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1.
Sci Total Environ ; 703: 135496, 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-31761368

RESUMO

Benthic macroinvertebrates are often used in ecological quality monitoring. However, due to the large number of samples and specimens, sample processing (sorting/identification) is a labor-intensive task that is susceptible to errors. These errors can consequently lead to biased assessment results. We conducted the first audit of the Greek National Water Monitoring program. Totally, 444 samples were sorted at the laboratory by primary sorters and macroinvertebrate identification was conducted mainly at family level by primary taxonomists, having different taxonomic expertise. The Percentage Sorting Efficiency (PSE), Percentage of Taxonomic Disagreement (PTD), and the Relative Percentage Difference (RPD) were calculated to determine differences between auditing stages. Control charts were used to determine the process changes of the personnel (sorting: PSE index and identification: PTD index) as a calibration check. Additionally, national ecological indices/metrics were calculated to identify how they are affected by errors. All samples except from one had PSE values higher than 90%. The most common overlooked families were Chironomidae, followed by Baetidae and Gammaridae due to their high abundances. Average values of the PTD index for the total number of samples was 5.75% and 1.86% in each phase, respectively. The PTD values decreased between the two phases due to the gained experience of primary taxonomists during the 1st phase. The average action control limit was 95% for the PSE values and 14% for the PTD values. Overall, our ecological quality results indicated that the sorting error was less important than the identification one as the latter may lead to different ecological quality classifications. Our results show that our auditing procedure is effective and increases the quality and accuracy of the sample analysis procedure. It also highlights that human error should not be neglected since it may affect the ecological quality results and especially the good/moderate boundary which leads to rehabilitation measures.


Assuntos
Monitoramento Ambiental/métodos , Invertebrados , Poluentes Químicos da Água/análise , Animais , Água Doce , Controle de Qualidade , Projetos de Pesquisa
2.
Zootaxa ; 4657(3): zootaxa.4657.3.5, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31716772

RESUMO

The morphology of the different stages (larva, pupa, male, and female) of Rhyacophila fasciata kykladica Malicky Sipahiler 1993 was examined as a basis for the description of the taxon. Morphological data were supplemented by molecular analysis of mitochondrial cytochrome C oxidase subunit I (mtCOI), which were compared with samples of the nominate subspecies Rhyacophila fasciata fasciata Hagen 1859, as well as with other new species in this group, Rhyacophila denticulata McLachlan 1879 and Rhyacophila sociata Navás 1916. Our results revealed genetic differences between all the taxa; therefore, a change of taxonomic status of R. fasciata kykladica to R. kykladica (stat. prom.) is proposed.


Assuntos
Holometábolos , Insetos , Animais , Ecologia , Feminino , Grécia , Larva , Masculino
3.
Environ Pollut ; 254(Pt B): 113057, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31454578

RESUMO

Olive mill wastewaters (OMW) discharging in river ecosystems cause significant adverse effects on their water chemistry and biological communities. We here examined the effects of OMW loads in four streams of a Mediterranean basin characterized by changing flow. The diatom and macroinvertebrate community structures were compared between upstream (control) and downstream (impacted) sites receiving OMW discharge. We also tested if effects occurred at the organism level, i.e. the occurrence of deformities in diatom valves, and the sediment toxicity on the midge Chironomus riparius. We evaluated these effects through a two-year analysis, at various levels of chemical pollution and dilution capacity. The impacted sites had high phenol concentrations and organic carbon loads during and after olive mill (OM) operation, and were characterized by higher abundances of pollution-tolerant diatom and macroinvertebrate taxa. Diatom valve deformities occurred more frequently at the impacted sites. The development of C. riparius was affected by phenolic compounds and organic carbon concentrations in the sediments. The similarity in the diatom and macroinvertebrate assemblages between control and impacted sites decreased at lower flows. Diatoms were more sensitive in detecting deterioration in the biological status of OMW receiving waterways than macroinvertebrates. Our results indicate that the negative effects of OMW extended to the whole benthic community, at both assemblage and organism level.


