Seagrass ecosystems status between the sliding baseline syndrome and the need for reference conditions

Marine coastal ecosystems are facing compositional and functional changes due to the increasing human footprint worldwide, and the assessment of their long-term changes becomes particularly challenging in this new "Anthropocene Epoch". Measures of change can be done by comparing the present ecosystem status to a defined baseline representing the reference condition. The "syndrome" of the sliding (or shifting) baselines, which describes the incremental lowering of ecological standards, has become a major concern when long-term changes have to be assessed because an already degraded environment status could be accepted as reference. The challenge of delineating ecosystems change in the context of sliding baselines is particularly relevant along highly anthropized coasts, as the case of the Liguria (NW Mediterranean Sea), where pristine coastal areas could not be expected anymore. The Marine Strategy Framework Directive (MSFD, 2008/56/EEC) suggests three approaches to define reference conditions: i) comparison with the status in Marine Protected Areas (MPAs); ii) use of historical information; iii) modelling. Here we report recent applications of these three approaches in Liguria to assess the status of seagrass meadow ecosystem. Ligurian MPAs are too recent and often insufficiently enforced, so that Posidonia oceanica meadows developing in MPAs are far from the expected good ecological status. Available historical information on seagrass distribution was sometime unreliable. Models are promising but face intellectual difficulties (e.g., choice of descriptors). Validating historical data with predictive models showed effective in delineating the trajectory of change experienced by the Ligurian seagrass meadows. Many meadows have been lost and most are showing structural degradation, which favoured the substitution by alien green algae of the genus Caulerpa and triggered a phase shift in the seagrass ecosystems, with the consequent loss of biodiversity, functioning and economic value of the ecosystem services provided by healthy meadows.

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Seagrass ecosystems status between the sliding baseline syndrome and the need for reference conditions

10.7287/peerj.preprints.1018 ◽

2015 ◽

Author(s):

Monica Montefalcone ◽

Matteo Vacchi ◽

Carla Morri ◽

Marco Ferrari ◽

Carlo Nike Bianchi

Keyword(s):

Reference Conditions ◽

Ecological Status ◽

Posidonia Oceanica ◽

Historical Information ◽

Functional Changes ◽

Seagrass Meadows ◽

Long Term Changes ◽

The Status ◽

Seagrass Ecosystems

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An environmental database for the status of freshwater in Greece

Global NEST Journal ◽

10.30955/gnj.000229 ◽

2013 ◽

Vol 4 (1) ◽

pp. 1-14

Keyword(s):

National Level ◽

Reference Conditions ◽

Ecological Status ◽

Anthropogenic Pressures ◽

Environmental Pressures ◽

Physico Chemical ◽

Other Information ◽

The Status ◽

Freshwater Bodies ◽

Status Data

An environmental database has been created, recording water bodies at a national level and assembling relevant data collected by various public services and institutions in charge of water resources management and research in Greece. Data consists of physico-chemical parameters, geomorphological descriptions, inventories of fauna and flora species, environmental pressures, vulnerability evaluation and other information useful for the assessment of current and future ecological status. Data gathering has proven to be a challenging task, due to the large number and the generally small size of the surface freshwater bodies as well as the numerous competent services and institutions and the multiple and sometimes conflicting responsibilities that therefore result. The latter is also partly the cause of lack of continuity of data, gaps or sometimes questionable reliability. Performing a global data overview, we note that (a) ecological status can be characterized as good for the majority of the sites, especially for small mountain streams, and (b) the general trend in most cases is degradation of current conditions, related either to anthropogenic pressures or to human activity combined with natural factors. This database, in a more completed and enriched form, could assist in the implementation of 2000/60/EC Directive in Greece and the establishment of reference conditions of surface freshwater systems.

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Long-term changes in water quality and ecological status of lakes in the Wielkopolska National Park and its buffer zone with special reference to effectiveness of the lakes’ protection

Oceanological and Hydrobiological Studies ◽

10.1515/ohs-2016-0044 ◽

2016 ◽

Vol 45 (4) ◽

Cited By ~ 1

Author(s):

Agnieszka E. Ławniczak

Keyword(s):

