Talk:Soil organic matter

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Contents 1 Decomposability? 2 Soil Science and "organic matter"? 3 Major considerations for this article 4 Requested move 5 Soil organic matter

[edit] Decomposability?

This is related to the discussion in the two sections below, but in the interest of readibility I wanted to give this question its own section. Right now the article defines organic matter based on its ability to decompose... and this seems quite strange. This is neither the vitalism-derived notion of "organic" as "biotic" (i.e. "organismal"), nor the chemical-biological definition of "organic" based on atomic makeup. As Pengo has pointed out below, this article should include the various meanings of its entry, but I am simply taken aback by a definition of organic as decomposable. I'm wondering what others think about this idea and how it should be made a part of a revised version of this article. Ventifact 01:09, 13 September 2006 (UTC)

[edit] Soil Science and "organic matter"?

This is mentioned below, but I wanted a less cluttered place to get a clear answer to a question that's very important for the future of this article: what specific meaning, if any, does "organic matter"/"organic material" have in soil science? It would be very useful for someone who is well educated in this field to explain any meaning organic matter has in that field, and also how it differs from the following: biotic matter, detritus, litter, humus, and the defintion of organic matter used in chemistry and biology. Thanks. Ventifact 00:53, 13 September 2006 (UTC)

OK, so I decided not to wait for help, and I went looking on the internet for an answer to my question (gee, what a creative solution). Looking at soil science websites, here's what I found:

1) Soil organic matter = biotic matter, i.e. anything from an organism; this includes living organisms, detritus/litter, and humus, (and would include chemically inorganic material that is biotic). This definition comes from the United States Department of Agriculture (see page 11). Additionally, in Wikipedia's humus entry, humus is said to be a major constituent of soil organic matter.

2) Soil organic matter = detritus/litter, i.e. any dead organismal debris that has not yet become humus. This comes from the Natural Resource Conservation Service (formerly the Soil Conservation Service, and a sub-organization of the USDA).

3) Soil organic matter = humus, exclusive of anything biotic or chemically organic that has not decomposed into humus. The Soil Science Society of America has a Glossary of Soil Science Terms, from which this definition comes.

4) Soil organic matter = chemically organic matter in soil. This usage is not defined anywhere explicitly that I could find but seemed to be meant in many circumstances, for example journal articles like this one and many more from similar journals. Also, the glossary of the Soil Science Society of America seems to use the term this way (see for example the entry on fertilizer).

In a practical sense I am not aware of much of a difference between biotic matter in soil (#1) and chemically organic matter in soil (#4), because inorganic biotic matter like bones, shells, and teeth are not major soil constituents. Application of synthetic organic compounds to soil would be the important exception to overlap between meaning #1) and #4 I think. This would all be relatively simple if we didn't also have two more definitions in use (#2 and #3) -- moreover, these definitions are opposites! This leaves us with a difficult situation. --Ventifact 04:13, 14 September 2006 (UTC)

So I did actually find a more explicit definition matching number 4 above, from a University of Minnesota webpage. Ventifact 05:03, 14 September 2006 (UTC)

Nice research. Rather than fleshing it out here, I've done some major changes to the article to reflect the above definitions -- trying to make the article encompass them all rather than shoe-horning it into a single definition. The changes are rough and unreferenced and there's a lot of room for improvement, so please feel free to rewrite the lot still. The main thing still lacking is some information on where each of these definitions are used. —Pengo ^{talk · contribs} 07:42, 14 September 2006 (UTC)

[edit] Major considerations for this article

Please give your thoughts on the following concerns I have about this article:

1) Discussing vitalism is important when discussing organic matter

2) "Organic matter" here seems to be being discussed only in terms of its use as soil science jargon, not in the sense of "matter that is organic," "organic" being meant in the broadly understood scientific sense

3) This broadly understood technical/scientific sense focuses its definition on the presence of carbon (with a few caveats), not on whether something can decompose (note that someone has mangled my previous explanation of why clamshells are inorganic so that it's completely circular in reasoning now: 'shells are inorganic because they don't contain organic molecules')

4) Confusion between biotic matter and organic matter is common and should be addressed here

5) As for the "informal" nature of the term "organic," when I put that in I was pointing out that although it sometimes is used informally, it isn't solely an informal term. As such it is worthwhile in an encyclopedia to explain both the term's informal and formal usages. (Consider the idea of significance -- the term has an informal meaning of "importance" that many non-specialists might confuse with its very specific technical meaning within the field of statistics.)

