02A2
Littoral sands and muddy sands
Relationships with habitat classifications. EUNIS: A2.2 Littoral sands and muddy sands; PAL. CLASS.: 11.27 Soft sediment littoral communities, 14.1 Mud flats and sand flats; HD 92/43: 1140 Mudflats and sand flats not covered by seawater at low tide.
Conservation status. BDA, BC, HD.
Category. Vulnerable [VU – A1, 2 D2 E2 G1 H1].
General characteristics. In the Black Sea, as a result of the lack of real tidal waves, the habitat includes sands and muddy sands in the surf area called the mediolittoral. The typical sandy mediolittoral is typical for the open coasts, while the muddy sands occur mostly in calm estuaries and can be influenced by fresh waters inflow. Littoral sediments are inhabited by organisms tolerant to certain drought, to varying temperatures and low salinity in the estuaries. In general the plant communities are poorer in species due to the conditions described and the mobility of the sediment in the mediolittoral zone. Coarse and medium-coarse sand grains subjected to strong waves are inhabited by the fast-burrowing mussel (Donacilla cornea) and the polychaete worm (Ophelia bicornis), with maximal registered frequency 9800 individuals m2 and 2000 individuals m2 respectively. Small-grained sands are inhabited by the crustacean Pontogammarus maeoticus. In some sheltered areas the mediolittoral fine-grained sands are inhabited by sea grasses from the genus Zostera.
Characteristic taxa.
- Vascular plants. Zostera marina, Z. noltii.
- Animals. Polychaeta: Ophelia bicornis, Nerine cirratulus, Saccocirrus papillocercus, Pisione remota, Hesionides arenaria;Bivalvia: Donacilla cornea;Crustacea: Eurydice dolfusi, Gastrosaccus sanctus, Pontogammarus maeoticus.
Distribution in Bulgaria. Black Sea, on sedimentary beaches, at 0–1 m depth.
Conservation importance. The following species of national and international conservation value occur in the habitat: Donacilla cornea, Hesionides arenarius, Ophelia bicornis and Zostera marina.
Threats. The habitat is on the border between sea and land, as a result of which it is particularly vulnerable to anthropogenic activities on the land, especially in the coastal area. Main threats are eutrophication, pollution including solid wastes, building of constructions protecting the beach that change the hydrology, grain size of the sediments and beach morphodynamics, tourism development in the coastal area, including death of living organisms caused by trampling.
Conservation measures taken. The habitat in included in Annex 1 of the Bulgarian Biodiversity Act. Some of its localities are in sites of the European Ecological Network NATURA 2000 in Bulgaria.
Conservation measures needed. The protection of this habitat needs its inclusion in a unified network of protected marine sites; elaboration and implementation of management plans; further investigation dedicated to the changes of the areas of distribution and fragmentation of the habitat, observations of the habitat state, composition and structure of the communities; periodical assessment of the conservation status of the typical species for the habitat according to the modern criteria and categories of IUCN.
References. Kiseleva 1981; Konsulov 1998; Marinov 1990; Palazov & Stanchev 2006.
Author: Valentina Todorova
