86 research outputs found
The impact assessment of thermal pollution on subtidal sessile assemblages: a case study from Mediterranean rocky reefs
Coastal power plants generally use seawater as cooling fluid, discharging heated waters into the sea after the cooling process. The ensuing increase in seawater temperature could affect the marine biota in the nearby areas, causing alterations at different level of biological organization, from individuals to populations and assemblages. In the Mediterranean Sea, few attempts have been made to assess the effects of this point sources of thermal pollution, especially on rocky habitats. Here, we investigated the putative impact of a thermal effluent from one of the largest European coal-fired coastal power plants on sessile assemblages of subtidal rocky reefs. Sessile assemblages on rocky substrates were photographically sampled at one location near the effluent (I), and at two control locations (Cs) virtually unaffected by thermal discharge. An asymmetrical after-control impact experimental design was employed to test the hypothesis that the thermal discharge significantly modified sessile assemblages at I if compared to Cs. We detected significant differences in assemblages at I versus Cs, indicating a clear effect of the effluent on assemblage structure. Such differences were mostly due to shift in dominance among macroalgae between I and Cs, which likely depended on different tolerance limits of species to increased seawater temperature and other sources of disturbance associated to the effluent, such as increased sedimentation rates and water turbidity. Our findings stressed the need for further investigations of the impact of thermal effluents on marine communities, considering the potential synergistic effects of climate change especially in the Mediterranean Sea
Best Practicable Aggregation of Species: a step forward for species surrogacy in environmental assessment and monitoring
The available taxonomic expertise and knowledge of species is still inadequate to cope with the urgent need for cost-effective methods to quantifying community response to natural and anthropogenic drivers of change. So far, the mainstream
approach to overcome these impediments has focused on using higher taxa as surrogates for species. However, the use of such taxonomic surrogates often limits inferences about the causality of community patterns, which in turn is essential for effective environmental management strategies. Here, we propose an alternative approach to species surrogacy, the “Best Practicable
Aggregation of Species” (BestAgg), in which surrogates exulate from fixed taxonomic schemes. The approach uses null models from random aggregations of species to minimizing the number of surrogates without causing significant losses of information on community patterns. Surrogate types are then selected in order to maximize ecological information. We applied the approach to real case studies on natural and human-driven gradients from marine benthic communities.
Outcomes from BestAgg were also compared with those obtained using classic taxonomic surrogates. Results showed that BestAgg surrogates are effective in detecting community changes. In contrast to classic taxonomic surrogates,
BestAgg surrogates allow retaining significantly higher information on species-level community patterns than what is expected to occur by chance and a potential time saving during sample processing up to 25% higher. Our findings showed that BestAgg surrogates from a pilot study could be used successfully
in similar environmental investigations in the same area, or for subsequent long-term monitoring programs. BestAgg is virtually applicable to any environmental context, allowing exploiting multiple surrogacy schemes beyond stagnant perspectives strictly relying on taxonomic relatedness among species. This
prerogative is crucial to extend the concept of species surrogacy to ecological traits of species, thus leading to ecologically meaningful surrogates that, while cost effective in reflecting community patterns, may also contribute to unveil underlying processes. A specific R code for BestAgg is provided
Protection enhances community and habitat stability: Evidence from a Mediterranean marine protected area
