Sonic booms and algal blooms: a smart approach to detoxifying waterways

A recent report here in New Zealand has raised some interesting issues around data interpretation and the need for independent analysis to minimise bias. The study has examined the state of our fresh water environment over the past decade, leading to the conclusion that our lakes and rivers are improving in water quality.

However, some of the data fails to support this: populations of freshwater macro invertebrates remain low, following a steady decline over many decades. Therefore while the overall tone of the report is one of optimism, some researchers have claimed that the data has been deliberately cherry-picked in order to present as positive a result as possible.

Of course, there are countless examples of interested parties skewing scientific data for their own ends, with government organisations and private corporations among the most common culprits. In this case, the recorded drop in nitrate levels has been promoted at the expense of the continued low population of small-scale fauna. You might well ask what use these worms, snails and insects are, but even a basic understanding of food webs shows that numerous native bird and freshwater fish species rely on these invertebrates for food. As I've mentioned so often the apparently insignificant may play a fundamental role in sustaining human agriculture (yes, some other species practice farming too!)

So what is it that is preventing the invertebrates' recovery? The answer seems to be an increase in photosynthetic cyanobacteria, or as is more commonly - and incorrectly known - blue-green algae. If it is identified at all, it's as a health food supplement called spirulina, available in smoothies and tablet form. However, most cyanobacteria species are not nearly as useful - or pleasant. To start with, their presence in water lowers the oxygen content, so thanks to fertiliser runoff - nitrogen and phosphorus in particular - they bloom exponentially wherever intensive farming occurs close to fresh water courses. Another agriculture-related issue is due to clearing the land for grazing: without trees to provide shade, rivers and streams grow warmer, encouraging algal growth. Therefore as global temperatures rise, climate change is having yet another negative effect on the environment.

Most species of cyanobacteria contain toxins that can severely affect animals much larger than fresh water snails. Dogs have been reported as dying in as little as a quarter of an hour from eating it, with New Zealand alone losing over one hundred and fifty pet canines in the past fifteen years; it's difficult to prevent consumption, since dogs seem to love the smell! Kiwis are no stranger to the phylum for other reasons, as over one hundred New Zealand rivers and lakes have been closed to swimmers since 2011 due to cyanobacterial contamination.

Exposure to contaminated water or eating fish from such an environment is enough to cause external irritation to humans and may even damage our internal organs and nervous system. Drinking water containing blue-green algae is even worse; considering their comparable size to some dogs, it is supposed that exposure could prove fatal to young children. Research conducted over the past few years also suggests that high-level contamination can lead to Lou Gehrig's disease, A.K.A. amyotrophic lateral sclerosis, the same condition that Stephen Hawking suffered from.

What research you might ask is being done to discover a solution to this unpleasant organism? Chemicals additives including copper sulphate and calcium hypochlorite have been tried, but many are highly expensive while the toxicity of others is such that fish and crustacean populations also suffer, so this is hardly a suitable answer.

A more elegant solution has been under trial for the past two years, namely the use of ultrasound to sink the blue-green algae too deep to effectively photosynthesise, thus slowly killing it. A joint programme between New Zealand and the Netherlands uses a high-tech approach to identifying and destroying ninety per cent of each bloom. Whereas previous ultrasonic methods tended to be too powerful, thereby releasing algal toxins into the water, the new technique directly targets the individual algal species. Six tests per hour are used to assess water quality and detect the species to be eradicated. Once identified, the sonic blasts are calibrated for the target species and water condition, leading to a slower death for the blue-green algae that avoids cell wall rupture and so prevents the toxins from escaping.

Back to the earlier comment as to why the report's conclusions appear to have placed a positive spin that is unwarranted, the current and previous New Zealand Governments have announced initiatives to clean up our environment and so live up to the tourist slogan of '100% Pure'. The latest scheme requires making ninety percent of the nation's fresh water environments swimmable by 2040, which seems to be something of a tall order without radical changes to agriculture and the heavily polluting dairy sector in particular. Therefore the use of finely target sonic blasting couldn't come a moment too soon.

Our greed and short-sightedness has allowed cyanobacteria to greatly increase at the expense of the freshwater ecosystem, not to mention domesticated animals. Now advanced but small-scale technology has been developed to reduce it to non-toxic levels, but is yet to be implemented beyond the trial stage. Hopefully this eradication method will become widespread in the near future, a small victory in our enormous fight to right the wrongs of over-exploitation of the environment. But as with DDT, CFCs and numerous others, it does make me wonder how many more man-made time bombs could be ticking out there...

The anaesthetic of familiarity: how our upbringing can blind us to the obvious

In the restored Edwardian school classroom at Auckland's Museum of Transport and Technology (MOTAT) there is a notice on the wall stating 'Do not ask your teacher questions.' Fortunately, education now goes some way in many nations to emphasising the importance of individual curiosity rather than mere obedience to authority. Of course, there are a fair number of politicians and corporation executives who wish it wasn't so, as an incurious mind is easier to sway than a questioning one. As my last post mentioned, the World Wide Web can be something of an ally for them, since the 'winner takes all' approach of a review-based system aids the slogans and rhetoric of those who wish to control who we vote for and what we buy.

