Sand Dunes Flashcards

1
Q

What type of deposition are sand dunes formed by?

A

Aeolian deposition- the entrainment of sediment by surface creep and saltation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are sand dunes officially known as?

A

They are officially known as psammoseres.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What do sand dunes rely on?

A

Fluid Threshold Velocity.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the Fluid Threshold Velocity?

A

This is where the strength of the wind is enough to move sand particles.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the 6 requirements for sand dunes to form?

A
Lots of sediment. 
Lots of wind energy. 
Fine sediment. 
Large tidal range. 
Large back shore.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are xerophytes?

A

These are plants that can survive in areas with little water and sand.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What causes more and more vegetation to grow?

A

Plants die and pass on humus which allows more and more vegetation to grow.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is humus?

A

Nutrients

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are pioneers?

A

These are plants that are able to survive in bare ground.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is plant succession?

A

This is where plants invade and take over until an equilibrium is reached.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What starts plant succession?

A

Pioneer species.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How long does plant succession last for?

A

It may take hundreds of years to complete.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is secondary succession?

A

This is when land has been exposed to human activities before plant succession takes place?

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is faster plant succession or secondary succession?

A

Secondary succession

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What do pioneer species survive on exposed sites without?

A

They survive without competition.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What do pioneer species do to the environment?

A

They modify the environment by forming and binding soil.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What type of plants help the soil to retain moisture?

A

Creeping plants or those with leaf cover.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What allows other species to colonise?

A

The changes to the environment allow other species to develop.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What happens when other species colonise?

A

The pioneer species can no longer compete and therefore die out.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What will happen to the community if there are no limiting factors?

A

The final community will be adjusted to the climatic conditions which is known as the climatic climax community.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is each stage of plant succession known as?

A

Each stage is a seral stage.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Why is it rare that plant succession reaches climatic climax?

A

Soil conditions, relief and drainage characteristics or the human management of the land may stop this.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What are the factors that stop a climatic climax being reached called?

A

Arresting factors.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is developed instead of a climatic climax community?

A

A subclimax community.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What are the embryo dunes at Studland colonised with?
Sea crouch grass Lyme grass Marram grass
26
What is a property of Lyme grass?
It is salt resistant.
27
What is a key property of marram grass?
It can withstand dry weather.
28
What is a problem with marram grass?
It can't survive in salt water.
29
What are the yellow dunes at Studland known as?
Zero Ridge
30
How long has Zero Ridge been around for?
About 50 years.
31
Is Zero Ridge mobile or fixed?
It is mobile.
32
What three plants can be found at Zero Ridge?
Red fescue Sand sedge Marram grass
33
What are the two fixed/ semi fixed dunes at Studland called?
Studland First Ridge and Second Ridge
34
What plants are found at Studland First Ridge?
Dandelions Sea bind weed Heather Moss
35
What else can be found at Studland First Ridge?
Lichen Butterflies Lizards
36
What can be observed at Second Ridge?
Heather Gorse Not much marram grass Thin line of humus
37
What do some parts of the Studland dune slack contain?
Stretches of water
38
What is the largest stretch of water at Studland called?
The Little Sea
39
What can be found at the Studland dune slack?
Small trees Water loving plants Aquatic animals
40
What trees can be found at Studland?
Birch
41
What water loving plants can be found at Studland dune slack?
Boy myrtle
42
What aquatic animals can be found at Studland dune slack?
Ducks
43
Has Studland got a climax community?
It has a climatic climax community and and the area of Studland Heath would take over the area if trees were not deliberately cut.
44
What are the trees deliberately cut at Studland Heath?
To maintain the diversity of the habitats.
45
What are sand dunes?
These are small ridges or hills of sand that are found at the top of a beach, above the usual maximum reach of waves.
46
Why are sand dunes important?
They are important ecosystems.
47
What are sand dunes vulnerable to?
Erosion by both natural and human processes.
48
What is a key characteristic of embryo and fore dunes?
Poor water retention
49
What deposits humus on embryo and fore dunes?
Seaweed
50
How hi are embryo and fore dunes?
About 1m high
51
How much sand is exposed in embryo and fore dunes?
About 80%
52
What is the soil like in embryo and fore dunes?
The soil is alkaline.
53
What are the plant characteristics at embryo and fore dunes?
Long roots with underground shoots Add organic matter which aids water retention Waxy leaves maintain moisture and withstand wind Low to avoid winds High salt tolerance
54
What are the key characteristics of yellow dunes?
They are more water retentive Little vegetation or organic matter Beyond the reach of normal tides Reduced wind speed
55
How high are yellow dunes?
5m high
56
How much sand is exposed in yellow dunes?
About 20%
57
What is the soil like at yellow dunes?
It is less alkali.
58
What are the plant characteristics?
``` Salt tolerant Thrive when buried in sand Leaves are rolled up to reduce moisture loss Long roots Rhizomes stabilise the sand ```
59
What are three example plants that can be found at yellow dunes?
Rag wort Red fescue Sand sedge
60
What are the main characteristics of grey dunes?
Sheltered More vegetation cover Little mobile sand Sand no longer accumulating
61
How much humus is found at grey dunes?
Grey dunes have a high humus content.
62
How high are grey dunes?
They can reach heights of up to 20m.
63
How much sand is exposed at grey dunes?
Less that 10% of the sand is exposed.
64
What type of plant is there less of at grey dunes?
There is less marram.
65
What makes grey dunes grey?
Surface lichen
66
What are the two key plant characteristics at grey dunes?
Higher species diversity | Mainly perennials
67
What are dune slacks?
These are depressions in the dunes where the water table is on or near the surface.
68
What causes the depressions in dune slacks?
The calm air behind the dunes.
69
What is the soil like at dune slacks?
Damp and acidic
70
What are the plants like at dune slacks?
Plants that are also found in fresh water wetlands.
71
Give 3 example plants that can be found at dune slacks.
Rushes Phragmite reeds Big cotton
72
What are the characteristics of Heath/woodlands?
``` The supply of sand is cut off or reduced. Well sheltered from winds Lots of humus Nutrient rich Minimal influence by maritime. ```
73
What is the soil like at heaths and woodlands?
It is acidic
74
What are the two plant characteristics?
Perennials | Scattered trees
75
Give two example plants that can be found at Heath/ woodlands.
Heather | Sea buckthorn
76
What is meant by ridges?
These are sequences of dune parallel to the coastline.
77
What are blowouts?
These form when fragile sand dunes have their vegetation destroyed by grazing animals such as by rabbits and human activity.
78
What type of human activity can damage sand dunes?
Trampling