Presentation on theme: "Focus Area 5A3 Issues in Australian Environments Coastal management."— Presentation transcript:
Focus Area 5A3 Issues in Australian Environments Coastal management
Syllabus: Coastal Management Students learn about: At least TWO geographical issues affecting Australian environments, (one study must include fieldwork): the geographical processes relevant to the issue the perceptions of different groups about the issue individual, group and government responses to the issue decision-making processes involved in the management of the issue management of the issue and implications for sustainability, social justice and equity
Syllabus: Coastal Management Students learn to: explain the interaction of the physical and human elements of the environment recognise the responsibility of the levels of government to the issue propose actions that promote: ▫sustainability ▫social justice ▫equity evaluate the success of individuals, groups and the levels of government in managing the issue
The geographical processes relevant to coastal management Atmospheric processes – caused by such elements as temperature change, storms and the force of the wind. Biotic processes – plant and animal life and the way they interact. Geomorphic processes – uplifting forces within the Earth’s crust, which create sea cliffs or the forces of erosion and deposition. Hydrologic processes – action of the waves, the tides and ocean currents.
Hydrological processes - waves The sea is a powerful force whose constant action can change the shape of coastlines especially the shoreline where the land borders the sea. The size of waves depends on two things: ▫The strength of the wind. ▫The fetch The fetch is the distance a wave travels. The greater the fetch, the larger the wave. The stronger the wind the larger the wave. A wave slows as it approaches a beach. This is the result of friction between the water and the beach. This causes a wave to break. Activity: What determines the size of waves on the shoreline?
Hydrological processes – waves continued When waves enter shallow water the energy in the wave starts to interact with the sea floor. The wave peak eventually travels faster than the wave base causing the wave to break. A broken wave forms the surf and swash zone.
Swash and backwash continued When a wave breaks on a beach you can observe the swash and backwash. The swash moves up the beach at an angle, the backwash returns by gravity straight back to the sea.
Swash and backwash The action of swash and backwash mean the grains of sand can move in a zig-zag motion along a beach. This is known as longshore drift. In stormy weather the action of waves is more destructive hence strips beaches of sand. Over time beaches will build up again as wave action deposits the sand back on the beach.
Waves - definitions Swash - the movement of waves up the beach Backwash - the movement of waves returning back to the sea Long shore drift - the movement of water parallel to the shoreline caused by swash and backwash
Two main types of waves 1.Constructive waves o These waves build beaches. o Each wave is low. o When a wave breaks it carries material up the beach in its swash. o The beach material will then be deposited as the backwash soaks into the sand or slowly drains away. o These waves are most common in summer.
Two main types of waves 2. Destructive waves o These waves destroy beaches. o The waves are usually very high and very frequent. o The back wash has less time to soak into the sand. o The continual hitting of waves on the beach means there is more running water to transport the material out to sea. o These waves are most common in winter.
Hydrological processes - tides At the beach you can observe high and low tides. Tides can be checked in the newspaper daily and on a tide chart. Tides are caused by the gravitational pull of the moon and the sun on the ocean surface. The moon’s pull is much stronger than the sun’s but both can work together. The difference in height between the high and low tide is called the tidal range.
Activity - Hydrological processes – Tides Identify what a tide is. Use a diagram to explain how a tide is caused. Describe the meaning of the term ‘tidal range’ Look up a tide chart in the Sydney Morning Herald for Sydney Tides. ▫When was high tide yesterday? ▫What was the height?
Geomorphic processes - erosion Erosion is destructive waves wearing away the coast.destructive waves Erosional features mainly occur around headlands. They are shaped by three main processes ▫Hydraulic action ▫Corrasion ▫Corrosion
Geomorphic processes – erosion continued Hydraulic action – ▫Waves crash against a headland. ▫When waves hit the base of a cliff air is compressed into cracks. ▫When the wave retreats the air rushes out of the gap. ▫Often this causes cliff material to break away. Blowholes are a common feature formed by hydraulic action.
