81 - Greater Thames Estuary : Analysis: Landscape Attributes & Opportunities

Analysis supporting Statements of Environmental Opportunity

The following analysis section focuses on the landscape attributes and opportunities for this NCA.

Further analysis on ecosytem services for this NCA is contained in the Analysis: Ecosytem Services section.

Landscape attributes

Extensive open spaces within a predominantly flat, low-lying landscape give heightened importance to the skyscape and dominating skylines.

Justification for selection:

• Open skylines are a particular characteristic of the low-lying estuary landscape.
• A large and varied bird population adds movement to the expansive skyscape.
• Modern development, including expanding settlements, power stations, mineral extraction works, caravan parks and transport networks, is often highly visible within the open landscape and has had a significant impact upon the area.

Geological exposures of Tertiary and Quaternary deposits in soft eroding cliffs and foreshores and in quarries and pits, plus geomorphological interest of the estuary itself.

Justification for selection:

• A dynamic ‘soft’ coastline continually influenced by the action of waves and tides on the mobile sediments results in the ongoing erosion, accretion and creation of coastal landscapes.
• The area contains two of the 11 Geological Conservation Review Saltmarsh Morphology Sites in Great Britain.
• The coastline of the Isle of Sheppey provides some of the best examples of recent mass movement in Britain.
• Important exposures of Tertiary sedimentary rocks such as at Walton-on-the-Naze, an exposure of London Clay with a rich source of fossils.
• Exposures of Thames gravels with associated archaeological artefacts and paleoenvironmental remains.
• Recreational and educational opportunities provided by important fossil collecting sites.
• Geological SSSI provide important access to geodiversity and opportunities for research and education.

Geological contrast and variety within the Estuary is reflected in low islands such as Sheppey, Foulness, Northey and Mersea.

Justification for selection:

• Sheppey rises from a stretch of very flat marsh along the Swale estuary in Kent, with low, steep, clay cliffs facing north towards Essex.
• Mersea is a low island in the Blackwater Estuary in Essex with sand/gravel cliffs.

Reclaimed grazing marsh and its associated habitats, including sea walls, reedbeds, ditches and saline lagoons, notably in Kent where extensive tracts remain.

Justification for selection:

• Coastal grazing marsh is a freshwater-brackish habitat created from reclaimed areas of salt marsh and supports a wide range of species.
• Sustained by sea defences, much of it now lies as much as a metre below mean sea level.
• Around 64 per cent of grazing marsh has been lost since 1945, most of it to arable conversion.
• The habitat is identified as being at high risk to the direct impacts of climate change (England Biodiversity Strategy – towards adaptation to climate change. Mitchell, R.J et al., 2007, Defra, UK).

Other semi-natural estuarine habitats, including intertidal sand and mudflats, salt marsh, sand dunes, shingle, shell and sand banks, and subtidal sand and mud.

Justification for selection:

• These habitats occur in front of sea defences, supporting a wide variety of wildlife.
• Extensive areas covered by international designation, including Essex Estuaries SAC (over 3,700 ha) and ten SPAs covering nearly 15,000 ha (and extending inshore).
• Intertidal sand and mudflats support a wide range of invertebrates and significant populations of breeding waders and wintering wildfowl.
• The NCA has a larger area of salt marsh than any other area in England, supporting a very specialised flora of species as well as key examples of classic salt marsh morphology.
• Significant threat of habitat loss due to coastal squeeze, with salt marsh identified as being at high risk to the direct impacts of climate change (England Biodiversity Strategy – towards adaptation to climate change. Mitchell, R.J et al., 2007, Defra, UK).

Arable farmland helping to support important populations of breeding birds, notably Brent geese.

Justification for selection:

• The NCA supports over 50,000, or more than a fifth of the world population, of the dark-bellied variety of Brent geese.
• The management of arable field margins and the availability of winter stubbles are crucial to the survival of breeding birds.
• Conflict with Brent geese damaging crops.

Nationally important open mosaic habitat on previously developed brownfield sites supporting assemblages of rare and scarce invertebrates.

Justification for selection:

• Brownfield sites provide an important refuge for rare invertebrate species, including the brown-banded carder bee and shrill carder bee.
• Flower-rich and open sward brownfield habitats have developed on post-industrial sites, particularly in south Essex, the Colchester area and the north Kent coast, including Canvey Wick SSSI.
• These habitats and the species they support are now very scarce in ‘natural’ areas due to the loss of flower-rich grasslands.

Limited woodland cover predominantly associated with farmsteads and villages on higher ground.

Justification for selection:

• Woodland (just 1 per cent of NCA) associated with settlement on higher ground forms distinctive vertical elements in the landscape.

A network of ancient reed-fringed drainage ditches and dykes reflecting historic patterns, including regular medieval field systems associated with villages, irregular medieval or earlier patterns at Sheppey, Cliffe and Foulness, and the extremely ancient grid system of the Dengie peninsula.

