|Protection and Management of Coastal Habitats in Latvia|
Monitoring Methods and Results
In years 2003 ā€“ 2006, sites of actions C1 ā€“ C6, C8, D1, E10, E12 ā€“ E21 were monitored. In every site, coordinates were recorded, photos taken. Habitats were described, their area and level of human influence evaluated. Permanent sample plots for the description of vegetation were established. Size of sample plots was 4x4 metres in open dunes and grasslands. In forests, plots of size 10x10 metres (tree stand) and 1x1 metres (ground floor vegetation) were established. Along boardwalks, 1x2 m plots were established.
In permanent sample plots, vegetation was described. The description of vegetation was based on floristic derived from methodology of Braun ā€“ Blanquet. According to this method, all the plant species in the sample plot are being registered, and their projective cover (%) is being evaluated (Coker, Kent 1992). This is the most common used method of vegetation description and therefore it gives a possibility to compare data with other vegetation descriptions done by other botanists in whole world.
Plots in following habitats of Community importance were set: grey dunes, 2130* (147 sample plots), wooded dunes, 2180 (94 ā€�largeā€¯ and 371 ā€�smallā€¯ plots), coastal grasslands, 1630* (303), foredunes, 2110 and 2120 (491).
Managed sites in Saulkrasti, Roja, Rucava, JÅ«rmala were monitored 3 times ā€“ in summer before the management and in 2 following summers. Sites where the building of small-scale infrastructure was finished in year 2005 (RÄ«ga, LapmeÅ¾ciems, PÄ�vilosta, SalacgrÄ«va, UÅ¾ava, Carnikava,) or in 2006 (Medze, AinaÅ¾i), were monitored only 2 times ā€“ before and after the management.
For the classification of vegetation data, analysis of dichitomical ordination TWINSPAN provides by program PC-Ord was used (McCune, Mefford 1999).
Boreal Baltic coastal meadows is very rare habitat in Latvia, and most of it is included in Natura 2000 sites. According to habitat mapping (Action A2), this habitat covers 130.9 hectares of the project area. Coastal grasslands of Randu PÄ¼avas Nature Reserve and PiejÅ«ra Nature Park belong to the most diverse and species-rich grasslands of whole Latvia. Main threat to these grasslands is the ceasing of management (grazing, mowing). Abandoned grasslands gradually overgrow with reed, shrubs and trees. In grasslands close to RÄ«ga, grasslands are threatened also by the expansion of invasive shrub species (Amelanchier spicata, Rosa rugosa).
Coastal grasslands were managed in RÄ«ga (VakarbuÄ¼Ä¼i and DaugavgrÄ«va Nature Reserve) and in SalacgrÄ«va (Randu pÄ¼avas Nature Reserve), since year 2003. Vegetation was recorded since year 2003. In all sites, the aim of management has been achieved - the representativity of habitat of Community importance has increased because:
- the abundance of indicatorspecies of seminatural grasslands (including rare and in Latvia protected plant species, for example Armeria maritima, Gladiolus imbricatus, Triglochin maritimum, Dactylorhiza incarnata, D. maculata, and other orchids) has increased.
- the abundance of indicators of overgrowing (Phragmites australis, Filipendula ulmaria, Lythrum salicaria, Salix sp.) has decreased;
- the abundance of Angelica palustris (species of Community importance, also very rare species in Latvia) has increased in mown areas (it appeared also in sites where it was not found before the management).
The success of restoration of grasslands depends on the management method, intensity and time since abandonment.
Mowing. In all sites, the trend is positive ā€“ the biodiversity is increasing in managed sites. In VakarbuÄ¼Ä¼i, the time since abandonment is lesser than in SalacgrÄ«va, therefore it was easier to reach an optimal situation. In SalacgrÄ«va, the vegetation composition is still changing, number of species is growing.