Assuntos
Monitoramento Ambiental , Olea , Águas Residuárias/química , Poluentes Químicos da Água/toxicidade , Biota , Diatomáceas , Ecossistema , Fenol/análise , Rios/química , Eliminação de Resíduos Líquidos , Águas Residuárias/análise , Poluentes Químicos da Água/análise
4.
Chemosphere ; 236: 124364, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31326755

RESUMO

Water is polluted by increasing activities of population and the necessity to provide them with goods and services that use water as a vital resource. The contamination of water due to heavy metals (HMs) is a big concern for humankind; however, global studies related to this topic are scarce. Thus, the current review assesses the content of HMs in surface water bodies throughout the world from 1994 to 2019. To achieve this goal, multivariate analyses were applied in order to determine the possible sources of HMs. Among the analyzed HMs in a total of 147 publications, the average content of Cr, Mn, Co, Ni, As and Cd exceeded the permissible limits suggested by WHO and USEPA. The results of the heavy metal pollution index, evaluation index, the degree of contamination, water pollution and toxicity load showed that the examined water bodies are highly polluted by HMs. The results of median lethal toxicity index showed maximum toxicity in As, Co, Cr and Ni in the surface water bodies. Results of ingestion and dermal pathways for adults and children in the current analyzed review showed that As is the major contaminant. Moreover, Cr, Ni, As and Cd showed values that could be considered as a high risk for cancer generation via the ingestion pathway as compared to the dermal route. It is recommended that remediation techniques such as the introduction of aquatic phytoremediation plant species and adsorbents should be included in land management plans in order to reduce human risks.


Assuntos
Monitoramento Ambiental/métodos , Metais Pesados/química , Poluentes Químicos da Água/química , Água/química , Humanos , Análise Multivariada
5.
Sci Total Environ ; 665: 290-299, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30772559

RESUMO

The environmental factors that determine species richness and community structure in running waters have long been studied, but how these factors hierarchically and/or interactively influence benthic communities remains unclear. To address this research gap, we identified the principal abiotic factors that determine the taxonomic composition and functionality of stream macroinvertebrate communities and explored possible hierarchical and/or interactive patterns. We analyzed a large dataset from Greek rivers, and compared multiple macroinvertebrate metrics and traits between perennial and intermittent watercourses during wet and dry periods. We found that macroinvertebrates were primarily influenced by two ecological gradients: (i) aquatic vegetation-conductivity; and (ii) water temperature-canopy cover. Macroinvertebrates in perennial rivers were mainly influenced by the first gradient, whereas in intermittent rivers both gradients were important. Taxonomic richness and diversity were higher and temporally stable within years in perennial rivers, whereas in intermittent rivers, these metrics peaked during early summer, before the onset of streambed desiccation. The two environmental gradients determined the taxonomic richness and diversity in both spring and summer; however, a clear influence of hydrological factors (wetted width, water depth, flow velocity and discharge) was observed only in the intermittent samples. We conclude that the benthic invertebrate taxonomic richness and diversity in highly variable environments is primarily determined by hydrological variation and ultimately fine-tuned by local habitat factors. As climate change scenarios predict severe modification of hydrological and local habitat factors, this study concludes that in river management, hydrological restoration should be prioritized over other local habitat factors by maintaining natural hydrological variability, to ensure aquatic community richness and diversity.


Assuntos
Organismos Aquáticos/fisiologia , Ecossistema , Monitoramento Ambiental , Invertebrados/fisiologia , Animais , Rios
6.
Zootaxa ; 4543(1): 145-150, 2019 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-30647319

RESUMO

This contribution aims in enhancing knowledge of the zoogeography of the freshwater shrimp fauna of Greece, based on field collections carried out from 2002-2016. A total of 167 specimens were collected from 25 locations in rivers, streams and lakes of the Greek peninsula and islands. Our study adds more localities with exclusive records of A. acheronensis/A. desmarestii in central- western Greece, where it was previously presumed that A. stankoi occurred. Furthermore, A. stankoi is now recorded for the first time in two rivers of eastern central Greece, as well as in a spring system of western Greece, being thus its westernmost record so far.


Assuntos
Decápodes , Palaemonidae , Animais , Grécia , Ilhas , Lagos , Rios
7.
Sci Total Environ ; 647: 1179-1187, 2019 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-30180326

RESUMO

The hydrological and biological complexity of temporary rivers as well as their importance in providing goods and services is increasingly recognized, as much as it is the vulnerability of the biotic communities in view of climate change and increased anthropogenic pressures. However, the effects of flow intermittency (resulting from both seasonal variations and rising hydrological pressure) and pollution on biodiversity and ecosystem functioning have been overlooked in these ecosystems. We explore the way multiple stressors affect biodiversity and ecosystem functioning, as well as the biodiversity-ecosystem functioning (B-EF) relationship in a Mediterranean temporary river. We measured diversity of benthic communities (i.e. diatoms and macroinvertebrates) and related ecosystem processes (i.e. resource use efficiency-RUE and organic matter breakdown-OMB) across a pollution and flow intermittency gradient. Our results showed decreases in macroinvertebrate diversity and the opposite trend in diatom assemblages, whereas ecosystem functioning was negatively affected by both pollution and flow intermittency. The explored B-EF relationships showed contrasting results: RUE decreased with higher diatom diversity, whereas OMB increased with increased macroinvertebrate diversity. The different responses suggest contrasting operating mechanisms, selection effects possibly driving the B-EF relationship in diatoms and complementarity effects driving the B-EF relationship in macroinvertebrates. The understanding of multiple stressor effects on diversity and ecosystem functioning, as well as the B-EF relationship in temporary rivers could provide insights on the risks affecting ecosystem functioning under global change.


