The impact of bushfires on drinking water, rivers and fish
 Our drinking water, rivers and fish will all feel the impact of bushfires, experts warn, ABC Science, By Jo Khan, 9 Jan 2020,
When it rains after bushfires, the consequences stretch way beyond temporary relief for those on the front line — and scientists are warning of potentially dire impacts on our waterways.
They say the aftermath of the current fires could bring devastation to freshwater animals and plants, as well as drinking water catchments. This is because, while it may or may not help firefighters themselves, rain inevitably washes the ash and eroded soil from burnt forests into rivers and streams, shifting the bushfire impact to our crucial freshwater ecosystems. Waterways can also suffer immediately in a fire just from the temperature increase, according to Ross Thompson from the University of Canberra. “In one of the streams we worked on in Victoria, the Black Saturday fire got so hot that the stream boiled,” Professor Thompson said. Even if water doesn’t boil (which effectively sterilises it), many animals can’t withstand the sudden increase in temperature, and die. But it’s the longer term effects that have scientists really worried. Rain washes ash into waterwaysRain events after bushfires can transfer huge amounts of ash, burnt material, soil and dead animals into our rivers and lakes. There will be an increase in nutrients because there’s lots of phosphorous and nitrogen in ash,” said Professor Thompson, a freshwater ecologist who has studied water catchments after the 2003 fires in the ACT and the 2009 Black Saturday fires in Victoria. “You also see more sediment because trees are falling down and the river banks are getting knocked around.” As the water fills up with fine sediment and foreign, nutrient-rich material, the water quality can drop very quickly — and stay that way for a long time. “We’re still seeing higher sediment loads coming out of the Cotter River catchment and those fires were more than a decade ago,” Professor Thompson said. Freshwater animals lose oxygenAs soon as a fire has passed and the ash settles on rivers and lakes, bacteria in the water will start consuming the carbon in that ash. In the process of breaking down the carbon, the bacteria will also consume the dissolved oxygen in the water. The more carbon, the more oxygen will be taken out of the system. And most animals and plants can’t survive in such a low-oxygen environment, as was seen in the Murray Darling Basin last summer. “The the risk is we will see big fish kill events even in some of the larger rivers,” Professor Thompson said. “Even if the fires didn’t burn immediately adjacent to the river.” Changes in the turbidity, or amount of sediment in the water, is another factor that can threaten aquatic species. “We see a loss of a lot of invertebrates that rely on really stony streams, because the sediment and ash smothers the rocks and it changes the habitat.” Rescuing fish from ‘water like licorice’………..Drinking water quality affectedChanges to the insects and other invertebrates in an ecosystem, along with the influx of nutrients from the ash, can result in the growth of cyanobacteria — commonly known as blue-green algae (but it’s not actually algae). Cyanobacteria produce chemicals which may cause a range of water quality problems, starting with poor taste and odour, according to Stuart Khan, an urban water management expert at the University of New South Wales………. “Of more concern is that cyanobacteria can produce chemicals that are really quite toxic,” Professor Khan said. https://www.abc.net.au/news/science/2020-01-09/freshwater-ecosystems-water-catchment-bushfire-impact/11850826?pfmredir=ms |
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1.This month.
The Road to War brings a sharp focus to why it is not in Australia’s best interest to be dragged into a war with China which will almost inevitably go nuclear very quickly. The filmmaker has interviewed some of Australia’s senior foreign policy analysts who have vast experience behind them in analysing what really is going on here as the United States rattles its sabres with China. And sets us up to be its proxy, like the poor Ukranians have been fed into the Meatgrinder. So America can remain the Top Dog. The Road to War reveals how the United States through its spy base at Pine Gap and by stationing six nuclear capable B52 bombers in the Top End (without permission from the traditional owners) is making Australia a prime nuclear target if the current war of words suddenly melts down into full scale war.
The Road to War shows the implicit connection between Carbon emissions (the US military uses a whopping 70% of America’s annual petroleum to move its armies and vast War Machine around the globe to its 800+ military bases..but under a loophole wangled at Kyoto, the US military does not have to report its C02 annual emissions). The Road to War starts screening at selected cities and regional centres in March. See the trailer end for details.
Antinuclear 
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