Geomorphic processes – erosion continued Corrasion / Abrasion – ▫Waves crash over rock shelves. ▫When waves pick up beach material (e.g. pebbles) and hurl them at the base of a cliff. OR ▫Wave action moves rock and other material across the rock shelf ▫Both wear away the rock in an abrasive fashion much the same way as sandpaper can smooth a piece of wood.
Geomorphic processes – erosion continued Corrosion / Solution – ▫When certain types of cliff erode as a result of weak acids in the sea. ▫In rocks along the coast there are minerals like iron. ▫When waves break they wet the rocks. As the rock dries the salt in the sea water crystallises and acts on the minerals in the rock to erode.
Erosion of a headland A headland is an area of hard rock which sticks out into the sea. Headlands form in areas of alternating hard and soft rock. Due to the different nature of the rock erosion occurs at different rates. Less resistant rock (e.g. boulder clay) erodes more rapidly than less resistant rock (e.g. chalk). Where the soft rock erodes bays are formed either side of the headland. As the headland becomes more exposed to the wind and waves the rate of its erosion increases. When headlands erode they create distinct features such as caves, arches, stacks and stumps.
The sequence in the erosion of a headland ▫Stage 1 - Waves attack a weakness in the headland. ▫Stage 2 - A cave is formed. ▫Stage 3 - Eventually the cave erodes through the headland to form an arch. ▫Stage 4 – The roof of the arch collapses leaving a column of rock called a stack. ▫Stage 5 - The stack collapses leaving a stump.
Features of coasts caused by erosion
The Twelve Apostles Activity: Imagine you are a park ranger employed at Port Campbell National Park. Prepare a brief talk including a visual presentation that explains the formation and eventual destruction of the Twelve Apostles. Include: Location of Twelve Apostles How the Twelve Apostles were formed What was London Bridge? What happened to it?
Geomorphic processes - deposition Deposition is when eroded material including sand and sediment is dropped by constructive waves. It happens because wave have less energy. Deposition creates a range of landforms.
Geomorphic processes – Deposition - Beaches The beach is the area between the lowest spring tide level and the point reached by the storm waves in the highest tides. Every beach is different but they are made from the accumulation 0f sand along the shoreline formed from eroded rock and shell material. During storms large quantities of sand are deposited offshore forming sand bars which help limit the impact of erosive waves. The removed sand is eventually returned naturally by smaller constructive waves returning the beach to its former state.
Geomorphic processes – Deposition – Spit Long shore drift moves material along a coastline. Where there is an obstruction or the power of the waves is reduced the material is deposited. Where rivers or estuaries meet the sea deposition often occurs. The sediment which is deposited usually builds up over the years to form a long ridge of material, often sand. This is called a spit. Spurn Head on theSpurn Head Holderness Coast the East Coast of England is an example of this feature.
Geomorphic processes – Deposition – Coastal dunes Coastal dunes are formed by the action of the wind. Once sand is deposited on the beach it can be transported by wind. Sand is blow landward and trapped by low-lying vegetation like coastal spinifex. The fore dune is a store of sand which may be eroded away or may continue to increase in size. The fore dune provides a buffer zone for the fragile dune vegetation located on the hind dune as well as property and developments. It does this by absorbing heavy wave action during storms then rebuilding and restabilising quickly ready for the next period of heavy wave action. Plant communities can quickly recolonise and stabilise the area after periods of erosion, allowing the dune to form again.
Activity – Newspaper Article The local council has decided to buy back residential property located on a headland and a neighbouring fore dune that is subject to severe erosion. Local residents who own the property say the council is depriving them of their spectacular views, relaxed lifestyle and valuable property. Write a newspaper article that evaluates the council’s decision to buy back the properties. ▫ The article should present facts and consider a range of opinions about the issue. ▫The article needs to include an opinion on the property buy-back proposal.
Biotic processes – plant and animal life On the shore plants are typically low and tough as they have to survive the onshore winds and salt spray. Sometimes plants are introduced to stabilise dunes, which can move or be washed away. Plants like the bitou bush (shown below), a native of South Africa, has become a pest and has overrun large areas along the east coast of Australia. Programs to eradicate, get rid of, bitou bush have begun.
