Soil Science Journal Club : rant

Astonishing reasoning on Greenland from U.S. scientists

Andrew.Rate — Mon, 22 Jun 2009 05:47:00 GMT

The good news (for some of the approximately 57,600 Greenlanders, at least): Greenland now has much more control over its destiny, following the decision from Denmark to allow self-rule for Greenlanders (see the article at the Sydney Morning Herald).

The not-so-good news: the following excerpt from this, and other, articles on this event is a real jaw-dropper:

"US scientists believe Greenland's northern tip is especially rich in oil and gas and they say global warming could help unlock the untapped wealth under the ice-cap and provide a solid foundation for an independent economy."

Let's just hope that these are the same ubiquitous and apocryphal "U.S. scientists" who seem to crop up occasionally in news articles to justify not-to-be-disputed points of view. Let's also hope they have sufficient integrity to be greenhouse sceptics.

It's hard to imagine a more cynical and blithely pragmatic approach to the issue of global warming, whether or not one has doubts about the anthropogenic hypothesis (which would be too large a can of worms ever to be opened on this blog).

Image from cartophilia.com

Cleaning your bathroom with soil science

Andrew.Rate — Tue, 27 Jan 2009 03:09:00 GMT

I was very proud of myself in the weekend. Some time after renovating our bathrooms at home, we found brownish water stains on the otherwise glossy white acrylic vanity tops. Not a good look. Guessing that these were some sort of iron oxide precipitate, I suggested that my wife try a mixture of lemon juice and baking soda on the stain. As you might expect, this was based on a re-interpretation of a commonly used method for selectively dissolving iron oxides in soils, the DCB (dithionite-citrate-bicarbonate) method. The basis of the method was first published by Mehra and Jackson in 1960; I'm more familiar with the method instructions in Loeppert and Inskeep (1996).

To dissolve iron oxides efficiently your [cleaning] solutions needs to have three key properties:

something to reduce Fe³⁺ to Fe²⁺
something to form a complex with Fe²⁺
a buffer to keep the pH high enough.

In Mehra and Jackson's method 1.=dithionite, 2.=citrate, and 3.=sodium bicarbonate. Fortunately this can be approximated using household ingredients. In the lemon juice / baking soda system, the reducing agent (1.) is the ascorbic acid (vitamin C!) in the lemon juice (dithionite is kind of nasty to handle anyway); the lemon juice is also a good source of citric acid (2.). Baking soda is sodium bicarbonate (3.), so no substitution problems there. We applied the mixture to the stain, left it for a moment, and scrubbed with an old toothbrush. Better than abrasive cleaners on an acrylic vanity top, and the stain was completely removed!

I've used adaptations of this method successfully before to remove iron stains from kettles (half a lemon and a teaspoonful of baking soda in the kettle; fill with water, boil, discard, and rinse) and toilets (similar to kettles, but you'll need to add hot water to the bowl...)

Literature

Loeppert, R.H. & Inskeep, W.H. (1996). Iron. In Methods of Soil Analysis. Part 3 - Chemical Methods. (Eds D.L. Sparks, A.L. Page, P.A. Helmke, R.H. Loeppert, P.N. Soltanpour, M.A. Tabatabai, C.T. Johnston and M.E. Sumner) pp. 639-664. (Soil Science Society of America: Madison, WI, USA).

Mehra, O.P. & Jackson, M.L. (1960). Iron oxide removal from soils and clays by a dithionite-citrate system buffered with sodium bicarbonate. In Clays and Clay Minerals, Proc. 7^th Natl. Congr.; Pergamon, London.

P.S. If you're sensitive about such things, it's usually me who cleans the bathrooms in our house. I was redecorating the bedroom at the time...

Soil image from www.agric.wa.gov.au

A good excuse for not posting

Andrew.Rate — Tue, 17 Jun 2008 04:01:00 GMT

I've been doing a lot of marking lately, and not much else, it seems. Certainly no blogging for weeks, sadly.

The reason is my experience of one of the less salubrious hazards of cycling to work; about a month ago I came off second-best in a bingle with a car at a roundabout. I like cycling; it keeps me fit, reduces my carbon footprint and saves me money. But a split second of bad timing, and I end up with an AC joint dislocation (see image at right, with my cyborg implant at bottom so the ligaments can grow back together), and four broken ribs. Could have been worse, probably; in a perverse sense, I'm lucky.

The ability to work from home has been a godsend. My indispensable colleagues have had to pick up what lectures remained in the last weeks of semester, and I've been churning away when I can at marking assignments, lab reports and so on. Next stop exam papers, a PhD thesis to examine, and several ARC proposal assessments - all classifiable under 'marking'. It's surprising to think how much time academics spend on assessing others' work. It could go on all year...