Rare evidences support that Marine Protected Areas (MPAs) enhance the stability of marine habitats and assemblages. Based on nine years of observation (2001–2009) inside and outside a well managed MPA, we assessed the potential of conservation and management actions to modify patterns of spatial and/or temporal variability of Posidonia oceanica meadows, the lower midlittoral and the shallow infralittoral rock assemblages. Significant differences in both temporal variations and spatial patterns were observed between protected and unprotected locations. A lower temporal variability in the protected vs. unprotected assemblages was found in the shallow infralittoral, demonstrating that, at least at local scale, protection can enhance community stability. Macrobenthos with long-lived and relatively slow-growing invertebrates and structurally complex algal forms were homogeneously distributed in space and went through little fluctuations in time. In contrast, a mosaic of disturbed patches featured unprotected locations, with small-scale shifts from macroalgal stands to barrens, and harsh temporal variations between the two states. Opposite patterns of spatial and temporal variability were found for the midlittoral assemblages. Despite an overall clear pattern of seagrass regression through time, protected meadows showed a significantly higher shoot density than unprotected ones, suggesting a higher resistance to local human activities. Our results support the assumption that the exclusion/management of human activities within MPAs enhance the stability of the structural components of protected marine systems, reverting or arresting threat-induced trajectories of change
Intra-Laboratory Calibration Exercise for Quantification of Microplastic Particles in Fine-Grained Sediment Samples: Special Focus on the Influence of User Experience
An intra-laboratory calibration to quantify microplastic in fine-grained marine sediments was performed with two objectives: (a) to determine the recovery rate of self-produced microplastics characterized by a size ranging from 220 µm to 5 mm and differing in color (pink, orange, gray, yellow, silver), shape (fragments, filaments, spheres, films), and chemical composition (polystyrene, polyethylene, polyvinyl chloride, acrylonitrile-butadiene-styrene, polypropylene, poly(methyl methacrylate)) artificially introduced into real samples; and (b) to analyze whether operator experience can be a key factor in the quality of the results. To answer this question, the same protocol was assigned to an experienced and an inexperienced operator. The results of this comparison are detailed in terms of root mean square and percent error. Possible strategies to increase the recovery rate are presented, and an ad hoc category, namely “glitter”, was created to adjust the results with respect to this unique type of microplastic usually ignored and excluded from the analysi
The Challenge of Planning Conservation Strategies in Threatened Seascapes: Understanding the Role of Fine Scale Assessments of Community Response to Cumulative Human Pressures
Assessing the distribution and intensity of human threats to biodiversity is a prerequisite for effective spatial planning, harmonizing conservation purposes with sustainable development. In the Mediterranean Sea, the management of Marine Protected Areas (MPAs) is rarely based on explicit consideration of the distribution of multiple stressors, with direct assessment of their effects on ecosystems. This gap limits the effectiveness of protection and is conducive to conflicts among stakeholders. Here, a fine scale assessment of the potential effects of different combinations of stressors (both land- and marine-based) on vulnerable rocky habitats (i.e. lower midlittoral and shallow infralittoral) along 40 km of coast in the western Mediterranean (Ionian Sea) has been carried out. The study area is a paradigmatic example of socio-ecological interactions, where several human uses and conservation measures collide. Significant differences in the structure of assemblages according to different combinations of threats were observed, indicating distinct responses of marine habitats to different sets of human pressures. A more complex three-dimensional structure, higher taxon richness and \u3b2-diversity characterized assemblages subject to low versus high levels of human pressure, consistently across habitats. In addition, the main drivers of change were: closeness to the harbour, water quality, and the relative extension of beaches. Our findings suggest that, although efforts to assess cumulative impacts at large scale may help in individuating priority areas for conservation purposes, the fact that such evaluations are often based on expert opinions and not on actual studies limits their ability to represent real environmental conditions at local scale. Systematic evaluations of local scale effects of anthropogenic drivers of change on biological communities should complement broad scale management strategies to achieve effective sustainability of human exploitation of marine resources
Microbe-assisted seedling crop improvement by a seaweed extract to address fucalean forest restoration
