Geography EQ 2 Flashcards
COASTAL
ECOSYSTEM definition
Refers to areas where there are interactions between the coastal environments and their plant and animal communities.
what are in coastal ecosystems?
They include coral reefs, mangroves, wetlands, estuaries, and bays and are home to many different types of plants and animals.
Ecosystem services
benefits people obtain from ecosystems. Hence benefits that people obtain from coastal ecosystems are termed coastal ecosystem services.
Provisioning Services eg
[only 3]
- Coastal ecosystems provide products such as fish, seafood, water, timber and others.
- wave and tidal energy can be harnessed and converted into electrical energy.
- Timbre for building boats and houses and wood fuel can be obtained from mangrove forests.
Cultural Services
[4]
Coasts provide cultural services, which are non- material benefits such as recreational, aesthetic and spiritual benefits.
- Outdoor activities and tourism relating to coastal areas are common, including sea sports, leisure activities by the beach, beach resorts and eco-tourism.
The sense of beauty people obtain from looking at coasts can provide a rich source of inspiration
Regulating Services
They help stabilize shorelines, prevent flooding and provide protection from storms and natural hazards.
- Coral reefs and mangroves help reduce the impact of shoreline erosion, thus stabilizing the shoreline by protecting the existing shoreline.
Supporting Services
Coastal ecosystems support the production of ecosystem services.
- They sustain a wide range of habitats, such as the mangrove habitat, coral reef habitat and beach
habitat. These natural environments in which plants and animals live are valuable to people and
the living creatures.
How do people use coastal areas? [3]
Housing and transportation
* Tourism and recreation
* Ports, harbours and piers
provisioning, cultural, supporting, maintaining
[3 each EXCEPT maintaining]
provisioning:
-genetic resources
-energy
- harvestable seaweed
cultural:
- Tourism
- Recreation
- Science and Education
supporting:
- Food web
- Water cycle
- Habitats for species
maintaining:
- Storm protection
- Stabilise sediment
Distribution of coral reefs
They are usually found in tropical and sub-tropical seas between the Tropic of Cancer in the northernHemisphere and the Tropic of Capricorn in the southern hemisphere.
WHAT ARE CORAL REEFS?
Coral reefs consist of colonies containing millions of coral animals called polyps.
● The corals and algae enjoy a symbiotic relationship with each other:
○ Polyps provide microscopic algae with nutrients and carbon dioxide.
○ Algae provide the polyps with sugars and oxygen.
CORAL BLEACHING
Corals expel the algae when stressed.
● Triggers of stress include changes in water temperature, pollution etc.
● A bleached coral result.
Factors influencing coral reef growth
Saline conditions 34 to 37 parts per thousand
● Moderate amount of water movement to ensure corals
receive sufficient amount of oxygen
● Sea surface temperature around 21-25oC
● Amount of sunlight which can penetrate up to 60m
underwater
● Turbidity should be low to allow sufficient sunlight to
penetrate
What is the value of coral reef ecosystems?
just the names not the explanation
Economic Value
Environmental value
Supports habitats
Economic Value (coral reefs)
Coral reefs and their nearby land areas are commonly developed as tourist attractions. Jewellery and ornaments made from corals are often favoured as souvenirs by tourists visiting coral reefs, boosting the local economy. erosion.
Environmental value
The value of coral reefs is their crucial role in supporting natural ecosystems, allowing a wide range of marine creatures to breed and grow.
Coral reefs have the ability to absorb wave energy generated in the open seas, thus protecting the adjacent land mass from erosion.
Supports habitats
** not the most important
Habitat to many species basically
Pressures on ecosystem
[name 3]
Recreational use of coasts
Fishing methods
Over-collection
Recreational use of
coasts
Activity, Impacts
activity:
Tourism activities in coastal areas.
impact:
Waste may be discharged into water and stress corals; boat anchors may damage corals.
Fishing methods
Activity, Impacts
Activity:
Dynamite blasting and use of cyanide to stun fish.
Impact:
Coral reef habitat destroyed.