Mood-changing students

Andrew.Rate — Wed, 02 Apr 2008 03:03:00 GMT

Yesterday I could have had a very bad day. Things felt busier than usual, I felt less than well-prepared for a class, and to top it all off I forgot my USB thumb drive on which I had some material prepared the previous evening for a class.

[USB drives seem essential small items these days, along with mobile 'phones. I have a gonzo theory about both technologies; 'phones, fairly obviously, fulfil our need to connect with other humans; on the other hand, our USB drives help us remember important things in our lives (unless, of course, we forget the drive itself). It does seem risky to delegate two of our most important characteristics, communication and memory, to devices... ]

So I turned up to my 9 am 'Earth Surface Processes and Soils' lecture feeling somewhat frazzled and grumpy. Usually in that frame of mind the message doesn't get across so well; that may well have been the case, because (unusually) there were a number of good questions about the material which turned into a useful class discussion. My mood improved markedly. The next class, the one which could have done with more preparation, went smoothly as well.

My afternoon practical class was the last mood changing experience; the students were wrestling with a computer-based problem in Land & Water Management and my interactions with them helpful for both parties, and (certainly from my point-of view) pleasant.

I learned something about being an academic yesterday. Maybe the lesson was just for me; it certainly reinforced an idea that relationships are central to the teaching and learning experience. My anxiety was about the mechanics of teaching; what made the difference was how a group of humans, having a common focus, interacted with one another.

But I'm still lost without my USB...

Journal club Christmas

Andrew.Rate — Fri, 14 Dec 2007 04:25:00 GMT

Two quotes from Bruce Cockburn appropriate to the Christmas season (and the mood it gets me in):

"This bluegreen ball in black space
Filled with beauty even now
battered and abused and lovely"

from the song "Planet of the Clowns" on the album The Trouble With Normal (1983)

This was written in the early 1980s, and there seems little doubt that the "bluegreen ball" has suffered more battery and abuse since then.

In an article "US consumerism poses global recession threat" on the ABC news website, Richard Vietor (Professor of Environmental Management at the Harvard Business School) warns that unbridled (American) consumerism may lead to "catastrophic recession". Easy to point the finger at the USA; there are lots of Americans, but other western countries should not feel too righteous either. I have pessimistic moments when I worry a lot about humanity's impact on our planet. I had one cycling to work this morning in fact, dodging traffic until the sanctuary of the cycle path through the King's Park bushland, prompting me to include Cockburn's bittersweet lyrics above. What will become of Earth? -- the weary Terra may shrug her scarred but resilient skin yet, and rid herself of parasites...

...but Christmas is still a time for hope, as an older Cockburn observes:

"Like a stone on the surface of a still river
Driving the ripples on forever
Redemption rips through the surface of time
In the cry of a tiny babe"

from the song "Cry of a Tiny Babe" on the album Nothing But A Burning Light (1991)

Images from www.cockburnproject.net

A soil scientist's lament

Andrew.Rate — Fri, 14 Dec 2007 02:26:00 GMT

Musings on:
Baveye, P. C. & Jacobson A. R. (2008). Soil science education and the "age of money": reflections and concerns for the near future. Water, Air and Soil Pollution 187:1-4.

This was a guest editorial in Water, Air and Soil Pollution, and I decided it to be worth reading; there's much to be said for a catchy title. The topic summarised in the title seems to be a consistent point of angst for the first author; this editorial self-cites two other articles (Baveye, 2006; Baveye et al., 2006) with similar themes.

Baveye & Jacobson start off by emphasising the importance of soils. Ironically, given the title, this is framed in terms of climate change and the role of soils in carbon cycling. (The irony I perceive is that while the authors decry the inevitable money chasing activity by researchers, any mention of climate change - "big money" science, in anyone's terms - implies a fair amount of money-chasing pragmatism itself. Maybe I'm wrong.) Next, the question is asked about who will be around to conduct the soil science research humanity will need given the pervasive background of climate change. The answer: not many scientists, if the authors' concerns about declining graduates in soil science (and indeed declining numbers of soil science departments themselves) are founded.

There is an assumption in these concerns that only soil science (post)graduates are adequately trained to conduct soil science research, a point made more insistently in another paper (Baveye, 2006). This may be true, but my observation is that in soil science academia, not many soil scientists actually have a first degree (or in some cases, a postgraduate degree) in soil science. Certainly at my University, I can not think of any academic within the soil science discipline who has a first degree in soil science, and only two who have soil science-related PhDs. So Baveye & Jacobson's contention, that only "pure" soil scientists will do, seems unsupported by hard evidence (or, at least, will be subject to many exceptions).

