Category Archives: Environment

Cryoconites and climate change

Cryoconite refers to soot, dust and other particulate matter (such as heavy metal pollutants) that has landed on snow and ice. They can occur naturally from activities such as dust-storms, volcanic eruptions and forest fires. They can also be due to human activities such as coal mining, manufacturing operations, land-clearing and desertification. Once liberated, the small particles are carried by air and ocean currents around the world and deposited in some of the most remote polar and mountainous regions of the world.

Despite their ubiquity, the impact of cryoconites in the climate change saga has remained largely understated. However, with more and more effort directed towards mitigating and adapting to global climate change, cryoconites have started attracting the attention they deserve as a key player.

This is because cryoconites have been found to accelerate the impacts of climate change. The small particles of dust and soot reduces albedo – or natural reflectivity of snow and ice. Earth’s polar, snow and ice-covered regions act like natural mirrors by reflect incoming solar radiation back into space. Snow has an albedo of 0.9 while sea-ice has an albedo of 0.8. This mean that they reflect 90% and 80% of sunlight respectively.

Cryoconites blanket the snow and accelerate melting. Reproduced from The Guardian 2015. Image credit: Daniel Beltra

By contrast, snow and ice that has been discoloured by cryoconites can have an albedo as low as 0.2 (or even lower). The low reflectivity of the darker areas means that the absorb more heat from sunlight and melt much quicker compared to brighter areas. As the particles heat up they form small water-filled holes which further adds to the impacts of climate change. It creates a ‘positive feedback’ loop as the water (sea-water has an albedo of 0.06) absorbs more heat from the sun and accelerates the melting process. In some areas, these holes aggregate and form large pools and streams.

Known as ‘moulins’, the fast flowing melt-water carves its way through the surface of the snow and ice. Eventually, the melt-water burrows through the thick ice and reaches the bottom where it acts like a lubricant making it easier for larger bodies of snow and ice to slide, often into the sea.

The melting snow and ice can aggregate together to form large bodies of water. Reproduced from The Guardian (2015). Image credit: Daniel Beltra

Although the loss of sea-ice, snow and glaciers often happen in remote places, their loss has the potential for widespread ecological, cultural and geopolitical ramifications. Greenland, for example is losing an estimated 250 billion tonnes of ice per year. If it was to melt completely, global sea-levels would rise by about six metres. Further, the latest data indicates that the volume of water melting in Greenland caused the underlying tectonic plate to warp. On the opposite end of the world, scientists are concerned about West Antarctic Ice Sheet (known as Larsen C) breaking off. In a matter of days, the rift that is causing the ice-sheet to weaken grew by 11 km.

The Larsen C ice-shelf on the West coast of Antarctica is at risk of breaking off. Reproduced from NASA (2016). Image credit: John Sonntag

If the worst case scenario is realised, then the boundaries of many nations will need to be re-drawn. For some nations such as Tuvalu, the Maldives, and the Kiribati the rising sea-levels are already a fact of life. Wealthy nations with large coastal cities are also expected to suffer. Livelihoods which are intimately dependent on the rivers and streams that are fed by glacial melt such as the Mekong, Yangtze and the Ganges will be lost as the snow and ice retreat. And finally, considering that snow and ice account for 75% of global freshwater, their loss will undermine future resource and food security.

In light of the above, there are a number of strategies that have been put forward to drastically reduce the amount of cryoconites being produced due to human activities. Some strategies to do so include:

  • Setting higher vehicle emission standards
  • Using public transport
  • Promoting the rapid transition away from fossil fuels
  • Encouraging the government to stop the development of new open-cut mines
  • Stopping excessive tree-clearing, particularly, in NSW and QLD
  • Supporting and taking part in tree planting activities
  • Managing large-scale forest (bush) fires

Cryoconites have long remained on the backstage as the world grappled and continues to grapple with mitigating human induced climate change. However, their presence in snow and ice-covered regions of the world has been found to accelerate their loss. Thankfully, many of the strategies identified to address climate change can also have a positive impact in reducing cryoconites.

Gaia: A new look at life on Earth – A short book review

Lovelock’s Gaia: a new look at life on Earth (first edition – 1979) is a seminal piece for contemporary conservationists. The theory grew from his work in the 1970s to develop scientific experiments to find life on Mars. Specifically, what would life on Mars look like? To help answer this question, he turned his thoughts to the existence of life on Earth.

