Download Maritime ENGLISH Session 1 – Part 2 Coastal Habitats Sussex UK

Maritime ENGLISH
Session 1 – Part 2
Coastal Habitats
Sussex UK
Coastal Saltmarsh
Coastal Saltmarsh
Coastal saltmarshes lie at the top of the
intertidal zone on fine sediments. The
vegetation here is adapted to regular
immersion by the tide.
Importance
•Saltmarshes are an important resource for
breeding and wintering wading birds and wildfowl.
•They provide sheltered nursery sites for several
species of fish.
•Areas with high structural and plant diversity are
particularly important for invertebrates.
Threats
•“Coastal squeeze” resulting from coastal development,
erosion and coastal defences, restricts the ability of
saltmarsh habitat to move.
•Disruption of natural coastal processes as a result of
coastal protection work, dredging or coastal defences can
affect natural sediment systems.
•Non-native species such as Cord Grass.
Coastal Sand Dunes
Coastal Sand Dunes
Coastal sand dunes form above the high water
mark on sufficiently large beach plains and are
stabilised by dune-building.
Importance
•Sand dunes display a clear succession of vegetation from Marram Grass
dominance to diverse plant communities, containing rare and specialised
species such as Childing Pink.
•They are important areas for reptiles including the uncommon Sand
Lizard.
•Sand dune systems are important for invertebrates such as bees, moths
and grasshoppers and several notable species can be found.
•Dune systems are important geomorphological structures; existing only
under certain conditions, and they offer a valuable opportunity to study
natural coastal processes.
Threats
•Sand dunes are a mobile habitat however coastal development and sea
defences can restrict their ability to move, threatening their integrity.
•Recreation can damage fragile communities by trampling and erosion of
the dunes.
•A lack of management can result in dominance by scrub and loss of many
important species.
•Introduction of non-native species.
Coastal Vegetated Shingle
Coastal Vegetated Shingle
Shingle is an accumulation of pebbles with a
diameter between 2-200mm. In Sussex the
shingle is composed mainly of flint pebbles
derived by marine or glacial erosion of
Cretaceous chalk and Tertiary deposits.
Importance
•Vegetated shingle is a rare habitat and some of the plants and
animals found here are very restricted in their distribution.
•Nutrient levels are low and many plants found here have special
adaptations to conserve water and prevent damage by salt spray,
wind and shifting shingle.
•Shingle is important for breeding birds, in particular gulls and terns.
•Many rare species are found including species of moth and spider.
Threats
•Coastal defence work can interrupt natural sediment
movement which affects coastal habitats including
vegetated shingle.
•Sea level rise and increased storms could destroy
vegetated shingle areas.
•Recreation impacts including trampling, disturbance of
animals and introduction of non-native plant species.
Intertidal Mudflats
Intertidal Mudflats
Mudflats are sedimentary intertidal habitats
created by deposition in low energy coastal
environments particularly estuaries and other
sheltered areas.
Importance
•Mudflats are part of a habitat sequence between open water and saltmarsh, and
have an important role in reducing the impact of waves upon saltmarshes, damage
to coastal defences and flooding of low-lying.
•A wide range of invertebrates is supported including molluscs, annelids and
lugworms.
•Mudflats are highly productive, making them important feeding areas for birds.
They support internationally important populations of migrant and wintering
waders.
•Due to their sheltered nature mudflats are important areas for fish, in particular
flatfish, which use them as nursery areas.
Threats
•Sea level rise is expected to result in the loss of up to 10000 hectares of
intertidal mudflat by 2013, with much of this in southern England.
•Land claim for development, and industry including hard flood defences.
•Pollution from agricultural, industrial and urban sources.
•Human disturbance from fishing and bait digging can have adverse
impacts.
•Introduction of invasive species such as Cord Grass.
Maritime Cliff and Slope
Maritime Cliff and Slope
Maritime cliffs and slopes comprise sloping to
vertical faces on the coastline where a break in
slope is formed by slippage and/or coastal
erosion. The cliff-top is the area receiving a
maritime influence from salt spray, which may
continue for up to 500 metres
Importance
•Cliff faces provide important nesting sites for birds such as Rock Pipit and
Kittiwake
•The terrestrial and maritime influences have led to evolution of specialist
invertebrates many of which are now scarce; in Sussex this includes species
of beetle, fly and spider.
•A number of rare plants are found on cliff tops including Hoary Stock and
Early Gentian.
•Cliff bases can have important assemblages of lichens and algae.
Threats
•“Coastal squeeze” resulting from coastal development restricting the ability of
coastal habitats to retreat landwards with natural erosion, and fragmenting the
habitat.
•Disruption of natural coastal processes caused by coastal defence work or offshore
dredging can affect natural sediment systems and may actually increase erosion.
•Recreation can cause disturbance to animals and speed up cliff top erosion.
•Lack of management on cliff tops can result in loss of grassland to scrub.
•Increased run-off from arable land or urban areas can accelerate erosion as well as
introducing pollution to the cliff and marine environment.
Saline Lagoons
Saline Lagoons
Lagoons are natural or artificial bodies of
saline water partially separated from the sea
by shingle, sand, a rocky shore or sea wall.
Seawater input can be through percolation, via
a channel or by overtopping.
Importance
•The salinity of lagoons can vary considerably, and they
support specialised species of plants and animals, which
reflect the degree of salinity.
•Lagoons often have soft sediments (mud or sand) making
them important for burrowing invertebrates, and
stoneworts some of which are extremely rare.
•Lagoons provide important habitat for birds.
Threats
•Saline lagoons will often naturally fill-in through vegetation succession. This would
naturally be offset by lagoon creation; however this may be limited by human
activity.
•Pollution, particularly through nutrient enrichment, affects the vegetation
community.
•Artificial control of water input to lagoons will affect salinity.
•Coastal defence work can interrupt natural sediment movement which affects
coastal habitats and structures including lagoons.
•Sea level rise will lead to the loss of some lagoons; however it may also result in
the creation of new ones.