Montane grasslands and heaths

Context

Montane grasslands and heaths include a range of vegetation types that occur exclusively in mountains, such as prostrate dwarf shrub heath, snow-bed communities, sedge and rush heaths, and moss heaths. The distinction between the sub-montane and montane zone is often blurred and the two usually merge through a band of transitional vegetation.

Exclusively montane habitat types can be recognised by their floristic composition and character (prostrate vegetation). Widespread arctic-alpine species such as stiff sedge Carex bigelowii, crowberry Empetrum nigrum hermaphroditum, trailing azalea Loiseleuria procumbens, dwarf willow Salix herbacea, and alpine clubmoss Diphasium alpinum, in association with woolly fringe-moss Racomitrium lanuginosum or cladonia lichens Cladonia spp., and other macro-lichens such as Cetraria islandica, are indicators of montane communities. Montane calcareous grasslands are enriched by a distinctive assemblage of arctic-alpine plants, such as alpine lady's mantle Alchemilla alpina, moss campion Silene acaulis, spring gentian Gentiana verna and mountain avens Dryas octopetala.

Calcareous grasslands, fens and springs, blanket bog and rock habitats which also occur in the montane zone are included in this habitat type rather than in the Calcareous grassland, Fens and marshes, Bog, and Limestone pavement, inland cliffs and scree reporting categories.

SSSIs can be notified if they qualify under criteria outlined in Chapter 9 Upland habitats of the Guidelines for Selection of Biological SSSIs. In Northern Ireland, ASSIs are selected on a very similar basis – the Guidelines for the Selection of Biological ASSIs in Northern Ireland is an addendum to the SSSI guidelines rather than an alternative.

Summary statistics

	SAC	A/SSSI	Total
Favourable condition	27%	45%	32%
Main monitoring coverage	E, S	E, S
Reported assessments	49	20	69
Completeness of assessments	53%	unknown
Distribution of features			UK

Number of assessments reported by country and site type

Country	SAC	SSSI/ASSI
England	5	7
Scotland	41	11
Wales	1	0
Northern Ireland	2	2
United Kingdom	49	20

Natura features

List of Natura 2000 interest features within this reporting category

Interest feature name
Formal name	Informal name	No. of assessments reported	Total no. of features	% assessed
Alpine and Boreal heaths	Alpine and subalpine heaths	15	33	45%
Alpine and subalpine calcareous grasslands	Alpine and subalpine calcareous grasslands	9	15	60%
Siliceous alpine and boreal grasslands	Montane acid grasslands	17	29	59%
Sub-Arctic Salix spp. scrub	Mountain willow scrub	8	15	53%

Natura 2000 comprises Special Protection Areas (under the Birds Directive) and Special Areas for Conservation (under the Habitats and Species Directive). The list presented here includes all of the qualifying interest features under these Directives, and shows the proportion of these features for which a condition assessment has been made.

SSSI features

List of SSSI and ASSI interest features in this reporting category

Interest feature name
Formal name	Informal name	No. of assessments reported
Alpine and Boreal heaths	Montane heath	1
Alpine calcareous grassland	Alpine calcareous grassland	2
Alpine heath	Alpine heath	7
Alpine moss heath and associated vegetation	Alpine moss heath and associated vegetation	1
Montane assemblage	Montane assemblage	1
Montane habitats	Montane habitats	7
Siliceous alpine and boreal grasslands	Montane heath	1

This list has not been fully standardised at a UK level yet. It is intended to show the principal constituent "feature types" for this reporting category.

Maps - distribution

UK distibution of reported interest features

Distribution of reported interest features.

Map showing the locations of the 10km squares in which at least one condition assessment has been reported. It does not show features that have not yet been assessed.

Maps - Natura

Current condition of SAC features
Distribution of SAC features showing assessments of favourability (where unfavourable-recovering is counted as unfavourable).

Condition of SAC features, with those currently reported as unfavourable-recovering shown as favourable
The implication of the unfavourable-recovering condition assessments is that at some point in the future these features should become favourable. This map shows the effect of that recovery by counting the favourable and unfavourable-recovering assessments together.

IMPORTANT NOTE: we do not have information on the timescale of the predicted recovery, which may be influenced by many past, natural and human related factors. A sustained sympathetic management regime is more likely to result in favourable condition being attained.

Key: Proportion of assessed features on 10km squares that are favourable:

Natura map legend - Key: proportion of assessed features on 10km squares that are favourable

Details of how these maps were produced

Maps - SSSI

Current condition of SSSI/ASSI features
Distribution of SSSI/ASSI features showing assessments of favourability (where unfavourable-recovering is counted as unfavourable).

Condition of SSSI/ASSI features, with those currently reported as unfavourable-recovering shown as favourable
The implication of the unfavourable-recovering condition assessments is that at some point in the future these features should become favourable. This map shows the effect of that recovery by counting the favourable and unfavourable-recovering assessments together.

Key: Proportion of assessed features on 10km squares that are favourable:

SSSI map legend - Proportion of assessed features on 10km squares that are favourable

Details of how these maps were produced

Condition summary

This lists the 10 different condition assessments and presents a bar chart showing the number of features within the SSSI series and the Natura 2000 series (either SPA for bird features or SAC for features other than birds). Note that for Natura 2000 we are able to estimate the number of features that have not been assessed during the 6 year reporting period - we are unable to do this for SSSI/ASSI because we do not have an overall list of notified interest features for these designations.

NB favourable unclassified and unfavourable unclassified have been used in this first six year cycle to get around difficulties in identifying trends in condition as common standards monitoring is implemented. It is expected that these categories will not be used for subsequent assessments of a feature.

Condition assessment - Natura 2000 features

The number and proportion of assessments for Natura 2000 (SAC and SPA) interest features falling into each of the condition categories. Note that the �unfavourable� category includes all reports of unfavourable condition except �unfavourable recovering� which is shown as a separate segment.

Condition assessment - SSSI features

The number and proportion of assessments for SSSI/ASSI interest features falling into each of the condition categories. Note that the �unfavourable� category includes all reports of unfavourable condition except �unfavourable recovering� which is shown as a separate segment.

Adverse activities

The number of interest features where an activity has been reported as being implicated in the "unfavourable" condition of a feature. More than one adverse activity may be reported for each feature.

Management measures

For each "measure" the chart shows the number of interest features where that measure has been taken on a site to improve or maintain the condition of an interest feature. More than one measure may be reported for each feature assessed.

Interpretation

32% of alpine grass and heath features reported are in favourable condition. This is below the average for terrestrial habitats, all habitats or all features combined. 45% of the A/SSSI features and 27% of SAC features reported are in favourable condition. 10% of A/SSSI and 12% of SAC features reported are unfavourable-recovering.

The reported activity that has had the greatest impact contributing to unfavourable condition on montane features is over-grazing. This leads to loss of vegetation structure and the failure of more palatable or vulnerable species to reproduce and maintain themselves. It can also lead to the loss of plant species and associated fauna, and the spread of rank, unpalatable plant species. In extreme cases, very heavy grazing and trampling can lead to exposure of bare soil and erosion. There is, therefore, a need for grazing to be undertaken at the right time and with the right intensity. Recent research indicates that air pollution in the form of nitrogen deposition and ozone, may have significant impacts on montane vegetation. At the present time, however, it is not possible to determine what the detail of the impacts are, or what interaction any such impacts might be having with the grazing pressure.

The reporting of measures taken to address unfavourable condition indicates that management agreements/schemes and agri-environment schemes are in place on many sites. However, it is not yet known how long it may take to return montane features to favourable condition.