Biotic processes – plant and animal life In the water there are many varieties of sea grasses and seaweed. There are also giant kelps, large brown algae that grows just below the low tide mark in dense beds. Kelps (illustrated above) absorb wave action and help defend the shoreline against storms.
Biotic processes – plant and animal life Animal life consists of - beach worms, - planktons (shown above) and - crustaceans (prawns, crabs (shown opposite) and lobsters) which provide food for fish. Small fish are food for sea birds and larger fish.
Activity – Geographical processes Develop a collage defining and illustrating the geographical processes relevant to coasts. Include the following: ▫Biotic processes ▫Geomorphic processes and ▫Hydrologic processes
Environmental impacts on coasts This involves ▫Considering the perceptions of different stakeholders ▫Assessing the decision making process by considering The way the situation has been managed and Reviewing responses the process of management has received ▫Evaluating the entire process in terms of how it reflects upon Australia's level of sustainability, social justice and equity.
Australia’s Coasts In comparison with many countries of the world, Australia possesses an enormous continuous coastline. Australia's coast including islands stretches for about kilometres and comprises over separate beaches. About two-thirds of the population live in the towns and cities that have been built to take advantage of the many benefits the coastline brings.
Human impacts on coasts – Perceptions of different stakeholders Stakeholders or groups with an interest in coasts include: Housing residents Environentalists Governments Community members Boat owners Miners Tourists 1.Housing and development 2.Ports and marinas 3.Stormwater run-off and pollution 4.Sand mining 5.Recreation and tourism
Housing and development This involves: ▫Construction of houses around lagoons and swamps. ▫The use of wetlands for landfills. ▫The development of sand dunes for 'prime' real estate. ▫Recreational purposes have all had negative effects on Australia's coastal areas. The removal of vegetation has: ▫Seen a significant reduction in biodiversity ▫Disrupted the natural processes which form intricate coastal ecosystems.
Housing and development – Beaches Beaches are formed by an ongoing cycle of erosion and deposition of sand. Storms erode beaches of their sand, which is then re-deposited by large waves. When humans use beaches for housing and recreation: ▫The natural cycle is interrupted and sand banks become depleted. ▫Over time beautiful beaches are destroyed. ▫Cliff-top housing, although aesthetically pleasing for home-owners, is also dangerous because of its interference with these natural processes.
Ports and marinas To enhance the navigational potential of coastline, natural channels are widened or deepened by removing earth from the bottom of waterways (a process known as dredging). ▫This destroys the habitats of benthic (bottom-dwelling) organisms that live in the sediment that is removed. Stone breakwaters stretching far out to sea are constructed around ports and marinas to reduce wave impacts and tidal fluctuations. ▫This has the negative consequence of hindering natural erosion and mineral deposition processes.
Stormwater run-off and pollution Vast areas of land covered in concrete and bitumen, particularly in cities, generate enormous amounts of contaminated storm water and rainwater run-off. This pollutes our waterways and damages fragile coastal ecosystems. In addition petroleum-related pollutants are emitted from motorboats, ferries and large ships (20-30 per cent per cent of all marine pollution).
Sand mining In Queensland, northern New South Wales, parts of Western Australia and South Australia, certain minerals found in beach sand are mined for the production of paints and industrial tools. Sand minerals include zircon, ilmenite and rutile. In some areas of WA, calcareous sand beneath seabeds is also mined for the production of limestone and cement. Australia has the world's largest Economic Demonstrated Resource (EDR) of these mineral sands and they are an important source of export earnings. Extraction of sand minerals requires quarrying of beaches, which disrupts the natural cycles that form sand banks and destroys the habitats of many plants and animals.
Recreation and tourism Coastlines have experienced the construction of high-rise resorts, shopping esplanades, playgrounds, golf courses and beach car parks. Development has enhance the lifestyles of residents and the holiday experiences of domestic and overseas tourists but cause significant damage to Australia's precious coastal areas. In less-frequented areas, the use of sand dunes for recreational purposes (for example four-wheel driving) damages sand dune formation and scares away wildlife.