The decline in soil science is attributed to a few factors. One seems reasonable; an insistence on teaching soil science in the context of crop production (where soil science has many of its traditional roots) is probably outdated, especially with " ...the open intention of a majority of students to pursue careers dealing predominantly with environmental issues.". It's hard to argue with that - but not the second point, that "... the fact that soil science faculty do not seem to find that their craft is really exciting any more..." (a point also made in Baveye, 2006). Baveye & Jacobson's evidence for this seems to be the re-naming of many former soil science departments as "earth" or "environmental" something-or-other; we've seen that trend over this way as well, but still soil science research (and teaching!) gets done. The authors are also worried about soil science departments being subsumed into physical geography (or whatever); again, my own discipline may be heading that way, and my interactions with the new discipline have only served to increase my interest in my discipline. Opening up new ideas, and developing new relationships (interpersonal, and between ideas), is exciting too!

The "age of money" referred to by Baveye & Jacobson is linked to their premise that the success of an academic discipline depends on its adherence to the following criteria (reproduced unchanged here):

"A Promise of Money. The field is popularly linked (even if erroneously) to improved chances of securing an occupation or profession that promises above-average lifetime earnings.
A Knowledge of Money. The field itself studies money, whether practically or more theoretically, i.e., fiscal, business, financial, or economic matters and markets.
A Source of Money. The field receives significant external money, i.e., research contracts, federal grants or funding support, or corporate underwriting."

In Baveye & Jacobson's view, soil science departments only do reasonably well at 3.; it's possible that the Australian resources boom may see some success in 1. in this part of the world. Admittedly, the constant focus on money is tiresome for many academics. In the current milieu, it may not be something we can address, so we all (somewhat reluctantly) have to live with it, or so my Head of School tells me from time to time.

Another intriguing issue raised, not in this editorial but in Baveye (2006) , is that scholarly journals (and conferences, apparently) in many cases suppress vigorous academic debate. In addition, many academics (and I can heartily relate to this) are simply too busy to have stimulating discussions about their science any more. It certainly would make for more interesting reading if journal editors took some risks and published more "edgy" material. One journal I sit on the editorial board of is concerned about its low impact factor. My view of the problem for that journal: in most cases, the articles are simply boring. Scientifically sound, they may be, but I think it is true, especially for many of the applied sciences, that much our science gets bogged down in activity and loses the passion for ideas. Perhaps making space for risky thinking and learning from disciplines, such as [some of] geography, which still seem to favour truly creative thinking, will inject some life into soil science. If we get the time.

Baveye, P. (2006). A future for soil science. Journal of Soil and Water Conservation, 61:148A-151A.

Baveye, P., Jacobson, A. R., Allaire, S. E., Tandarich, J., & Bryant, R. (2006). Whither goes soil science in the US and Canada? Survey results and analysis. Soil Science, 171:501-518.

The image is not related to any of the papers discussed!

Soils in the News axed

Andrew.Rate — Fri, 12 Oct 2007 08:38:00 GMT

I apologize for lazy blogging, with a promise to not just do listings of news articles about soils. If something REALLY interesting comes up I'll let people know, but really that's not what this blog is all about.

Unfortunately that means that I have to get motivated about writing up articles I've read recently. At least I have done the reading ... but getting the thoughts and margin notes into readable blog posts is a limiting factor.

So the posts may be less frequent than weekly - but at least they'll be interesting. To me anyway.

So... that was that

Andrew.Rate — Thu, 16 Aug 2007 06:10:00 GMT

Just rode my bike back from what will be my last lecture of the Semester. Just over half the class of Introduction to Geochemistry students gained (hopefully!) some benefit from working through past exam questions.

I reminded myself, inadvertently, that there is not really that much to be said about a topic in three weeks of lectures. Particularly when I'm trying to get across some fundamental material about my discipline - when it comes down to asking exam questions, they're mostly variations on a theme or even repetitive from year to year. Students with good exam technique will recognise this and exploit it - more power to them.

Oh yes - this is supposed to be a journal club blog. The club meetings have been at best sporadic this year and attendance is dwindling. Although I did talk to one of the PhD students who attends sometimes who mentioned that she used one of the papers (Davidson & Janssens 2006 - see here) we discussed for teaching first-year ecology. That's where I've gotten the most benefit so far from the Journal Club - it has enhanced my teaching.

the story of a lecture

Andrew.Rate — Mon, 06 Aug 2007 06:01:00 GMT

This is not really a research issue - but having just completed a lecture, it occurs to me that I'm most satisfied with what I present when there is some sort of narrative structure to a lecture. Today's story discussed the development of models for adsorption in soils, gradually adding more complexity until the eventual conclusion (with a small postscript of a digressive nature at the end), so there was some sort of plot to be followed.

