Recent changes in macroalgae distribution patterns in the Orbetello lagoon (Italy)

This study related recent distribution changes in seven macroalgae taxa (Acetabularia acetabulum, Chaetomorpha linum, Cladophora sp., Gracilariopsis longissima, Spyridia sp., Ulva laetevirens, Valonia aegagrophyla) to spatial (basin) and temporal (time) trophic differences in a meso-eutrophic Mediterranean coastal lagoon (Orbetello, Italy). In July 2003 and July 2009, the coverage percentage (CP) of each considered taxon was measured in 38 stations equally distributed in the Western and Eastern lagoon basins. All data were analysed using SURFER v8.0 software along with ANOVA, ANOSIM and multivariate analyses to produce geostatistical spatial distribution maps and to estimate statistical probabilities for "basin" and "time" factors. Data from this study were integrated with data on phanerogams reported by Giovani et al. (2010)to evaluate changes occurring at a functional group level from 2003-2009 using the Ecological Evaluation Index (EEI). Observed macroalgae changes may have been due to lagoon management activities performed during the study period. The removal of direct nitrate inputs seems to have forced specie-specific shifts that were highly significant only in the Western basin. Statistically significant differences at the taxon level have been indicated for Spyridia sp. (basin and time) and Cladophora sp. (time) taxa. Other non-significant changes included a rarefaction of Chaetomorpha linumin the Western basin and Spyridia sp. in the Eastern basin, and an increase of Gracilariopsis longissima, C. linum and Valonia aegagrophyla in the Eastern basin. EEI application indicated a general improvement in water quality due to management measures applied in Western basin, whereas the Eastern basin evidences stability/slight degradation from 2003-2009

Spatial and temporal variations of nutrients and chlorophyll a in a Mediterranean coastal lagoon: Varano lagoon, Italy

The purpose of this paper is to assess the present status of a Mediterranean lagoon (Varano lagoon, Italy), basing on nutrient and chlorophyll a data. A water sampling in Varano lagoon was performed at 7 fixed stations from February 2004 to July 2005, collecting surface water samples to analyse ammonia, nitrite, nitrate, soluble reactive phosphorus (SRP) and soluble reactive silica (SRSi), chlorophyll a (chl a) and total suspended solids (TSS). Spatial and temporal distributions of chemical and biological parameters in Varano lagoon were examined to accomplish the goal of this study. Statistical tests were used to investigate the correlations between analysed variables and to characterize, from a spatial and temporal point of view, the lagoon in relation to each variable. Ammonia and nitrate did not showed good correlation (P<0.05). SRP was not correlated with any nutrient (only with Chl a, P<0.05). The seasonal distribution show a random pattern for soluble reactive phosphorus with relatively low mean concentrations (0.16 ± 0.03 µM) and a well-defined seasonal pattern for nitrate, with the highest mean value (34.44 ± 10.18 µM) recorded in the wet season (February 2004) and a high spatial variability. The most homogeneous chl a values were observed in both autumn and winter seasons with averages of about 1-1.5 µg . L-1; in contrast, higher mean values (5.50 µg . L-1 ) were recorded in July 2005. The ratio between the dissolved inorganic nitrogen species and SRP (N/P) in Varano lagoon was constantly high and it varied seasonally from about 300:1 during rainy seasons to 60-90:1 during dry seasons. High values of the N/P ratio in autumn and winter were accompanied by an increase in total N implying an input of nitrogen to the system probably associated with rainfall. The high fluctuation in the various chemical parameters in the lagoon during the rainy season suggested that this is the period of large variability, in which environmental processes as marine waters, freshwaters and wastewaters represent inputs that determine the spatial behaviour of the system

Occurrence of POPs in sediments and tissues of European eels (Anguilla anguilla L.) from two Italian lagoons: Varano and Orbetello

Total levels of persistent organic pollutants (polychlorinated biphenyls, organochlorine pesticides,and polycyclic aromatic hydrocarbons) in sediments and edible tissues (muscle and liver) from a fish species of great local commercial interest (Anguilla anguilla L., yellow phase) were determined in Varano and Orbetello lagoons, Italy. The aim of this study was to improve knowledge on relationships occurring among levels of chemicals in sediments and fish tissues relating them reciprocally and to different intensities of human pressure. Studied ecosystems were selected due to the notable scientific knowledge acquired by previous detailed research on meteorology, geomorphology, hydrodynamics, types and distribution of local factors linked to different sources of human-made pollution. Samplings were performed in July 2009 according to a logic model based on a priori defined factors of interest and obtained results were statistically analysed in order to evaluate the significance of observed data segregation related to the selected factors. Concerning levels measured in sediments, significant differences were observed between lagoons in terms of ƩPAHs and ƩOCPs. According to National and international recognised sediment quality guidelines, results evidenced the occurrence of non-critical POPs values in sediments. Results on sediments are associated to very high levels in eel\u27s tissues. Concerning eels, Orbetello lagoon is characterized by significant higher values of ƩOCPs than Varano, evidencing the presence of an important OCPs local source. Different human pressure levels produce significant differences in both sediments and eel\u27s tissues in Varano and Orbetello lagoons

Litter in alien species of possible commercial interest: The blue crab (Callinectes sapidus Rathbun, 1896) as case study

