Upper Thurne Broads and Marshes
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Norfolk Team 60 Bracondale NORWICH NR1 2BE Tel: +44 (0)1603 598400 Fax: +44 (0)1603 762552 Email: [email protected] cSAC: The Broads SPA: Broadland Component SSSI: Upper Thurne Broads and Marshes Conservation objectives for the European Interest on the SSSI The conservation objectives for the European interest on the SSSI are: to maintain*, in favourable condition, the: Alluvial forests with Alnus glutinosa and Fraxinus excelsior. Calcareous fens with Cladium mariscus and species of the Carex davallianae. Natural eutrophic lakes with Magnopotamion or Hydrocharition-type vegetation. Transition mires and quaking bogs. Hard oligo-mesotrophic waters with benthic vegetation of Chara spp.. Molinia meadows on calcareous, peaty or clayey-silt-laden soils (Molinion caeruleae). to maintain*, in favourable condition, the habitats for the population of: Otter (Lutra lutra). to maintain*, in favourable condition, the habitats for the populations of Annex1 bird species+ of European importance with particular reference to: open water swamp fen reedbed lowland wet grassland with ditches and water bodies. +Bittern, Marsh harrier, Hen harrier, Bewick’s swan, Whooper swan and Ruff. to maintain*, in favourable condition, the habitats for the populations of migratory bird species+ of European importance with particular reference to: open water swamp fen reedbed lowland wet grassland with ditches and water bodies. +Pink-footed goose, Gadwall and Shoveler. to maintain*, in favourable condition, the habitats of the populations of waterfowl that contribute to the wintering waterfowl assemblage of European importance, with particular reference to: open water swamp and fen lowland wet grassland with ditches and water bodies. * maintenance implies restoration if the feature is not currently in favourable condition. The Conservation Objectives for The Broads candidate Special Area of Conservation and Broadland Special Protection Area are, in accordance with para C 10 of PPG 9, the reasons for which the cSAC was designated and the SPA classified. The entry of 30 January 1996 on the Register of European Sites gives the reasons for which the SPA was classified. The Broads cSAC and Broadland SPA includes land within: Alderfen Broad SSSI, Ant Broads and Marshes SSSI, Barnby Broad and Marshes SSSI, Broad Fen, Dilham SSSI, Bure Broads and Marshes SSSI, Burgh Common and Muckfleet Marshes SSSI, Calthorpe Broad SSSI, Cantley Marshes SSSI, Crostwick Marsh SSSI, Decoy Carr, Acle SSSI, Ducan’s Marsh, Claxton SSSI, Geldeston Meadows SSSI, Hall Farm Fen, Hemsby SSSI, Halvergate Marshes SSSI, Hardley Flood SSSI, Limpenhoe Meadows SSSI, Ludham-Potter Heigham Marshes SSSI, Poplar Farm Meadows, Langley SSSI, Priory Meadows, Hickling SSSI, Shallam Dyke Marshes, Thurne SSSI, Smallburgh Fen SSSI, Sprat’s Water and Marshes, Carlton Colville SSSI, Stanley and Alder Carrs, Aldeby SSSI, Upper Thurne Broads and Marshes SSSI, Upton Broads and Marshes SSSI and Yare Broads and Marshes SSSI. The Broads cSAC additionally includes land within: Damgate Marshes, Acle SSSI and Trinity Broads SSSI. Favourable Condition Table for Upper Thurne Broads & Marshes SSSI The Favourable Condition Table will be used by English Nature and other relevant authorities to determine if a site is in favourable condition. Favourable condition is achieved when the targets given below are met. The favourable condition table should inform the scope and nature of any ‘appropriate assessment’ under the Habitats Regulations, but an appropriate assessment will also require consideration of issues specific to the individual plan or project. The favourable condition table does not by itself provide a comprehensive basis on which to assess plans and projects as required under Regulations 20-21, 24, 48-50 and 54 - 85. The scope and content of an appropriate assessment will depend upon the location, size and significance of the proposed project. English Nature will advise on a case by case basis. Following an appropriate assessment, competent authorities are required to ascertain the effect on the integrity of the site. The integrity of the site is defined in para C10 of PPG9 as the coherence of its ecological structure and function, across its whole area, that enables it to sustain the habitat, complex of habitats and/or the levels of populations of the species for which it was classified. The determination of favourable condition is separate from the judgement of effect upon integrity. For example, there may be a time-lag between a plan or project being initiated and a consequent adverse effect upon integrity becoming manifest in the condition assessment. In such cases, a plan or project may have an adverse effect upon integrity even though the site remains in favourable condition. Annual counts for qualifying bird species will be used by English Nature, in the context of five year peak means, together with available information on UK population and distribution trends, to assess whether the SPA is continuing to make an