Earthrise: The first image of the Earth from space taken from Apollo 8 in December 1968. To some, this is the most influential, environmental photo ever taken. Image credit: NASA.

According to Lovelock, Gaia is a very complex, hyper-connected entity which has natural checks and balances to help maintain a state of equilibrium. And it is this perfect harmony that is the cauldron that sustains and nourishes life on Earth. For Lovelock our actions can have unintended and unpredictable consequences.

Gaia: a new look at life on Earth is written for a general audience and Lovelock has managed to skillfully blend scientific facts with daily observations. His book is logically structured as each chapter is dedicated to a specific aspect of the Earth’s marine, terrestrial and atmospheric environments. He also uses graphs – albeit sparingly – throughout the book to support his arguments. Indeed, he manages to take the readers on a rich and enlightening journey in his short book.

Sadly, Lovelock’s grand vision of Gaia is muddied in his book. Some sections of the book are repetitive. Despite his use of simple language, some readers might not enjoy Lovelock’s over-reliance on chemistry when explaining the functions of terrestrial, marine and atmospheric environments. His choice of words, such as ‘cybernetics’ and ‘circuits’ when referring to Gaia’s invisible connections might add to the reader’s confusion.

Perhaps, the greatest flaw is not in Lovelock’s writing skills or the structure of the book. It is in the theory itself. His Gaia operates in a perfect system where many forms of pollution such as ozone and greenhouse gases will be naturally dealt with. This view runs the risk of creating a false sense of security given the immense environmental and climate challenges we are facing.

Despite his best efforts though the first publication of Gaia was not well received by the scientific community. His peers considered the theory a heresy – grounded more in theology than in science. However, over the years, his theory has evolved (just like theories do) into something more palatable – a more holistic approach to understanding life on Earth.

Lovelock’s Gaia: a new look at life on Earth (first edition – 1979), is a polarising book. Some conservationists dislike it. Yet there are others who use Gaia as a banner to rally the masses. For me, the desire to read the book was more to get an understanding into the thinking behind Lovelock’s Gaia as well as an intrigue to see how (and if) the theory had evolved since it was first penned. At the very least, I am thankful that Lovelock planted the seeds of thinking about the world in a very different way.

The Hidden Life of Trees – A short book review

Ever wondered what stories your favourite tree was hiding? What secrets you could learn if you could just understand those whispers in the wind? Peter Wohlleben’s book; The hidden life of trees (Figure 1) brings the possibility of communicating with trees a little closer.

Cover of the Hidden Life of Trees
Figure 1: Cover of the Hidden Life of Trees

A forester-turned-conservationist, Wohlleben has spent the better part of two decades managing one of the oldest forests in Hűmmell, Germany. His daily wanderings through his forest has given him an opportunity to observe the social relationships trees have with one another. In his book, he sheds light on how trees talk to each other, how they share resources and defend themselves against pests and even care for the young and the elderly.

It turns out that trees use their root and fungal networks to create the ‘wood wide web’, an organic infrastructure that connects trees in a forest together. In Wohlleben’s book, the forests quickly become a self-regulating entity with Gaia-esk undercurrents.

Indeed, reading Wohlleben’s book makes you feel like he has spent his days exploring Tolkien’s Fangorn Forest (Figure 2). Where one day he wandered too far and too deep and found the Ents. If it were not for the light sprinkling of scientific citations about new research into how trees use sound, taste and smell to communicate, you too would be lost in this fantasy world.

Figure 2: Peter in his beloved forest. Image credit: Sally McGrane, New York Times (2016)
Figure 2: Peter in his beloved forest. Image credit: Sally McGrane, New York Times (2016)

Sadly, some audiences may find Wohlleben’s book a difficult read. There are some parts of the book that come across as being both poorly written and structured as if Wohlleben has failed to completely grasp the complexities of his forest. However, you would be more inclined to forgive him as the book was originally published in German and then later translated into English.

