Islands

Insular habitats

The islands in the Atlantic Ocean (extended through the Atlantic and Macaronesian biogeographical regions) have been identified as one of the areas with the greatest biodiversity in the European continent, thanks to the combination of climatic conditions, edaphic and coastal dynamics, for which they are home to a very high diversity of habitat types and species included in DC 92/43/CEE and 2009/147/CE, many of which are considered priorities for conservation. These island ecosystems generally present common environmental problems, which are currently being aggravated by global change (EPA 2017), which means that they are extremely threatened and, consequently, the habitats present in them.

The eminently coastal nature of the spaces in which LIFE INSULAR will act, motivates that the most numerous groups of habitats are the types of coastal habitats and halophytic vegetation together with the habitats of the group of maritime and continental dunes. In turn, in some of the LIFE INSULAR spaces, the bushes acquire great territorial importance. Finally, the spaces house different types of habitats included in the habitat groups of grasslands, rocky environments and forests, with a scarcer territorial representation.

 

 

The internal limit of the coastal zone corresponds to the coastal space, a margin that constitutes the interface between the maritime and terrestrial environments, in which the ecological processes and the uses of each of them directly affect the other. Functionally it is considered as a wide and irregular ecotony with a great intensity in the processes of synthesis, degradation and exchange of matter and energy.

This coastal space is subject to a vigorous and continuous dynamic both in its configuration and in its delimitation. In relation to this coastal dynamic, two units are established: a rocky coast, with a clear dominance of vertical shapes and in contrast to this, we find sandy coasts and tidal flats. The dominant energetic processes in these environments condition the types of habitats and biotic communities present in them.

From an ecological perspective, between the marine and terrestrial ecosystems, a succession of environments and types of habitats is established that present a great diversity and environmental complexity.

Within the group of habitats "Coastal habitats and halophytic vegetation", Annex I of Directive 92/43/EEC establishes six subgroups: 11. Marine waters and tidal media, 12. Maritime cliffs and pebble-bank beaches, 13. Marshes and Atlantic and continental saline grasslands, 14. Mediterranean and thermo-Atlantic salt marshes and grasslands, 15. Continental halophytic and gypsophilous steppes and 16. Archipelagos, coasts and emerged surfaces of the Baltic boreal. The first four groups are represented in the archipelagos in which LIFE INSULAR operates, representing a total of 19 types of habitats, among which one is a priority (1150* Coastal Lagoons).

The great extension of the European coastline and its exposure to the prevailing westerly winds, favour the formation of dune complexes with highly variable morphology and extension. In recent times, the processes of elimination or serious environmental modification of these media have intensified to the point that a large part of them have disappeared, or present a high degree of alteration, mainly in the areas of greatest tourist attraction. This phenomenon is common to the island spaces included in the LIFE INSULAR project.

Aware of all this problem, Annex I of Directive 92/43/EEC includes a specific section dedicated to coastal and inland dune complexes. Within the LIFE INSULAR spaces, there is a wide representation of hard coastal habitats, the most numerous and territorially representative being included in the group 21 Maritime dunes of the Atlantic, North Sea and Baltic coasts, with great homogeneity in terms of to the presence of this group of habitats, except in the Irish locations where habitat 2170 Dunes with Salix repens spp. argentea (Salicion arenariae), absent in the remaining areas of the project. Among the group of dune habitats present in the selected spaces, we find two priority habitats: 2130* Fixed coastal dunes with herbaceous vegetation (grey dunes) and habitat 2150* Calluno Ulicetea fixed decalcified dunes, habitat 1130* being one of the target habitats of the LIFE INSULAR project.

Dune ecosystems of type 2130* make contact, following a horizontal axis, with cliff habitats of type 1230 on the islands of the Atlantic Region and 1250 in the Macaronesian Region. While vertically catenally, they contact different types of coastal scrub, which in turn are also in contact with cliff habitats. Among the groups of scrub habitats, the broad representation of habitat 4030 stands out, another of the habitats targeted by the project.

Among the groups of cliff and scrub habitats, important representations of rocky habitats are included, including siliceous rocks of type 8230, caves not exploited by tourism (8310) or submerged or partially submerged sea caves (8330).

In the LIFE INSULAR spaces as a whole, therefore, the variety, contact and continuity established between the different groups of marine and coastal habitats is remarkable, than in the SACs as a whole. These spaces house representations of a large part of the types identified in the European Atlantic and Macaronesian Bioxeographic Regions, playing an important role from the point of view of biodiversity conservation and natural heritage, given that these ecosystems are highly fragile and vulnerability to the threats identified in the LIFE INSULAR project.

Among the most threatened island habitats are dune ecosystems (2,130*) and their contact habitats (4,030), which is why LIFE INSULAR will implement specific conservation actions in eight SAC Natura 2000 on five islands in the Atlantic Ocean distributed among the regions Atlantic and Macaronesian biogeographical areas, mitigating the 4 main threats identified for habitats 2130* and 4030.

The most up-to-date and precise information on the presence and area occupied by types 2130* and 4030 in the Natura 2000 areas of LIFE INSULAR comes from their respective Standard Data Forms (SDF). The information regarding its state of conservation and main pressures and threats, have been consulted in the latest available evaluation report under article 17 of DC 92/43/CEE, corresponding to the period 2013-2018.