Marine litter levels were measured in the stomach contents, hepatopancreas, and gonad tissues of crustacea decapod (Callinectes sapidus Rathbun, 1896; n\ua0=\ua06), a widespread alien species affecting the Lesina lagoon. Results highlight a mean of 2.5 (SD\ua0=\ua01.6) items/animal and indicate the presence of metals fragments (13%) and plastics (13% PE; 6.7% PET) in the stomach contents of collected individuals. No microplastic particles were detected in the hepatopancreas or in muscle tissue, while microplastic fibres (nylon, rayon, polyester) were found present in female specimen gonads. The presence of synthetic fibres in the investigated species reflects the relative contamination level in this habitat type and suggests that the blue crab could be considered a model organism for evaluating the contamination status of the study area

Resistance and resilience of ecosystem descriptors and properties to dystrophic events: a study case in a Mediterranean lagoon

Mediterranean lagoons are naturally exposed, during the dry season, to dystrophic and hypoxic events determining dis-equilibrium conditions along temporal and spatial scales, which are linked to metabolism and life cycle of the biotic components. In summer 2008, Lesina lagoon (SE Italian coastline) was interested by a geographically localized dystrophic crisis which affected up to 8% of the total lagoon surface. Temporal dynamics of principal descriptors of abiotic (water, sediment) and biotic (phytoplankton, benthic macroinvertebrate) compartments have been followed during the 2008 by collecting data inside stressed and control lagoon areas before a dystrophic event and in the six months after the dystrophic event. The aim of the study was to analyse the pathways of ecosystem responses to dystrophic stress, searching for the characteristic scales of ecosystem compartment resistance and resilience. The characteristic time-scale of abiotic and biotic component time responses varied from days, for the selected markers of the water column, to year, for the benthic ones. Short-term biotic and abiotic responses in the water column were strongly coupled while biotic and abiotic responses at the sediment level were remarkably un-coupled. Dynamics and recovery time of water column and benthic components do not match in Lesina following the dystrophic crisis, highlighting an intrinsic individualistic behavior within the lagoon community driving ecosystem processes and ecosystem level responses. Taxonomic and non-taxonomic descriptors of both phytoplankton and benthic macroinvertebrates showed different response patterns as early warning signals and overall resilience. The emphasized differences in the stability components, i.e., resistance and resilience, of water column and sediment abiotic and biotic characteristics as well as of taxonomic and non-taxonomic descriptors has key implication in planning monitoring strategies and programs for transitional waters in the Mediterranean and Black Sea EcoRegions

Trophic and Microbial Patterns in the Ross Sea Area (Antarctica): Spatial Variability during the Summer Season

In open regions of the Ross Sea, the role of the microbial community in the turnover of organic matter has scarcely been investigated; indeed, very little is known on how microbial distribution and functional diversity respond to environmental conditions and hydrographic structures. During the austral summer of 2017, two pelagic areas of the Ross Sea [the Drygalski Ice Tongue and the nearby Terra Nova Bay polynya (A area), and the continental Shelf Break area near Cape Adare (C area)] were studied at selected depths [surface, Deep Chlorophyll Maximum (DCM), Circumpolar Deep Water (CDW), deep waters]. Trophic properties [nutrient concentrations, particulate (POC), dissolved organic carbon (DOC) and its optically significant fraction (CDOM) were measured, together with the main hydrological variables. Microbial community abundance [total prokaryotes, living, dead, and actively respiring fraction, high- and low nucleic acid cells (HNA and LNA), picoand nano-eukaryotes, culturable heterotrophic bacteria], composition, and metabolism (as whole community and as isolated bacteria) were also assessed. Through a multidisciplinary dataset, this study highlighted the variable response of microbial abundance, diversity, and metabolism of the microbial community to the changing local environmental conditions of the Ross Sea. Different forces, such as organic matter inputs (mostly of detrital nature) released from the Drygalski glacier in the A area, and a coastal-to-offshore gradient in the C area, coexisted within this extreme ecosystem. This resulted in a significant spatial segregation of the edaphic parameters, and of the microbial community distribution and metabolic activity patterns

Marine litter in stomach content of small pelagic fishes from the Adriatic Sea: sardines (Sardina pilchardus) and anchovies (Engraulis encrasicolus)

Marine litter impacts oceans and affects marine organisms, representing a potential threat for natural stocks of pelagic fish species located at the first levels of the marine food webs. In 2013\u20132014, on a seasonal basis, marine litter and microplastics in stomach contents from Sardinia pilchardus and Engraulis encrasicolus were evaluated. Selected species are plankitivores of great ecological and commercial importance in the Adriatic Sea. Collected data were correlated to possible factors able to affect ingested levels as well as species, season of sampling, biometry and sex of animals. Almost all tested samples (80 organisms for each species) contained marine litter (over 90% of samples from both species) and also microplastics; while any meso- or macroplastics were recorded. On average, recorded items were as follows: 4.63 (S. plichardus) and 1.25 (E. encrasicolus) per individual. Sardines evidenced a higher number ofmicroplastics characterised by a smaller size than those recorded in anchovies. For sardines, sex, Gastro Somatic Index and sampling season showed negligible effects on the number of ingested litter; conversely, anchovies showed differences related with both sex of animals and dominant colour of ingested materials with prevalence for black and blue colours

ASSESSMENT OF MACROZOOBENTHIC DISTRIBUTION IN THE MANFREDONIA GULF (EASTERN MEDITERRANEAN)

Soft bottom macrozoobenthic distribution, as well as its composition, biomass and diversity were studied at 9 stations in the Gulf of Manfredonia. Polychaeta were numerically the dominant component (71%), followed by Crustacea (21%) and Bivalvia (2%). The highest biodiversity was observed at the stations in near-shore of the study area

Modelling effective choral conducting education through an exploration of example teaching and learning in England

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