Over-collection
Activity, Impacts
Activity:
Overfishing in reefs and surrounding waters.
Impact:
Depletion of fish disrupts the delicate balance of the ecosystem’s food chain.
WHAT ARE MANGROVES?
Mangroves are salt tolerant sub-tropical plants that grow in conditions that m ostplants are unable to:
○ Saline conditions
○ Constant tidal changes (wet and dry conditions)
○ Soils that are water-logged and oxygen deficient
distribution of mangrovesss
They are mainly located in the sheltered coasts and estuaries between the Tropic of Cancer and the Tropic of Capricorn. However, there are also patches of mangroves further north and south of these tropics.
Environmental conditions affecting growthof mangrobes
Mangroves grow mainly in sheltered coasts and estuaries - should be calm, with no strong waves or tidal currents.
As these areas have low energy waves which allow mud and plant litter to accumulate and mangroves to thrive.
have characteristics which allow them to adapt to the tides, the saline and water-logged environment.
Saline Conditions:
[adaptation]
Adapting to the saline conditions
● Some Mangrove plants are ultrafiltrators
○ Some plants have filtration mechanism to exclude most salts during the absorption of water.
● Some species are salt secretors
○ Special glands to excrete salt
○ Salt is secreted on their leaves which are then removed by wind or rain.
Adapting to the waterlogged soils
horizontal zonation of mangroves. Due to the waterlogged conditions, the soil lacks oxygen and plants need to adapt to such muddy and low-oxygen environments.
3 different zones of mangroves
coastal, middle, inland
coastal zone mangroves
The coastal zone is subjected to regular tides and sediment changes.
● have pencil roots to maintain their stability.
● The pencil roots are exposed during low tides, which allows them to take in oxygen.
middle zone mangroves
The middle zone is also subjected to coastal erosion.
○ prop roots also help to trap sediments to
ensure the growth of the plant.
● Prop roots also help to anchor the trees anchor firmly into the muddy ground
and support the height of the trees.
inland zone mangroves
have kneed roots to anchor them into the soil.
● Soil is also trapped between the kneed roots.
Mangrove Adaptations: To water-
logged soil and tides in terms of fruit
[2 names]
Fruit dispersal
Buoyant fruit
Fruit dispersal
Fruits germinate while they are still on the tree.
- Some fruits are javelin shaped so that they can pierce the soft mud to
germinate and grow
- When the fruits ripen, they fall onto
the ground, take root, and grow.
Buoyant fruit
Buoyant fruit float in water and are
carried a distance before germinating.
3 values of mangrove ecosystems?
names only
Stabilising shorelines
Source of wood
Fodder crops
Stabilising shorelines
The dense network of roots can absorb the energy of the waves, thus slowing down the flow of water.
* The build-up of sediments can help protect coastal areas from erosion by tides, storm waves and tsunamis.
Source of wood
Mangroves provide food for fuel and construction and for producing charcoal.
* Many coastal and indigenous communities rely on this wood for construction material as well as for
fuel.
Fodder crops
Farming communities near mangroves in Indonesia, India, Pakistan and the Middle East cut the
leaves from mangrove trees to feed their sheep, goats and camels.
Demand for fuel wood and
charcoal: pressures on mangroves
Demand for fuel wood and charcoal:
Mangroves cleared for fuel and charcoal, especially in regions with low technology and low-income economies.
IMPACTS:
-Fish breeding grounds are reduced.
-Coasts become more vulnerable to destructive waves and weather elements.
Need for more farming area: presssure on magroves
Need for more farming area:
Flat, well-watered mangroves are converted into paddy fields and shrimp farms.
IMPACTS:
-Fish breeding grounds are reduced.
-Coasts become more vulnerable to destructive waves and weather elements.
Land reclamation: presssure on magroves
Land reclamation:
Coastal land area used for housing, industry and recreational uses.
IMPACTS:
-Coasts become more vulnerable to destructive waves and weather elements.
-Coastal waters are polluted as a result of human activities, inhibiting the growth of mangroves.