Water Quality ◽

Catchment Area ◽

National Park ◽

Ecological Status ◽

Buffer Zone ◽

Field Studies ◽

Long Term Changes ◽

Protection Strategies

AbstractThis paper evaluates water quality and ecological status of lakes located in the Wielkopolska National Park and its buffer zone. Changes in water quality were analyzed from 1974 to 2012 in order to assess the effectiveness of the protection strategies implemented on the studied lakes since 1957, i.e. the date when the park was established. The ecological status of the lakes was assessed with the use of macrophytes as well as hydromorphological and physicochemical analyses performed in 2012. Changes in water quality of the studied lakes within the last 40 years were analyzed based on available published and unpublished data, as well as field studies. All water bodies are characterized by advanced eutrophication. However, evaluation of the ecological status showed good status of the charophyte-dominated lakes, i.e. Lake Wielkowiejskie and Lake Budzyńskie. Lack of significant differences in physicochemical water qualities between the park and its buffer zone indicated that measures implemented to protect the water, particularly in the park, are ineffective. This study shows that more radical conservation measures are necessary to protect and improve the water quality, not only in WPN and its buffer zone but also in the whole catchment area.

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Recent monitoring data of Posidonia oceanica meadows distributed along the Apulian coasts (Eastern-Central Mediterranean Sea) according to the 2000/60 EC Directive

10.7287/peerj.preprints.1068 ◽

2015 ◽

Author(s):

Gaetano Costantino ◽

Nicola Ungaro ◽

Massimo Blonda ◽

Marina Mariani ◽

Daniela Battista ◽

...

Keyword(s):

Adriatic Sea ◽

National Level ◽

Reference Conditions ◽

Ecological Status ◽

Posidonia Oceanica ◽

Ionian Sea ◽

Ecological Data ◽

Central Mediterranean ◽

Italian Law ◽

Sampling Procedures

According to the Water Framework Directive (WFD), a specific monitoring of Posidonia oceanica meadows was carried out along the Apulian coasts by the Regional Agency for the Environmental Prevention and Protection (ARPA Puglia). A total of 17 sites, 11 in the Southern Adriatic Sea and 6 in the Northern Ionian Sea were investigated during two consecutive monitoring cycles (2009-2011 and 2012-2014). Sampling procedures as well as laboratory analyses (phenology and lepidochronology) were carried out according to a common methodological protocol shared at Italian national level (D.M. 260/2010) for the final ecological classification (sensu WFD) using the PREI index. In each meadow, two sampling stations were investigated by scuba divers at the fixed depth of 15 m and in correspondence of the lower bathymetric distribution limit. For each station, 9 shoots counting (40x40 cm square) and 3 covering estimates (around 5 m of radius) were carried out. In addition, 18 orthotropic shoots and a sediment sample were collected as well as some other bio-ecological data (meadow continuity, dead matte presence, bottom type, invasive algae presence, flowering, disturbance sources, lower limit type and depth). The results showed that 29% of sites were classified as “GOOD”, 59% were classified as ”MODERATE” while the remaining 12% as “POOR”, with a general slight improvement of the classification in the last monitoring cycle (2012-2014). Although the ecological quality status of the Apulian Posidonia oceanica meadows (summarized by the PREI index values) reflects the distribution of anthropic pressures on the coast (harbours, industrial and urbanized areas, river’s outlets) along a latitudinal gradient, the classification based on the rules (reference conditions and EQR boundaries for the PREI index) reported in the Italian law (D.M. 260/2010) seems to underestimate the real ecological status. Consequently, a revision of both the actual reference conditions and EQR boundaries is suggested for the BQE Posidonia oceanica in the Apulian marine waters, in order to taking account of the environmental features of two different marine basins as the south-western Adriatic Sea and the north-western Ionian Sea.

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Depauperate seed banks in urban tropical seagrass meadows

Marine and Freshwater Research ◽

10.1071/mf19204 ◽

2020 ◽

Vol 71 (8) ◽

pp. 935

Author(s):

Glendon Hong Ming Ong ◽

Samantha Lai ◽

Siti Maryam Yaakub ◽

Peter Todd

Keyword(s):

