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Coasts Specification: 2.2.3 Marine processes Candidates should be able to: • Demonstrate an understanding of wave processes in eroding a coastline and re-sorting and depositing materials removed through erosion. Candidates should understand the types of waves and the components of waves, swash and backwash. The erosional processes of wave action should include an understanding of corrasion, hydraulic action, corrosion and attrition. Transport of material along a coastline should be appreciated; onshore and offshore movements together with an understanding of movement along a coastline (longshore drift). The action of wind in shaping coastal sand dunes should also be understood. • Describe and explain the landforms associated with these processes. • Describe the conditions required for the development of coral reefs. • Describe fringing and barrier reefs and atolls. A study should be made of the following coastal landforms: Cliffs, wave-cut platforms, caves, arches, stacks, bay and headland coastlines, beaches, spits and bars, coastal sand dunes and marsh. 2.4 Interrelationships between the natural environment and human activities Candidates should be able to: • Demonstrate an understanding that the natural environment presents hazards and offers opportunities for human activities. Reference should be made to the hazards posed by volcanic eruptions, earthquakes, tropical storms, flooding and drought.
The coast or the coastline is the border between the land and the sea. The coasts are very important because they have many uses for humans, but they are also under threat because of humans.
WHY ARE COASTS IMPORTANT AND HOW ARE THEY USED?
WHY ARE COASTS UNDER THREAT? • Sea level rises caused by global warming. Low lying
• Tourism. There are many resorts along coasts and
• • •
tourists enjoy using the coast e.g. swimming and sunbathing. Sport. Many sport use the coast e.g. sailing, surfing, diving, kite surfing and links golf. Ecosystems. There are many unique ecosystems along the coast like mangroves, sand dunes and estuarine. Also the biodiversity along the coast is varied and unique. Fishing. Oceans are full of fish (although supplies are declining). Many people make their living from catching and selling fish. Aquaculture (seafood farming), also takes place along the coast. Oil and gas reserves. Much of the world's oil and gas is found under the oceans. Ownership of these reserves is very important. Housing. Many people choose to live along the coast because of its beauty and the relaxing lifestyle Industry. Many industries like to locate near the coast because it is easy to trade. Transport. The oceans are used to transport people and goods. Many ports are found in coastal areas and help allow trade between countries. Walkers. Many people enjoy walking, cycling or riding along coastal paths and coastal areas.
• • •
countries like Bangladesh will be particularly vulnerable. Pollution from sewage discharge , but also accidents like the recent BP oil spill in the Gulf of Mexico. Litter. Litter thrown into the sea can also kill animals. Turtles often mistake plastic bags for jellyfish. Overfishing. Many fish stocks around the world are being over fished to dangerous levels. Erosion. Many coastlines are being eroded by stronger storms and also rising seal levels. Tropical storms. Because of rising sea levels, the frequency of storms and magnitude (strength) are increasing causing flooding, storm surges and wind damage. Privatisation. More and more stretches of the beach are privately owned (houses, hotels, etc.). This is making it increasingly hard for locals to access previously open areas. The privatisation of areas is also increasing the cost of land, making it less affordable for many residents.
Waves Waves are formed because of friction between the wind and the sea. Although it appears that water particles in waves are moving forward, in reality it is only the shape and the energy of the wave that is moving. Water particles tend to move up and down in a circular motion. When waves near the coast, the bottom of the wave is slowed by friction with the sea bed. Because the top of the wave is experiencing less friction, it moves faster and eventually topples over the bottom of the wave and breaks. The size of the wave is effected by three factors: • • •
Duration of wind Strength of wind Fetch (the distance that a wave travels)
Wave Terminology Crest: The top of the wave. Trough: The low area in between two waves. Wavelength: The distance between two crests or two troughs. Wave height: The distance between the crest and the trough. Wave Frequency: The number of waves per minute. Velocity: The speed that a wave is traveling. It is influenced by the wind, fetch and depth of water. Swash: The movement of water and load up the beach. Backwash: The movement of water and load back down the beach. ________________________________________________________________________________
Wave Refraction Coastlines are very rarely perfectly straight. Coastlines normally have a series of bays and headlands. As you already know, as waves reach shallower water, the bottom of the waves experience greater friction with sea bed. This greater friction causes the waves to slow down. If you have a series of bays and headland, waves will start to slow down around the headland where the water is shallower, but continue to travel more quickly into the bay area where the water is deeper. Because the section of the wave centred on the headland is travelling slowly and the sections either side are travelling more quickly the wave begins to refract (bend) around the headland. This concentrates the wave energy on the headland and disperses the energy across the bay. _________________________________________________________________________
Destructive waves: Destructive waves have a fairly weak swash because the wave breaks almost vertically. However, it does have a much stronger backwash. Because the backwash is stronger than the swash, destructive waves erode and transport material away from beaches.