On the whole, Wohlleben’s book seeks to shift the paradigm when it comes to the protecting forests. Specifically, how the current approach to conservation would change if we could understand their ‘language’ and the conversations taking place within a forest. Until then, I suspect a walk in the park or through a forest will never be the same for those who read ‘the hidden life of trees’.

Cooks River hides a little secret

Cooks River is considered to be one of the most polluted urban river systems in NSW. Leaf litter, drink cans, plastics bags, oil runoff are common sights for the locals. When it rains, the situation gets worse as the rubbish snags on the low hanging branches of the casuarina trees and the roots of the mangroves that grow along the banks. The visual pollution and the associated smell can make walking and running along Cooks River an unpleasant experience.

However, despite the pollution, Cooks River hides a little secret. One even some of the locals are not aware of.

To find it, you need to start at Canterbury train station. From there, make your way south across the bridge until you reach the first set of traffic lights. From there, you need to cross to St Mary McKillop Reserve. Then make your way past the tall trees and very slowly, past the gang of noisy sulfur-crested cockatoos. Past the sails of the children’s playground, the rocking horse and the jungle-gym.

You are almost there. Just a little further.

At the end of the little path, past the tall trees lies the secret. A little green oasis known as Cup and Saucer Creek. It was developed as part of Sydney Water’s ‘bank-naturalisation’ project. Bank-naturalisation aims to replace concrete channels, pavements, storm-water drains and lawns with native trees and plants. The construction of Cup and Saucer Creek began in 2010 and took about three months to complete. Twelve months after the project began, it was handed over to Canterbury Council.

Over the past few years, the 27,000 native plants and 40 species of plants introduced around Cup and Saucer Creek have created a vibrant habitat. It is now home to a number of native birds, amphibians, reptiles, fish and insects. In 2014, the Council and the volunteers (Marrickville Mudcrabs) who look after the area installed a native beehive to support the plants in the area. From the Creek, sandstones, rocks and native plants have been used to continue the naturalisation process and link the wetland to Cooks River.

Sights around Cup and Saucer Creek. The stumps make ideal spots for the birds. Sadly, rubbish gets in the wetland from time to time. Image credit, Madeline Rhodes.

The oasis comes complete with its own educational space and interpretive signs about indigenous history. These solidifies the Creek as an important, local greenspace. Adjacent to Cup and Saucer Creek are sandstone seats, ideal for those who want to sit and enjoy a snack as they journey along the banks of Cooks River.

Looking at Cooks River from Cup and Saucer Creek. The new bank naturalisation project has connected the Creek to the River. The sandstones add a great touch and add to the stability of the banks. Image credit, Madeline Rhodes

But Cup and Saucer Creek hides its very own little secrets. Not only does it provide a refuge for local wildlife, it performs another critical function. The Creek was specifically designed to reduce the amount of sediments and pollutants entering Cooks River. This is achieved through a clever way. The Creek is made up of four ponds of varying depths and sizes.

The first pond is the deepest as it receives the bulk of the incoming stormwater. The deep design helps slows the rate at which the stormwater enters the wetland. By slowing the stormwater, the sediments and pollutants begin to settle to the bottom of the pond. The aquatic plants and reeds, together with the algae and bacteria that grow in the ponds helps to break down the sediments and pollutants. By the time the water reaches the fourth pond, it is much cleaner.

One of the four ponds that make up the Creek. It helps slow down the stormwater that flows into it and the aquatic plants and reeds help filter the pollutants. Image credit, Madeline Rhodes.

From pond four, the water flows into Cooks River. The natural filtering and cleaning process is so effective, that Sydney Water estimates that 5 tonnes of sediment, 40kg of phosphorus and 130kg of nitrogen are diverted from Cooks River by Cup and Saucer Creek alone.

The Creek is a great example of the positive impacts that bank-naturalisation programs can have on local water catchments. A once grassy lawn that has been transformed into a thriving and vibrant ecosystem. More projects like Cup and Saucer Creek are needed along the banks of the Cooks River. Ultimately, they need to be connected to form a green corridor. One that not only cleans and filters the water but also provide a habitat for the local wildlife. Doing so will go a long way to help the Inner West Council achieve its goal of making parts of the Cooks River swimmable.

Until then, Cup and Saucer Creek will be one of Cooks River’s best kept secrets. One that many of the locals do not know about. And the ones that do, want to keep it a secret. At least a little longer. 

