Recreating the Country blog
Three talks and a conversation on climate change
The conference was held at Melbourne Conference and Exhibition centre on Thursday 22nd & Friday 23rd September. For those that had the time there were eleven field trips to choose from on Wednesday 21st. I headed off to Christmas Hills and Healesville for the day. The master of ceremonies for the conference was the very entertaining and down to earth host of Gardening Australia Costa Georgiadis
Talk 1 - Let’s start with the bad news
Dr Will Steffen from the Climate Council of Australia spoke bluntly and emphatically on climate change trends, stripping away the wishy washy rhetoric of conservative politicians with undisputable scientific observations and predictions like;
You can read more detail on https://www.climatecouncil.org.au/contributors/will-steffen
Surprisingly the professionalism and science behind Dr Steffen’s presentation gave me an unexpected feeling of hope which I can only explain by saying that if scientists of his calibre are working on solutions we may just get around to applying some of them, if the conservative politicians and the interests that they represent can just stop dragging their feet.
You could also look at this site for our national approach to climate change
Talk 2 - Now some good news;
There was an air of optimism when Dr. Siwan Lovett spoke passionately on the ‘Rivers of Carbon, Rivers of Life’ program that she has been involved in the Goulburn district in New South Wales. Challenging her audience she said,
“The greatest threat to our planet is the belief that someone else will fix it”
The story she told about a very successful program aimed at restoring vegetation on waterways clearly showed a way forward.
In a nutshell she was saying that the best place to start repairing waterway vegetation is on river bank sites that are in the best condition and therefore have the highest potential for recovery.
She would say to landholders about their waterways and wetlands,
“We are here to mess it up and slow it down”.
Neat rivers store very little carbon and are carbon poor. Messy waterways with trees, shrubs, grasses and fallen logs store a lot of carbon.
Carbon typically enters the waterways two ways. Litter from plants and animals is carried into rives and is buried in sediment, locking it up potentially for thousands of years. In the water carbon is stored by algae and aquatic plants that absorb it as they grow. Organic matter (carbon) in the waterways is eaten by microorganisms, insects and fish.
On river banks vegetation provides corridors through the landscape for both terrestrial and aquatic species increasing biodiversity, connectivity and stored carbon which is ideal for maximising both carbon sequestration and biodiversity conservation on a local and a regional scale.
In the Rivers of Carbon program equal value is given to needs of place and people, valuing equally landholder practical knowledge and scientific expertise. This combination underpins all works and inspires motivation through confidence in the predicted outcomes. If you would like to find out more about this very successful program click on this link
Talk 3 - Locking up carbon in the soil and reducing methane emissions from cattle was Kathy Dawson’s theme.
Carbon sequestration was achieved with an innovative program which involved the humble dung beetle and an ancient carbon rich soil enhancer used by the Mayans and Incas called biochar which is a charcoal product made from organic matter that is burnt slowly without oxygen. This process creates a fine-grained, highly porous charcoal that helps soils retain nutrients and water.
By feeding a beef herd a daily ration of biochar and introducing dung beetles, Bubas bison, the biochar was infused into the manure and incorporated into soil to depths of 60 cm. She spoke of pasture improvements of 30% and reduced emissions of rumen gasses.
Kathy is from Warren Catchments Council inc. in south west WA. To follow up on this idea please click on these links.
- with Kevin Chaplin, CMA officer from Mildura.
Sheoaks are in trouble in arid regions
Sheoaks are survivors and have adapted well to both the wet and dry conditions that Australia can offer, but a survival strategy that has got them through a gradually drying and warming climate and the many significant climate changes over the past 50 million years, appears to be unravelling.
Sheoaks are the ‘luddites’ of the plant world because the way they reproduce is as old fashioned and inefficient as commuting to work on horse-drawn cart would be today. They rely on wind to carry pollen from male plants to female plants which is a system that became old fashioned when insects started to do this job for plants over 50 million years ago.
At the time sheoaks were emerging some other iconic Australians, banksias and eucalypts, were also on the rise. These plants embraced the new insect reliant system which enabled them to share pollen over long distances. When insects do the pollinating plants genes can be shared over tens of kilometres, but when wind does this job it’s reliable over just a few hundred meters.
Two sheoaks that have made arid Australia their home are Belah, Casuarina cristata and Buloke, Allocasuarina luehmannii. Both are small trees growing to over 10 meters and both have adapted well to extremely dry climates.
Kevin gave me an insight into their plight that shocked me. He had observed that the current climatic shift to dryer winters and wetter summers was making the arid landscapes dryer overall. Because of the speed of this change in climate these dry climate specialists were not adapting fast enough and were dying.
Normally the resilient sheoaks would share pollen with others of the same species in dryer (or wetter) climates allowing future generations to adapt. This pollen sharing would happen over long distances in small wind driven steps through a network of sheoaks extending across the country. But this network has been broken in arid areas largely through clearing of land to enable the use of huge ‘centre pivot irrigation’ watering systems for broad acre cropping.
It is the endangered Red-tailed Black Cockatoos that is also the loser in this story as they depend on the seeds of the Buloke for food as well as old eucalypts that have very deep hollows for nesting.
Aside from looking for moister drainage lines to replant these sheoaks, composite provenancing can broaden the gene pool of isolated remnant patches. In brief this involves including 10 – 30% of seedlings from dryer districts (if they exist) in the revegetation mix as well as plants from nearby patches that would have shared pollen when the landscape was better connected.
For more on composite provenancing and variations to this solution you could read
Composite provenancing – progressing the ‘local is best’ paradigm for seed sourcing by Dr. Andrew Lowe.
Stephen Murphy is qualified in Geology and Environmental Management and has been a nurseryman and a designer of natural landscapes for over 30 years. He loves the bush, supports Landcare and is a volunteer helping to conserve local reserves.