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
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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
The Spirit of Anzac is a touring exhibition featuring genuine artefacts and stories. To promote the tour the Australian War Memorial and the Australian Government have sent out packages to schools of about 10 Google Cardboard head sets in boxes. You can download the Spirit of Anzac 360 Explorer App from the App Store or Google Play.
The actual headset is already made when it arrives and is packaged within a cover to protect the set. It is quite robust (a little more sturdy than the Google Cardboard sets I have purchased from Ebay before and discusses in previous posts). The lenses are quite large, which will enhance the viewer experience, and some additional velcro and padding should also add to the experience. The App provides an interactive tour of the displays at the Spirit of Anzac exhibition. Students can focus on a particular image and information pops up to explain the display. This isn't as immersive as some other Google Cardboard apps that I have reviewed, but given that it is being sent to schools for free and that the app is free it would be a useful and interesting way to engage students with the displays prior to a visit. The exhibition is showing at:
Explore The Spirit of Anzac - What to Expect Access the Spirit of Anzac Google Cardboard User Guide Some other options of Google Cardboard/Virtual Reality apps that you might like to look at are: War of Words VR This VR experience uses the Seigfried Sassoon poem "The Kiss" as the basis of the experience. It is an animated experience created by BBC Arts. It promotes the feature-length documentary War of Words - Soldier-poets of the Somme. Trench Experience Trench Experience enables the user to experience an authentic trench from world War I. This is like a virtual museum. Diggers Trench VR This VR experience is only available with Oculus Rift - not Google Cardboard. However, I imagine that as Google Cardboard begins to be used more that this will be the type of experiences that we can expect more of. This is more story based. As a new recruit you experience life in the tranches and are able to influence some of the events that unfold in the story. 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.
We all know how stressed students can get leading up to the Trial exams and the actual HSC. Thorough and well-planned preparation is one method to combat some of this stress. So to that end, now is a good time to get students focused on preparing for the Trials. Below is attached a planner which steps the students through revision of the course by completing around half an hour study per day. I have used the topics of Shelter and Family, but you could easily replace these for topics that you have completed. It is also a good idea to give students some ideas on how to study. Often, even some of my most capable students will say that they are not really sure of the study techniques to use. I also included a few ideas at the bottom of the file. I'm sure that you will have plenty more to add. Consider sharing some of your study ideas in the comments section.
See also: Revising for the Trial HSC - Geography
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... Population pressure
Increased population pressures on mainland North Queensland have resulted in increased levels of pollution and physical activities related to tourism on the reef area. Tourism The outstanding beauty of the reef attracts millions of tourists each year. The pressure placed on the reef as a result of tourism includes developments on the shoreline (and associated sewage, rubbish) increase boating activity (including oil spills, coral breakage as a result of boat propellers), and tourist activities (breaking corals while snorkelling, walking on reefs, accessing sensitive areas). Agriculture (particularly Sugar cane farming) Agriculture, especially sugar cane farming on the mainland, has resulted in increased sediment and fertiliser run-off from cane farms. In recent years, a downturn in global prices for sugar cane has resulted in farmers using greater amounts of chemicals. These chemicals run off into coastal streams and result in algal blooms and eutrophication in some areas of fringing coral near the mainland. Sugar cane farmers apply fertilisers containing Nitrogen (N) and Phosphorous (P). Many put on extra fertiliser in case of heavy rain (so it is not all washed away). The introduction of bananas as a crop in the area further increased the use of fertilisers. Of all fertilisers applied, only a third is absorbed by the crops. The rest is either evaporated, enters groundwater or runs off into nearby rivers or canals. Sugar cane crops need water to be drained away quickly. If the crops are left in water the roots will rot. As a result canals were built to drain water away quickly from the crops in case of heavy rain. These canals, or drains, reverse the cycle of how wetlands are meant to function. Rather than regulate and slow the flow of water, the water is quickly moved away from the site and into main river systems. The water rushes off the land carry fertiliser, soil, pesticides, etc. Actually pinpointing the sources of sediment is difficult, but it is believed that most is coming from land which has been tilled and let lie fallow. Sediment is also coming from bank erosion. Since European settlement erosion has accelerated due to clearing of land (less tree to stabilise soil). Due to erosion the river can erode into paddocks. There is believed to be four times more sediment reaching the coast than prior to European settlement, and in some places it is closer to 40 times. Fishing Recreational and commercial fishing have had major impacts on the reef. Commercial prawn fishing accounts of a large proportion of Queensland's Fisheries output. Approximately 6 million kgs of prawns area harvested in a good year. Recreational fishing in the General Use zones of the Great Barrier Reef Marine Park (GBRMP) accounts for 75% of the fin fish taken from the reef each year. Commercial fishing includes fishing for crayfish, finfish, reef fish, barramundi and tuna. An examination of one net which washed ashore showed it contained 14 turtles, a shark and a dugong. Gamefishing has long been an important industry in North Queensland. Pisciculture is a trend involving raising fish in fish farms (e.g. tiger prawns and barrmundi). Dredging Dredging is removing sediment from the bottom of a river bed, harbour, etc and placing it elsewhere. Links: Abbot Point: Dredging dumping permitted within Great Barrier Reef waters Abbot Point approval: Tour operators disappointed by Great Barrier Reef dredge spoil decision Approval of Galilee mega mine leaves Reef strategy in tatters. Landuse impacts on Great Barrier Reef water quality and ecosystem condition Dredging set to swamp decades of Great Barrier Reef protection WWF - Queensland resources sector needs leadership |
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