Activity – Develop an imovie to outline the perceptions of different stakeholders to coastal environments Outline - what are the main features of : ▫Views of different stakeholders: Housing residents Environmentalists Governments Community members Boat owners Miners Tourists
Effective management strategies require consideration of the often competing interests, attitudes and values of all stakeholders. In Australia, it has become increasingly apparent that the community, private and government (including local, State/Territory and federal) sectors must integrate their efforts to better utilise, manage and protect the environment. Adopting an integrated approach helps to ensure that environmental management outcomes are sustainable, socially just and equitable.
Stakeholders in environmental management issues At the government level (also known as the public sector) ▫The Federal or Commonwealth Government ▫The State and Territory governments, and ▫Local governments (also called local councils). Power over management and decision-making processes is divided between these three tiers (levels) of government in different ways, depending on the issue at hand.
Stakeholders in environmental management issues At a group level, stakeholders come from the private or community sectors. Private industry stakeholders include ▫Industries based on the commoditisation (the use and sale) of natural resources (such as mining, wood chipping, farming and agriculture) ▫Property and tourism developers ▫Local businesses. Community sector stakeholders include: ▫Non-government organisations (such as The Wilderness Society or The Red Cross) ▫Community centres ▫Educational institutions (such as schools and universities) ▫Churches
Stakeholders in environmental management issues At the individual level every member of society could essentially be considered a stakeholder. This is because environmental issues impact upon each and every one of us in some way, shape or form.
Assessing the decision making process - Environmental planning and decision making Planning is the process of organising our use of the environment. It helps to ensure: ▫Environmental quality is retained while development needs are met. ▫Public and private use of the environment is balanced. Rapid population growth of cities in most countries of the world since WW2 intensified the need for environmental planning. Globalisation lead to economies being modeled on the capitalist system of economic growth which affected the way humans influence the physical and built environments.
Environmental planning and decision making Research needs to be undertaken and used in policy decision making for planning to be effective. Research should be: ▫Comprehensive (cover a range of issues) and ▫Objective not favour the interests of one stakeholder over another.
The role of Environmental Impact Assessments (EIAs) in decision making Environmental impact assessments ▫Predict the impacts a proposed action (for example, the development of a tourist resort) is likely to have on the environment to which it is being applied. ▫Assess the significance of proposed changes to the environment and provide a platform for discussion between different stakeholders.
Integrated environmental management Environmental changes can affect people in positive and negative ways hence careful consideration of the viewpoints of all stakeholders is extremely important. An integrated approach involves governments, private and community groups and individuals integrating their efforts to better utilise, manage and protect the environment.
Integrated environmental management at a government level In July 2000 the Environmental Protection and Biodiversity Conservation Act 1999 (Cth) was passed. The EPBC Act : ▫Represented a move towards greater coordination of Federal, State and Territory efforts to address issues of environmental concern in Australia. ▫Outlines the federal government would take the key leadership role and the authority of the States and Territories has still been upheld. ▫Requires an EIA to be completed before any action that may have a significant impact on the physical or built environment can be approved by the federal government.
Responsibility for Australian coastline ▫The Local, State and Territory Governments are responsible for coastline within three nautical miles (NM) of the shore. ▫The Federal government is responsible for management of waters for 200 nm beyond this. This division of powers can complicate matters because the environmental impacts of activities undertaken in coastal zones do not follow this jurisdictional division.
Integrated Coastal Zone Management In 2003 the federal government endorsed the 'Framework for a National Cooperative Approach to Integrated Coastal Zone Management'. This initiative has been a key milestone in addressing the need for coordinated efforts and tighter monitoring of development in the area of coastal management.
Coastal management Coastal management refers to the use and protection of all coastal areas, which is made up of marine (saltwater) and estuarine (meeting point of fresh and saltwater) ecosystems. In a constant state of evolution, these areas are naturally affected by rainfall, wind, ocean currents, waves and tidal movements.
