Our cities need more trees, but some commonly planted ones won’t survive climate change


Australian cities could lose some of their most common trees to climate change.
Jamen Percy/Shutterstock

Alessandro Ossola, Macquarie University; Hugh Munro Burley, Macquarie University; Leigh Staas, Macquarie University; Linda Beaumont, Macquarie University; Michelle Leishman, Macquarie University, and Rachael Gallagher, Macquarie University

We need trees in our lives. This past summer, Adelaide experienced the hottest temperature ever recorded in an Australian state capital, hitting 46.6 degrees on January 24. Trees beautify otherwise grey cities and cool our suburbs during heatwaves. But different species have different levels of tolerance of heat, lack of water and other threats posed by climate change.

In a newly published study, we investigated likely climate change impacts on 176 of the most common tree species planted across Australian cities. Our analysis showed more than 70% of these species will experience harsher climatic conditions across Australian cities by 2070. Some of the most commonly planted trees are unlikely to survive these conditions.

The golden wattle might struggle in our northern cities if they get hotter and drier.
Dryas/Wikimedia Commons, CC BY-SA

So which tree species are best suited to particular places? Which species are more likely to thrive, rather than just survive, under a changing climate? Which of our beloved tree species won’t make it?

Tree species growing in warmer cities are more likely to be affected than those in cooler cities. Some species, such as the golden wattle (Acacia longifolia) or the prickly paperbark (Melaleuca styphelioides), might not make it in northern cities, unless we invest precious resources – such as water – to maintain these civic assets. Other species, such as the native frangipani (Hymenosporum flavum) or the tuckeroo (Cupaniopsis anacardioides), will likely become more suitable for planting in southern cities.




Read more:
We’re investing heavily in urban greening, so how are our cities doing?


Why do cities need trees?

Trees are wonderfully effective at improving the microclimate of our cities, which makes tree plantings an effective and efficient way to adapt to climate change. The leaves of trees absorb and dissipate much of the sun’s radiation.

Trees cool air and land by several degrees compared to areas of concrete and asphalt. Swipe the heat map below to see how effectively trees cool down our cities. (Red indicates hotter areas, blue cooler areas.)

Swipe the map to see how much trees cool urban areas. Red indicates hotter areas, blue cooler areas. This temperature map was collected during a heatwave in Adelaide, South Australia, on February 9 2017 by AdaptWest over the cities of West Torrens, Charles Sturt and Port Adelaide-Enfield.
Used with permission of AdaptWest Adelaide (https://www.adaptwest.com.au/mapping/heat-maps)



Read more:
Building cool cities for a hot future


Governments recognise the importance of trees and have developed vital initiatives, such as the national 20 Million Trees program and the 5 Million Trees program in New South Wales. These are important first steps to increase urban tree cover across Australia. But the question arises: are we planting the right tree species?

What does the science say?

Australian cities are blessed with a higher diversity of tree species compared to other cities globally. However, the 30 most commonly planted species make up more than half of Australia’s urban forests.

This poses a great risk for our cities. If we were to lose one or two of these common species, the impact on our urban tree cover would be immense. Consequently, our best insurance is to increase the diversity of our trees.

Species composition of Australia’s urban forests across 60 local government areas. The size of each word is proportional to the number of tree stems recorded for each species.
Alessandro Ossola

Our quest to find climate-ready tree species is only just beginning. Supported by Hort Innovation Australia, the NSW Department of Planning, Industry and Environment, and the Commonwealth government, our team embarked on a project called Which Plant Where in conjunction with researchers at Western Sydney University. Our mission is to find the best plant species for urban landscapes that will be resilient to climate change.

We work with the nursery industry to provide evidence on species’ resilience to extreme heat and drought by testing plants to their limits in research glasshouses. Our work with plant growers and nurseries will inform them on how to adapt their business, by identifying the new challenges posed by climate change, as well as selecting highly diverse palettes of climate-ready species. We advise landscape architects, designers and urban planners about not only the best planting choices, but also how to increase the biodiversity of our cities.