Constructive waves: Constructive waves have a strong swash and a much weaker backwash. Because the swash is stronger than the backwash they tend to deposit material and build beaches up. . ____________________________________________________________________________________ Coastal Erosion (types of erosion) Coasts being at the boundary of the land and the sea are extremely vulnerable to erosion. They are attacked by the immense power of the sea and the weather. Later you will look at one of the fastest eroding coastlines in the world; the Holderness coastline in NE England which is eroding at over 2 metres a year. The main ways that the sea erodes the coast are: Hydraulic Pressure: This is when sea water and air get trapped in cracks. The increasing pressure of the water and air cause the rocks to crack. Corrasion (abrasion): Rocks been thrown into the cliffs by waves and breaking off bits of the cliff. Corrosion (solution): The slight acidity of sea water causing bits of the cliff to dissolve. Attrition: Rocks, sand and stones being thrown into each other by the sea current and waves. Wave Pounding: This is the immense power of waves crashing into cliffs that causing them to weaken. Sub aerial weathering: This is the top of cliffs being attacked by the weather, making the cliffs weaker and less stable. Wind, rain, the heat and the cold can all cause the cliffs to be weathered.
____________________________________________________________________ Watch video on: (i) What is coastal erosion (ii) Deposition & Erosion https://greenfieldgeography.wikispaces.com/IGCSE+Coasts+and+GCSE+Coasts 4
Bays and Headlands Bays and headlands are formed in a very similar way to rapids (rivers topic). They are formed when you get alternate layers of hard and soft rock. The sea is able to erode the soft rock a lot quicker than the hard rock making a bay. The harder rock forms a headland. Bay: An indented area of land normally found between two headlands. Bays are usually more sheltered so there is less erosive power, meaning you often find beaches in bays. Headland: A piece of land that sticks out into the sea. Waves refract around headlands so they experience a lot of erosion forming features like arches and stacks (see below).
_______________________________________________________________________________ Wave Cut Notch and Wave Cut Platform Wave cut platforms are made in a similar ways to waterfalls and gorges (rivers topic). At high tide the power of the sea attacks and erodes the bottom of the cliff. Over time this erosion creates a wave cut notch (basically an eroded hole at the bottom of the cliff). As the wave cut notch gets bigger, the weight of rock above the notch gets greater. Eventually the cliff can not support its own weight and it collapses. The process then starts again, with the erosion of the sea making a new wave cut notch. As the process continues the cliff starts to move backwards (retreat). Because the cliff is moving backwards a wave cut platform (an expanse of bare rock) is created. Wave cut platforms are only visible at low tide.
Caves, Arches, Stacks and Stumps Caves, arches, stacks and stumps are usually found on headlands, where wave refraction is causing erosion on three sides. The waves always look for weaknesses in the headland (cracks and joints). If they find a crack or a joint they will start attacking it. Hydraulic pressure will be the main type of erosion. Overtime the crack may turn into a cave. Slowly the cave will get bigger and cut all the way through the headland, making an arch. As the arch gets bigger the weight of the arch roof gets too great and it collapses, leaving a stack. The stack is then eroded by the sea and weathered from the air leaving a stump. Blowhole: Sometimes the sea may erode through to the top of the headland (following a large crack). If this happens a blowhole is created.
Transportation (longshore drift) Longshore Drift: This is the process of waves moving (transporting) material (load) along a coastline. Swash: The waves breaking and traveling up the beach carrying load. Waves will break and the swash will travel in the direction of the wind. Backwash: The waves returning to the sea with load. Waves will take the shortest possible route back to the sea (gravity). Longshore drift only happens when the waves hit the beach at an angle. It is the process of the swash transporting material up the beach at an angle and the backwash returning directly under the force of gravity that causes material to be transported along the beach. Prevailing (or dominant) Wind: This is the direction that the wind normally hits a coastline. Groynes: Groynes are wooden or concrete fences (walls) placed out into the sea to stop longshore drift happening. Sea currents: Currents are the movement of water caused by differences in temperature, changes in wind or tides. Currents can be extremely strong and can transport large amount of material. Saltation: The wind can also transport sand and even small stones across a beach. The process of the wind bouncing sand and small stones across a beach is known as saltation.