Corroboree Frogs – the rarest of them all

With distinct yellow and black markings, the Corroboree frog (Pseudophryne corroboree) is one of the most iconic, frog species in Australia. They occur as two species (the Northern Corroboree Frog and the Southern Corroboree Frog) and are only found in Australia’s alpine region – around Mt Kosciuszko National Park. When fully grown, the Corroboree frogs are about 3cm in length and have a lifespan of between 8 – 10 years. Unlike most other species of frogs, the Corroboree frogs walk and are thought to be the only species to produce their own toxins. This means that these little frogs do not have any natural predators.

corroboree-frog-on-moss
Corroboree frog walking on moss. Image reproduced from Jean-Paul Farrero.

The Corroboree frog also has the distinction of being one of the rarest frogs in the world. At one point, its population in the wild was thought to be less than a hundred. In 2013, no breeding was recorded by conservationists. Concern for their survival has led to the Corroboree frogs being listed as ‘critically endangered’ by the IUCN and under the EPBC Act (1999). The frogs are also listed as ‘endangered’ under the NSW Threatened Species Act (1995) and the ACT Nature Conservation Act (2014).

The survival of Corroboree frogs in the wild is undermined by a number of interrelated factors. The first is the natural breeding cycle. It takes the frogs between 3 – 4 years to reach sexual maturity. Mating occurs over the summer months when the females lay about 40 eggs in the alpine bogs and ponds. By frog standards, 40 eggs is considered a very small clutch size. Once the eggs are laid, they develop into tadpoles but do not hatch until the rainy autumn months.

corroboree-frog-habitat
Alpine habitat at Mount Kosciuszko National Park where the Corroboree frogs live. Image reproduced from Jean-Paul Ferrero.

The reliance on the rainy season makes the frogs vulnerable to the impacts of climate change. The altered rainfall patterns will interfere with the hatching of Corroboree tadpoles, making it harder to maintain a healthy, functioning population. Further, the warmer, hotter global temperatures means that alpine areas will continue to shrink, restricting the frog’s habitat range.

Chytrid – the invisible killer

Breeding and climate change aside, Corroboree frogs are threatened by something more sinister and insidious. An invisible predator that has slowly spread itself across Europe, Africa, America and Asia, and decimated many species of frogs. Not much is known about the origins of the chytrid fungus (Bactrochochytrium dendobatidis). There is consensus that globalisation has made the spread of the fungus from one country to another easier. Once introduced into an uninfected environment, the chytrid spreads in one of two ways. Firstly, through direct contact between infected individuals. Secondly, the fungal spores themselves spread through water.

The fungus attaches itself to keratin, the protein component of skin and interferes with osmosis – the frog’s ability to breathe through its skin. Since it first emerged in 1993, the fungus has gone onto infect ten species of Australian frogs. While some species such as the Corroboree frog titter on the brink, others have succumb to the chytrid fungus. The current extinction list includes; the Southern and Northern Gastric-brooding frog, the Sharp-snouted day frog and the Southern day frog.

There are also some species such as the Common Eastern Froglet (Crinia signifiera) and the Alpine Tree Frog (Litoria verreauxii alpina) which are thought to act as reservoirs for the chytrid fungus. The reservoirs provide a safe hiding space for the chytrid, while also helping transport the fungus to new locations.  

Both reservoir species, have habitat ranges that overlap with the Corroboree frogs. This means that preventing the contamination of healthy populations and containing the spread of the chytrid difficult. The eradication of the fungus from the environment is made difficult by its affinity to cold, wet environments. This makes the alpine region of Mt Kosciuszko National Park a stronghold for the invisible killers and the Corroboree frogs easy targets.

Conservation response – the silver lining

Even though the plight of the Corroboree frog seems dire, there are some reasons for optimism. Firstly, the chytrid’s strength – its ability to bind to the protein keratin also happens to be a weakness. This is because during their egg and tadpole stage, frogs lack keratin. In other words, they are infection free.

corroboree-frog-eggs
Corroboree frogs eggs. Image reproduced from Lydia Fucsko (2011).

