Crowded Coasts 2.3.3 Flashcards
Enquiry Question: How can coastlines be managed in a sustainable way? (45 cards)
What is plant succession in a coastal environment?
It is the gradual development of vegetation in coastal zones, starting with pioneer species and ending with a climax community.
Why is succession important for stabilising coastal landforms?
It helps bind soil, trap sediment, and protect against wind and wave erosion.
What are pioneer plants, and what conditions can they tolerate?
They are the first species to colonise bare sand or mud; they tolerate high salinity, wind, and poor nutrients.
Describe the role of marram grass in dune succession.
Marram grass stabilises dunes with deep roots and traps more sand, allowing dune growth.
What physical feature initiates embryo dune formation?
Sand accumulates around obstacles like driftwood or shingle ridges.
How do yellow dunes differ from embryo dunes?
Yellow dunes are larger, contain more sand, and start to support vegetation.
What changes in soil and vegetation occur in grey dunes?
Soil becomes richer with organic matter; more diverse vegetation grows.
What is a dune slack and when does it form?
A low-lying area between dunes where the water table is close to the surface, forming wetland conditions.
How does vegetation succession increase biodiversity on dunes?
As soil improves, more species can grow, increasing plant and animal diversity.
What long-term benefits does plant succession provide to the coastal zone?
It protects inland areas from erosion, creates habitats, and reduces flood risk
What is the first stage of salt marsh succession?
The algal stage, where algae bind mud and stabilise the surface.
Which plants dominate during the pioneer stage of a salt marsh?
Cord grass and glasswort, which tolerate salty, muddy conditions.
How does vegetation contribute to the rise of salt marsh height over time?
As plants trap sediment and organic matter accumulates, the marsh builds up.
What characterises the stabilisation stage in salt marshes?
More vegetation like sea thrift and sea lavender grows; less frequent submergence.
What is climax vegetation in a salt marsh and how often is it submerged?
Species like red fescue and sedges grow; only submerged once or twice a year.
What conditions are needed for mangrove growth?
Warm tropical climates, saline water, and low-energy sheltered coastlines.
How do mangroves protect coastlines from storm surges?
Their roots absorb wave energy and bind coastal sediments.
Name two ways mangroves support local economies.
They provide fish nurseries and timber for construction.
What makes mangrove wood commercially valuable?
It is water-resistant and rot-resistant, making it ideal for local use.
How do coral reefs contribute to coastal protection?
They act as natural breakwaters, absorbing wave energy before it hits the shore.
What is coral bleaching and what causes it?
It is the loss of algae from coral due to rising sea temperatures, which can kill the reefs.
How are coral reefs linked to biodiversity and marine food chains?
They support thousands of marine species and serve as breeding and feeding grounds.
What ecosystem services do coral reefs provide for tourism and fishing?
They attract tourists for diving/snorkelling and support local fisheries.
How does rapid urbanisation affect natural coastal ecosystems?
It replaces habitats with concrete, increases pollution, and disrupts sediment balance.
