Monday, 26 September 2016

Mopping up spilt milk: pollution in the New Zealand dairy sector

It's been slow to dawn on New Zealanders, but for a country that prides itself on a '100% Pure' image our environmental pollution record is fairly appalling - and shows few signs of alleviation. Politicians who point to the large percentage of the nation's electricity generation coming from renewable sources, not to mention the slow but sturdy growth in hybrid vehicles, are completely missing the point: it has been claimed that over half of New Zealand's greenhouse gas emissions emanate from agri business.

Although the quantity of sheep in the country has plummeted from a 1982 peak of around 70 million to less than 30 million last year, cattle numbers continue to rise. There are about 3.6 million livestock on beef farms and circa 6.5 million dairy cattle. The latter sector generates twenty percent of New Zealand's exports and seven percent of its GDP, so it forms a substantial component of the kiwi economy. But with plans to double the country's dairy production by 2025, the term 'sustainable development' appears to be, well, unsustainable.

Since cattle create as much waste product as fourteen humans, it's not difficult to imagine some of the more obvious forms of dairy pollutant, smell and all. As New Zealand dung beetles are primarily forest dwellers there have been trials of introduced dung beetle species to help clean up the waste, with a reduction in nitrous oxide emissions from the soil and a lowering of cattle disease as side benefits. However, pastoral poo is only one element in the catalogue of pollutants caused by dairy farming.

Last summer I was taken to an outdoor swimming hole not far from Wanganui, consisting of a rectangular concrete-lined pool situated on the edge of a forest. I was informed that children had swam there until a decade or so, but no more: several signs warned that the water is contaminated and no longer safe for humans. This story has been repeated throughout New Zealand, with agriculture being by far the most common culprit. It isn't just artificial environments that have this problem; reports suggest that within the past twenty years about two-thirds of monitored swimming areas within rivers have become too polluted. And that's just for people; there's far less concern for the effects on river fauna and flora.

Although environmentalists have been issuing warnings for years, not enough has been done to alleviate this problem. Last month approximately five thousand inhabitants of Havelock North were taken ill due to tap water contaminated by campylobacter. The source was a series of bores which the director of the Infectious Diseases Research Centre at Massey University, Professor Nigel French, put down to pollution from sheep and cattle. Sources of contamination could include carcases of dead livestock, as well as faecal matter getting into waterways that provide the source of unchlorinated - and therefore at risk - tap water.

In fact, the outbreak appears to be the tip of the iceberg. Despite some hundreds of cases of illegal effluent discharge brought against New Zealand farmers each year, many more escape prosecution. It has to be said this seems to be a regular occurrence for the Ministry for Primary Industries, judging by the recent reports of their waiving prosecutions for commercial fishing vessels caught flouting bycatch and dumping laws. Turning a blind eye seems to be the order of the day when it comes to protecting food production - or at least the food producers. This philosophy seems to be driven by those who clearly have little understanding of the complexity - and at times fragility - of food webs. Not so much short-term thinking as profound myopia!

In addition to the organic matter there are chemical pollutants that can find their way into water supplies situated close to farms. Since the 1990s, the New Zealand Ministry for the Environment has been monitoring ground water for nitrates and has found levels substantially above those recommended for drinking water. Although chemical fertiliser has been blamed in addition to livestock effluent, environmental mapping suggests the latter is the primary cause, since the polluted areas heavily coincide with the widest-scale dairy production.

As well as polluting waterways dairy farmers have also been caught stealing billions of litres of water each year from rivers and aquifers, especially in the Canterbury region. Whilst not a form of pollution per se, this is obviously somewhat lacking in the environmentally-friendly stakes. The deforestation of low-lying plains for cattle grazing is also a source of pollution, as the lack of tree roots, besides allowing greater flooding, can generate increased run-off into rivers. This polluted water can lead to algal blooms, lowering oxygen levels and so endangering freshwater fish. That might not sound of any great concern except to diehard anglers, but for any whitebait fans, four of the five Galaxiidae species whose young form this delicacy are now said to be threatened.

The systematic destruction of forests to make way for pastoral land use has been repeatedly raised as a concern not just by environmental organisations but by the New Zealand Ministry of Agriculture and Forestry (MAF) itself. Their 2006 report claimed close to half a million hectares of the nation's forests were at risk of conversion to land for cattle grazing.

In addition, overseas forests are also affected: since 2008 the amount of palm kernels imported into New Zealand as a dairy cattle feed supplement has doubled to over 2 million tons per annum. This accounts for about twenty-five percent of global production and comes at the expense of destruction of rainforests in nations including Indonesia and Malaysia. Although the state-owned farm company Landcorp Farming Ltd is in the process of moving to a different supplement over the next year or so, the dairy giant Fonterra has not announced similar intentions. What's wrong with those guys: a surfeit of Milton Friedman in their formative years?

