (by optical, confocal, TEM and SEM microscopy) and morphometric analyses indicated that treated Trichoplax adhaerens showed significant differences in viability, reproductive modalities, body shape and colour with respect to the control group. Finally, P. spinosa bioactive compounds seem to exert profound protective effects on T. adhaerens reproduction and phenotype. Our results may support additional investigations related to other bioactive compounds properties useful for nutraceutical preparations to be used as food supplements.

3.
Mar Pollut Bull ; 147: 171-184, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29960722

RESUMO

Ports receive a variety of contaminants related to a wide range of anthropogenic activities - including ship ballast water (BW) - that ultimately find their way to sediments. Benthic meiofauna from four Adriatic ports (Ancona, Trieste, Koper, and Split) was assessed for the main environmental pollutants, to evaluate the effects of human activities on meiobenthos and identify the most appropriate descriptor to assess the ecological quality of marine ecosystems. Sediment analysis demonstrated that Trieste and Split were the most contaminated ports, followed by Koper and Ancona. All meiofaunal parameters showed high spatial and temporal variability, in line with the marked heterogeneity of the four ports. Sand, total organic carbon, and pollutants seemed to be the variables that best explained meiofaunal patterns. Community structure and rare taxa were the meiofaunal descriptors that reflected the environmental status and biological response most accurately. The present data suggest that meiofauna can be used to assess the biological impact of BW.


Assuntos
Sedimentos Geológicos/análise , Invertebrados , Navios , Purificação da Água/métodos , Animais , Organismos Aquáticos , Biodiversidade , Monitoramento Biológico , Carbono/análise , Ecossistema , Sedimentos Geológicos/química , Itália , Mar Mediterrâneo , Compostos Orgânicos de Estanho/análise , Medição de Risco , Análise Espaço-Temporal , Inquéritos e Questionários , Instalações de Transporte , Poluentes Químicos da Água/análise
4.
Environ Toxicol Chem ; 37(9): 2439-2447, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29920754

RESUMO

Lead (Pb) is regarded as a highly toxic element that poses a serious threat to biota. A mesocosm experiment was performed to assess the influence of Pb on meiofaunal (metazoans within 45-500 µm) and benthic foraminiferal (protozoan) communities. To this end, sediments bearing such communities were incubated in mesocosms, exposed to different levels of Pb in seawater, and monitored for up to 8 wk. Concentrations of Pb <1 ppm in water did not promote a significant increase of this metal in sediments. Relatively high concentrations of Pb seemed to affect meiofaunal and benthic foraminiferal communities by reducing their richness or diversity, and the abundance of the most sensitive taxa. The mesocosm approach can be considered an effective method to document the responses of meiofaunal and benthic foraminiferal communities to various kinds and concentrations of pollutants over time. This approach allows the evaluation of dose-response relationships, validates the outcomes of field studies, and possibly confirms the sediment quality guidelines and thresholds. Environ Toxicol Chem 2018;37:2439-2447. © 2018 SETAC.


Assuntos
Monitoramento Ambiental/métodos , Foraminíferos/efeitos dos fármacos , Sedimentos Geológicos/química , Chumbo/toxicidade , Água do Mar/química , Poluentes Químicos da Água/toxicidade , Biodiversidade , Relação Dose-Resposta a Droga , Chumbo/análise , Mar Mediterrâneo , Modelos Teóricos , Poluentes Químicos da Água/análise
5.
Mar Environ Res ; 139: 19-26, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29753494

RESUMO

Marine biologists have progressively increased their consciousness of the importance of meiofauna for the benthic domain in both temperate and tropical regions. After the 1998 bleaching, Maldivian reefs (Indian Ocean) have been regarded as a vulnerable ecosystem that must be carefully monitored. Accordingly, an extensive investigation of meiofaunal distribution in the reef slopes of the Maldivian archipelago has been carried out, taking into account geographical position, type of habitat (inner vs. outer slope), inclination and depth gradient. Twenty-four taxa revealed the highest meiofaunal richness ever found in Maldivian reefs. Interestingly, Thermosbenacea and Syncarida were identified, which are two taxa that have only recently been documented in the marine ecosystem. Chaetognatha were also present, which is a group that was only considered to be planktonic until 2000, when they were also discovered in the benthos. The type of habitat, affected by different hydrodynamic conditions, was the main factor influencing the meiofaunal community's structure and diversity. In detail, the outer reefs were characterized by the highest level of diversity, confirming previous observations on the rate of coral reef growth and vitality and underlining the greater vulnerability of the inner slopes. In contrast, depth only significantly affected the community structure, but not its density or diversity. Accordingly, community structure seems to be more sensitive than abundance and diversity indices when it comes to detecting depth gradients. The 10° inclination of the inner slopes revealed the most different community structure and the greatest dominance of nematodes, leading to the lowest diversity levels.


