Seagrass meadows in Pontic moderately exposed upper infralittoral clean sands
.jpg "D. Micu, S.Beal,V.V.Alexandrov, E.B.Chernysheva, D.Korolesova, V. Mihneva,N. A. Milchakova, B. Yokes")
.jpg "D. Micu, S.Beal,V.V.Alexandrov, E.B.Chernysheva, D.Korolesova, V. Mihneva,N. A. Milchakova, B. Yokes")
Quick facts
| Red List habitat type | code BLSA5.5z |
|---|---|
| Threat status | |
| Europe | Data Deficient |
| EU | Data Deficient |
| Relation to |
|
| Source | European Red List habitat factsheet |
| European Red List of habitats reports | |
| European Red List of habitats (Excel table) |
Summary
The habitat occurs in the upper infralittoral zone, on clean sands at depths between 0.2 to 3m. It is characterized by sedimentary stability and a low silt content of 5-10%. The dominant seagrass species is Zostera noltei, which may form monospecific or mixed meadows (with Zostera marina, Ruppia spp. and Zannichellia pedicellata). Of areas surveyed in detail, the maximum biomass and density of this seagrass in the Black Sea has been measured in the Karkinitsky Bight, where it occurs on sandy substrate mixed with silt. Other species of seagrass are also present in this habitat and 62 macroalgal species. Algae with short life cycles, mostly red algae, dominate, with epiphytic and unattached forms usually prevailing over epilithic forms.
Indicators of quality:
Leaf length, biomass, shoot density have all been identified has indicators of quality. In Romania the following thresholds have been defined: Low fragmentation of habitat; cover of Z. noltei inside the meadow ≥50%; leaf length in June ≥70 cm; annual outward growth of rhizomes from the meadow ≥70 cm; above-ground biomass of Z. noltei in June ≥1,600 g/m2.
Threat status
Synthesis of Red List assessment
| EU | |
| Red List Category | Red List Criteria |
| Data Deficient | - |
| Europe | |
| Red List Category | Red List Criteria |
| Data Deficient | - |
Confidence in the assessment
Pressures and threats
- Urbanisation, residential and commercial development
- Other urbanisation, industrial and similar activities
- Biological resource use other than agriculture & forestry
- Professional active fishing
- Human intrusions and disturbances
- Outdoor sports and leisure activities, recreational activities
- Motorised vehicles
- Other human intrusions and disturbances
- Trampling, overuse
- Pollution
- Nutrient enrichment (N, P, organic matter)
Habitat restoration potential
Trends in extent |
|
Average current trend in quantity |
|
Increasing  |
Increasing |
| EU28 | EU28+ |
Trends in quality |
|
Average current trend in quality |
|
Decreasing  |
Stable  |
| EU28 | EU28+ |
Conservation and management needs
Conservation and management measures which would benefit this habitat include implementing measures to maintain physical and biological integrity, including pollution control and regulation; improvement of water quality management outside EU member states; coastal development controls; contingency plans to be followed in the event of a major pollution incident; survey and monitoring programmes; raised public awareness of ecological value and vulnerability; enhanced legal protection for occurrences of the habitat and key species (e.g. additions to the EU Habitats Directive, establish a unified list of Black Sea species and habitats requiring conservation measures, etc.); and the designation of MPAs.
List of conservation and management needs
- Measures related to marine habitats
- Other marine-related measures
- Restoring marine habitats
- Measures related to spatial planning
- Establish protected areas/sites
- Legal protection of habitats and species
- Measures related to hunting, taking and fishing and species management
- Regulation/Management of fishery in marine and brackish systems
Distribution
Geographic occurrence and trends
| Seas | Present or presence uncertain | Current area of habitat (Km2) | Recent trend in quantity (last 50 years) | Recent trend in quality (last 50 years) |
|---|---|---|---|---|
| Black Sea | Present | Unknown | Stable | Decreasing |
| Sea of Marmara |
Extent of Occurrence, Area of Occupancy and habitat area
| Extent of Occurrence (EOO) (Km2) | Area of Occupancy (AOO) | Current estimated Total Area | Comment | |
|---|---|---|---|---|
| EU28 | Unknown | Unknown | Unknown | The habitat is known to occur in the Black Sea but there is insufficient data to accurately calculate EOO and AOO. |
| EU28+ | Unknown | Unknown | The habitat is known to occur in the Black Sea but there is insufficient data to accurately calculate EOO and AOO. |
EOO = the area (km2) of the envelope around all occurrences of a habitat (calculated by a minimum convex polygon).