Having covered solids and liquids, it's time to move on to gas. As I've mentioned on various occasions, methane is a primary greenhouse gas. It was therefore shocking to discover that per capita, New Zealand has the greatest annual methane emission rate worldwide, accounting for over forty percent of the country's greenhouse gas emanations. The methane emission from dairy cattle alone has continually increased over the past quarter century, although the amount reported varies from ten percent to a whopping fifty percent or so. Perhaps that's not surprising, considering cattle can each generate up to 500 litres of methane per day!

There is some recent cause for hope, with various trials under way to reduce bovine emissions. These range from vaccination to selective breeding to diets bases on forage rape, with the latter showing that the change in feed affects fermentation - and therefore reduces methane production - in sheep. However, it wouldn't hurt to see the Government funding more research in this matter: one widely-reported paper last year was Massey University's The New Zealand Dairy Farming: Milking Our Environment for All its Worth, which received much criticism from the dairy sector when it was revealed to consist primarily of a student thesis.

It's very easy to become depressed with such deleterious effects coming from just one sector. Of course no nation can afford to rest on its laurels: we cannot turn the clock back. The halcyon image of bucolic ruralism is a myth perpetrated by those who have never worked on the land and farmers deserve the benefits of modern technology in their work as much as anyone. The development of sophisticated tools and software can aid the dairy sector in preserving the environment. as long as there is enough public money to support this eco-friendly research. But Government funding for this type of sustainable development appears to be sadly lacking. Doesn't it make sense that those who run God's Own Country should try a little harder to prove that the 100% Pure tagline isn't just marketing spin?

Friday, 26 August 2016

The benefit of hindsight: the truth behind several infamous science quotes

With utmost apologies to Jane Austen fans, it is a truth universally acknowledged that most people misinterpret science as an ever-expanding corpus of knowledge rather than as a collection of methods for investigating natural phenomena. A simplistic view for those who adhere to the former misapprehension might include questioning science as a whole when high-profile practitioners make an authoritative statement that is proven - in a scientific sense - to be incorrect.

Amongst the more obvious examples of this are the numerous citations from prominent STEM (Science, Technology, Engineering and Mathematics) professionals that are inaccurate to such an extreme as to appear farcical in light of later evidence. I have already discussed the rather vague of art of scientific prognostication in several connected posts but now want to directly examine several quotations concerning applied science. Whereas many quotes are probably as deserving of contempt as the popular opinion of them, I believe the following require careful reading and knowledge of their context in which to attempt any meaningful judgement.

Unlike Hollywood, STEM subjects are frequently too complex for simple black versus white analysis. Of course there have been rather derisible opinions espoused by senior scientists, many of which - luckily - remain largely unknown to the wider public. The British cosmologist and astronomer Sir Fred Hoyle has a large number of these just to himself, from continued support for the Steady State theory long after the detection of cosmic microwave background radiation, to the even less defensible claims that the Natural History Museum's archaeopteryx fossil is a fake and that flu germs are really alien microbes!

Anyhow, here's the first quote:

1) Something is seriously wrong with space travel.

Richard van der Riet Woolley was the British Astronomer Royal at the dawn of the Space Age. His most infamous quote is the archetypal instance of Arthur C. Clarke's First Law:  "When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong."

Although a prominent astronomer, van der Riet Woolley had little knowledge of the practical mechanics that would be required for spaceflight. By the mid-1930s the British Interplanetary Society had developed detailed (although largely paper-only) studies into a crewed lunar landing mission. In 1936 Van der Riet Woolley publically criticised such work, stating that the development of even an unmanned rocket would present fundamental technical difficulties. Bear in mind that this was only six years before the first V2 rocket, which was capable of reaching an altitude of just over 200km!

In 1956, only one year before Sputnik 1 - and thirteen years prior to Apollo 11 - the astronomer went on to claim that near-future space travel was unlikely and a manned lunar landing "utter bilge, really". Of course this has been used as ammunition against him ever since, but the quote deserves some investigation. Van der Riet Woolley goes on to reveal that his primary objection appears to have changed (presumably post-V2 and its successors) from an engineering problem to an economic one, stating that it would cost as much as a "major war" to land on the moon.

This substantially changes the flavour of his quote, since it is after all reasonably accurate. In 2010 dollars, Project Apollo has an estimated budget of about US$109 billion - incidentally about 11% of the cost of the contemporary Vietnam War. In addition, we should bear in mind that a significant amount of the contractors' work on the project is said to have consisted of unpaid overtime. Is it perhaps time to reappraise the stargazer from a reactionary curmudgeon to an economic realist?