Assuntos
Biodiversidade , Ecossistema , Monitoramento Ambiental , Animais , Invertebrados , Região do Mediterrâneo , Rios/química
8.
Zootaxa ; 4514(1): 97-106, 2018 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-30485956

RESUMO

The larva of Rhyacophila palmeni McLachlan 1879 is described, based on material from Greece and Kosovo. The diagnostic features of the species are discussed and illustrated, and some information on its ecology and distribution are included. In addition, diagnostic characters for larvae of the known Greek Rhyacophila species are provided.


Assuntos
Ecologia , Insetos , Animais , Grécia , Kosovo , Larva
9.
Zootaxa ; 4508(1): 85-100, 2018 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-30485998

RESUMO

Based on adults, mature pupae, and larvae sampled at the same sites on mainland Greece and on the Greek islands of Kerkyra (Corfu) and Crete, the previously unknown larval stages of Rhyacophila tsurakiana Malicky 1984, R. gudrunae Malicky 1972, and R. biegelmeieri Malicky 1984 could be associated and identified. This material enabled us to describe and illustrate the final instar larvae of these three species, and to extract reliable diagnostic characters updating the existing larval key to the Greek species of genus Rhyacophila Stephens 1836 (Karaouzas et.al. 2015). In the context of this key, R. tsurakiana (together with R. tristis Pictet 1834 and R. obtusa Klapálek 1894) lacks abdominal gills; the three species can be separated by the shape of the dorsal sclerite of abdominal segment IX and by anal proleg morphology. Rhyacophila gudrunae is the only Greek species so far where larvae are fitted with one four-filament gill on each body side of the abdomen. Finally, R. biegelmeieri has one tufted multifilament gill on each body side and can be separated from four other species sharing this gill morphology by coloration patterns and head widths; however, separation from R. nubila Zetterstedt 1840 and R. palmeni McLachlan 1879 is not yet possible. Rhyacophila tsurakiana and R. biegelmeieri are large-scale endemic caddisfly species of European Ecoregion 6 (Hellenic Western Balkan), whereas R. gudrunae is a micro-endemic species of this region and restricted to the island of Crete (Malicky 2005b; Graf et al. 2008).


Assuntos
Insetos , Animais , Brânquias , Grécia , Larva , Pupa
10.
Zootaxa ; 4504(2): 296-300, 2018 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-30486032

RESUMO

The larva of Hydropsyche perseus Malicky 2001, endemic species of Kerkyra Island (Corfu), Greece, is described for the first time. The diagnostic features of the species are described and illustrated, and some information regarding its ecology is included. In addition, a tabular key for larvae of the known Hydropsyche species of the Greek Islands is provided.


Assuntos
Insetos , Animais , Ecologia , Grécia , Ilhas , Larva
11.
Zootaxa ; 4382(2): 381-392, 2018 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-29689925

RESUMO

The larvae of Hydropsyche cetibeli Malicky Sipahiler 1993 from the Aegean, Hydropsyche mostarensis Klapálek 1898, endemic of the Balkan Peninsula, and Hydropsyche pygmalion Malicky 2001 endemic of Serifos Island (Cyclades, Greece) are described for the first time. The diagnostic features of the species are described and illustrated, and some information regarding their ecology is included. In addition, a tabular key for larvae of the known Hydropsyche species of Greece and the Aegean Islands is included.


Assuntos
Insetos , Distribuição Animal , Animais , Península Balcânica , Grécia , Ilhas , Larva
12.
Sci Total Environ ; 618: 1591-1604, 2018 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-29054662

RESUMO

Temporary rivers are dynamic and complex ecosystems that are widespread in arid and semi-arid regions, such as the Mediterranean. Biotic communities adapted in their intermittent nature could withstand recurrent drought events. However, anthropogenic disturbances in the form of water stress and chemical pollution challenge biota with unpredictable outcomes, especially in view of climate change. In this study we assess the response of the biotic community of a temporary river to environmental stressors, focusing on water stress and pollution. Towards this aim, several metrics of four biotic groups (diatoms, macrophytes, macroinvertebrates and fish) were applied. All biotic groups responded to a pollution gradient mainly driven by land use, distinct functional groups of all biota responded to water stress (a response related to the rheophilic nature of the species and their resistance to shear stress), while the combined effects of water stress and pollution were apparent in fish. Biotic groups presented a differential temporal response to water stress, where diatom temporal assemblage patterns were explained by water stress variables of short-time response (15days), while the responses of the other biota were associated to longer time periods. There were two time periods of fish response, a short (15days) and a long-time response (60-75days). When considering management decisions, our results indicate that, given the known response of river biota to pollution, biomonitoring of temporary rivers should also involve metrics that can be utilized as early warnings of water stress.