Grazing. In all sites, the trend is positive. As typically for grazing management, the intensity of grazing differs in various sites of the fencing, and the species composition becomes more mosaic. Area close to shelter is grazed and also trampled more intensively, remote areas are less influenced.
In SalacgrÄ«va, compared with previous years, the intensively grazed area is increased, the abundance of reeds decreased. In RÄ«ga, grazing was started only in this year. However, there is already a positive trend. In grazed wet areas, the abundance of Trifolium fragiferum is increasing. In dryer areas, diverse grassland with Nardus stricta, Sieglingia decumbens, Helictotrichon sp. is recovering.
Shrubs were cut in VakarbuÄ¼Ä¼i Nature Reserve (2003 and 2005).
The management can be considered as successful. Vitality, height and density of shrubs has been decreased. The abundance of typical species of these habitats has increased. After repeated cutting, rare grassland species started to grow in sites which were previously dominated by Rosa rugosa or Amelanchier spicata. Remaining shrubs now are low, and grasslands can be managed by mowing which was not possible earlier.
2.2. EMBRYONIC SHIFTING DUNES, 2110, AND WHITE DUNES (SHIFTING DUNES ALONG THE SHORELINE WITH AMMOPHILA ARENARIA), 2120.
Embryonic shifting dunes are formations representing the first stages of dune construction, constituted by raised sand surfaces of the upper beach or by a seaward fringe at the foot of the tall dunes. White dunes are mobile dunes forming the seaward cordon or cordons of dune formation. Vegetation exists in a very dynamic state. Embryonic dunes and white dunes together are called primary dunes.
According to habitat mapping in year 2003, embryonic dunes cover 147.2 hectares and white dunes cover 727.9 hectares of the project area. Embryonic and white dunes are threatened mainly by activities of visitors ā€“ trampling, driving, leaving wastes etc.
The word ā€�strengtheningā€¯ is used not in sense to stop natural process but in sense of strengthening of dunes against man-made deterioration (mainly, against the trampling). Dunes were strengthened only in sites with high anthrophogenic pressure, in short patches.
White dunes were strengthened in Saulkrasti, AinaÅ¾i and LapmeÅ¾ciems. Dunes were strengthened with woven branches which is the traditional way of dune strengthening in these areas.
Management can be considered as successful. In all sites, strengthenings were not damaged by the storm of January 2005. Between the branches, the vegetation is recovering ā€“ Ammophila arenaria, Festuca arenaria, Cakile baltica, Viola tricolor and other.
In Southern parts of SalacgrÄ«va and AinaÅ¾i, open dunes were overgrown with dense Salix viminale, S. daphnoides, Pragmites australis stands. Overgrowing occurred as the result of management of harbour (lack of sand). Shrubs were cut and the area was repeatedly ploughed.
1-2 years after the management we can consider this measures as successful. The structure, dynamics and vegetation of embryonic dunes have been recovered. Typical species are: Honckenya peploides, Cakile baltica. In areas close to grey dunes Carex arenaria is spreading. It is expected that the management effect will be more pronounced after few years.
2.2.4. Establishment of small-scale infrastructure for visitors, actions E10, E12, E13, E14, E15, E16, E17, E19, E20.
The aim of the establishment of small-scale infrastructure was to decrease the trampling in dunes. Boardwalks were established in very heavily used sites with large areas of bare sand.
The management can be considered as successful. People use the boardwalks. Vegetation is recovering up to the sides of boardwalks where typical foredune species grow now ā€“ Ammophila arenaria, Leymus arenarius, Festuca arenaria. The area of bare, trampled sand has decreased.
Grey dunes are fixed dunes, stabilised and colonised by more or less closed perennial vegetation - grasses, sedges, lichens, and moss. Grey dunes cover 1256.2 hectares of the Latvian coast.
Grey dunes are threatened by activities of visitors (trampling etc.), by inappropriate management (mainly by building), and in some sites also by expansion of invasive species.
Latvian grey dunes are very valuable in European context because grey dunes of Western Europe are threatened by eutrophication which is not the case of Latvia.