Even the most liberal of nations and cultures face self-imposed hurdles centered round which is the best solution and which is just the most familiar one from our formative years. This post therefore looks at another side of the subjective thinking discussed earlier this month, namely a trap that Richard Dawkins has described as the "anaesthetic of familiarity". Basically, this is when conventions are so accepted as to be seen as the primary option instead of being merely one of a series of choices. Or, as the British philosopher Susan Stebbing wrote in her 1939 book Thinking to Some Purpose: "One of the gravest difficulties encountered at the outset of the attempt to think effectively consists in the difficulty of recognizing what we know as distinguished from what we do not know but merely take for granted."

Again, this mind set is much loved by the manufacturing sector; in addition to such well-known ploys as deliberate obsolescence and staggered release cycles, there are worse examples, especially in everyday consumerism. We often hear how little nutritional value many highly processed foods contain, but think what this has done for the vitamin and mineral supplement industry, whose annual worldwide sales now approach US$40 billion!

Citizens of developed nations today face very different key issues to our pre-industrial ancestors, not the least among them being a constant barrage of decision making. Thanks to the enormous variety of choices available concerning almost every aspect of our daily lives, we have to consider everything from what we wear to what we eat. The deluge of predominantly useless information that we receive in the era of the hashtag makes it more difficult for us to concentrate on problem solving, meaning that the easiest way out is just to follow the crowd.

Richard Dawkins' solution to these issues is to imagine yourself as an alien visitor and then observe the world as a curious outsider. This seems to me to be beyond the reach of many, for whom daily routine appears to be their only way to cope. If this sounds harsh, it comes from personal experience; I've met plenty of people who actively seek an ostrich-like head-in-the-sand approach to life to avoid the trials and tribulations - as well as the wonders - of this rapidly-changing world.

Instead, I would suggest an easier option when it comes to some areas of STEM research: ensure that a fair proportion of researchers and other thought leaders are adult migrants from other nations. Then they will be able to apply an outside perspective, hopefully identifying givens that are too obvious to be spotted by those who have grown up with them.

New Zealand is a good example of this, with arguably its two best known science communicators having been born overseas: Siouxsie Wiles and Michelle Dickinson, A.K.A. Nanogirl. Dr Wiles is a UK-trained microbiologist at the University of Auckland. She frequently appears on Radio New Zealand as well as undertaking television and social media work to promote science in general, as well as for her specialism of fighting bacterial infection.

Dr Dickinson is a materials engineering lecturer and nanomaterials researcher at the University of Auckland who studied in both the UK and USA. Her public outreach work includes books, school tours and both broadcast and social media. She has enough sci-comm kudos that last year, despite not having a background in astronomy, she interviewed Professor Neil deGrasse Tyson during the Auckland leg of his A Cosmic Perspective tour.

The work of the above examples is proof that newcomers can recognise a critical need compared to their home grown equivalents. What is interesting is that despite coming from English-speaking backgrounds - and therefore with limited cultural disparity to their adoptive New Zealand - there must have been enough that was different to convince Doctors Wiles and Dickinson of the need for a hands-on, media savvy approach to science communication.

This is still far from the norm: many STEM professionals believe there is little point to promoting their work to the public except via print-based publications. Indeed, some famous science communicators such as Carl Sagan and Stephen Jay Gould were widely criticised during their lifetime by the scientific establishment for what were deemed undue efforts at self-promotion and the associated debasement of science by combining it with show business.

As an aside, I have to say that as brilliant as some volumes of popular science are, they do tend to preach to the converted; how many non-science fans are likely to pick up a book on say string theory, just for a bit of light reading or self-improvement (the latter being a Victorian convention that appears to have largely fallen from favour)? Instead, the outreach work of the expat examples above is aimed at the widest possible audience without over-simplification or distortion of the principles being communicated.

This approach may not solve all issues about how to think outside the box - scientists may be so embedded within their culture as to not realise that there is a box - but surely by stepping outside the comfort zone we grew up in we may find problems that the local population hasn't noticed?

Critical thinking is key to the scientific enterprise, but it would appear, to little else in human cultures. If we can find methods to avoid the anaesthetic of familiarity and acknowledge that what we deem of as normal can be far from optimal, then these should be promoted with all gusto. If the post-modern creed is that all world views are equally valid and science is just another form of culture-biased story-telling, then now more than ever we need cognitive tools to break through the subjective barriers. If more STEM professionals are able to cross borders and work in unfamiliar locations, isn’t there a chance they can recognise issues that fall under the local radar and so supply a new perspective we need if we are to fulfil our potential?