Assuntos
Organismos Aquáticos/fisiologia , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Animais , Mudança Climática , Diatomáceas/fisiologia , Ecossistema , Peixes/fisiologia , Invertebrados/fisiologia , Rios , Poluentes Químicos da Água/toxicidade , Poluição da Água
13.
Zootaxa ; 4329(1): 73-80, 2017 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-29242482

RESUMO

In this paper, we present a description of the previously unknown larva of Agapetus episkopi Malicky 1972 (Trichoptera: Glossosomatidae). Information on the morphology of the larvae is given and the most important diagnostic features are photographed. As a species of subfamily Agapetinae Martynov 1913, A. episkopi larvae belong to the group of species with sclerites present on the pro-, meso-, and metanota. Because lateral setae on abdominal segment III are lacking and the larval case lacks a sand collar at its base, A. episkopi keys with Agapetus laniger Pictet 1834 and Agapetus delicatulus McLachlan 1884. Within this trio, each of the latter two species can be easily separated from A. episkopi by the coloration pattern of their frontoclypeus, where a pale central area is present, and by the presence of only one lateral seta on each side of abdominal segment I. With respect to distribution, A. episkopi has been recorded from European Ecoregion 6 (= Hellenic western Balkan region) and Asia Minor. In addition, ecological characteristics are briefly discussed, and a key to the known glossosomatid larvae of European Ecoregion 6 is included.


Assuntos
Insetos , Animais , Ásia , Península Balcânica , Ecologia , Larva
14.
Sci Total Environ ; 603-604: 639-650, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-28667932

RESUMO

Water stress is a key stressor in Mediterranean intermittent rivers exacerbating the negative effects of other stressors, such as pollutants, with multiple effects on different river biota. The current study aimed to determine the response of macroinvertebrate and fish assemblages to instream habitat and water chemistry, at the microhabitat scale and at different levels of water stress and pollution, in an intermittent Mediterranean river. Sampling was conducted at high and low summer discharge, at two consecutive years, and included four reaches that were targeted for their different levels of water stress and pollution. Overall, the macroinvertebrate fauna of Evrotas River indicated high resilience to intermittency, however, variation in community structure and composition occurred under acute water stress, due to habitat alteration and change in water physico-chemistry, i.e. water temperature increase. The combined effects of pollution and high water stress had, however, pronounced effects on species richness, abundance and community structure in the pollution impacted reach, where pollution sensitive taxa were almost extirpated. Fish response to drought, in reaches free of pollution, consisted of an increase in the abundance of the two small limnophilic species, coupled with their shift to faster flowing riffle habitats, and a reduction in the abundance of the larger, rheophilic species. In the pollution impacted reach, however, the combination of pollution and high water stress led to hypoxic conditions assumed to be the leading cause of the almost complete elimination of the fish assemblage. In contrast, the perennial Evrotas reaches with relatively stable physicochemical conditions, though affected hydrologically by drought, appear to function as refugia for fish during high water stress. When comparing the response of the two biotic groups to combined acute water stress and pollution, it is evident that macroinvertebrates were negatively impacted, but fish were virtually eliminated under the two combined stressors.


Assuntos
Monitoramento Ambiental , Peixes , Invertebrados , Rios/química , Poluição da Água/efeitos adversos , Animais , Ecossistema , Grécia , Estresse Fisiológico , Temperatura
15.
Zootaxa ; 4200(3): zootaxa.4200.3.4, 2016 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-27988631

RESUMO

The previously unknown larva of Wormaldia asterusia Malicky 1972 is described. The diagnostic features of the species are listed and illustrated and some information on its ecology is included. An update on the knowledge of the genus in Greece is given and a larval key of the known West Palearctic Wormaldia species is provided.


Assuntos
Insetos/classificação , Distribuição Animal , Animais , Feminino , Grécia , Insetos/anatomia & histologia , Larva/anatomia & histologia , Larva/classificação , Masculino , Especificidade da Espécie
16.
Zootaxa ; 4189(3): zootaxa.4189.3.9, 2016 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-27988751

RESUMO

The hitherto unknown larva of Lepidostoma doehleri Malicky 1976 is described. The diagnostic features of the species are listed and illustrated, and some information on its ecology is included. In addition, diagnostic characters for the larvae of the known Lepidostoma species occurring in Greece are provided.


