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There is a huge amount of information available about coral reef health and in particular the mass coral bleaching events that have occurred over the past two years. Two of my previous posts are linked below, but if you scroll to the bottom of the page there are a range of other articles, reports and websites regarding coral bleaching that you might find useful.
Previous posts: Mass coral bleaching events Coral bleaching - reef resilience Students should define the following key terms: - acclimatise - connectivity - recruit - adaptation - natural selection - symbiotic - zoozanthallae - parasite - photosynthesis Answer the questions below. Conduct internet research to find articles and reports which support your answers.
Resources: Coral bleaching - GBRMPA Coral bleaching and the Great Barrier Reef - ARC CoE Coral bleaching: Extreme heat pushes parts of the Great Barrier Reef beyond recovery - ABC Coral bleaching events - AIMS Great Barrier Reef: a "hopping hotspot" - Australian Geographic
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The changes in temperature and associated bleaching are resulting in a different mix of species on the reef. This will impact reefs in the long term. Loss of species Fish, whales, dolphins, sharks, rays and the many other organisms found in reefs rely on the complexity of the ecosystem for survival. Some fish rely on the colour of the corals for camoflauge and the structure of the coral for hiding. Many organisms are unable to carry out normal functions and processes as a result of the increased ocean acidification associated with climate change. Shellfish are less able to create their shells due to increased pH. Slow growing corals will take 100-200 years to recover, meaning that the reef will not exist in the form that we have known it in the past. Dispersal of spawn Ocean warming impacts on the dispersal or coral spawn (eggs). Increased ocean temperatures result in a decline in the dispersal distance of coral spawn from the origin (parent coral) to the destination site. This change in dispersal patterns can impact on species' distribution, abundance or corals in particular areas and genetic diversity across reefs. Changes to dispersal patterns can also impact on the connectivity (interconnections) between different areas of the reef by limiting the areas of reef that particular coral species are located. Poleward shift of species Ocean warming can also result in a poleward shift of species from tropical zones to more temperate zones. Warmer waters are found further from the tropics and species are able to take advantage by increasing their range. In Western Australia, a species of wrasse - cheorodon rebuscens has started to shift its range with displacement of recruits south of its usual habitat. There is evidence of high recruitment at the temperate edge and no recruitment at the tropical edge. The range shift provides limited expansion opportunities, reducing resilience of the species. Irukandji are migrating further south on the Great Barrier Reef as a result of warmer waters and are also having longer seasons in other areas. There have been anecdotal reports of increases in reports of stinging and hospitalisations on islands within the Great Barrier Reef (e.g Fitzroy Island) and snorkellers are being strongly advised to wear stinger suits outside of usual peak Irukandji seasons. Irukandji and associated stingings have also been reported on western side of the southern tip of Frazer Island where they haven't previously been found. Symbiotic relationships Following bleaching events or even natural disasters, corals can become overgrown with algae, making it difficult for coral recruits to settle and grow. The mix species on a reef can impact on how resilient that particular reefs is. For example in Moorea in French Polynesia experienced high coral mortality in the 1980s. Recovery of the reef was enabled in part as a result of grazing fish such as parrot fish removing some of the algae in the process of eating corals. In this way the biodiversity of the reef contributed to high levels of resilience on the reef in comparison to some other reefs globally. The scale of the bleaching on GBR make it unlikely that these types of natural processes will have much of an impact on recovery. Below: A parrot fish on the outer reef, 2015.   I had the pleasure of hearing Professor Terry Hughes present as part of the Sydney Ideas talks being run by the University of Sydney. Professor Hughes is Centre Director at the ARC Centre for Excellence for Coral Reef Studies at James Cook University. I use the term "pleasure" because I am a big fan of his work, and think that some of the visual representations that he has created have been incredibly powerful in explaining coral bleaching to students, but actually the information presented was really quite depressing. Image left: Photograph of bleached corals at Fitzroy Island April 2017. Hughes described some of the main drivers of degradation of coral reefs: pollution, overfishing and climate change. He explained how overfishing had resulted in the reduction of stock sizes for different species in the past century, how pollution from inland activities resulted in coral mortalities and encroachment of different ecosystems like mudflats in areas previously thriving with corals. He went on to say that the scale and extent of these changes were being dwarfed by the immediate and irreparable changes being wrought by back to back bleaching events. Below right: Bleached coral on Fitzroy Island April 2017.