Justification for selection:

• Field patterns are frequently extremely ancient in origin, with strong linear systems running tangentially to rivers (for example the grid-like field system of the Dengie peninsula, thought to be over 2,000 years old).
• Regular medieval field systems associated with villages and small settlements are similarly aligned towards the coast and estuaries, with frequent 20th century enlargement (notably around Tilbury, Rochford and Tillingham).
• Medieval or earlier irregular drained fields are characteristic of Sheppey, the Cliffe marshes, Foulness and the Dengie marshes, interspersed with later more regular drained enclosure of the 18th or 19th century.

Rich historic associations include Neolithic and Iron Age features, and most notably a distinctive military heritage along the coastline such as Napoleonic military defences and 20th century pillboxes.

Justification for selection:

• Prominent military associations include the historic naval dockyards surviving at Sheerness and Chatham, the string of Martello towers built in the Napoleonic Wars along Clacton Beach, a number of distinctive forts, and the pillboxes from the Second World War.
• Abundant remains relating to local salt-industries, with iron-age/Roman sites on the Essex Marshes and later medieval salt mounds on the edge of the Kent Marshes.
• Extensive areas of Neolithic land surface in the Blackwater Estuary and rare Neolithic causewayed enclosures at Orsett on the north Thames side and Kingsborough Farm on the Isle of Sheppey.
• Widespread evidence for late bronze-age settlement, extending inland from the coastal marshland and associated with a range of field systems and funerary monuments.
• Iron-age defended enclosures survive as earthworks or as cropmark signatures, such as at Prittlewell Camp, near Southend and Danes Camp, Shoebury.

Settlement pattern of numerous small villages and hamlets located on higher ground reflecting the medieval layout of parishes.

Justification for selection:

• Medieval settlement patterns of numerous small villages and hamlets located on higher ground and on the edge of the marshes.
• Historic settlement patterns related to the coastal economy of fishing and boatbuilding.
• Local vernacular predominantly of red brick and weather boarded houses, nucleated villages around churches, and isolated farmsteads, including a large number of pre-1750s buildings.
• Some of the least settled parts of the English coast.

Strong feelings of remoteness and wilderness persist on the open beaches and salt marshes, the reclaimed farmed marshland and on the mudflats, with 37 per cent of land still classified as ‘undisturbed’ according to CPRE data.

Justification for selection:

• Tranquillity and perceptions of remoteness are important characteristics of the NCA.
• Such large remaining areas of tranquillity are unusual so close to London and thus represent an important resource.

Landscape opportunities

• Protect the open spaces and expansive skylines from intrusive development, conserving the large areas of tranquillity and remoteness that remain especially remote coastal habitats and low lying islands.
• Protect the historic settlement pattern of numerous small villages and hamlets located on higher ground reflecting the medieval layout of parishes, and ensure new development is sympathetic to the built character of these settlements.
• Protect the network of ancient reed-fringed drainage ditches and dykes that include very ancient inland patterns (for example, those of the Dengie peninsula) and regular medieval patterns by the coast,
• Protect exposures of Tertiary and Quaternary deposits in soft eroding cliffs and foreshores, including important sites for London Clay fossils and Thames gravel exposures and enhance the recreational, research and interpretation opportunities provided by internationally important fossil collecting sites.
• Protect the geomorphological processes that shape the estuary, allow natural processes to continue unimpeded, and enhance the opportunities for research, education and interpretation they provide.
• Protect the area’s rich historic and archaeological associations that include Neolithic and iron-age features, and most notably a distinctive military heritage along the coastline such as Napoleonic military defences and 20th-century pillboxes, and improve interpretation and promotion of these assets to reinforce the sense of history of the estuary and connect communities with their local heritage.
• Protect key open mosaic habitats and species on brownfield sites through site protection, mitigation and habitat creation.
• Manage and significantly restore areas of coastal grazing marsh and its associated habitats, including sea walls, reedbeds, ditches and saline lagoons, re-linking fragmented habitats to create a robust wildlife network with enhanced adaptation to climate change.
• Manage estuarine habitats including intertidal sand and mudflats, salt marsh, sand dunes, shingle, shell and sand banks, and subtidal sand and mud, supporting their adaptability to sea-level rise and maintaining opportunities for natural regeneration and allowing natural processes to continue unimpeded where appropriate, and identifying possibilities for creation of compensation habitats in other locations where they will be lost to coastal squeeze.
• Manage and enhance existing arable farmland helping to support important populations of breeding birds, notably dark-bellied Brent geese, including through the creation of arable field margins and conservation headlands.
• Plan to create new landscapes that include sustainably managed broadleaved woodlands that provide a setting to urban areas, as well as existing disused industrial land and mineral/waste sites, to significantly enhance landscape character and help to protect the tranquil and open character of the estuary.