Monitoring deep Mediterranean rhodolith beds

1. The protocols available for sampling and monitoring shallow subtidal rhodolith beds (RBs) are inadequate for the deep Mediterranean analogues, and need calibration in order to attain comparable results. 2. After reviewing the present knowledge of the peculiarities of Mediterranean RBs, and in the framework of the ongoing international effort for their conservation, a two-step approach is suggested for their definition, identification, delimitation, description, and monitoring. 3. Regional mapping should be improved, and RBs should be identified and delimited as those areas of the sea floor with >10% cover of live rhodoliths over a minimum surface of 500 m2, on 1:10000 scale. More detailed scales (at least 1:1000) should be used for monitoring selected RBs, in order to detect significant changes through time. 4. Beside location and areal extent, the description of RBs should include the occurrence of macroscopic sedimentary structures of the sea floor, thickness of live cover, mean percentage cover of live thalli and surface live/dead ratio, cover of dominant morphologies of rhodoliths (simplified on a ternary diagram), and volumetrically important calcareous algal species. 5. For the purpose of assessment of the ecological status and the evaluation of human-induced impacts, quantitative data about community composition are required. The comparative assessment of ecological status and the identification of RBs of high conservation value for special protection should consider the natural geographic and seasonal/annual variability of RBs

Calcareous Bio-Concretions in the Northern Adriatic Sea: Habitat Types, Environmental Factors that Influence Habitat Distributions, and Predictive Modeling

Habitat classifications provide guidelines for mapping and comparing marine resources across geographic regions. Calcareous bio-concretions and their associated biota have not been exhaustively categorized. Furthermore, for management and conservation purposes, species and habitat mapping is critical. Recently, several developments have occurred in the field of predictive habitat modeling, and multiple methods are available. In this study, we defined the habitats constituting northern Adriatic biogenic reefs and created a predictive habitat distribution model. We used an updated dataset of the epibenthic assemblages to define the habitats, which we verified using the fuzzy k-means (FKM) clustering method. Redundancy analysis was employed to model the relationships between the environmental descriptors and the FKM membership grades. Predictive modelling was carried out to map habitats across the basin. Habitat A (opportunistic macroalgae, encrusting Porifera, bioeroders) characterizes reefs closest to the coastline, which are affected by coastal currents and river inputs. Habitat B is distinguished by massive Porifera, erect Tunicata, and noncalcareous encrusting algae (Peyssonnelia spp.). Habitat C (non-articulated coralline, Polycitor adriaticus) is predicted in deeper areas. The onshore-offshore gradient explains the variability of the assemblages because of the influence of coastal freshwater, which is the main driver of nutrient dynamics. This model supports the interpretation of Habitat A and C as the extremes of a gradient that characterizes the epibenthic assemblages, while Habitat B demonstrates intermediate characteristics. Areas of transition are a natural feature of the marine environment and may include a mixture of habitats and species. The habitats proposed are easy to identify in the field, are related to different environmental features, and may be suitable for application in studies focused on other geographic areas. The habitat model outputs provide insight into the environmental drivers that control the distribution of the habitat and can be used to guide future research efforts and cost-effective management and conservation plans

First freshwater coralline alga and the role of local features in a major biome transition

Coralline red algae are significant components of sea bottom and up to now considered as exclusively marine species. Here we presentthe first coralline alga from a freshwater environment, found in theCetina River (Adriatic Sea watershed).The alga is fully adapted to freshwater, as attested by reproductive structures, sporelings, and an inability to survive brackish conditions. Morphological and molecular phylogenetic analyses revealthe species belongs to Pneophyllum and is described as P. cetinaensis sp. nov.The marine-freshwatertransition most probably occurred during the last glaciation. The brackish-water ancestor was preadapted to osmotic stress and rapid changes in water salinity and temperature.The particular characteristics ofthe karst Cetina River, such as hard water enriched with dissolved calcium carbonate and a pH similarto the marine environment, favoured colonization ofthe river by a marine species.The upstream advance and dispersal is facilitated by exceptionally pronounced zoochory by freshwater gastropods. Pneophyllum cetinaensis defies the paradigm of Corallinales as an exclusively marine group

Gene expression response of the alga Fucus virsoides (Fucales, Ochrophyta) to glyphosate solution exposure