 

 

Habitat 2130* Fixed coastal dunes with herbaceous vegetation (grey dunes)

Priority type 2130* is a representative habitat at the level of presence and surface distribution in all the Natura 2000 areas of LIFE INSULAR, both in those included in the Atlantic biogeographical region and in the Macaronesian one, since it is present in all their respective SDF and occupies significant surfaces in them. All the ZECs of LIFE INSULAR will receive specific conservation actions on 2130*, which occupies a total of 1,163.1 ha within the ZECs of the project, which represents 3.5% of its total territorial area, just over 35,400 ha, although within the insular areas (Cíes, Ons, Sálvora, La Graciosa, Eire) chosen in the ZEC of LIFE INSULAR, habitat 2130* occupies 703.5 ha, which represents 6.8% of the territories islands in the ZEC .

The conservation status of priority habitat type 2130* for the Atlantic biogeographic region is unfavorable-bad according to its area of ​​occupation, structure, functionality and future prospects for it. This negative trend has also been detected in Spain and Ireland (member states involved in LIFE INSULAR), as well as in a general way in the rest of the member states of the Atlantic region, and specifically in the archipelagos object of the project, being aggravated by the insular nature of the territories in question, given the influence that the effects of global climate change have on them, so that the project implements a transnational strategy of sustainable management to mitigate and correct the negative effects, and prevent the spread of some of the threats detected to other ZECs. Among the main threats identified in the Spanish and Irish Atlantic biogeographical region, LIFE INSULAR will act on reforestation, the presence of IAS, the effects caused by anthropogenic pressures, and the effects of global climate change that enhance the above.

The conservation status of the priority habitat type 2130* is considered unfavorable-inadequate in the Macaronesian biogeographical region, although in the evaluation of the Spanish state (referring to the Canary Islands archipelago) the national data considers that the conservation status of 2130* is favorable, since it is estimated that all the parameters that define it are maintained. Despite this positive assessment, several studies have revealed a series of pressures and threats (IAS, anthropogenic pressures) that cause a significant effect specifically on type 2130* in La Graciosa, and therefore justify the need to act to improve its state of conservation, and therefore the implementation of LIFE INSULAR measures.

The impact of the project will be very relevant, since it acts urgently in the island territories where it is necessary to help mitigate or stop the effects of the pressures detected on the priority habitat 2130*, and on the other hand, serving as a method of early action in the face of a series of negative impacts that cannot be recorded in the SDF.

For all of the above, priority habitat 2130* constitutes the main type of habitat targeted by LIFE INSULAR, since this project proposes specific conservation actions on type 2130* to improve its conservation status in a total of 152.6 ha (discounting areas of overlap) on islands in the Atlantic Ocean that are located in 8 SAC Natura, distributed in the regions Atlantic and Macaronesian biogeographical In this way, the project proposes:

- Increase of 32 ha in the area occupied by type 2130*, which represents an increase of 5.2% in the island territories of the ZEC where these actions are carried out.

- Improvement of the future prospects of 133.6 ha of habitat 2130* in all the island territories of the project, through actions that implement measures against anthropogenic pressures, which represents an improvement of 19.0% of the habitat 2130* in the group of islands of the project.

 

 

Habitat 4030 European dry heaths

Type 4030 is a habitat of community interest that constitutes contact with 2130* in the Atlantic island Natura 2000 areas of Galicia (Spain). Within LIFE INSULAR, this habitat will be the object of conservation actions in two SACs where it occupies an area of ​​499.8 ha, that is, 4.9%, although within the island areas of both SACs (Cíes, Sálvora) the area occupied by the 4030 is 275.2 ha, which represents 42.3% of them. The current conservation status of habitat type 4030 for the Atlantic biogeographical region is unfavourable-bad according to structure, functions and future perspectives, a negative trend also detected in the Spanish Atlantic region, and generalized to the rest of the Atlantic Member States. Among its main threats are reforestation, the presence of IAS and the effects caused by anthropogenic pressures, all of them with a medium degree. The negative trend caused by these pressures and threats have been identified in the archipelagos object of the project, being aggravated by the insular nature of the territories in question, taking into account the influence that the effects of global climate change have on the same, so that the project implements a comprehensive sustainable management strategy to mitigate and correct the negative effects, and prevent the expansion of some of them to other SACs. The impact of the project will be very relevant, since it acts urgently in the island territories where it is necessary to help mitigate or stop the effects of the pressures detected on type 4030, and on the other hand, serving as a method of early action in the event of a series of negative impacts that cannot be recorded in the SDF. Due to the above, LIFE INSULAR proposes specific conservation actions on the 4030 habitat to mitigate the main effects of the threats and pressures detected, with a view to improving its conservation status in a total of 117.0 ha in the archipelagos of Cies and Salvora. In this way, the project proposes:

- Increase of 22 ha (11.6%) in the area occupied by type 4030 in the Cíes Islands.

- Improvement of the structure and functionality of 95 ha of habitat 4030, which represents an improvement of 34.5%.

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