Seed Bank ◽

Large Scale ◽

Seed Viability ◽

Seed Banks ◽

Dormant Seed ◽

Seagrass Meadows ◽

Halophila Ovalis ◽

The Status ◽

Cymodocea Rotundata

Seagrasses need to be resilient if they are to persist in the long term. Being able to build up a dormant seed bank in sediments is a key strategy that some species employ to regenerate from large-scale degradation. Much of the research on seed banks has focussed on temperate species, and little is known regarding the status of seed banks in tropical meadows. In the present study, we examined the seed bank status of three common seagrass species at six sites in Singapore and attempted to identify potential drivers of seed abundance. Our results indicated depauperate seed banks with few species setting viable seed and low seed densities. Halophila ovalis seeds were found at four sites and Halodule uninervis seeds at two sites, but Cymodocea rotundata seeds were absent from all six sites. Whereas H. ovalis seed viability ranged from 20% to 68.8%, none of the H. uninervis seeds was viable. Halophila ovalis seed densities (33–334m–2) were much higher than those of H. uninervis (9–21m–2). Of the variables examined, only H. ovalis cover was positively correlated with the number of seeds. Our study has highlighted the vulnerability of seagrass meadows in Singapore’s urban waters to future disturbances.

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Ecological status of seagrass ecosystems: An uncertainty analysis of the meadow classification based on the Posidonia oceanica multivariate index (POMI)

Marine Pollution Bulletin ◽

10.1016/j.marpolbul.2011.06.016 ◽

2011 ◽

Vol 62 (8) ◽

pp. 1616-1621 ◽

Cited By ~ 17

Author(s):

Scott Bennett ◽

Guillem Roca ◽

Javier Romero ◽

Teresa Alcoverro

Keyword(s):

Uncertainty Analysis ◽

Ecological Status ◽

Posidonia Oceanica ◽

Seagrass Ecosystems

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Restoration of Seagrass Meadows in the Mediterranean Sea: A Critical Review of Effectiveness and Ethical Issues

Water ◽

10.3390/w13081034 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1034

Author(s):

Charles-François Boudouresque ◽

Aurélie Blanfuné ◽

Gérard Pergent ◽

Thierry Thibaut

Keyword(s):

Ethical Issues ◽

Scientific Paper ◽

Posidonia Oceanica ◽

Natural Ecosystem ◽

Seagrass Meadows ◽

Halophila Stipulacea ◽

The Mediterranean ◽

Term Monitoring ◽

Sea Warming

Some species of seagrasses (e.g., Zostera marina and Posidonia oceanica) have declined in the Mediterranean, at least locally. Others are progressing, helped by sea warming, such as Cymodocea nodosa and the non-native Halophila stipulacea. The decline of one seagrass can favor another seagrass. All in all, the decline of seagrasses could be less extensive and less general than claimed by some authors. Natural recolonization (cuttings and seedlings) has been more rapid and more widespread than was thought in the 20th century; however, it is sometimes insufficient, which justifies transplanting operations. Many techniques have been proposed to restore Mediterranean seagrass meadows. However, setting aside the short-term failure or half-success of experimental operations, long-term monitoring has usually been lacking, suggesting that possible failures were considered not worthy of a scientific paper. Many transplanting operations (e.g., P. oceanica) have been carried out at sites where the species had never previously been present. Replacing the natural ecosystem (e.g., sandy bottoms, sublittoral reefs) with P. oceanica is obviously inappropriate in most cases. This presupposes ignorance of the fact that the diversity of ecosystems is one of the bases of the biodiversity concept. In order to prevent the possibility of seagrass transplanting from being misused as a pretext for further destruction, a guide for the proper conduct of transplanting is proposed.

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Long-term changes in the trophic state of Suwalki lakes – an analysis by means of indices based on abundance and composition of their rotifer fauna

Limnological Review ◽

10.1515/limre-2016-0021 ◽

2016 ◽

Vol 16 (4) ◽

pp. 199-205 ◽

Cited By ~ 1

Author(s):

Jolanta Ejsmont-Karabin ◽

Andrzej Górniak ◽

Elżbieta Jekatierynczuk-Rudczyk ◽

Maciej Karpowicz ◽

Adam Więcko

Keyword(s):

Species Composition ◽

Trophic State ◽

Trophic Factors ◽

Long Term Changes ◽

The Status ◽

Rotifer Communities

Abstract Rotifer abundance and species composition in lakes of the Suwalki Landscape Park were studied in the years 1983–1985, 2009, 2012 and 2015. Rotifer trophic state indices (TSIROT) were used to assess changes in the trophic state of the studied lakes. In most lakes of the Suwalki Landscape Park, there were no changes in rotifer communities over the 25–32 year period to indicate a decline in trophy of the lakes. However, in lakes with the strongest decline in TSIROT values, the values of indicative parameters widely varied in 2015, which may indicate that the status of rotifer communities in the lakes may be dependent on non-trophic factors.

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