In the Mediterranean, Cystoseira sensu lato (s.l.) (Phaeophyceae) forests have
sharply declined and restoration measures are needed to compensate for the
loss. Assisted regeneration through the outplanting of seedlings grown ex-situ
has proven to be a sustainable option. Optimizing mesocosm culture can
maximize survival of the most critical embryonic stages and reduce long-term
maintenance costs. Host-microbiome interactions could also play a crucial role
in seedling development and welfare. In this context, we aimed to advance a
cultivation protocol that stimulates the growth and fitness of Ericaria amentacea
(Phaeophyceae) seedlings and identify the associated microbial biofilm
communities. Seedlings were cultured in 6 treatments [i.e., filtered seawater
(SW, C, Control), von Stoch-enriched SW (VS), VS + algal extract (VSA), algal
extract-enriched SW: A1< A2< A3]. After the field, A2 seedlings had the highest
cover (1372 ± 53.66 mm2), which was 1.8 and 1.9 times greater than in VS and
VSA, respectively. The addition of the algal extract and nutrients significantly
affected the structure and composition of the microbial community that shifted
over time in each culture medium. We identified a treatment-specific microbial
fingerprint. After the mesocosm phase, A2 was characterized by 4 unique taxa:
Postechiella, Winogradskyella, Roseovarius and Arenibacter (Bacteria). Given the
success of A2 seedlings, we propose the probiotic consortia candidates
characterized by the unique treatment-taxa in conjunction with the shared
taxon Psychroserpens (Bacteria, present in A1, A2, VSA, VS) and the reminder
community. Within the holobiont concept, the effect of algal extract or nutrients
on the algae and/or biofilm could have important consequences for tuning the
overall interaction networks. Our study has shown that macroalgal restoration
could benefit from both the use of commercial algal extract and tailored nutrient
enrichment in ex-situ cultures and the identification of probiotic consortia
candidates that promote seedling growth
The Status of Coastal Benthic Ecosystems in the Mediterranean Sea: Evidence From Ecological Indicators
The Mediterranean Sea is subject to multiple human pressures increasingly threatening its unique biodiversity. Spatially explicit information on the ecological status of marine ecosystems is therefore key to an effective maritime spatial planning and management, and to help the achievement of environmental targets. Here, we summarized scientific data on the ecological status of a selection of marine ecosystems based on a set of ecological indicators in more than 700 sites of the Mediterranean Sea. For Posidonia oceanica seagrass beds, rocky intertidal fringe, and coastal soft bottoms, more than 70% of investigated sites exhibited good to high ecological conditions. In contrast, about two-thirds of sites for subtidal rocky reefs were classified to be in moderate to bad conditions, stressing the need for prioritizing conservation initiatives on these productive and diverse environments. Very little quantitative information was available for the southern Mediterranean Sea, thus monitoring programs and assessments in this area are essential for a representative assessment of the health of marine coastal ecosystems in the whole basin. This overview represents a first step to implement a baseline that, through georeferenced data on ecological status, could help identifying information gaps, directing future research priorities, and supporting improvements to spatial models of expected cumulative impacts on marine ecosystems
Geographic distance, water circulation and environmental conditions shape the biodiversity of Mediterranean rocky coasts
11 páginas, 2 tablas, 3 figuras.Ecological connectivity is important for effective
marine planning and biodiversity conservation.
Our aim was to identify factors important in influencing
variation in benthic community structure on shallow
rocky reefs in 2 regions of the Mediterranean Sea with
contrasting oceanographic regimes. We assessed beta
(β) diversity at 146 sites in the littoral and shallow sublittoral
from the Adriatic/Ionian Seas (eastern region)
and Ligurian/Tyrrhenian Seas (western region) using a
null modelling approach to account for variation in species
richness. The distance decay relationship between
species turnover within each region and geographic
distance by sea was determined using generalised linear
models. Mantel tests were used to examine correlations
between β diversity and connectivity by ocean
currents, estimated from Lagrangian dispersal simulations.
Variation in β diversity between sites was partitioned
according to environmental and spatial components
using a distance-based redundancy approach.