Tides Tides: Tides are the twice daily movement of the sea in and out. Tides are constant and are caused by the gravitational pull of the moon. Some tidal ranges can only be a few metres, others can be several kilometres. Tidal Range (or intertidal zone): The difference or area between high tide and low tide. Spring Tides: When the moon and the sun are in complete alignment you get particularly high and low tides. Neap Tides: When the moon and sun are aligned at right angles to each other so the gravitational pull of the moon and the sun are pulling in different directions. This makes for lower high and low tides.
Depositional Landforms Spits, bars and tombolos are all made by a combination of longshore drift and deposition. They are collectively known as depositional landforms. Spits: A spit is a long thin stretch of sand connected to the mainland but stretching out into the sea. Spits are formed in areas of calmer water where the sea has less energy. They are normally found near the mouths of rivers where the coastline changes direction creating some protection. Longshore drift happens in the direction of the prevailing (dominant) wind. When the direction of the coast changes, longshore drift does not stop, but continues out into the sea. If the sea has less energy (because it is protected), material is deposited instead of transported. If deposition is greater than erosion, then overtime a spit will build up. The end of the spit is usually hooked because of occasional winds and storms that blow in the opposite direction of the prevailing wind. Salt marsh: A low energy, intertidal ecosystem that develops behind a spit. The salt marsh will have some salt resistant vegetation. 7
Tombolo: A spit that joins the mainland with an island. Mainland: The main land mass of an area. Strangely the UK is described as an island within Europe and the world. However, when you just talk about the UK you would describe the main island as the mainland. Island: A small body of land found in oceans and seas. Bar: A spit that connects two headlands or runs across the face of a small cove (bay). Lagoon: The salt water lake that develops behind the bar. Overtime the lagoon will become smaller as deposition takes place.
Changing Sea Levels: Sea levels are not constant. Over millions of years sea levels have moved up and down. Millions of years ago the sea levels were so low that the UK was attached to Europe by land. Although you don't need to know the exact causes and effects, there are two types of sea level change. Eustatic Changes: These are global changes when the whole level of the sea either rises or falls. Generally speaking, during ice ages, sea levels will fall and during warmer periods, like today, sea level will rise. The changes are all to do with the amount of ice held in glaciers and ice shelves. Isostatic Changes: These are local changes, when the level of the land changes relative to the level of the sea. The most common cause is land rebounding after the pressure release of melting ice after the last ice age. Scotland in the UK is rebounding after 2 kilometres of ice melted after the last age, removing a huge amount of weight. ________________________________________________________________________________
Beaches and Sand Dunes Beach: The beach is the accumulation of sand between the lowest spring tides and the highest spring tides. Beaches can be made out of sand, shingle and/or pebbles. Beaches receive their material from longshore drift, constructive waves, cliff erosion and river discharge. Beaches cane be divided into backshore, offshore and foreshore. The backshore is the area above the normal high tide level, the foreshore is the area in between normal high and low tide and offshore is the area below the normal low tide.
Berm: The berm is a ridge (long thin hill) that forms at the top of the beach. It is the highest section of the beach and is basically sand accumulated on the strand line (twigs, litter, seaweed, etc. deposited at high tide). Intertidal zone: The area of land between high tide and low tide. Strand line: The material (seaweed, driftwood) that is deposited by the sea at furthest point of the high tide ______________________________________________________________________________ Sand Dunes are very dynamic, which means they are constantly changing. Sand dunes are found behind berms and are basically an extension of the beach. They are formed by dry sand being blown up the beach. Embryo Dune: Embryo dunes are the starting dunes of sand dunes. They form in the sheltered area behind the berm and strand line. Foredunes: Small embryo dunes can join to make foredunes. Foredunes tend to be very yellow because they only have limited vegetation so no real humus layer develops. Yellow Dunes: Sea couch and marram grass begin to grow on the foredunes so they become more stable and grow. As the dune grows and the vegetation develops a humus layer develops. Grey Dunes: A developing humus layers starts changing the colour of the dune from yellow to grey. Mature dunes: As the humus layers grows more, the dunes can sustain more plants, flowers and even trees. Dune slack: As the size of the dunes develop water can collect between the dunes. Marsh plants can grow in these wet areas. Blowout: A blowout is a depression or hole in the dune caused by the wind. Humus: Is the layer of decaying plant and animal matter that adds nutrients to the ground. Succession: The changing types of plants from basic sea couch to trees is known as succession. Water table: The line between saturated and unsaturated ground.