Read more:
For green cities to become mainstream, we need to learn from local success stories and scale up


You can help!

We are committed to do more science in coming years, but you can start making a difference today. Australia’s National Tree Day will be celebrated again this year on Sunday, July 28. It’s a great opportunity to teach our families, communities and businesses about the importance of tree planting and environmental stewardship as key elements of adapting to climate change.

An old Chinese adage says:

The best time to plant a tree was 20 years ago. The second best time is now.

This weekend is your time. The game is simple – head to your closest plant nursery. Ask your local grower about which tree species are suitable for the local growing conditions and pick one you like. Then, plant a tree in your yard, or join one of the many planting events across Australia.

Teach your kids, family and friends about the difference they can start making today – for their future and our common good – one tree at a time. The Conversation

A plant nursery growing a diverse range of tree species for the upcoming planting season.
Alessandro Ossola

Alessandro Ossola, Research Coordinator Centre for Smart Green Cities, Macquarie University; Hugh Munro Burley, Spatial analyst, Macquarie University; Leigh Staas, Associate Director for Engagement & Research Partnerships | Smart Green Cities, Macquarie University; Linda Beaumont, Senior Lecturer, Macquarie University; Michelle Leishman, Distinguished Professor, Head of Department, Macquarie University, and Rachael Gallagher, , Macquarie University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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How we’re helping the western ground parrot survive climate change



A western ground parrot being released with a GPS tracker fitted.
Alan Danks

Shaun Molloy, Edith Cowan University and Robert Davis, Edith Cowan University

When a threatened species is found only in one small area, conservationists often move some individuals to another suitable habitat. This practice, called “translocation”, makes the whole species less vulnerable to threats.

In the past, this approach has worked really well for some species, but climate change is creating new problems. Will the climate change at that location in the future, and will it remain suitable for the species of interest? On the other hand, some regions might become appropriate for a threatened species.

This fundamental question is important in a rapidly changing climate, yet it has seldom featured when picking new areas for translocations.

Western ground parrots live and nest on the ground, making them very vulnerable to foxes and cats.
Alan Danks/DBCA

Saving the western ground parrot

Our recent research applied climate change modelling to translocation decisions for the critically endangered western ground parrot. This species is now restricted to a single population, with probably fewer than 150 birds, on the south coast of Western Australia.

It is enigmatic, in that it lives and nests entirely on the ground, unlike almost all other parrots except the closely related night parrot. And it is one of the many unique animals that make Australia so distinctive from all other parts of the world. But living on the ground has its drawbacks, as the parrot is very vulnerable to foxes and cats.

Its home near the south coast is particularly vulnerable to the effects of climate change. As southwestern Australia becomes warmer and drier, the risk of fire to the parrot increases.

Understanding potential climate change impacts is essential when selecting reintroduction sites. We developed high-precision species distribution models and used these to investigate the effect of climate change on current and historical distributions, and identify locations that will remain, or become, suitable habitat in the future.

Our findings predict that some of the western ground parrot’s former south coast range will become increasingly unsuitable in the future, so reintroductions there may not be a good idea. Four out of 13 potential release sites are likely to become inhospitable to these threatened birds.

On the other hand, many of the former or future sites are likely to become important refuge habitats as the climate continues to warm, and would make an excellent choice for any translocations or reintroductions.

We have given this information to an expert panel, who will use these predictions identify and prioritise areas for management and translocation.

Researchers have radio tracked a small number of birds to learn more about habitat use and movement patterns.
Allan Burbidge

The parrot in the coal mine

Fire is already a significant threat which, combined with predation by feral cats, may have led to the loss of this species from its former home at Fitzgerald River National Park. Many of these threats act together, so they must all be considered and managed alongside climate change.

What’s more, the western ground parrot may be an important indicator for the fate of many other species it currently (or formerly) shares its range with. These include the western whipbird, noisy scrub-bird, and a carnivorous marsupial, the dibbler.

These species are all likely to face the same threats and may be equally affected by the changing climate. Future studies will attempt to model these species and to assess whether all will benefit from similar management.