Over the past decade, a dedicated, captive breeding program between Taronga Zoo, Melbourne Zoo, Healesville Sanctuary, Tidbinbilla Nature Reserve and the Amphibian Research Centre has been capitalising on this.

Infection free enclosure. Image credit: McFadden (2014)
Infection free enclosure where Corroboree frogs are kept in the wild. Image credit: McFadden (2014)

The primary aim of the program is to create an infection free, insurance population. At Taronga Zoo, the carefully regulated room used for keeping and breeding the Corroboree frogs also serves as an exhibition and education space. Thus far, the program appears to be successful. The eggs and tadpoles collected from the captive frogs are being introduced into the wild. To enhance their survival, they are released in remote, alpine areas that are infection free. These efforts have seen numbers slowly climb from a few hundred to about two thousand. Having an insurance population also gives conservationists hope. A hope that it buys valuable research time in which some sort of solution(s) to completely halting or eradicating the chytrid fungus at the molecular level.

The Corroboree frog, with its distinct yellow and black markings is an iconic Australian species. One that has been pushed to the brink of extinction by a silent killer that has slowly spread across the globe. Some species of frogs have been entirely decimated, while others are slowly being lost. A few years ago, the Corroboree frogs were thought to be one of the rarest of species in the world. However, a dedicated and long-term captive breeding program in Australia has helped to create an insurance population of Corroboree frogs that are infection free. Its success is helping boost numbers in the wild as well as buying valuable time so that a solution to the fungus can be found.

 

Tips on creating a habitat garden

These days it seems like everyone is into gardening. Being outdoors, getting your hands dirty and growing your own food is an easy way for us to reconnect with nature. The associated health and wellbeing benefits of gardening have also been widely recognised and promoted. This desire to live off the land is reflected in the popularity of programs such as Gardening Australia and the Gourmet Farmer as well as nature-care campaigns like National Tree Day and the Winter BeardsOn Challenge.

Many of us are now turning our front yards, backyards, verge spaces, community lots and even balconies into herbs, vegetables and fruit gardens. Growing our own produce helps us save money (particularly for those living in expensive Sydney) and reduce our environmental footprint. However, I think that it is a missed opportunity to have a garden that is exclusively used for the production of fruits and vegetables. I believe that with some simple tips such as those outlined below, you can transform your garden into a thriving habitat (depending on how much space is available). One that will boost the productivity of your garden, as well as provide a refuge for native wildlife.

Flowering native plants:

The simplest and most effective way to transform your garden into a lively habitat is by plantings. The best place to get information about ideal natives for your local area would be your council, local nurseries or landcare groups. When planting natives, it is important that they flower throughout the year and that the different plants grow to different heights. Species such as grevilleas, callistemon and leptospermum and native grasses are excellent choices. Plant them next to common garden herbs such as lavender, mint, basil, sage and rosemary. These herbs also flower throughout the year and are good at attracting bees to the garden.

Native garden next to driveway, Milton NSW. Image credit; Hasmukh Chand
Native garden next to driveway, Milton NSW. Image credit; Hasmukh Chand

Beehives:

Beehives have been a very popular addition to gardens, particularly in urban environments. They are small enough to be placed on rooftops, balconies and backyards. For serious hobbyists and gardeners, they can be a timely and often expensive pursuit. However, the honey that bees will produce can be a worthwhile reward. The pollination service that bees provide will increase the productivity of your vegetables and fruits. Because bees can forage large distances, having them in your garden will help other gardens in your area.

Many of us though may not be ready for such an investment or for fear of allergies and unaccepting neighbours. If you do decide that a beehive is something you want in your garden, then locate it in a sunny corner away from the public. It is also incredibly important to check with your local council to see if there are any regulatory requirements for having a beehive on your property and whether it needs to be registered with the State Government. If you cannot afford a beehive, simply drill some holes in your habitat logs which will be ideal for native Australian bees (many of which are solitary and stingless).

Habitat logs:

A thriving habitat garden attracts all sorts of beneficial insects, invertebrates and small mammals. By leaving a habitat log in a sunny corner, you will provide them with a place to sleep, hide, hunt and warm themselves in the sun. Depending on the amount of space available, you can leave logs all over your garden, including under shrubs and foliage. Habitat logs are incredibly important in Australia as many native bee species live in burrows in logs, tree stumps and bark. If there is no room for a habitat log, then mulch can be a great alternative as it will provide a place for bugs, insects and slugs. By adding mulch, you will also help suppress weeds and retain moisture in your garden.