Human impacts on coasts and resultant environmental issues Our coastal zone houses great potential in terms of its use for commercial, recreational and settlement purposes. It also holds many social and cultural values for both Indigenous and non-Indigenous Australians alike. Much of Australia's coastline has been over developed and over used so sadly, human use and enjoyment of the coast over the past two centuries have greatly disrupted the processes which form its intricate ecosystems.
Human impacts on coasts Human activities have also reduced the biodiversity of our coastlines, which helps them to maintain their health. Small organisms in coastal ecosystems are often the first link in large food chains. The impact of their population reduction or extinction inevitably reverberates throughout the entire chain.
Coastal management strategies Coastal management involves developing strategies designed to protect and preserve the coastal environment. ▫Construction of protective barriers and walls ▫Beach nourishment ▫Coastal dune preservation
Conservation Conservation refers to using the Earth’s resources in a sustainable manner. The Australian Conservation Foundation (ACF) is a non-government organisation involved in conservation issues. The ACF aims to protect, restore and sustain Australian environments by working in collaboration with stakeholders.
Preservation Preservation is concerned with keeping things in their present state or form. Preservation means ▫Reducing human impacts on the physical environment by not touching things that remain in their natural state. ▫Protecting unspoilt ecosystems through the creation of national parks, nature reserves and marine sanctuaries.
Construction of protective barriers and walls – Sea walls There are three basic types of constructed walls: ▫1. Sea walls Used to stop erosion of the coastline and protect property. They often replace the foredune, which is an essential part of the beach erosion– accretion cycle. The scenic appeal of the beach may be reduced by their construction.
Construction of protective barriers and walls - Breakwaters ▫2. Breakwaters Constructed at the entrances to rivers. They extend into the ocean in order to stabilise river entrances and provide safe access for boating by keeping the river entrance clear of sand build-up. They can act to dramatically alter patterns of erosion, transportation and deposition of sand along the coastline.
Construction of protective barriers and walls - Groynes ▫3. Groynes Constructed along beaches (almost at right angles to the shore) to catch sand and make beaches wider. They protrude into the ocean and are designed primarily to slow down the rate of longshore drift. Sand tends to accumulate on one side only, creating a different beach from its natural shape. Traditionally made out of wood or rocks and concrete but often now textilebags filled with sand are being used.
Beach nourishment involves the movement of sand by machines. Large quantities of sand are moved from a point where it accumulates to a point where it has been eroded. It is an expensive beach management technique and needs to be ongoing. Dredging river mouths along the coast is a common source of sand for beach nourishment.
Coastal dune preservation Limiting new developments in coastal dune areas to allow dunes to play their natural role as a buffer between the beach and the land and avoids councils having to build elaborate sea walls to protect property. Constructing fences to control access of pedestrians and vehicles across sand dune areas. This helps stop erosion as trampling vegetation removes the protective covering. Revegetation to help stabilise the dunes when the natural vegetation has been removed.
Activity – Prepare a table of coastal management strategies listing the advantages and disadvantages of each Brief description of management strategy AdvantagesDisadvantages Construction of protective barriers Protects propertyIncreases erosion Beach nourishmentReplenishes lost sand to beaches Expensive and ongoing maintenance Coastal dune preservation Allows dunes to play their natural role Restricts movement on beach
Activity – Prepare a table of coastal management strategies listing the advantages and disadvantages of each - Answers Brief description of management strategy AdvantagesDisadvantages Construction of protective barriers Protects property Maintains river openings Collects sand lost to long-shore drift Increases erosion Unsightly Alters patterns of transportation of sand along beach Unnatural shape given to beach Beach nourishmentReplenishes lost sand to beaches Expensive and ongoing maintenance Coastal dune preservation Allows dunes to play their natural role Stops erosion Stops destabilisation Avoids more expensive structures such as sea walls Restricts movement on beach Limits development
Evaluating the entire process in terms of how it reflects upon Australia's level of sustainability, social justice and equity. This involves an integrated approach to ensure the three primary goals of environmental management can be achieved: 1.Sustainability - achieving environmentally sustainable outcomes. 1.Social justice - ensuring the outcome achieved is socially just (or fair) for all stakeholders. 1.Equity - ensuring decision-making processes through which the outcome is achieved are equitable for all parties involved.