Fucus virsoides is an ecologically important canopy-forming brown algae endemic to the Adriatic Sea. Once widespread in marine coastal areas, this species underwent a rapid population decline and is now confined to small residual areas. Although the reasons behind this progressive disappearance are still a matter of debate, F. virsoides may suffer, like other macroalgae, from the potential toxic effects of glyphosate-based herbicides. Here, through a transcriptomic approach, we investigate the molecular basis of the high susceptibility of this species to glyphosate solution, previously observed at the morphological and eco-physiological levels. By simulating runoff event in a factorial experiment, we exposed F. virsoides to glyphosate (Roundup\uae 2.0), either alone or in association with nutrient enrichment, highlighting significant alterations of gene expression profiles that were already visible after three days of exposure. In particular, glyphosate exposure determined the near-complete expression shutdown of several genes involved in photosynthesis, protein synthesis and stress response molecular pathways. Curiously, these detrimental effects were partially mitigated by nutrient supplementation, which may explain the survival of relict population in confined areas with high nutrient inputs. Our results show that glyphosate impairs the expression of genes involved in photosynthesis and protein synthesis in F. virsoides

Quality Difference in Craniofacial Pain of Cardiac vs. Dental Origin

Craniofacial pain, whether odontogenic or caused by cardiac ischemia, is commonly referred to the same locations, posing a diagnostic challenge. We hypothesized that the validity of pain characteristics would be high in assessment of differential diagnosis. Pain quality, intensity, and gender characteristics were assessed for referred craniofacial pain from dental (n = 359) vs. cardiac (n = 115) origin. The pain descriptors “pressure” and “burning” were statistically associated with pain from cardiac origin, while “throbbing” and “aching” indicated an odontogenic cause. No gender differences were found. These data should now be added to those craniofacial pain characteristics already known to point to acute cardiac disease rather than dental pathology, i.e., pain provocation/aggravation by physical activity, pain relief at rest, and bilateralism. To initiate prompt and appropriate treatment, dental and medical clinicians as well as the public should be alert to those clinical characteristics of craniofacial pain of cardiac origin

The response of the algae Fucus virsoides (Fucales, Ochrophyta) to Roundup® solution exposure: A metabolomics approach

8noGlyphosate, as a broad-spectrum herbicide, is frequently detected in water and several studies have investigated its effects on several freshwater aquatic organisms. Yet, only few investigations have been performed on marine macroalgae. Here, we studied both the metabolomics responses and the effect on primary production in the endemic brown algae Fucus virsoides exposed to different concentration (0, 0.5, 1.5 and 2.5 mg L−1) of a commercial glyphosate-based herbicide, namely Roundup®. Our results show that Roundup® significantly reduced quantum yield of photosynthesis (Fv/Fm) and caused alteration in the metabolomic profiles of exposed thalli compared to controls. Together with the decrease in the aromatic amino acids (phenylalanine and tyrosine), an increase in shikimate content was detected. The branched-amino acids differently varied according to levels of herbicide exposure, as well as observed for the content of choline, formate, glucose, malonate and fumarate. Our results suggest that marine primary producers could be largely affected by the agricultural land use, this asking for further studies addressing the ecosystem-level effects of glyphosate-based herbicides in coastal waters.partially_openopenFelline, Serena; Del Coco, Laura; Kaleb, Sara; Guarnieri, Giuseppe; Fraschetti, Simonetta; Terlizzi, Antonio; Fanizzi, Francesco Paolo; Falace, AnnalisaFelline, Serena; Del Coco, Laura; Kaleb, Sara; Guarnieri, Giuseppe; Fraschetti, Simonetta; Terlizzi, Antonio; Fanizzi, Francesco Paolo; Falace, Annalis

Cultivation of Gongolaria barbata (Fucales, Phaeophyceae) with a seaweed-derived biostimulant in order to improve photophysiological fitness and promote fertility to advance the restoration of marine macroalgal forests

As a result of several anthropogenic factors, Cystoseira sensu lato forests have declined or become regionally extinct in many coastal regions of the Mediterranean. Given the low natural recovery of lost populations, research efforts have been encouraged to develop sustainable and efficient restoration of macroalgal forests on a large scale. By promoting growth and fertility of collected thallus branches under controlled laboratory conditions, the availability of seedlings for restoration could be ensured without jeopardizing natural populations. Here we investigated the effect of a commercial algal biostimulant (AlgatronCifo (R)) on the photophysiology, growth and fertility of Gongolaria barbata (Stackhouse) Kuntze (Fucales, Phaeophyceae). In a factorial laboratory experiment, two different temperatures (10 oC and 14 degrees C) and two culture media [i.e. seawater (SW) and Algatron (AT)] were tested. The photosynthetic performance of G. barbata doubled after three weeks of culture with AT, while it decreased by 25% when cultivated in SW. The highest photosynthetic performance and growth were achieved at 14oC with AT, where fertile receptacles also developed, followed by seedling settlements. The thalli cultured in AT had similar or better photosynthetic performance than the initial control thalli. AT-cultured thalli had a greater ability to quench energy via photochemical pathways (q(P)) than those from the SW, which on the contrary, had higher levels of non-photochemical responses (q(N), NPQ(max)). This limited photosynthetic performance was probably linked to the higher P-limitation experienced under that treatment. The algal biostimulant enhanced the physiological performance and induced fertility of G. barbata, demonstrating its valorization potential and setting a new path for improved restoration applications

