[Music plays and text appears: Australia’s biodiversity – Inland waters]
[Image changes to show Dr. Carmel Pollino – Ecologist]
Dr. Carmel Pollino: So within Australia we have a diversity of inland water ecosystems, rivers, so riverine kind of ecosystems.
[Image changes to various images of rivers and streams]
And even within rivers we have different types of rivers, we have perennial rivers, so permanent rivers, and then we have more ephemeral kind of streams, and so they also support different types of ecosystems.
[Images changes to various images of wetlands]
From there we have wetlands as well, so we have wetlands that often sit at the bottom of river systems, but also wetlands that sit through an actual catchment as well.
[Image changes to various images of floodplains]
And we have a range of floodplains and floodplain ecosystems, and so when you have a river that floods it supports a whole lot of water dependent ecosystems along the breadth of its floodplain.
[Image changes to ducks floating on the water]
[Image has changed back to Dr. Carmel Pollino]
We also have groundwater ecosystems, and they’re probably one of our least studied type of ecosystems, and so they sit – we obviously can’t see them there in the groundwater, but they’re very isolated systems and support a very unique biodiversity.
[Image changes to a satellite picture of Lake Eyre and text appears: Kati Thanda – Lake Eyre]
And we have many unique ecosystems that are supported through Australia, and one of them, the largest kind of iconic ecosystem is Lake Eyre Basin.
[Image changes to a map of Lake Eyre]
[Image changes to aerial footage of Lake Eyre]
[Image has changed back to Dr. Carmel Pollino]
So it’s an inland draining basin, it’s very much one of those iconic basins in terms of being a boom and a bust. So when Lake Eyre floods it’s a big... it’s a big flood event, you often have a boom in terms of fish productivity, a boom in terms of the number of waterbirds that move to the Lake Eyre Basin.
[Images changes to Lake Eyre in flood]
[Images changes to bird flying over Lake Eyre]
[Image changes to an open field]
[Image has changed back to Dr. Carmel Pollino]
And then after that period of the boom you have a drying, a bust kind of period is what we call it, and so during the bust period you have the drying up to kind of remnant creek areas, and it’s those remnant areas that are really important for supporting your fish, and it’s about supporting those fish through the dryer times, through the bust times, to be able to get to that next boom.
[Image changes to a sunset and text appears: Human impacts on inland water ecosystems]
[Image has changed back to Dr. Carmel Pollino]
So humans have had a dramatic influence on our inland water ecosystems and that extends back many years.
[Image changes to a creek and text appears: Brewarrina Aboriginal fish traps – Baiame’s ngunnhu]
[Image changes to a picture of a rock culvert in the river]
An example of that is the Brewarrina fish traps which are believed to be about 40,000 years old, and what they are is a series of rock culverts through a river system, and they were used by the Indigenous people to trap fish, and obviously eat those fish.
[Image has changed back to Dr. Carmel Pollino]
[Image changes to various pictures of dams]
Since the early 20th Century we’ve seen a large expanse in terms of water resource development in Australia, and that has been particularly in the south east part of Australia.
[Image changes to an irrigation system and text appears: Irrigated agriculture]
[Image changes to water coming out of a pipe on the ground]
[Image changes to various pictures of farmland crops]
So irrigated agriculture is very important in terms of it provides us with food, irrigated agriculture in the Murray-Darling Basin provides a great proportion of our agriculture in terms of people being able to use the food that comes from that particular basin.
[Image has changed back to Dr. Carmel Pollino]
And so the challenge that we have is how do we start sustainably have our agricultural systems and meet the diversity of values that we have, particularly in the Murray-Darling Basin.
[Image changes to a boat speeding along on a river]
[Image changes to bird flying]
[Image changes to view from a plane flying above the ground]
So ensuring that we have a healthy working river, a healthy river in terms of its ecologically able to function, and also be able to support communities, and irrigation communities that are now reliant on the water resources within the basin.
[Image has changed back to Dr. Carmel Pollino]
[Image changes to various pictures of floodplains and text appears: Changing flood cycles are changing biodiversity]
So what we’ve seen in terms of water resource development through many parts of Australia, and certainly through the south eastern parts of Australia, is that it’s actually the changes in the flooding cycles that are starting to affect our ecology on those floodplains, so our floodplains are retracting, they’re getting smaller in terms of their size, and associated with that you have a change in your biodiversity and your flora and your fauna.
[Image changes to a man holding a fish]
[Images changes to a sunset and text appears: Ecosystem restoration]
[Image has changed back to Dr. Carmel Pollino]
It’s through restoration activities that we start to try and improve our wetlands and restore the impacts that we’ve seen through irrigation.
[Image changes to a floodplain]
[Image changes to farmland and sheep grazing]
[Image changes to an irrigation system]
[Image has changed back to Dr. Carmel Pollino]
And an example of that is looking at the Paika Lake wetland system, and that’s in the Murrumbidgee, it’s down in the Lowbidgee part of the catchment, so the lower part of the catchment.
[Image changes to a wetland]
[Image has changed back to Dr. Carmel Pollino]
And the Paika Lake system was isolated from the river system for about a hundred years, and so through development of irrigation infrastructure, as well as just development of roads, you saw no connection of water through to the Paika Lake ecosystem.
[Image changes to swampland and text appears: Cherax Swamp restoration]
[Image changes to varying stages of swampland flash past on the screen]
[Image changes to birds on the water]
And so what has happened in the last few years is environmental flows have started to be delivered to that ecosystem and it’s a restoration activity that’s been undertaken, and what has been observed is a great boom in terms of you had a lot of birds move into the area, we’ve seen fish move into the area, aquatic plants emerge from the soils, and it’s a very nice little case study where we can start to see how best to restore our ecosystems after such a long period of dry.
[Image changes to varying stages of swampland flash past on the screen]
[Image has changed back to Dr. Carmel Pollino]
So with the challenges of climate change and water resource development there’s a real need for the science.
[Image changes to equipment being lowered into water from a boat and text appears: The role of science]
[Image changes to a man recording data in a wetland]
And that science to inform how we can protect our inland waters and our biodiversity within our inland waters, but also how to also cater for the various uses of water within our ecosystems, so we can do that equitably across our users of the water.
[Image has changed back to Dr. Carmel Pollino]
[Image changes to a wetland and text appears: MUSIC – Premiumbeat.com; ADDITIONAL IMAGES – John Coppi, NASA Goddard Space Flight Centre, Jennifer Firn, Brad Moggridge, Gregory Heath, Lucy Garner, Heather McGinness, Brad Shermane Canada, NOAA Pacific Ring of Fire 2004 Expedition. Creative Commons images (Flickr): NASA Earth Observatory, Department of Environment & Primary Industries (Vic), nic_pepsi, edenink, iain.davidson100, Luke Bailey, spelio]
[Music plays and CSIRO logo appears with text: Big ideas start here www.csiro.au]
