Search results for "Bioindicator"
showing 10 items of 97 documents
Phytoplankton Reservoir Trophic Index (PRTI): a new tool for ecological quality studies
2019
The Phytoplankton Reservoir Trophic Index (PRTI), based on the relative abundance of phytoplankton in reservoirs, was applied to 62 reservoirs, all in the territorial division of the Ebro River Basin, Spain. We compared the results of the PRTI to the Carlson Trophic State Index (TSI), based on the concentration of chlorophyll a in an integrated water sample through the photic depth. The PRTI allows assessment of the trophic status of different reservoirs based on phytoplankton densities from an aliquot of a vertically integrated sample. The occurrence of each phytoplankton species in relation to eutrophication was derived from a canonical correspondence analysis between the phytoplankton sp…
Organic enrichment effects on a marine meiofauna community, with focus on Kinorhyncha
2016
Abstract Within the framework of a programme aimed at monitoring the impact of fish farming on the marine biota, we have had the opportunity to study the effect of the organic enrichment caused by the fish farm on meiofauna abundances and Kinorhyncha communities’ structure over two farming cycles. Up to now, studies on kinorhynchs have focussed mostly on the taxonomy, biogeography, and the ultrastructure, and, more recently, on the phylogenetic aspects of the taxon. Only few studies have dealt with the ecology of these creatures and studies focusing on the response of these animals to disturbances of anthropogenic origin are rare. The study took place in the Western Mediterranean and fauna …
Impact of sewage pollution on two species of sea urchins in the Mediterranean Sea (Cortiou, France): radial asymmetry as a bioindicator of stress.
2015
9 pages; International audience; BackgroundThe surroundings of the Cortiou sewage are among the most polluted environments of the French Mediterranean Sea (Marseilles, France). So far, no studies have precisely quantified the impact of pollution on the development of organisms in this area.MethodsWe used a fluctuating asymmetry (FA) measure of developmental instability (DI) to assess environmental stress in two species of radially symmetric sea urchins (Arbacia lixula and Paracentrotus lividus). For six sampling sites (Cortiou, Riou, Maire, East Maire, Mejean, and Niolon), levels of FA were calculated from continuous and discrete skeletal measures of ambulacral length, number of pore pairs …
CHANGES IN COLLEMBOLA RICHNESS AND DIVERSITY ALONG A GRADIENTOF LAND-USE INTENSITY : A pan European study
2006
Changes in Collembola richness and diversity along a land-use intensity gradient were studied in eight European countries (Portugal, Spain, France, Switzerland, Hungary, UK, Ireland and Finland). In each country a set of six 1 km2 land-use units (LUUs) were selected forming a gradient ranging from natural forest to agricultural dominated landscapes, passing through mixed-use ones. In addition to data on Collembola, detailed information regarding landscape diversity and structure was collected for each LUU. A total of 47,774 individuals were identified from 281 species. Collembola reacted not only to changes in the diversity of the landscape, but also to the composition of that diversity and…
Evaluating the presence of microplastics in striped dolphins (Stenella coeruleoalba) stranded in the Western Mediterranean Sea.
2020
Litter is a well-known problem for marine species; however, we still know little about the extent to which they're affected by microplastics. In this study, we analyse the presence of this type of debris in Western Mediterranean striped dolphins' intestinal contents over three decades. Results indicated that frequency was high, as 90.5% of dolphins contained microplastics. Of these microplastics, 73.6% were fibres, 23.87% were fragments and 2.53% were primary pellets. In spite of the high frequency of occurrence, microplastic amount per dolphin was relatively low and highly variable (mean ± SD = 14.9 ± 22.3; 95% CI: 9.58–23.4). Through FT-IR spectrometry, we found that polyacrylamide, typic…
Using Boops boops (osteichthyes) to assess microplastic ingestion in the Mediterranean Sea
2020
Abstract This study assesses microplastic ingestion in Boops boops at different geographical areas in the Mediterranean Sea. A total of 884 fish were caught at 20 coastal sites in Spain, France, Italy and Greece and analyzed using a common methodological protocol. Microplastics were found in 46.8% of the sampled fish, with an average number of items per individual of 1.17 ± 0.07. Filaments were the predominant shape type, while polyethylene and polypropylene were indicated by FTIR as the most common polymer types of ingested microplastics. The frequency of occurrence, as well as the abundance and proportion of types (size, shape, color and polymer) of ingested microplastics, varied among ge…
Evaluation and comparison of trace metal accumulation in different tissues of potential bioindicator organisms: Macrobenthic filter feedersStyela pli…
2016
Trace metal concentrations were measured in different tissues of Sabella spallanzanii, Styela plicata, and Mytilus galloprovincialis collected in the Termini Imerese Harbor (Sicily, Italy) to evaluate the potential use of these species as bioindicators. Higher bioaccumulation factors (BAFs) were calculated in the tube of S. spallanzanii, except for As, which had a higher BAF in the branchial crown of the same species. Regarding the other species analyzed, higher BAFs were found in the digestive gland of M. galloprovincialis. An exception was Pb, which was significantly more concentrated in the branchial basket and tunic of S. plicata. The BAFs calculated in the present study show that all t…
Descriptors of Posidonia oceanica meadows: Use and application
2005
This work benefited partly from the financial support of the European program ΓNTERREG IIIA Corsica, Sardinia. Tuscany
Environmental factors responsible for the gyrogonite formation by an endangered macroalga, Lychnothamnus barbatus, a fertility indicator of past and …
2019
Abstract Gyrogonites (calcified oospores) of charophytes are commonly used in palaeoecology. Although, the study of morphometry and gyrogonite production by extant charophytes is limited. This concerns the genus Lychnothamnus , frequent in the past but contemporarily represented only by L. barbatus , the rare and endangered species applied in assessment of water quality as a bioindicator of oligo-mesotrophic lakes. In this study two hypotheses were verified: (1) the length and width of L. barbatus gyrogonites increase with increasing depth; (2) at the deeper sites, L. barbatus produces more numerous gyrogonites compared to shallower lake areas. Gyrogonites were picked from L. barbatus thall…
Trace element storage capacity of sediments in deadPosidonia oceanicamat from a chronically contaminated marine ecosystem
2016
Posidonia oceanica mat is considered a long-term bioindicator of contamination. Storage and sequestration of trace elements and organic carbon (Corg) were assessed in dead P. oceanica mat and bare sediments from a highly polluted coastal marine area (Augusta Bay, central Mediterranean). Sediment elemental composition and sources of organic matter have been altered since the 1950s. Dead P. oceanica mat displayed a greater ability to bury and store trace elements and Corg than nearby bare sediments, acting as a long-term contaminant sink over the past 120?yr. Trace elements, probably associated with the mineral fraction, were stabilized and trapped despite die-off of the overlying P. oceanica…