I intend to rewrite the article soon along the lines of some of the previous versions so please let me know what you think. Ventifact 06:01, 12 September 2006 (UTC)

I'd also like to note that the sentence "In soil science, organic matter refers to that of soil" is akin to saying "in poetry, 'diction' refers to that of poems." 70.36.0.149 07:46, 12 September 2006 (UTC) oops I got logged out...Ventifact 07:47, 12 September 2006 (UTC)

This article is about the soil sciences meaning of "organic material", and currently only talks in those terms. If you wish to rewrite the article to define organic material as "material made of organic compounds" then please write a new article called "organic material (chemistry)". I don't find the term "informal" particularly useful, as there are already mutliple overlapping meanings of organic in both scientific and common uses.

It seems you think that the chemical definition of "organic" is the "broad" definition. Actually, that's the very narrow and precise definition — very much the opposite of a broad definition. In its broadest sense "organic" does not mean carbon. It means organism — a living thing. Life has many facets, of which carbon-basedness happens to be the one focus of chemistry. "Organic material", however, does not simply mean "material of organic compounds", even if it's not far from it. If that was the only focus of this article, then there would be no need for an article, and instead it would simply be a redirect to organic compound.

Please note that when you taken the broader sense, the sentence about vitalism makes no sense. Of course organic material was thought to come from living organisms, that was by definition. It is the definition of organic substances that has changed, not just the understanding. Likewise, the clamshell thing isn't circular when you consider an "organic molecule" refers to a very specific thing, defined separately to organic matter.

So please go ahead be bold, but also consider the soil sciences meaning, and don't turn the article into a carbon copy of organic compound (npi).

The highly overlapping meanings ought to be able to coexist on the one page, but if you really feel they can't, then, well, start organic material (chemistry) or something, but I'm sure you'd rather not. Well, good luck cleaning up this mess.

By the way, that non sequitur about soil science was always meant to be expanded (e.g. with how you measure organic matter in soil and such) but that never happened. oh well. I should spend more time writing articles and less time arguing about them. —Pengo ^{talk · contribs} 16:20, 12 September 2006 (UTC)

Thanks for your quick response and your helpful points. I would have been bold except that everything I intend to put into the article I have previously put there only to have it removed or mangled. While I disagree with those edits for the most part, I do respect the fact that other users might have had valid reasons for their edits. So, instead of everyone being bold back and forth, I thought it would be best to figure out which of all our ideas for this article were bad and which were useful.

One question I have about this article is does it even need to exist? After all, there are separate entries explaining what it means for something to be organic and what matter is. "Organic matter" would just be material that is organic, right? Assuming that this article had reason to exist, I understood it to be a place to explain, in terms that involved as little chemistry as possible, the nature of organic matter, including historical understanding of organic material (e.g. vitalism) and its relationship to biotic material. Biotic matter has its own article, and there you'll see that material manufactured by organismal processes is biotic.

In my experience, organic is only used as a synonym for biotic by folks who are not in the life sciences or chemical sciences and for whom the distinction between organic and biotic material is unimportant (for example geologists and non-scientists); as a result, I don't think this usage has priority. I do think it's important to recognize and discuss this usage of the term, but this is a usage I would consider informal/non-technical. The difference between the informal meaning (i.e. "biotic") and the technical meaning (its chemical definition) naturally leads to a discussion of vitalism. That is, "organic" used to mean "biotic" because of vitalism, so understanding the fallacy of vitalism clears up confusion about usage of "organic." Does that make sense?

As for the soil science aspect of this entry, none of the article's soil-specific information is clearly labeled as such, and so, since I'm not a soil scientist I cannot tell the difference between soil-specific information and information that is simply scientifically incorrect. It may turn out that the only reason for this article to exist -- since organic and matter have their own entries and combining an adjective with a noun is an easy task that doesn't require an encyclopedia entry -- is to discuss organic matter as a specific term exclusive to soil science. However as I said, I know little soil science and have no way of knowing this. I've checked the entries on soil science and all the entries on its major subdisciplines. The only place I found a use of "organic matter" that would not match usage by biologists and chemists was in the humus article, in which it was clear that the author meant detritus/litter, in contrast to humus, which is amorphous. I'm not saying this usage is incorrect; however, I am unclear what meaning "organic matter" is supposed to have, if any, that isn't redundant with either "biotic matter" or "detritus." I'd also like to point out that the article right now mentions humus as an example of organic material, whereas the only entry on Wikipedia in which I could find use of organic matter not in the broad scientific sense referring to substance's chemical makeup was the article on humus, and in which the term "organic matter" was used in contrast with humus. Thus I can infer no particular meaning this term is supposed to have in soil science.