In grey dunes, following restoration and management actions were realised: cutting of invasive shrub species and establishment of small-scale infrastructure for visitors.
Area of 120 hectares in western coast of Latvia (LiepÄ�ja district) was restored by cutting of rugose rose Rosa rugosa. Cutting was repeated.
The management can be considered as successful. In all sites, the abundance, vitality, density and height of Rosa rugosa was decreased in the next year after the management. Cover of typical grey dune plant species Carex arenaria, Calamagrostis epigeios increased.
However, the re-growth of shoots can be observed. To stop the dispersal of Rosa rugosa in grey dunes, the continuation of cutting and application of other, more effective methods is necessary.
In sites with high visitor pressure, the network of boardwalks of various types, car parking sites and resting sites was established. Boardwalks were built mainly in highly visited areas, where the dunes are being destroyed due to trampling.
The management can be considered as successful. The majority of people use the boardwalks. In all sites the vegetation structure typical for grey dunes is recovering. Few trampled and slightly eroded sites remain as the optimal disturbance which ensure the necessary sandblow.
Bare sand is firstly occupied by Carex arenaria and Festuca sabulosa. Grey dune vegetation is recovering up to the sides of boardwalks where mosses and herbs can be found now.
For example, in DaugavgrÄ«va (action E10), the total cover of vegetation has been increased by 30%, during 1 year after the management.
2.4. Wooded dunes of the Atlantic, Continental and Boreal region, 2180; Boreal forests (Western taiga), 9010*.
Wooded dunes are natural or semi-natural forests on coastal dunes. In Latvia, dune woodlands typically are dominated by Scots pine (Pinus sylvestris). This habitat is widely distributed along the Latvian coast (14298.3 hectares of the project area) but is rare in the European context.
If the forest on dunes is old, naturally developed, rich with structures which are important for biodiversity (old trees, coarse woody debris etc.), it corresponds for the priority protected habitat Boreal forest. This habitat covers 678.7 hectares of the project area.
Wooded dunes are threatened mainly by visitor activities (driving, trampling, wastes etc.), inappropriate management (building; removal of old trees and woody debris; sand digging).
Dunes were strengthened in RagakÄ�pa Nature Park. It was realised in sites where dune structure is being deteriorated because of trampling, close to small-scale infrastructure established by the project. Dunes were strengthened with woven branches which is the traditional way of dune strengthening in this area.
Management can be considered as successful. People use the boardwalks; the erosion has been stopped. Strengthenings have overgrown with typical vegetation of pine forests ā€“ moss Pleurosium schreberi, herbs Lerchenfeldia flexuosa, Melampyrum pratense and others.
In dune forest in RagakÄ�pa Nature Park, alien shrub species Amelanchier spicata, Cotoneaster lucidus, Rosa rugosa, R. subcanina, Eleagnus commutatus were cut.
The aim of the management was reached ā€“ the vitality, density and height of alien species is decreased. It was very important to restore the forest microclimate. For example, the illumination of pine stems is necessary for the conservation of rare insect species Nothorhina punctata.
2.4.4. Establishment of small-scale infrastructure for visitors, actions E12, E14, E16, E17, E18, E21.
To protect the structure and vegetation of dune forests and to rise the public awareness, networks of boardwalks, observation sites, resting sites was established.
Management can be considered as successful. People use boardwalks, and the number of visitors is increasing. Vegetation is recovering up to the sides of boardwalks. Previously degraded sites are being occupied by typical forest species ā€“ moss Pleurosium schreberi, Hylocomium splendens, Brachithecium albicans, herbs Lerchenfeldia flexuosa, Melampyrum pratense. With the establishment of boardwalks, the habitats of rare species further from boardwalks are preserved ā€“ Pulsatilla pratensis, Peucedanum oerselinum, Dianthus arenarius, Geranium sanguineum. Close to boardwalks growing Linnaea borealis and Geranium sanguineum are indicating on the healthy forest understorey.