Rhodolith beds heterogeneity along the apulian continental shelf (Mediterranean sea)

Rhodolith beds represent a key habitat worldwide, from tropical to polar ecosystems. Despite this habitat is considered a hotspot of biodiversity, providing a suite of ecosystem goods and services, still scarce quantitative information is available thus far about rhodolith beds occurrence and ecological role, especially in the Mediterranean Sea. This study reports the composition and patterns of distribution of rhodolith assemblages found in four study areas along ca. 860 km of coast in the Central Mediterranean Sea. These rhodolith beds were studied for the first time and significant differences at all spatial scales have been highlighted, documenting the high variability of this habitat. Rhodolith species composition, morphology and distribution have been discussed considering the potential role of environmental factors in driving these patterns. The need for improving their protection is discussed to complement present conservation and management initiatives, particularly in the frame of the EU Marine Strategy Framework Directive

Spatial patterns and drivers of benthic community structure on the northern Adriatic biogenic reefs

The northern Adriatic Sea (NAS) hosts numerous biogenic subtidal reefs that are considered biodiversity hotspots. Several studies have already investigated the origin and biodiversity of these reefs. However, many of them are still unexplored and further knowledge is needed for their conservation. Here, the spatial variability, epibenthic community structure, and environmental features that characterize these habitats were investigated. Fifteen randomly selected reefs were sampled between 2013 and 2017, including some remote sites that have never been studied before. A fuzzy k-means clustering method and redundancy analysis were used to find similarities among sites in terms of epibenthic assemblages and to model relationships with abiotic variables. The results showed that these reefs are highly heterogeneous in terms of species composition and geomorphological features. The results were also consistent with previous studies and highlighted three main types of benthic assemblages defined by the dominance of different organisms, mainly reflecting the coastal-offshore gradient: nearshore reefs, generally dominated by stress-tolerant species; reefs at a middle distance from the coast, characterized by sponges, non-calcareous encrusting algae and ascidians; offshore reefs, dominated by reef builders. However, distance from the coast was not the only factor affecting species distribution, as other local factors and environmental characteristics also played a role. This kind of biogenic reefs in temperate seas are still poorly known. The present work contributed to shed further light on these habitats, by complementing the results of previous studies on their natural diversity, highlighting the specificity of the epibenthic communities of NAS reefs and the need to improve current, still inadequate, conservation measures

Loss and Recovery Potential of Marine Habitats: An Experimental Study of Factors Maintaining Resilience in Subtidal Algal Forests at the Adriatic Sea

BACKGROUND: Predicting and abating the loss of natural habitats present a huge challenge in science, conservation and management. Algal forests are globally threatened by loss and severe recruitment failure, but our understanding of resilience in these systems and its potential disruption by anthropogenic factors lags well behind other habitats. We tested hypotheses regarding triggers for decline and recovery potential in subtidal forests of canopy-forming algae of the genus Cystoseira. METHODOLOGY/PRINCIPAL FINDINGS: By using a combination of historical data, and quantitative in situ observations of natural recruitment patterns we suggest that recent declines of forests along the coasts of the north Adriatic Sea were triggered by increasing cumulative impacts of natural- and human-induced habitat instability along with several extreme storm events. Clearing and transplantation experiments subsequently demonstrated that at such advanced stages of ecosystem degradation, increased substratum stability would be essential but not sufficient to reverse the loss, and that for recovery to occur removal of the new dominant space occupiers (i.e., opportunistic species including turf algae and mussels) would be required. Lack of surrounding adult canopies did not seem to impair the potential for assisted recovery, suggesting that in these systems recovery could be actively enhanced even following severe depletions. CONCLUSIONS/SIGNIFICANCE: We demonstrate that sudden habitat loss can be facilitated by long term changes in the biotic and abiotic conditions in the system, that erode the ability of natural ecosystems to absorb and recover from multiple stressors of natural and human origin. Moreover, we demonstrate that the mere restoration of environmental conditions preceding a loss, if possible, may be insufficient for ecosystem restoration, and is scarcely cost-effective. We conclude that the loss of complex marine habitats in human-dominated landscapes could be mitigated with appropriate consideration and management of incremental habitat changes and of attributes facilitating system recovery