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the end of phosphates - we hope

I actually read this article yesterday, but I’ve been completely swamped at work and otherwise busy with a report on dryland salinity when I get home (seriously.  It’s more interesting than you’d think).

Anyway, while I’m certainly no fan of the large supermarket chains, this struck me as really positive news - if running very, very late.  See, phosphates play a really nasty role in the eutrophication of waterways - in a very-unscientific-nutshell, this means;

1) Cyanobacterial algal blooms (that’s the bad sort of algae - the manky blue-green crap they show on science documentaries)

2) Suffocating fish.  This is usually due to the algal blooms, which block sunlight to underwater plants, stalling their usual process of photosynthesis, which is imperative to the underwater oxygen supply.  Less/ no oxygen= less/ dead fish.

3) General ecosystem toxicity.  Cyanobacterial blooms are incredibly toxic to livestock and to shellfish (and the humans who eat them)

And this is just the most basic summary I could throw together in a lunchbreak. So, why has it taken so long for major companies to start even phasing out the use of phosphates? Why hasn’t this been a government requirement, not something subject to the “good will” of major players such as Coles, Woolworths and Unilever (read: public pressure)?

Good question.  The EU first raised the issue and began initiating a ban on phosphates back in 2005.  In December 2010, it was determined that they would be outright illegal in all laundry detergents from 1 January 2013 (why this takes 8 years to fully implement is beyond me - I know that they need to warn producers and suppliers, but 8 years seems a tad excessive).  In the US, a number of states placed restrictions on phosphates and there was a voluntary industry-wide ban in 1993.  And in Australia?  There’s never been a change until now.  I don’t know the reasons, but I’m glad that finally, something is happening.

In the meantime though, check your detergents.  There are already quite a few phosphate-free alternatives out there - and they’re all pretty happy to advertise that fact.

Algal blooms threaten NW salmon

news.opb.org

A cousin of the algae that causes paralytic shellfish poisoning causes trouble for salmon.

Towards the bottom of the marine food chain you’ll find Heterosigma Akashiwo. They’re among the smallest creatures in the ocean. And most of the time, they’re harmless. But every year, in the spring and fall, these microscopic phytoplankton join forces and become the terror of the sea.

Algae invades Chinese beach

Green algal blooms aren’t dangerous to humans - although the same can’t be said for red tides, which are caused by another algae species and can create harmful toxin. The Chinese people obviously didn’t care. 

Record-setting algal bloom in Lake Erie caused by agricultural and meteorological trends consistent with expected future conditions

Michalak, A.M., E.J. Anderson, D. Beletsky, S. Boland, N.S. Bosch, T.B. Bridgeman, J.D. Chaffin, K. Cho, R. Confesor, I. Daloğlu, J.V. DePinto, M.A. Evans, G.L. Fahnenstiel, L. He, J.C. Ho, L. Jenkins, T.H. Johengen, K.C. Kuo, E. LaPorte, X. Liu, M.R. McWilliams, M.R. Moore, D.J. Posselt, R.P. Richards, D. Scavia, A.L. Steiner, E. Verhamme, D.M. Wright, and M.A. Zagorski, 2013: “Record-setting algal bloom in Lake Erie caused by agricultural and meteorological trends consistent with expected future conditions.” Proceedings of the National Academy of Sciences, doi: 10.1073/pnas.1216006110.

In 2011, Lake Erie experienced the largest harmful algal bloom in its recorded history, with a peak intensity over three times greater than any previously observed bloom. Here we show that long-term trends in agricultural practices are consistent with increasing phosphorus loading to the western basin of the lake, and that these trends, coupled with meteorological conditions in spring 2011, produced record-breaking nutrient loads. An extended period of weak lake circulation then led to abnormally long residence times that incubated the bloom, and warm and quiescent conditions after bloom onset allowed algae to remain near the top of the water column and prevented flushing of nutrients from the system. We further find that all of these factors are consistent with expected future conditions. If a scientifically guided management plan to mitigate these impacts is not implemented, we can therefore expect this bloom to be a harbinger of future blooms in Lake Erie.

Open Access

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