It is observed that the recovery of vegetation is more slow in the most dry and sunny sites (like the very old dune forest in Saulkrasti) than in more shaded sites. However, similar positive trend has been observed in all sites.
Several coastal habitats of Community importance are threatened by invasive species - white, grey and wooded dunes, coastal grasslands and others. As this is a newly understood problem in Latvia, a study of the distribution of invasive species was necessary before the management (Actions C1, C2, C4, C8).
In year 2002, the distribution of invasive species was studied in large part of Latvian coast.
In LiepÄ�ja District, 40 kilometres of the coast were studied and sample plots were set (192 plots with Rosa rugosa, 9 belts with Asparagus officinalis, 18 belts with Gypsophyla paniculata, 568 plots for control ā€“ with typical dune vegetation). In RÄ«ga District (Saulkrasti - Skulte) and in JÅ«rmala (RagakÄ�pa Nature Park) 88 sites with invasive species were described, 10 large and 49 small sample plots were set.
It was found that the most common invasive species are shrubs Rosa rugosa and Amelanchier spicata, in SW part of Latvia also herbs Asparagus officinalis and Gypsophyla paniculata, in some sites also Lactuca tatarica.
The most aggressive species is Rosa rugosa which expands both in open dunes and also in dune woodlands and grasslands. It is widely distributed in the western coast of Latvia (between Priediengalciems and Nida). Here it is randomly distributed, building dense stands which expand, and species is also spreading by fruits and root sprouts carried by the sea.
In foredunes, several stands of Eleagnus commutata were found. However, Eleagnus is not concluded as an invasive species because it has been planted here and is not spreading by seeds.
In RagakÄ�pa and RÄ«ga district, the most threatened habitat is wooded dunes where Amelanchier spicata is the most common invasive species. Often, it grows together with alien species Cotoneaster lucidus and also with Lonicera xylosteum, Sorbus aucuparia and Ribes alpinum which are local species but common in more fertile habitats. In dune woodlands, these species mostly are distributed in vicinity to settlements where their distribution is supported by soil eutrophication.
Of dune woodlands, the oldest forests (which are sparse and light) are the most threatened by Amelanchier spicata which build dense stands here. Rosa rugosa spreads only in the vicinity to the sea (in 5 - 25 m wide belt).
As the control of invasive species is a very topical subject in Latvia now, whole report on this study with annexes is published here on the project website:
http://piekraste.daba.lv/LV/peetiijumi/sveso_sugu_izplatiiba/. In annexes, there are maps and coordinates of the studied sites. TWINSPAN tables of the studied sample plots are published in Annex 27.
Results are being used by Latvian Agency of Latvian Environment, Geology and Meteorology and Ministry of Agriculture (State Plant Protection Service).
National monitoring program. Monitoring is partly continued in scope of Biodiversity monitoring in Latvia, section ā€�Coastal habitat monitoringā€¯ (coordinated by Agency of Latvian Environment, Geology and Meteorology, in accordance to national program of biodiversity monitoring). In total, 5 monitoring stations are described each year, and two of our project monitoring sites (PÄ�vilosta, action E15 and DaugavgrÄ«va, actions C2, D1 and E10) were included in 2006. In 2007, it is planned to continue use also other our monitoring sited.
Research. Coastal monitoring aspects are insufficiently studied both in Latvia and in other countries. Therefore in the Faculty of Biology, a new research project on the evaluation of coastal habitats was started in year 2006. Possible bioindicators of condition disturbances of coastal habitats are ā€“ species composition of plant communities, plant projective cover. Aim of the study is to find indicators which could be used by local people and pupils and so the long-term monitoring could be ensured and local public involved.
Habitat map elaborated by our LIFE project is the background of further evaluation of changes of habitat area (such maps were not available earlier). Mapping should be repeated after every 5 years.
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Protection and Management of Coastal Habitats in Latvia