This isn't always reflected in student attendance, of course. Last week I stood in front of the same third-year soil science class and gave what I felt was the best lecture I'd given in that unit - to an audience of five students. My gentle wander through the development of theory about bioavailability in soils (see this blog's post on the terrestrial biotic ligand model, which helped me get my thoughts around some of this) was pleasing to me and apparently engaging to students, partly because there was a story to be told.

It would be easy (and conceited) to assume that all good lectures have an element of narrative. And an even more headstrong generalization to claim that any scientific presentation, a thesis included, will benefit from having a strong story thread. But I find that it works for me, and helps me get my head in order.

I've been thinking about this for a while, and I assume that others more attuned to things educational have too. But I haven't found much on the topic of narrative structure in [scientific] lectures - I wonder if anyone else has?

Oh, and by the way, the image was thoughtfully prepared for me as part of an assignment for a soil science unit last semester. The perpetrators can identify themselves here if they so wish.

the legend of Bawshou

Andrew.Rate — Mon, 06 Aug 2007 01:59:00 GMT

So I was reading a book, "Bawshou Resecues the Sun" to my daughter in the weekend and it occurred to me that this is yet another instance where soil appears in a significant folk story.

"Bawshou Resecues the Sun" is based on a traditional Han Chinese story about the sun being stolen by the King of devils (variously, a powerful dragon). Bawshou's father dies in an attempt to rescue the sun, even when aided by the golden phoenix. Bawshou continues the quest, helped by the same phoenix, but his success hinges ultimately on reaching the home of the devils across the mighty Eastern ocean. He is able to do this because some helpful villagers give him a packet of "earth" (for which I read soil), which transforms itself into a chain of islands as he sprinkles grains upon the water.

It's also interesting how here, as in many other contexts, the word "earth" is used synonymously with "soil"... but that's for another time.

Bawshou Rescues The Sun, by Chun-Chan Yeh and Allan Baillie, illustrated by Michelle Powell. Ashton Scholastic, Sydney, 1991.

土壤

Christmas and soil

Andrew.Rate — Wed, 20 Dec 2006 06:07:00 GMT

Ancient literature like the Christian Bible uses soil or earth as a metaphor for a number of things, and since it's just before Christmas I wondered if something soil-related could be found in the gospel rendition of the Chritsmas story. No such luck . . . but the story below was told by the man of the season himself, and uses soil as a powerful metaphor of the human heart. So, I thought it oddly appropriate at this time of year which is also, unfortunately, characterised by our manic consumerism which I believe approaches mass hysteria in its disturbing intensity.

That same day Jesus went out of the house and sat by the lake. Such large crowds gathered around him that he got into a boat and sat in it, while all the people stood on the shore. Then he told them many things in parables, saying: "A farmer went out to sow his seed. As he was scattering the seed, some fell along the path, and the birds came and ate it up. Some fell on rocky places, where it did not have much soil. It sprang up quickly, because the soil was shallow. But when the sun came up, the plants were scorched, and they withered because they had no root. Other seed fell among thorns, which grew up and choked the plants. Still other seed fell on good soil, where it produced a crop—a hundred, sixty or thirty times what was sown."

Matthew 13:1-8 (Today's New International Version)

image from http://www.ebibleteacher.com/

Someone else's thesis

Andrew.Rate — Wed, 06 Dec 2006 03:55:00 GMT

It occurs to me that this blog is not like other blogs. So, in the interests of fitting in to this erudite community, a few posts must, of course, be produced with truly blog-like characteristics. So this entry may be of the whimsical persuasion, or the world-weary. I would hope for insight, but that of course will be clouded with lack of sleep and too much cheap coffee.

The reason for the sleepless night, partly, was my need to finalise the corrections for a student's MSc thesis. The student had started studying elsewhere, a few thousand kilometres away, and had done as much as they could from their end. These days, it's in the best interests of an academic and their School to get postgraduate completions . . . so I was doing my bit to keep Commonwealth funding flowing, by working on someone else's thesis. Plus, of course, I want it looking as tidy as possible because I'm down as a supervisor; sloppily-presented theses can be (at least privately) embarrassing.

A very late night and a dubious breakfast at the Guild cafe, and it's nearly there. Just some final checking before it all goes to UniPrint with the inevitable T-form. Of course there are some errors to fix and the pdf is a whopping 25 Mb. I'm thinking it's time to knock off for the day...

By the way, the thesis was about soils. Sort of.