Assuntos
Organismos Aquáticos/classificação , Biodiversidade , Recifes de Corais , Monitoramento Ambiental , Invertebrados/classificação , Animais , Antozoários , Organismos Aquáticos/crescimento & desenvolvimento , Ecossistema , Oceano Índico , Invertebrados/crescimento & desenvolvimento , Nematoides
6.
Zootaxa ; 4258(4): 375-387, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-28609913

RESUMO

Five species of suctorian ciliates belonging to four different genera attached to meiofaunal organisms of Maldivian archipelago (Suvadiva Atoll) were documented. Three rare species (Acineta sp., Thecacineta urceolata Liao & Dovgal, 2015 and Limnoricus ceter Jankowski, 1981) and one common suctorian ciliate Thecacineta calix (Schröder, 1907) are re-described from nematodes (Croconema cinctum Cobb, 1920, Desmodorella tenuispiculum Allgén, 1928 and Desmodora sp.) and harpacticoid copepod basibionts. In addition, Trophogemma colantonii n. sp. colonizing the abdomen and legs of the harpacticoid copepod Stenhelia sp. is described. The new species differs from the relative species for the less flattened cell body, the absence of both lateral bundles of tentacles and separate lateral tentacles as well as for the presence of longitudinal ribs along the cuticle. The data obtained in this survey give not only new important information on the taxonomy and distribution of Suctorea, but also new insights on their relationship with meiofaunal organisms in one of the most diverse and productive marine micro-habitat of carbonate sediments.


Assuntos
Cilióforos , Adenofórios , Animais , Copépodes , Ecossistema , Nematoides
7.
J Nematol ; 47(3): 198-206, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26527841

RESUMO

From the late 19th century, Africa has faced heavy exploitation of its natural resources with increasing land/water pollution, and several described species have already become extinct or close to extinction. This could also be the case for marine nematodes, which are the most abundant and diverse benthic group in marine sediments, and play major roles in ecosystem functioning. Compared to Europe and North America, only a handful of investigations on marine nematodes have been conducted to date in Africa. This is due to the scarcity of experienced taxonomists, absence of identification guides, as well as local appropriate infrastructures. A pivotal project has started recently between nematologists from Africa (Tunisia), India, and Europe (Italy) to promote taxonomic study and biodiversity estimation of marine nematodes in the African continent. To do this, as a first step, collection of permanent slides of marine nematodes (235 nominal species and 14 new to science but not yet described) was recently established at the Faculty of Sciences of Bizerte (Tunisia). Capacity building of next generation of African taxonomists have been carried out at level of both traditional and molecular taxonomy (DNA barcoding and next-generation sequencing [NGS]), but they need to be implemented. Indeed, the integration of these two approaches appears crucial to overcome lack of information on the taxonomy, ecology, and biodiversity of marine nematodes from African coastal waters.

8.
Zootaxa ; 3972(3): 407-18, 2015 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-26249500

RESUMO

Craspodema reflectans, erected by Gerlach 1964, is here re-described from some specimens recently found in the Maldivian archipelago and the implication of the new findings for the taxonomy of the Craspodema genus is discussed. Accordingly, an emended diagnosis of Craspodema genus and C. reflectans species are proposed. New data are also provided with the aid of the confocal laser scanning microscopy, using the natural fluorescence of the nematodes. The approach described here lays new foundations for the study of Museum collection material and it may be decisive for capture of new morphological details.


Assuntos
Nematoides/anatomia & histologia , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Ecossistema , Feminino , Masculino , Microscopia Confocal , Nematoides/classificação , Nematoides/crescimento & desenvolvimento , Tamanho do Órgão
9.
Zootaxa ; 3881(6): 501-12, 2014 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-25543649

RESUMO

A new species from the family Chromadoridae is described from samples collected during Dr Mortensen's Pacific Expedition 1914-16 to Honolulu, Hawaii. Parapinnanema hawaiiensis sp. nov. is characterized by a low c' ratio and especially by a peculiar complex morphology of the median part of the gubernaculum. An updated and modified key to all the valid species of Parapinnanema is proposed.


Assuntos
Nematoides/anatomia & histologia , Nematoides/classificação , Oceanos e Mares , Animais , Hawaii
10.
Environ Monit Assess ; 180(1-4): 325-44, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21120690

RESUMO

Many coastal areas have served as repositories of different anthropogenic and naturally induced organic material and nutrients. The major sources thereof are riverine inputs which strongly influence the spatial and temporal distribution of benthic communities. In this study, the benthic foraminiferal, meiofaunal, and macrofaunal colonies in front of three rivers in a poorly known, but environmentally valuable, area of the Central Adriatic Sea have been examined concurrently. The physico-chemical parameters of bottom water and sediment characteristics were determined in order to characterize both the sediment-water interface and the benthic environments. Although changes in the biota are neither univocal nor unidirectional, a moderate influence of riverine input on the different communities' components can be inferred. The most affected taxa are foraminifera and copepods and, to a lesser extent, meiofaunal polychaetes and platyhelminthes. These results are also tested by the ABC curves, which reveal that the macrofaunal communities closest to the river mouths are moderately disturbed. This integrated investigation documents, for the first time, how benthic communities can be used as an early warning indicator with which to monitor the health quality of a coastal ecosystem.


Assuntos
Organismos Aquáticos/classificação , Biodiversidade , Ecossistema , Invertebrados/classificação , Animais , Organismos Aquáticos/crescimento & desenvolvimento , Monitoramento Ambiental , Foraminíferos/classificação , Foraminíferos/crescimento & desenvolvimento , Invertebrados/crescimento & desenvolvimento , Itália , Mar Mediterrâneo , Platelmintos/classificação , Platelmintos/crescimento & desenvolvimento , Poliquetos/classificação , Poliquetos/crescimento & desenvolvimento , Água do Mar/química , Estresse Fisiológico , Poluentes da Água/análise
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