Mass bleaching events have occurred in both 2016 and 2017 as a result of increased ocean temperatures. The bleaching is as a result of corals expelling their symbiotic algae. Coral bleaching tends to occur after the summer temperature maximum, and relates to where the hottest water is. In 2016 coral bleaching severely bleached the northern third of the Great Barrier Reef, the middle section was bleached to a lesser extent, but still quite severely, while the bottom third of the reef largely escaped bleaching in 2016. This was established by the surveying of 1160 reefs through 9000km of aerial surveys, and 75 hours of flying. The 2017 bleaching event impacted the central section of the GBR, while the bottom third is again largely unbleached. Cycle Debbie, a chance weather event, lowered temperatures in the southern part of the reef, which contributed to reducing bleaching in this section. The combination of both the 2016 and 2017 bleaching events has been extremely damaging. There have been reports that the recent cyclone that affected Queensland, Cyclone Debbie may play a role in reducing the impact of coral bleaching. It was reported in the Cairns Post that the cyclone would reduce ocean temperatures, bring cooler waters to the surface and increase cloud cover, thus reducing bleaching, providing stressed corals with an opportunity to recover. The Cairns Post reported that temperatures off Lizard Island had dropped by three degrees and that this would reduce the severity of bleaching. It also provided quotes from a free diver describing the amazing colours and marine life of the outer reef. In reality, as already stated Lizard Island and the top third of the Great Barrier Reef were already severely affected by bleaching in 2016 (well before Cyclone Debbie) and were again affected in 2017. In any case, the path of the cyclone was too far south to have any real impact on areas severely affected by bleaching. Will the Great Barrier Reef recover? There is a narrow opportunity for limited recovery, but the Great Barrier Reef as we know it (complexity, extent, etc) is already dead in many areas. It will continue to exist but with reduced biodiversity. Any real opportunities to protect the reef as it remains is reliant on halting temperature increases and stabilising the climate through reducing reliance on fossil fuels. With negotiations underway between the Australian Government and Adani for for the creation of the Marmichael mines this seems highly unlikely. For more detail on coral bleaching see my article in this term's GTA NSW HSC edition of the Bulletin. http://www.gtansw.org.au Symbiotic relationships Symbiosis is a long term relationship between two organisms. There are three types of symbiotic relationship: mutualism (where both organisms benefit), commensalism (where one species benefits, but there is no benefit or harm to the other species), and parasitism (where one organism benefits tot he detriment of the other). There are many examples of symbiosis on coral reefs. Corals and zooxanthallae The relationship between the corals and the zooxanthallae is beneficial to both. Corals provide the zooxanthallae with an environment suitable for survival. It is moist and the coral's waste gives energy to the zooxanthallae. Through the process of photosynthesis the zooxanthallae produce compounds that the coral use for food. Clownfish and Sea Anemones The Sea Anemones have tentacles with stinging cells. These stinging cells kill many organisms and it is in this way the anemones get their food. Clownfish hide in amongst the tentacles of the Sea Anemone, but are not harmed by them. In this way the clownfish are protected from other predators. Occasionally the Clownfish will catch food for the Sea Anemone. Sharks and Remoras Sharks sometimes get parasites which live on the external surface of the shark. Remoras are cleaner fish, and they attach themselves to the shark and kill the parasites. When the shark feeds the Remora are able to eat the scraps from the feed. Watch the videos below, and take notes about the following symbiotic relationships: - Christmas tree worms and porites corals - Coral shrimps and corals - Goby shrimp and Hawaiian Shrimp Goby - Cleaner Wrasse and cleaning stations •Coral Reefs support a large number of plants and animals. •Coral Reefs are built by millions of tiny animals called polyps. •Some coral polyp species receive more than 60% of their food from algae. •Each coral colony begins life as a single polyp, which then reproduces itself as a single polyp, which then reproduces itself by budding or by dividing. Types of coral reefs There are eight main categories of corals: branching, corals with meandering ridges and valleys, massive or thick colonies, thin plates and crusts, solitary/isolated/free-living corals, coral with large, daytime expanded polyps, column corals and blue/fir/organ pipe/lace corals. Some examples of coral are found below:
Where are coral reefs found? Special conditions are needed for reef-building corals. Coral reefs will only grow in waters warmer than 18oC, and no deeper than 50metres. Therefore coral reefs are limited to clear, shallow tropical seas found either side of the equator. Corals may not develop properly in waters that receive freshwater runoff or sediments from rivers. This is part of a unit of work for Changing Places - Australia's Urban Future. Lesson 1: Australia's Projected Population Growth Lesson 2: Implications for Future Growth and Sustainability Lesson 3: Sydenham to Bankstown Urban Renewal Precinct Lesson 4: WestConnex - Sydney, Sustainability and Transport Lesson 4: Sydney Sustainability and Transport (Teacher's Notes) Lesson 5: The GreenWay Lesson 5: Deindustrialisation Lesson 6: Create an infographic Lesson 7: Contributing to a Sustainable Urban Future Lesson 7: WestConnex - Protest Movements and Impacts Lesson 7: Conflict Over Dulwich Hill OR See the complete unit on the Changing Places website. Stage 1 of the WestConnex project involves the widening of the M4, a connection between Parramatta Road and the City West Link and new connections at Concord Road. A tunnel will run from the end of the current M4 to the City West Link, M4 East concept design WestConnex Stage 1 WestConnex interactive map Ashfield A section of Ashfield along Parramatta Road was acquired and demolished for WestConnex. The exit to the M4 tunnel will be opposite Bunnings Warehouse near the crossroads of Frederick St/ City West Link and Parramatta Road. Link: WestConnex plan jeered by Ashfield residents Save Ashfield Park Rally Haberfield Some of the issues raised in relation to WestConnex in Haberfield include home acquisitions, destruction of heritage architecture, noise and vibrations for homes adjacent to construction sites, changes to traffic flows and the impact of all of these factors on the nature of the suburb. Links: Haberfield homes acquired for building of WestConnex Three month closure of Ramsay Street Haberfield Talking WestConnex and Mike Baird ignoring compulsory aquisition reforms WestConnex private contractors sell items from heritage homes ahead of demolition WestConnex unused land should be handed back say inner west residents. Residents in Haberfield and Beverley Hills claim WestConnex work is cracking walls of houses near motorway construction sites. What we are facing is the destruction of Haberfield
This is part of a unit of work for Changing Places - Australia's Urban Future.
Lesson 1: Australia's Projected Population Growth Lesson 2: Implications for Future Growth and Sustainability Lesson 3: Sydenham to Bankstown Urban Renewal Precinct Lesson 4: WestConnex - Sydney, Sustainability and Transport Lesson 4: Sydney Sustainability and Transport (Teacher's Notes) Lesson 5: The GreenWay Lesson 5: Deindustrialisation Lesson 6: Create an infographic Lesson 7: Contributing to a Sustainable Urban Future Lesson 7: WestConnex - Protest Movements and Impacts Lesson 7: Conflict Over Dulwich Hill OR See the complete unit on the Changing Places website. Stage 5 Geography - Changing Places In the previous 7-10 syllabus in Environment Issues there was a section of content where students were asked to investigate individual, groups and government responses to an issue. In the new NSW syllabus this has been removed. However, in Stage 4 Changing Places the issue of WestConnex protests (or some other protests) can be used to address the inquiry questions:
Students can examine transport networks as both a cause and consequence of urbanisation (see previous post - WestConnex - Sydney, Sustainability and Transport) Students can also use it to examine the following content dot points:
Below: The St Peters West Connex site.