Saltmarshes Saltmarshes are usually found behind spits, in estuaries or on low energy coastlines. Because there areas tend to have low levels of energy, deposition exceeds erosion. The continued deposition means mudbanks are formed and they are exposed at low tide. Salt and water resistant grass is able to grow on these mudbanks, forming saltmarshes. The salt resistant vegetation (halophytic) means more sediment (load) is trapped and water is restricted to channels, rather than the whole saltmarsh. As the height of the saltmarsh increases more types of vegetation are able to colonise (move in) and grow. The area of land that is inundated (covered) by sea water only at high tides and sometimes only spring tides is called the sward zone. Plants in the sward zone can only survive being under sea water for a maximum of four hours a day. _______________________________________________________________________
Coastal Defences Coasts are vulnerable locations that need protecting. They need protecting because of the economic value they bring to areas e.g. fishing, tourism and transport. Coastal erosion is mainly caused by hydraulic pressure, corrosion, corrasion and wave pounding. However, sub-aerial erosion can also play an important role. Areas that are near to sea level and are made from soft rock are particularly vulnerable. If coastal erosion is allowed to happen, coastal roads, ports, holiday resorts, farmland and even whole villages may be lost. Hard Engineering: This building a physical structure, usually out of wood or concrete to protect the coast. Hard engineering is usually more effective, but it can be very expensive and ugly to look at.
Rip-rap: Rip-rap is basically giant boulders placed at the foot (bottom) of cliffs. Rip-rap is designed to absorb the waves energy and protect the cliffs behind. Rip-rap can be effective, but does look ugly, may reduce access to the beach and can be expensive.
Gabion: Gabion also uses large boulders, but this time the boulders are placed in cages. This means that gabion can be installed quickly and again is fairly effective. However, it also looks ugly, reduces access and can be expensive.
Groynes: Groynes are designed to stop longshore drift transporting away beach material. They can be effective in maintaining a beach, but need replacing regularly, look ugly and can cause problems down the coast, because they are not receiving beach material.
Sea wall: Sea walls are made out of concrete are aimed to absorb the waves energy. Sometimes they are recurved to direct the waves energy back out to sea. They can be very effective, but again are expensive, ugly and reduce access.
Breakwater: Breakwaters are built out into the sea. They are a coats first line of defence. Instead of breaking on the coast, waves, break on the breakwater. They are often found around the mouths of rivers and ports. They are expensive and can disrupt shipping and animals.
Revetments: They are similar to sea walls, but often built out of wood. Often found at the foot of cliffs they are designed at absorb the waves energy. Again they need replacing regularly and do not protect against big storms.
Soft Engineering: Rather than building physical structures made out of wood and concrete, soft engineering is working with nature. The results of soft engineering look much more natural and may not even be noticed. The advantage with sot engineering is that it does not ruin the look of the coastline and it can be cheaper. However, the main problem is that most forms of soft engineering cannot withstand strong storms. In fact a hurricane can strip a recently replenished beach of all of its sand.
Dune Stabalisation: Dune stabalisation is planting vegetation on the berm of the beach or on the dunes. By planting vegetation you should be making them more stable (roots) and reducing the moisture content (root uptake).
Beach Nourishment: This is simply adding more sand to the beach. Beaches are natural defences, so by making them bigger, you are creating a natural defence. Sand is sometimes taken from the sea bed or dunes inland.
Cliff Regrading: This means make cliffs less steep. Cliffs often become unstable because of undercutting. By reducing the angle you should reduce the undercutting and the risk of the cliff collapsing.
Beach Drainage: Cliffs often collapse because they become saturated and the increased stress causes them to collapse. By removing some of the excess water you should reduce stress on the cliff.
Managed Retreat: This is not always a popular solution, because it is basically allowing the sea to take back land. Low value land is often chosen to be flooded by the sea. By allowing this you are changing some inland ecosystems by adding salt water.