Assuntos
Insetos/anatomia & histologia , Insetos/crescimento & desenvolvimento , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Ecossistema , Feminino , Grécia , Insetos/classificação , Larva/anatomia & histologia , Larva/classificação , Larva/crescimento & desenvolvimento , Masculino , Tamanho do Órgão
17.
Zootaxa ; 4097(4): 557-66, 2016 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-27394566

RESUMO

The larvae of Hydropsyche rhadamanthys Malicky 2001 and Hydropsyche sarpedon Malicky 2001, endemics of Crete Island, Greece, are described for the first time. The diagnostic features of the species are described and illustrated, and some information regarding their ecology is included. In addition, diagnostic characters for larvae of the known Aegean Hydropsyche species are provided.


Assuntos
Insetos/crescimento & desenvolvimento , Larva/anatomia & histologia , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Ecossistema , Feminino , Grécia , Insetos/anatomia & histologia , Insetos/classificação , Insetos/fisiologia , Ilhas , Larva/classificação , Larva/crescimento & desenvolvimento , Larva/fisiologia , Masculino , Tamanho do Órgão
18.
Zootaxa ; 4111(4): 301-33, 2016 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-27395093

RESUMO

An overview of the Greek stonefly (Plecoptera) fauna is presented as an annotated index of all available published records. These records have resulted in an updated species list reflecting current taxonomy and species distributions of the Greek peninsula and islands. Currently, a total of 71 species and seven subspecies belonging to seven families and 19 genera are reported from Greece. There is high species endemicity of the Leuctridae and Nemouridae, particularly on the Greek islands. The endemics known from Greece comprise thirty species representing 42% of the Greek stonefly fauna. The remaining taxa are typical Balkan and Mediterranean species.


Assuntos
Insetos/classificação , Animais , Lista de Checagem , Curadoria de Dados , Feminino , Grécia , Masculino
19.
Mol Phylogenet Evol ; 100: 322-332, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27118180

RESUMO

The Potomida genus (Bivalvia, Unionida) has a Circum-Mediterranean distribution and like other freshwater mussel species, its populations have suffered dramatic declines. Although this genus is currently considered as monotypic, it has a long history of taxonomic revisions and presently many aspects of its systematics and evolutionary history are unclear. We sampled a total of 323 individuals from 39 different sites across the Potomida genus distribution, and sequenced two mitochondrial (16S rDNA and Cytochrome c Oxidase Subunit I) and one nuclear (28S rDNA) genes to clarify its phylogeny and phylogeographic history. Our results show that the genus includes two well-supported clades, one comprising solely the western Mediterranean species Potomida littoralis, and the other including two eastern Mediterranean species, the Greek endemic P. acarnanica and the Anatolian and Middle Eastern P. semirugata. We suggest that Potomida started radiating during the upper Miocene, and that both vicariance and dispersal events shaped the diversification and distribution of the genus along the Mediterranean region. P. littoralis is further divided in two mitochondrial lineages, one restricted to Europe and the other occurring mostly in North Africa. Moreover, some European basins present both lineages in sympatry. The conservation status of the three recognized species should be reevaluated, particularly P. acarnanica, since it is restricted to two Greek river basins presenting a high risk of extinction. Overall, our results clarify some important gaps in knowledge concerning the phylogeny, phylogeography and evolution of the Potomida genus in the Mediterranean region with important taxonomical, ecological and conservational implications.


Assuntos
Bivalves/genética , Animais , Sequência de Bases , DNA Mitocondrial/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Evolução Molecular , Água Doce , Especiação Genética , Região do Mediterrâneo , Tipagem de Sequências Multilocus , Filogenia , Filogeografia , RNA Ribossômico 16S/genética
20.
Zootaxa ; 4057(3): 444-50, 2015 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-26701493

RESUMO

The previously unknown larva of Rhyacophila balcanica Radovanovic 1953 is described. The diagnostic features of the species are listed and illustrated and some information on its ecology and distribution is included. In addition, diagnostic characters for larvae of the known Greek Rhyacophila species are provided.


Assuntos
Insetos/classificação , Larva/anatomia & histologia , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Ecossistema , Feminino , Insetos/anatomia & histologia , Insetos/crescimento & desenvolvimento , Larva/classificação , Larva/crescimento & desenvolvimento , Masculino , Tamanho do Órgão
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