Stage 6 Geography - Urban Places/Urban Dynamics In a previous post I wrote about how WestConnex could be used as a way of exploring growth, development, future trends and ecological sustainability for a Sydney case study in the urban dynamics section of the HSC course. Another way this issue could be used in this course would be to use it to explore the culture of place of a suburb like Haberfield. There have been a variety of articles regarding the nature of the suburb in terms of heritage architecture, noise, and street life, and how this has and will change as a result of WestConnex. There are also a number of articles regarding the development site at St Peters and the removal of established trees on Sydney Park. This could also be used as a way to ask problematic questions such as: - What is the cost of development?, - What kind of Sydney do we really want? - Do the benefits to the city/commuters outweigh the costs to others? - Will the project really releive traffic in the long term? 
Students can do this through the lense of community protests to examine how different groups and individuals perceive how WestConnex (both a consequence of and a response to urbanisation - i.e a response to traffic congestion, the need for transport infrastructure) impacts their community and/or environment. In the previous syllabus there was a lot of scope to do activities such as mock council meetings, mock letters to Members of Parliament, etc. A simple search on Youtube brings up many recorded meetings regarding the project. This is an ideal scenario to use in class to reenact (or participate in) this process. While NESA/BOSTES has not completed a rewrite of the Civics and Citizenship Australian Curriculum, we can assume it will be relatively similar based on the rewrites of 7-10 History and Geography. In Civics and Citizenship (AC) students examine how citizens participate in direct action and lobbying (Year 8) and how and why individuals and groups participate in and contribute to civic life (Year 9). This provides a perfect example to explore these kinds issues and to build on student knowledge in Civics and Citizenship. Resources Below is a list of links to articles and websites related to WestConnex protests. You will notice that some of these are from media outlets such as Green Left Weekly and Alt Media. In a previous post on WestConnex most of the links I provided were government websites. The two posts together provide a more balanced approach to the issue and any lesson to students should include a range of perspectives and encouraging students to do their own analysis and make their own conclusions. WestConnex: Protesters clash with Police over 800 tree-deaths Protesting businesses in Newtown and Enmore stick it to WestConnex Haberfield homes acquired for building of WestConnex Three month closure of Ramsay Street Haberfield Talking WestConnex and Mike Baird ignoring compulsory aquisition reforms WestConnex private contractors sell items from heritage homes ahead of demolition Clover Moore supports protesters at 24-hour-a-day camping blockade... WestConnex protesters arrested as Sydney Park trees come down. Protesters Clash with WestConnex workers How the 15.4b WestConnex will affect Sydney residents Baird's new protest laws used against WestConnex protesters Protests grow over WestConnex Stop WestConnex WestConnex Action Group Following on from the Legal Studies revision planner is a Geography planner to guide student revision. For my class, I allocated Ecosystems At Risk and Urban Places two weeks each and only gave People and Economic Activity 1 week – this was because my class won't have done the the PEE case study by the time of the Trials. In this planner I have allocated 2 weeks revision for each topic and a week for skills revision. Depending on your students it is also a really good time to emphasise with students the importance of getting the balance right between study, their part-time job, socialising, eating right and exercising. If they can set up the right routines now, they will find it easier to cope when the Trials and HSC exams are on.  
 Examine the Urban Observatory website.
Compare London, Tokyo and New York. Compare different aspects of these cities by choosing different themes from the left hand menu. Population Density and housing density: Describe the population and housing density of London. Where are the densest areas? Are particularly dense areas in a particular part of the city?How is the density spread out across the city - does it spread out radially? is it north/south, etc. How do these results compare with New York and Tokyo? How would you account for the differences? Work - Commercial and Industrial: Describe where the commercial areas of the city are located. Where are the industrial areas located? How does this compare to New York and Tokyo? Account for the differences. Movement - Road speed, traffic and airports: How would you compare the road speeds and traffic evident between the three cities? Why would this be the case? How would it impact on the way the city functions? What information can we gather about the importance of the airports in New York and London? Account for the difference in flight numbers between the two cities.
Your task is to create a presentation for your class which explains how one land use (residential, commercial or industrial) has changed over time. You must discuss each of the following: economic character, nature and location. Your presentation must include:
- statistics which support your key points - at least two maps (to show change over time) - an article which supports what you are stating You must prepare and distribute a two page handout. Your presentation should go for 8-10 minutes and should include a range of simulus (visual aids, etc). Articles: Paying huge Sydney prices for tiny places. Read more... |
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