Species turnover along a gradient of geographic distance
was greater by a factor of 3 to 5 in the western
region than the eastern region, suggesting lower connectivity
between sites. β diversity was correlated with
connectivity by ocean currents at both depths in the
eastern region but not in the western region. The influOPEN
ACCESS
ence of spatial and environmental predictors of β diversity
varied considerably between regions, but was similar
between depths. Our results highlight the interaction
of oceanographic, spatial and environmental processes
influencing benthic marine β diversity. Persistent currents
in the eastern region may be responsible for lower
observed β diversity compared to the western region,
where patterns of water circulation are more variable.This work was supported by the
European Community’s 7th Framework Programme (FP7/
2007−2013) under Grant Agreement No. 287844 for the project
‘Towards COast to COast NETworks of marine protected
areas (from the shore to the high and deep sea), coupled
with sea-based wind energy potential (CoCoNet)’.Peer reviewe
The Status of Coastal Benthic Ecosystems in the Mediterranean Sea: Evidence From Ecological Indicators
The Mediterranean Sea is subject to multiple human pressures increasingly threatening its unique biodiversity. Spatially explicit information on the ecological status of marine ecosystems is therefore key to an effective maritime spatial planning and management, and to help the achievement of environmental targets. Here, we summarized scientific data on the ecological status of a selection of marine ecosystems based on a set of ecological indicators in more than 700 sites of the Mediterranean Sea. For Posidonia oceanica seagrass beds, rocky intertidal fringe, and coastal soft bottoms, more than 70% of investigated sites exhibited good to high ecological conditions. In contrast, about two-thirds of sites for subtidal rocky reefs were classified to be in moderate to bad conditions, stressing the need for prioritizing conservation initiatives on these productive and diverse environments. Very little quantitative information was available
for the southern Mediterranean Sea, thus monitoring programs and assessments in
this area are essential for a representative assessment of the health of marine coastal
ecosystems in the whole basin. This overview represents a first step to implement a
baseline that, through georeferenced data on ecological status, could help identifying
information gaps, directing future research priorities, and supporting improvements to
spatial models of expected cumulative impacts on marine ecosystems
An integrated assessment of the Good Environmental Status of Mediterranean Marine Protected Areas
Este artículo contiene 11 páginas, 2 figuras, 2 tablas.Local, regional and global targets have been set to halt marine biodiversity loss. Europe has set its own policy
targets to achieve Good Environmental Status (GES) of marine ecosystems by implementing the Marine Strategy
Framework Directive (MSFD) across member states. We combined an extensive dataset across five Mediterranean
ecoregions including 26 Marine Protected Areas (MPAs), their reference unprotected areas, and a no-trawl case
study. Our aim was to assess if MPAs reach GES, if their effects are local or can be detected at ecoregion level or
up to a Mediterranean scale, and which are the ecosystem components driving GES achievement. This was
undertaken by using the analytical tool NEAT (Nested Environmental status Assessment Tool), which allows an
integrated assessment of the status of marine systems. We adopted an ecosystem approach by integrating data from several ecosystem components: the seagrass Posidonia oceanica, macroalgae, sea urchins and fish. Thresholds to define the GES were set by dedicated workshops and literature review.
In the Western Mediterranean, most MPAs are in good/high status, with P. oceanica and fish driving this result
within MPAs. However, GES is achieved only at a local level, and the Mediterranean Sea, as a whole, results in a
moderate environmental status. Macroalgal forests are overall in bad condition, confirming their status at risk.
The results are significantly affected by the assumption that discrete observations over small spatial scales are
representative of the total extension investigated. This calls for large-scale, dedicated assessments to realistically
detect environmental status changes under different conditions.
Understanding MPAs effectiveness in reaching GES is crucial to assess their role as sentinel observatories of
marine systems. MPAs and trawling bans can locally contribute to the attainment of GES and to the fulfillment of
the MSFD objectives. Building confidence in setting thresholds between GES and non-GES, investing in long-term
monitoring, increasing the spatial extent of sampling areas, rethinking and broadening the scope of complementary tools of protection (e.g., Natura 2000 Sites), are indicated as solutions to ameliorate the status of the
basin.This article was undertaken within the COST Action 15121 MarCons
(http://www.marcons-cost.eu, European Cooperation in Science and
Technology), the Interreg MED AMAre Plus (Ref: 8022) and the project
PO FEAMP 2014-2020 Innovazione, sviluppo e sostenibilita ` nel settore
della pesca e dell’acquacoltura per la Regione Campania (ISSPA 2.51).
M.C.U., A.B. have been funded by the project MEDREGION (European
Commission DG ENV/MSFD, 2018 call, Grant Agreement 110661/
2018/794286/SUB/ENV.C2). Aegean Sea data were retrieved from the
project PROTOMEDEA (www.protomedea.eu), funded by DG for Marine
Affairs and Fisheries of the EC, under Grant Agreement SI2.721917. JB
acknowledges support from the Spanish Ministry of Science and Innovation (Juan de la Cierva fellowship FJC 2018-035566-I).With the institutional support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S).Peer reviewe
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