As for the queston of broad/narrow definitions, I should clarify. By "broadly understood scientific sense" I meant the sense of the term that the majority of scientists who use the term understand it to mean. That is, most scientists who ever hear "organic matter" and use the term as part of their discipline would not, upon hearing the term, think only of detritus. Also, there is a difference between breadth and specificity. That is, boundaries/definitions can at the same time be both broad and specific. Breadth and specificity are not mutually exclusive; for example, the rule stating all adult U.S. citizens are allowed to vote unless they are felons is quite broad -- it includes almost everyone -- but it is also very specific -- there is no gray area of folks who might or might not fall into the eligible/ineligible voter categories based on this rule. Similarly, what I call the "formal"/"technical" meaning of "organic matter" is very specific, but it is also very broad, with no inherent contradiction in those facts.

So this is where my view on the article stands now:

1) I'd like to hear from someone confident in soil science who can explain what specific meaning, if any, this term has in that field.

2) If this term is an important and distinct usage in soil science, then that should become the focus of this article, but it needs to be clearly stated from the start of the article. I'm thinking of an opening sentence that goes something like this: Organic matter is a term used in soil science to refer to... or perhaps In soil science, organic matter is... It would need to be followed somewhat closely by an explanation that this usage differs significantly from the term's usage within biology and chemistry, with links to the broader usage of "organic."

3) If this is not to become an article focusing on soil science, then the community needs to decide if this article should exist at all. I.e., what is this article needed for that other articles don't already accomplish? Should it become a redirect? Maybe it should become a less technical treatment of the topic? Perhaps the disambiguation page of organic would actually be a better place to give a discussion of the different usages of "organic," because right now it is full of links but it's difficult for a reader to understand the relationship between different meanings?

4) I'd rather not drastically alter, delete, or transform this article into a redirect without hearing from other folks first. However, if 1) does not happen then this article will have to go back to a condition similar to the one it was in several months ago, when I last rewrote it, because right now it is too incoherent and incorrect: it is simply misleading to any reader who does make sense of it.

Thanks again for input. Ventifact 00:47, 13 September 2006 (UTC)

By the way, my last overhaul of the article looked like this: http://en.wikipedia.org/w/index.php?title=Organic_material&oldid=47600716

This is the general gist of where I would be thinking of taking this article again if no one can clarify this article's relationship to soil science. Ventifact 01:00, 13 September 2006 (UTC)

I moved half of that version of the article to biotic material. The rest is a mix of the soil science meaning (decomposable matter), very broad meaning (once living), and the chemical sense (organic compound). There's nothing wrong with deliniating all those (overlapping) meanings as long as it actually explains when it's switching meanings. BTW, try search for define:organic matter on Google. Unfortunately I don't know enough about soil science to contribute more on that front. —Pengo ^{talk · contribs} 11:28, 13 September 2006 (UTC)

[edit] Requested move

See the 3 sections above this one, especially Soil Science and "organic matter" and Major considerations for this article on problems in this article. To summarize the current situation as it pertains to this move request, the question of what exactly an entry on "organic matter" should say has led me to try to figure out how the discipline of soil science defines organic matter. It turns out it has a number of extremely differing definitions, but I discovered that the one thing that seemed most dependable in all the variability was that the term is properly "soil organic matter." This is a relatively small deal, but I wouldn't mind input from a soil scientist before moving this article (the bigger question is what to do with the article's content, see below). Ventifact 04:43, 14 September 2006 (UTC)

Support, again i'm no expert, but I'd agree "organic matter" would be a better term. But from this discussion i'm starting to wonder if "soil organic matter" might be a more appropriate title. :) But "organic matter" is good. —Pengo ^{talk · contribs} 06:54, 14 September 2006 (UTC)

I came to this article looking for information on matter that contains carbon. Why does Organic matter redirect to an article about soil? I don't care about soil. Perhaps I should check Encyclopedia Britannica instead. -- JHP 03:12, 12 December 2006 (UTC)

[edit] Soil organic matter

There is consensus regarding the basic elements of som. Obviously there is a lack of consensus on what elements are included or excluded. What it boils down to is "pick one". Just say early in the section what you mean by by the term and use it consistently. KAM 15:59, 19 November 2006 (UTC)