Sustainability, social justice and equity In relation to environmental management explain in your own words the concepts: 1.Sustainability - 2.Social justice 3.Equity -
Sustainability Sustainability is a concept which promotes achieving equality amongst: ▫people in the world's current human populations ('intra- generational equity') ▫and between our current population and those of the future ('inter-generational equity'). Sustainability also relates to striking a balance between our environmental, social and economic needs and interests (sometimes referred to as the 'triple bottom line’) The problem with defining sustainability is interpretations of our environmental, social and economic needs and interests differ considerably between stakeholders.
Sustainable development Sustainable development refers to achieving development that meets the needs of today's population, without hindering the capacity of future generations to achieve their developmental needs. It ensures successive generations have the same access that we do to the features of the environment that enable humans to sustain life on Earth.
Sustainable development Sustainable development in the industrialised world was raised in the 1960s in response to anxiety about the irreversible effects development practices of the consumer and capital-driven economic systems were having on environments.
Sustainable development Sustainable development tends to focus on: ▫The long term impacts of environmental management decisions, not just the immediate effects they will have when they are applied. ▫It considers the impacts decisions have on a variety of communities and ecosystems.
Ecological integrity or national capital Ecological integrity refers to the health and well being of the physical environment. To maintain a high level of natural capital, our renewable and non-renewable natural resources need to be managed wisely. Common examples are: ▫The practice of replanting trees after a section of plantation (not old-growth) forest has been logged for the production of timber. ▫Harnessing energy from the sun to produce solar power, which could replace unsustainable alternatives such as coal and natural gas.
Social justice and equity ‘social capital’ The more socially just (or fair) and equitable (equal) a society is the higher its levels of 'social capital’ or people who have a shared sense of belonging to their community and mutual respect for one another. Achieving sustainability involves having more people concerned about the welfare of other people as well as the environment. The more people who care the greater chance a society has of surviving.
Environmental management in Australia Approaches to managing the environment: ▫ Should promote sustainability ▫ Should be integrated to achieve socially just and equitable outcomes.
Sustainable coastal management The protection of Australia's coastline depends on our capacity to implement sustainable coastal management initiatives. This will need to include such considerations as ▫balancing competing uses of the coast, ▫increasing the amount of protected marine and estuarine reserves, ▫restricting further development in coastal areas ▫and conducting research into making the most of coastal areas in an ecologically sustainable manner.
Factors hindering protection of coasts Lack of tight regulations placed on private sector developers. Different levels of government in Australia manage separate areas of the coastline.
Group and community involvement in coastal management The coast is a popular recreational environment all Australians enjoy hence it is essential they are preserved for future generations. Coastal management schemes need to be: ▫Based on a sound understanding of the natural coastal processes that operate. ▫Must ensure access to coastal areas for the community.
Group and community involvement in coastal management Coastal management schemes require the support of all levels of government as well as community groups. Those involved in coastal management include: ▫The Department of the Environment and Water Resources ▫Griffith Centre for Coastal management ▫International Coastal management ▫Dune Care ▫Coast Care
Activity – Research and evaluate the role of a government and community group in coastal management. Present using comic life. Evaluate Make a judgement based on criteria ▫Griffith Centre for Coastal Management (www.griffith.edu.au/centre/gccm/)www.griffith.edu.au/centre/gccm/ ▫International Coastal management (www.coastalmanagement.com.au/default.htm)www.coastalmanagement.com.au/default.htm ▫The department of the Environment and Water Resources (www.deh.gov.au/coasts)www.deh.gov.au/coasts ▫Dune Care (www.smarta.com.au/dunecare/)www.smarta.com.au/dunecare/
Assess - Make a judgement of value, quality, outcomes, results or size. Develop about 10 slides in power point to present your findings. ▫Generally access management of Collaroy Beach. Outline (indicate the main features of) the impact of natural disasters at Collaroy Beach. Describe (provide characteristics and features) of the management strategies implemented by governments and groups at Collaroy Beach. Assess the management process that has been undertaken at Collaroy Beach.