Cost Benefit Analysis: It is not possible to protect the entire coastline of every country. Therefore, cost-benefit analysis is often carried out to see if the coast is worth protecting. The economic benefit of a coast will be looked at e.g. how many jobs are in the area, how much tax the area pays, the value of the buildings in the area. Then the cost of protecting the area will be looked at e.g. how much a sea wall or rip-rap will cost. If the benefits the area generates are greater than the costs of protecting the area, then it will be protected. However, if the costs of protecting the area are greater than the benefits that it generates, then it probably won't be protected.
Holderness Coast (Location and Background) The Holderness coast is a 61km stretch of coast running from Flamborough Head in the north to Spurn Head (a spit) in the south. The Holderness coast is located in the NE of England. The Holderness coast is one of the fastest eroding coastlines in the world and the fastest eroding in Europe. On average the coast erodes at about 2 metres a year. This might not sound much, but if you multiply 2 metres by 1000 years, then that is 2 km of coastal erosion. The reason the Holderness coast is eroding so quickly because of the local geology. 18,000 years ago the north of England was covered in ice (last ice age). As the ice melted it deposited huge amounts of glacial deposits. These 13
glacial deposits actually extended the Holderness coast out into the sea. However, the glacial deposits (known as boulder clay) that make up the coast are extremely weak and vulnerable to erosion. Since Roman times, the coast has eroded by about 4km and around 30 villages have been washed into the sea, along with hundreds of square kilometres of farmland.
Watch the following video: Holderness Erosion - BBC video clip Dairy farm threatened with erosion - BBC video clip Farm threatened with erosion - BBC video clip
Because the Holderness coast is eroding so quickly, it has become necessary to try and protect the coast from further erosion. Hornsea: Hornsea is the main settlement on the Holderness coasts. It has a population of around 8,500 and is an important holiday destination. Because it generates a large income through tourism, it was decided to protect Hornsea. On the sea front a 3 metre high recurved sea wall was built to absorb and reflect wave energy. Groynes were also placed along the beach to try and prevent longshore drift and keep Hornsea's beach intact. On top of the sea wall, the cliff was also strengthened by building a concrete promenade. The promenade has a road on it, small cafes and shops and seating areas. Mappleton: Mappleton is a small settlement south of Hornsea. It only has a small number of houses, a church, a farm and a small caravan park. Because Mappleton was so small it was decided not to protect it. With no coastal defences, Mappleton was quickly disappearing into the sea. The residents of Mappleton were not happy and protested to the local government, blaming Hornsea's defences on Mappleton's accelerating erosion. The main blame was placed on Hornsea's groynes. Because groynes stop longshore drift, Mappleton was receiving no sediment from up the coast, so its beach was disappearing. The prevailing wind on the Holderness coast, is from the NE so longshore drift goes from north to south. The local government was forced to agree with the finding, so Mappleton was protected with a rock groyne, some rip-rap and the cliff was regraded. Withernsea: Because Hornsea and Mappleton were protected it also became necessary to protect Withernsea further south. Withernsea has been protected with a sea wall, rip-rap and groynes. Easington: With Hornsea, Mappleton and Withernsea all protected, Easington is the next settlement along the coast. Because of defences north of it, its coastline is eroding an accelerating rate. Easington is home to a large natural gas terminal, so decisions on its defence will have to be made soon.