Log in the garden. Holes and rotting bark provide ideal spaces for small insects. Image credit; Hasmukh Chand
Log in the garden. Holes and rotting bark provide ideal spaces for small insects. Image credit; Hasmukh Chand

Habitat rocks:

Habitat rocks perform a similar role to habitat logs. Leave a few rocks around in your garden to get maximum benefits. Larger rocks in sunny areas will provide the ideal spot for any lizards or other reptiles in your garden to warm themselves in the sun.

Watering holes:

Insects, invertebrates, birds and mammals in your garden will need somewhere to drink water. You can use any small, shallow container such as an old plate which is capable of holding water. A partially submerged flat rock or some floating wine corks can also be added to provide somewhere for the insects to land. It is important to keep an eye on the insect watering hole to prevent mosquitoes from using it to lay eggs and for keeping the water filled.

Nest boxes:

Nest boxes are a great way to provide refuge to some of the larger birds and mammals that might be found in your local area. Often, multiple animals might use the same nest box throughout the year. For nest boxes to be effective, they need to be located high up in the tree canopy. As such, it is often best to approach your local council or professionals in your area to have your nest box installed. Nest boxes can either be purchased and there are multiple designs that are suitable for certain birds and mammals. Alternatively, you can build your own nest box by finding tips and instructions online.

Native garden at a private property in Milton NSW. Image credit; Hasmukh Chand
Native garden at a private property in Milton NSW. Image credit; Hasmukh Chand

More green time, less screen time

Planet Ark’s National Tree Day event is considered to be one of the largest, nature-care event in Australia. For over 20 years, the organisation has helped Australians plant more than 20 million trees. The biggest supporters of National Tree Day have been thousands of schools and their students, taking the opportunity to beautify their school grounds and spend a bit of their time outdoors. With an emphasis on local natives, National Tree Day has made a significant contribution to providing habitat for native birds, insects and mammals as well as help absorb and lock away carbon dioxide from the atmosphere.

But it is not just the environment that has benefitted from this 20 year, nation-wide program. Some of the greatest benefits of National Tree Day have been to the people who have participated in the event. More specifically, the simple act of planting trees has helped redefine our relationship with each other as well as with nature. This is incredibly important, given how hyper-connected and technology dominated our lives have become. Over the past five years, Planet Ark has been researching the impacts technology and reduced nature time is having on society.

Some of the key findings include;

  • 1 in 10 children play outside once a week or less
  • 1 in 4 children have never climbed a tree
  • For every hour we spend outdoors, we spend seven indoors watching tv or surfing the internet
  • 51% of Australians feel stressed, depressed and isolated after visiting social media sites

How much time do we need to spend in nature to get the benefits? In the latest research, Planet Ark is prescribing a minimum daily dose of 10 minutes outside. Even 10 minutes a day has been found to be enough to make us ‘happier, healthier, calmer and smarter’, leading to a more fulfilling life. The most profound benefits of nature-contact have been observed among students and children.

Some of the key findings of the latest research include;

  • People living in green areas are 40% less likely to be overweight or obese
  • 77% of teachers have reported that students perform better in standardised tests when outdoor learning is part of the school curriculum
  • People who work in offices with indoor plants are 17% more productive and come up with more ideas

Many other organisations are now recognising the benefits of nature time to those identified and championed by Planet Ark for 20 years. In Canada, the David Suzuki Foundation is promoting the 30 x 30 Challenge, providing thirty creative ideas for doing something nature related everyday for a month. The National Geographic recently published an article examining the positive impacts nature has on our brains. In the UK, The Wild Network is promoting nature play and learning for children. And this movement to encourage people to have more ‘green time’ and less ‘screen time’ is increasingly supported by medical and academic studies.

One of the greatest things about this ‘nature prescription’ is that it very easy and fun (and cheap). So next time you are feeling a little tired, or feel like you cannot concentrate or stuck on an idea, maybe it is time to head outside. Better yet, take the family and friends and enjoy some quality green time. You never know what you might end up finding in the trees.