Riparian

Review: Vegetation of Australian Riverine Landscapes

The Book – Vegetation of Australian Riverine Landscapes (Biology, Ecology and Management)
The Editors – Samantha Capon, Cassandra James, and Michael Reid

Riverine ecosystems are dynamic and diverse, and are strongly influenced by the flora that inhabit them. However, not only it is important to acknowledge how riverine plants influence their environment, but also to appreciate the processes that sustain our riverine vegetation. Vegetation of Australian Riverine Landscapes aims to encourage this appreciation, and to inspire interest in these fascinating landscapes.

Split into four sections, this book discusses the natural processes and anthropogenic impacts that affect the riverine vegetation of Australia, while also describing key taxa and the adaptations and life histories that allow them to exist in riverine habitats. The editors of this book hope that their text ‘fosters awareness of the incredible diversity and dynamic nature of riverine vegetation across Australia both for its own sake and for its vital functional role.’

The first section explores the spatial and temporal characteristics of riverine landscapes in Australia, and describes the diverse habitats determined by those characteristics. The history of our riverine vegetation is described, taking the reader on a journey from Australia’s most recent glacial period, through the Holocene, and into the present. This section also discusses the anthropogenic effects that alter our riverine habitats.

Section Two, named ‘Riverine plants’, discusses the key plant groups that are found in riverine habitats. Inconspicuous yet widespread, the bryophytes, aquatic algae, and charophytes are emphasised as functionally significant taxa in riverine environments. The diversity of vascular aquatic macrophytes and riparian herbs is discussed in this section, as is the ecology and life history characteristics that allow these taxa to survive in dynamic riverine environments. The larger, most noticeable species - the trees and shrubs - are also described in this section.

The third section in this book describes the riverine habitats of five major regions of the Australian continent, and how the vegetation varies depending on each region’s geographic location and climate. The floodplains and wetlands along the south-east coast of Australia are explored, including mangrove communities, coastal salt marshes, and brackish meadows. In contrast, the chapter devoted to inland south-eastern Australia describes the floristic characteristics of the Murray-Darling Basin as being dominated by woodland, forest and shrubland communities. The riparian vegetation of treeless high country is also discussed, as is the riparian vegetation of tropical northern Australia and the vegetation of desert river landscapes.

Finally, the authors describe the main management concerns regarding the riverine ecosystems of Australia. These include the consideration of various threats to our riverine landscapes, including water management, salinisation, fire, grazing and weeds. For example, while reviewing this book I learnt that at present there are over 3000 invasive plant species growing wild in Australia. These weeds account for 13% of Australia’s flora.  Luckily, restoration practices and monitoring techniques are also examined in this section.

Vegetation of Australian Riverine Landscapes lives true to its name, and provides an in-depth description of the plants and processes that are found in our Australian freshwater environments. Written in a succinct manner and with concise graphs and maps, this text will serve anyone interested in learning more about our riverine landscapes.

This book belongs on your bookshelf if… you're a student studying riverine ecosystems, you're interested in plants and how they adapt to their environment or if you're involved in land management.

Not as we know it: Along the Maribyrnong

This is a guest post by Mary Shuttleworth

Brimbank Park is only 15 kilometres out of Melbourne city, and yet, embarrassingly, I hadn’t bothered to make the trip up there until about two weeks ago. It’s full of a wonderful range of native plants and wildlife, and even though it’s quite close to the hugely developed Melbourne Airport, it feels like it’s hundreds of miles away. It’s a welcome escape from the residential areas I’ve become so accustomed to. Visiting parks like Brimbank always make me wistful. I’m struck by an awareness that once, everything would have looked like this - minus the picnic spots and water fountains, of course. The north-western suburbs of Melbourne have seen rapid increases in development in the last few years. From Yarraville to Footscray, and stretching out past Keilor, both residential and industrial developments have transformed the suburbs significantly in the last 50 years. It’s almost impossible to fathom the changes made to these areas over the last 300 years, before airports, roads, pavement or farmland.

Old Red Gums over the Maribyrnong. Image: Weekend Notes

Old Red Gums over the Maribyrnong. Image: Weekend Notes

Prior to European colonisation, Maribyrnong River and the surrounding areas were an expanse of trees, shrubs, and grassy plains. Up the northern area of the river, which now runs through Keilor and up alongside what we now know as Melbourne International Airport, the river was surrounded by fertile, rich scrubland. Narrow-leaf peppermint would have arched over the water, reaching up to 15 metres tall. Kidney-weed, hairy panic and wingless bluebush would have been common, most of the soil covered by these low-lying species, with only a few larger shrubs and medium-sized trees poking up between the competitive grasses. Away from the river, the trees died back, replaced by a sweeping grassland that occurred across Keilor and Tullamarine, stretching down as far as Essendon North. Grasses such as kangaroo grass, mat grass and kidney-weed would have swept across the area, providing vital habitats for native species, in particular invertebrates. Melbourne’s International Airport, now paved and developed into a hub of transport, was once an expanse of grassy plains, home to some of the 140 species of butterfly found in Victoria, such as the orchard swallowtail and grassland copper.

The Maribyrnong River today. Image: The Buckley

The Maribyrnong River today. Image: The Buckley

Closer to what we now call the suburb of Maribyrnong, the habitats surrounding the river shifted to riparian woodland. Here river red gum, manna gum and Gippsland red Gum towered up to 20 metres alongside the water, herbs and shrubs making up the understory as the river swept around bends.

Quickly, though, the salty waters of the Maribrynong River would have taken hold, and these great trees would have died back. Even today the river is flushed with salty water from coastal swells, though you wouldn’t realise it when you look at the lush grass along Flemington Racecourse. 300 years ago, these swells affected the habitats as well, sending salt through the soils surrounding the river. The only plants that prospered were ones that were adapted to the salty waters, predominantly low-lying species such as variable willow-herb, creeping brookweed, white sebaea, and Australian salt-grass. Almost no trees would have been found in these areas, the salty soils keeping them at bay. 

With all of this in mind, it is no surprise that the Maribyrnong River Trail is one of the most scenic in Melbourne. Scattered with parks and picnic areas, it meanders into Melbourne city much like the river itself, lazily looping around suburbs and landmarks. It is particularly popular on weekends, with dog-walkers, families, and fitness enthusiasts making their way along the pathway at their own pace. Though the surrounding areas of Maribyrnong, Footscray, Yarraville, Ascot Vale, Keilor, Flemington, and Kensington have seen much development in recent years, the winding nature of the river has helped shape these suburbs into what we see today.