Possible Conflict on the Holderness Coast Because coastlines are in demand, conflicts can often take place. For example the Holderness coast is used a holiday destination, it is used for walking, bird watching, farming, playing golf, living (private residences), transport, farming, fishing, refining oil/gas, Geography fieldtrips, etc. When you have so many groups of people wanting to use the coast, conflict is going to happen occasionally. Conflicts can be looked at, by using a conflict matrix. Download the attachment to see an example of a conflict matrix. A conflict matrix works very simply. You look at each group of players (actors) e.g. fishermen and oil/gas works and decide if they have a conflict of interests. In this case they probably will because oil/gas works may pollute the sea which will effect fish stocks. If they have a conflict you put a tick in the appropriate box, if they don't you put a cross. You may be asked to justify your decisions. Refer to: Holderness Conflict Matrix.docx
Watch Video on: (i) Holderness Erosion (ii) Holderness: Sustainable management of a coastline https://greenfieldgeography.wikispaces.com/IGCSE+Coasts+and+GCSE+Coasts
Coral Reefs A coral reef is a line of coral polyp found in warm shallow seas. Polyp are tiny carnivorous (meat eating) animals. Polyps live in groups called colonies. A polyp has a mouth at one end. The mouth is surrounded by a number of tentacles. These tentacles resemble feet, which is how they get their name ('polyp' is a Greek word meaning 'many feet'). Polyps cannot move from their limestone homes. They mostly feed at night. A polyp reproduces by dividing its own body to form two polyps, or by producing sperm and eggs. Each polyp builds a case of limestone around itself, using calcium from the water. It is like a house, with a floor and walls. This remains after it has died and forms a foundation for another polyp to build a house on, putting a floor on the roof of the old one. When these limestone formations increase, they are called a coral reefs. Coral reefs are very delicate and need the following conditions to form: • • • • • •
Tropical sea conditions (between the two tropics) Warm waters (must be over 18 degrees centigrade year round) Clear water ( no sediment) No pollution Sunlight Water less than 60 metres deep
Fringing Reef: Fringing reefs circle or fringe the coastline or islands. They are often protected by barrier reefs further out to sea, so the plants and animals that live in fringing reefs are suited to low wave energy environments. Barrier Reef: These occur further from the sea and are commonly separated from the mainland or island by a deep lagoon. Barrier reefs are normally older and wider than fringing reefs. The Great Barrier reef in Eastern Australia is a barrier reef and stretches for 1600km. Atoll: They rise from submerged volcanoes. They are similar to barrier reefs in terms of biodiversity and form. However, they are confined to submerged oceanic islands, unlike barrier islands which can follow continental coastlines e.g. Great Barrier Reef.
BENEFITS OF CORAL REEFS • • • • • • • • • •
They support 25% of marine species (about 1 million species of plants and animals) They protect coastlines from erosion They form as a natural barrier against tropical storms and even tsunamis (they can absorb energy). Act as natural recycling agent for carbon dioxide from sea and atmosphere They contribute material to the formation of beaches (eroded coral reef) They are source of raw material (coral for jewelery and ornaments) Many species are being found to contain compounds useful in medicine. They benefit the tourism industry because many people like to dive and snorkel over coral reefs They provide important fishing grounds The global value of coral reefs in terms of coastal protection, fishing and tourism has been estimated at $375 billion.
HOW CORAL REEFS ARE BEING DAMAGED • • • •
Rising sea levels mean that the depth of water above coral reefs is increasing. This means that in the future many coral reefs will not receive enough sunlight to survive. Increases in the global climate means that many corals are being bleached. Coral reefs are extremely sensitive to changes in temperature and can bleach (die and turn white) even with only small increases. Hurricanes. Although coral reefs act as a natural defence against tropical storms, they can be severely damaged during tropical storms. Fishing techniques like dynamite, cyanide and trawling can damage corals. Corals are sensitive and take hundreds and thousands of years to grow. Damaging fishing techniques therefore can cause long term damage. Deforestation. As areas of land are deforested, especially in the tropics (Indonesia, Thailand, Philippines) there is greater surface run-off and more sediment enters the rivers and is ultimately discharged into the sea. The increased sediment reduces visibility and means less sunlight reaches the coral. Overfishing. Not only do damaging fishing techniques damage the coral but also overfishing. Coral reefs have very delicate food webs and if you remove elements of the food web, it can upset the balance of the reefs. Pollution. The growth of urban settlements and tourist developments, as well as increased coastal traffic can also cause pollution to reefs. Tourism. Tourism can damage reefs in many ways. Anchors from tourist boats can damage reefs. Motor boat engines can kill animals. Divers can touch and damage coral and tourist developments can release pollution. Marine trade. There are many products, like coral, turtle shells, star fish and sea shells that get removed from corals and sold. This removal of coral and animals damage the reefs.
Coral Reef Management • • • • • • • •
Damaging fishing practices like dynamiting can be banned. It is important that this is enforced or the practices will carry on. Conservation zones where tourists aren’t allowed or there numbers are restricted can be created. Areas where coral reef cannot be farmed can be created Fish stocks can be enhanced and quotas imposed on amount being caught Sewage outlets can be moved downstream of coral reefs Banning the dropping of anchors on coral reef. Reduce the use of fertilisers near coral reefs Finally one of the most important is educating people about why coral reefs are important and how we can protect them. 17