Indeed, had Apollo been initiated in a subsequent decade, there is reasonable evidence to suggest it would have failed to leave the ground, so to speak. The uncertainty of the post-Vietnam and Watergate period, followed by the collapse of the Soviet Union, suggest America's loss of faith in technocracy would have effectively cut Apollo off in its prime. After all, another colossal American science and engineering project, the $12 billion particle accelerator the Superconducting Super Collider, was cancelled in 1993 after being deemed unaffordable. Yet up to that point only about one-sixth of its estimated budget had been spent.

In addition, van der Riet Woolley was not alone among STEM professionals: for three decades from the mid-1920s the inventor of the vacuum tube Lee De Forest is said to have claimed that space travel was impractical. Clearly, the Astronomer Royal was not an isolated voice in the wilderness but part of a large consensus opposed to the dreamers in the British Interplanetary Society and their ilk. Perhaps we should allow him his pragmatism, even if it appears a polar opposite to one of Einstein's great aphorisms: "The most beautiful thing we can experience is the mysterious. It is the source of all true art and science. .."

Talking of whom…

2) Letting the genie out of the bottle.

In late 1934 an American newspaper carried this quotation from Albert Einstein: "There is not the slightest indication that (nuclear energy) will ever be obtainable. It would mean that the atom would have to be shattered at will." This seems to be rather amusing, considering the development of the first self-sustaining nuclear chain reaction only eight years later. But Einstein was first and foremost a theorist, a master of the thought experiment, his father's work in electrical engineering not being noticeably sustained in his son. There is obviously a vast world of difference between imagining riding a beam of light to the practical difficulties in assembling brand new technologies with little in the way of precedent. So why did Einstein make such a definitive prediction?

I think it is possible that it may also have been wishful thinking on Einstein's part; as a pacifist he would have dreaded the development of a new super weapon. As the formulator of the equivalence between mass and energy, he could have felt in some way responsible for initiating the avalanche that eventually led to Hiroshima and Nagasaki. Yet there is no clear path between E=mc2 and a man-made chain reaction; it took a team of brilliant experimental physicists and engineers in addition to theorists to achieve a practical solution, via the immense budget of $26 billion (in 2016 dollars).

It is hardly as if the good professor was alone in his views either, as senior officials also doubted the ability to harness atomic fission for power or weaponry. In 1945 when the Manhattan Project was nearing culmination, the highest-ranking member of the American military, Fleet Admiral William Leahy, apparently informed President Truman that the atomic bomb wouldn't work. Perhaps this isn't as obtuse as it sounds, since due to the level of security only a very small percentage of the personnel working on the project knew any of the details.

Leahy clearly knew exactly what the intended outcome was, but even as "an expert in explosives" had no understanding of the complexity of engineering involved. An interesting associated fact is that despite being a military man, the Admiral considered the atomic bomb unethical for its obvious potential as an indiscriminate killer of civilians. Weapons of mass destruction lack any of the valour or bravado of traditional 'heroic' warfare.  Is it possible that this martial leader wanted the bomb to fail for moral reasons, a case of heart over mind? In which case, is this a rare example in which the pacifism of the most well-known scientist was in total agreement with a military figurehead?

Another potential cause is the paradigm shift that harnessing the power of the atom required. In the decade prior to the Manhattan Project, New Zealand physicist Ernest Rutherford had referred to the possibility of man-made atomic energy as "moonshine" whilst another Nobel laureate, American physicist Robert Millikan, had made similar sentiments in the 1920s. And this from men who were pioneers in understanding the structure of the atom!

As science communicator James Burke vividly described in his 1985 television series The Day the Universe Changed, major scientific developments often require substantial reappraisals in outlook, seeing beyond what is taken for granted. The cutting edge of physics is often described as being ruled by theorists in their twenties; eager young turks who are more prepared to ignore precedents. When he became a pillar of the establishment, Einstein ruefully commented: "To punish me for my contempt for authority, fate made me an authority myself."

Perhaps then, such fundamental shifts in technology as the development of space travel and nuclear fission require equally revolutionary changes in mind set and we shouldn't judge the authors of our example quotes too harshly. Then again, if you are an optimist, Clarke's First Law might seem applicable in this situation, in which case quotes from authority figures with some knowledge of the subject in hand should take note of the ingenuity of our species. If there is a moral to this to story, it is other than the speed of light in a vacuum and the Second Law of Thermodynamics, never say never...