appropriate contribution to the Favourable Conservation Status of the species across Europe. Upper Thurne Broads and Marshes SSSI v2 15/11/00, Page 1 Operational Criteria Attribute Measure Target Comments Feature Feature Alluvial Parts of NVC Extent Extent/location of No loss of ancient semi- * Stand loss due to natural processes e.g. in minimum forests with types W2 and stands natural stands intervention stands may be acceptable. Alnus W5 and 6) * A high proportion of this type of woodland may be glutinosa and At least current area of recent and hence a dynamic interchange with open wet Fraxinus recent semi-natural stands communities may occur. excelsior maintained, although * Stand destruction may occur if the understorey and (Alno-Padion, their location may alter. ground flora are irretrievably damaged even if the canopy Alnion remains intact. incanae, * Loss = 0.5 ha or 0.5% of the stand area, whichever is the Salicion At least the area of smaller. alvae) ancient woodland * 20% canopy cover is conventionally taken as the lower retained limit for an area to be considered as woodland. Stands of willow scrub may pose difficulties of definition. * Area and location of stands may be assessed remotely or by site visit. Upper Thurne Broads and Marshes SSSI v2 15/11/00, Page 2 Operational Criteria Attribute Measure Target Comments Feature Feature Semi-natural 2. Natural Age/size class * At least the current * Any changes leading to exceedance of these limits due woodland processes and variation within and level of structural to natural processes are likely to be acceptable. structural between stands; diversity maintained. development presence of open space and old trees; * Understorey (2-5m) * There is generally a good structural variety in these dead wood lying on present over at least 20% stands although veteran trees may be under-represented the ground; standing of total stand area because of past treatment and the unstable nature of some dead trees sites. * Ground flora present * The ground flora may appear sparse, particularly where over at least 50% of area periodic flooding leaves areas of bare mud etc. Its excluding temporary pool composition may be variable ( see attribute 5). areas * Canopy cover present * In coppiced stands a lower canopy cover (of standards) over 30-90 % of stand can be accepted. area * Age class structure appropriate to the site, its * See JNCC guidance note for the sorts of age structure history and management. likely to be appropriate for different types of management regime. * A minimum of 3 fallen lying trees or major * Dead wood is often abundant but because there tend to branches per ha and 4 be fewer big trees the size of the fallen wood is often trees per ha allowed to small. Flooding may lead to local accumulations with die standing. other areas totally lacking fallen wood. * Assess this attribute by field survey. Structures associated * At least the current with the hydrological level of natural * Where possible the hydrological regime should be regime also need to hydrological features allowed to revert to a more natural state. (channels, pools, be considered. should be maintained periodic flooding) Upper Thurne Broads and Marshes SSSI v2 15/11/00, Page 3 Operational Criteria Attribute Measure Target Comments Feature Feature 3.Regeneration Successful * Signs of seedlings * A proportion of gaps at any one time may develop into potential establishment of growing through to permanent open space; equally some current permanent young stems in gaps saplings to young trees at open space/glades may in time regenerate to closed or on the edge of a sufficient density to canopy. stand maintain canopy density * Regeneration may often occur on the edges of stands over a 10 yr period (or rather then in gaps within it. equivalent regrowth from * In coppice most of the regeneration will be as stump coppice stumps). regrowth. See JNCC Guidance Note on likely desirable levels of regeneration. * No planting in stands. * The minimum level of regeneration to be acceptable from a nature conservation viewpoint is likely to be much less than that needed where wood production is also an objective. * Assess this attribute by walking through the wood in spring/summer. Upper Thurne Broads and Marshes SSSI v2 15/11/00, Page 4 Operational Criteria Attribute Measure Target Comments Feature Feature 4. Composition Cover of native * At least the current * In sites where there might be uncertainty as to what versus non-native level of site-native counts as site-native or as an acceptable naturalised species (all layers) species maintained. species this must be made clear (e.g. the position of poplar). * At least 90% of cover in * Where cover in any one layer is less than 100% then the any one layer of site- 90% target applies to the area actually covered by that native or acceptable layer. naturalised species. * Factors leading to the death or replacement of woodland species could include pollution, including eutrophication Death, destruction or * Death, destruction or from adjacent farmland; new diseases (e.g.