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This is Gibraltar Point National Nature Reserve on the northwest corner of the Wash in Lincolnshire.
It's incredible to think that this entire landscape has formed as result of deposition in just a few hundred years.
Gibraltar Point lies at the southern end of a sediment cell that stretches from here all the way to Flamborough Head, 116 kilometres to the north.
A sediment cell is a stretch of coastline in which sediment can move around, but sediment rarely enters or leaves the area of that cell.
Much of the Lincolnshire coastline has receded by between 400 and 800 metres over the last 500 years.
The Holderness Coast, to the north of Gibraltar Point, is the fastest receding coastline in all of Europe.
Much of the sediment that's eroded up at the Holderness Coast is transported south by longshore drift, and it's deposited right here, where the orientation of the coastline changes, creating the sheltered environment of Gibraltar Point.
All this deposition has created a five square kilometre area of land, comprising of a well-developed ridge and runnel foreshore, sand dunes, and salt marshes.
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Twice a day the tide moves across this beach, by up to 7 meters on the highest spring tides.
At low water, you can see exposed a very large beach, a wide beach, and also, offshore, some large sandbanks.
The wide beach that we can see here, and the offshore banks, show us just how much sediment deposition is taking place here at Gibraltar Point.
This beach is a very important source of sediment for dune development.
The sand is picked up by the wind, and bounced across the beach surface by a process known as saltation.
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That sediment that's been carried up the beach by saltation starts to get deposited around here, just above the high-water mark, and this is where sand dune development begins.
In the first stage of sand dune formation, the wind comes into contact with an obstacle, like this driftwood, a rock, a shell, or even some litter.
The wind slows down, deposits its sand, and it starts to build up against these obstacles.
This spiky little plant is Prickly Saltwort, and it's a pioneer species on this sand dune, which is helping to build up and stabilise the sand in which it's growing.
Most plants would die in this environment but the Prickly Saltwort, with the help of its waxy leaves and deep roots, are able to get the nutrients that it needs out of this sandy soil and saltwater environment.
The Prickly Saltwort is helping to stabilise the sand on the sand dune here, and also it acts as a shield that slows down more wind, causing more sand to be deposited, and the sand dune to grow.
These small, delicate sand dunes are called embryo dunes.
They are right next to the beach, and they're the youngest sand dunes that we get along this coastline.
These embryo dunes here have probably formed in the last few months or so.
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Just inland from the embryo dune is this foredune, where sand is really starting to accumulate.
We have these salt-tolerant vegetation species, like Sand Couch Grass, and Lyme Grass, and they're really starting to take hold.
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Just beyond the foredune, this first main ridge of dunes are called yellow dunes.
These yellow dunes have been here for 30 or 40 years, so they're really well-established in terms of vegetation.
Marram Grass is really common on yellow dunes, and this stuff is really good at stabilising the dune and trapping sand.
These dunes are called yellow dunes because of the sand that they're made of, which gives them a yellow colour.
But as we start to go inland, this all starts to change.
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Further from the coast the dunes are more protected from the inundation of seawater, and so we start to see more and more vegetation.
And what's more, that vegetation is changing.
Whereas before we had a lot of salt-tolerant species like Marram Grass, here it's not as salty, and so more species are able to grow, like this Sea Buckthorn, and perennial species like Dewberry, which we have here.
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We call these grey dunes, and you can see why when you look at the colour of the soil.
This is a sample of sand that we collected from the yellow dune, which is much closer to shore, and you can see just how yellow that is, in comparison to this sample, which we've collected from the grey dune.
You can see that in this grey dune there's much more organic matter and humus, and if you compare the two samples side by side, you can really see the contrast in colour between the yellow dune and the grey dune.
Mosses and lichens like these, which are growing on the surface of the dune, also help to give the dunes their grey colour.
Embryo dunes, foredunes, and yellow dunes are all known as mobile dunes, because they can be disturbed or even destroyed by severe storms.
But these grey dunes here are much more fixed and permanent.
They're in a well-sheltered location and they're far away from the influence of the sea.
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The oldest sand dunes here are found over a kilometre inland, far from the influence of the sea where the sand dune system reaches its climax.
The environment here is completely changed: we've got heath covered in shrubs with more Sea Buckthorn and Hawthorn, and we've got deciduous woodland here with mature trees such as Oak, Maple, and Ash.
The ground here is different as well.
There's a lot more organic matter and humus contained in the soil, and it's also very moist, and that's because the water table here is very close to the surface.
The dunes here at the climax are over 250 years old, dating back to the mid 18th century.
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Today, we can see the succession of vegetation, from pioneer plants all the way up to climax species, creating a changing environment as we travel through these sand dunes.
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The landscape here at Gibraltar Point is an incredible place to visit, to see the processes of a depositional coastal landscape at work.
However, this environment is very sensitive to disturbances.
The area is designated a Ramsar wetland site, which means it is carefully managed to preserve the landscape and ecosystems.
School groups wishing to visit the area can do so by contacting the National Nature Reserve Office using the contact details shown below this video.
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