Many challenges remain for the western ground parrot, including the possible negative genetic impacts of the current small population size, and the increasing risk of damaging fires in a drying and warming climate.

But locating “future-proofed” sites is giving us some hope we can ensure the long term persistence of this enigmatic species, and the myriad other unusual species that occur in the biodiversity hotspot of southwestern Australia.


The authors would like to thank Allan Burbidge and Sarah Comer from the WA Department of Biodiversity Conservation and Attractions for their invaluable help and guidance in putting together this article.The Conversation

Shaun Molloy, Associate research scientist (Ecology), Edith Cowan University and Robert Davis, Senior Lecturer in Vertebrate Biology, Edith Cowan University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Australia: Queensland – Hairy-Nosed Wombats


The link below is to an article reporting on how man-made burrows are helping Hairy-Nosed Wombats survive and breed.

For more visit:
http://www.australiangeographic.com.au/journal/designer-burrows-man-made-for-rare-wombat.htm

Antarctica: Emperor Penguins


The link below is to an article that considers Antarctica’s Emperor Penguins and how they survive the extreme cold.

For more visit:
http://blogs.smithsonianmag.com/science/2013/03/how-emperor-penguins-survive-antarcticas-subzero-cold/

Coral Reefs in the 21st Century – Can They Survive?


The link below is to the Australian ABC’s Future Forum and its look at the future of coral reefs (the link probably won’t be there for too long) in the face of climate change.

For more visit:
http://www.abc.net.au/news/abcnews24/programs/future-forum/

Malcolm Naden: Barrington Tops Warning for Travellers


Travellers to the Barrington Tops are being warned that outlaw and modern bushranger Malcolm Naden is suspected of hiding out in the remote wilderness area. There is currently a $50 000 reward for information that leads to his capture. He is the most wanted person in New South Wales, suspected of being involved in the disappearance of his cousin Lateesha Nolan and the murder of Kristy Scholes in 2005 at Dubbo.

Naden has sought refuge in the bush in the region bordered by Dubbo in the west and Kempsey in the east since 2005. During this time he has broken into homes, stealing non-perishable food items, camping gear and other equipment required to survive the bushland in which he hides and lives. He is known to be an expert bushman.

Naden first hid in the Western Plains Zoo at Dubbo and has since been known to have been in the vicinity of the Barrington Tops. In 2008 he was known to be in the vicinity of Stewarts Brook, in the western Barrington Tops area. In January 2009 he was known to be at Bellbrook, west of Kempsey. Three months ago he was known to be at Mount Mooney, in the northern Barrington Tops. It is thought that he is also responsible for similar break-ins around the Mount Mooney area in late August 2010. There have been a large number of break-ins across the region this year. He is believed to be armed, with a rifle having been stolen in one of the break-ins. Not all of the break-ins are confirmed as being committed by Malcolm Naden, but they all seem to bear his signature.

According to local newspapers, it is also believed that kangaroo carcasses have been found in the Barrington Tops, butchered in an expert manner. Naden was an abattoir worker and similar carcasses were found at the Dubbo zoo when Naden was hiding there.

The area in which Malcolm Naden is thought to be hiding was once the hideout for the bushranger known as ‘Captain Thunderbolt.’ Naden seems to be following in Thunderbolt’s footsteps in more ways than one.

For more on Malcolm Naden visit:

http://www.police.nsw.gov.au/can_you_help_us/wanted/malcolm_john_naden

http://coastmick21.blogspot.com/

http://www.smh.com.au/news/national/police-seek-man-on-run-after-cousin-found-dead/2005/08/21/1124562750384.html

http://www.australianmissingpersonsregister.com/Naden.htm

http://www.brisbanetimes.com.au/news/national/wanted-man-and-a-town-in-fear/2009/01/17/1232213416486.html

http://www.facebook.com/topic.php?uid=4884239637&topic=7725

http://www.theherald.com.au/news/local/news/general/danger-at-the-tops-break-ins-point-to-fugitive/1928579.aspx

http://www.smh.com.au/nsw/publics-help-sought-over-murder-cases-20100904-14v5u.html