Technical term 4 water thru-flow reducing soil nutrient availability?

New Topic
This topic has been archived, and won't accept reply postings.
 Timmd 24 Jun 2022

 I feel like I've read one somewhere, but I can't find where I did, or determine if I've remembered it correctly.

Has anybody come across such a term?

Many thanks.

Tim

Post edited at 15:10
In reply to Timmd:

How about Leaching.

 jimtitt 24 Jun 2022
In reply to cumbria mammoth:

Yup, nutrient leaching.

 DaveHK 24 Jun 2022
In reply to Timmd:

Eluviation is similar.

OP Timmd 24 Jun 2022
In reply to DaveHK:

That was the term, how is it slightly different if it is similar, or is it just a different name for essentially the same thing?

 wintertree 24 Jun 2022
In reply to Timmd:

Do you really mean availability?  They’re present but not accessible in bone dry soil; some water content will mobilise their diffusion making them accessible to the plant roots; more will leach them away, reducing their accessibility.

Seems like the terminology isn’t quite right; this is more about reduction in volumetric density through flow driven removal.  To me “availability” sits in an Ill defined position between the physical density and the practical accessibility.

I appreciate this is terminology you are given.

Post edited at 15:31
OP Timmd 24 Jun 2022
In reply to wintertree:

I think I've got enough to be searching on what to find out about now. 

It seems to be that water availability and nutrient uptake (cationic exchange) and pH are combined, do you know anything about pH buffering, what the term of buffering relates to/the factors involved?

Post edited at 15:55
 DaveHK 24 Jun 2022
In reply to DaveHK:

Leaching is a general term. Eluviation is material being washed out of an upper layer, illuviation is it being re-deposited further down the soil profile. The two together are translocation.

Edit: I'm not aware of these terms being used with regard to nutrient availability, they're just physical processes.

Post edited at 16:33
In reply to Timmd:

> I think I've got enough to be searching on what to find out about now.

I think I asked on your other recent, related thread, what it is you are studying, or trying to find out about.

If you gave us that context, it might help us to guide you to suitable instructive material.

> It seems to be that water availability and nutrient uptake (cationic exchange) and pH are combined,

Well, you need water to put nutrients into an available state, and to create an aqueous solution with a given pH.

https://en.wikipedia.org/wiki/PH

> do you know anything about pH buffering, what the term of buffering relates to/the factors involved?

A pH buffer is (for acid buffers) a weak acid and its conjugate salt (or a weak base and conjugate salt for alkaline buffers). The two interact to prevent changes in pH, by changing acid to salt, or salt to acid, mopping up or releasing H+.

https://www.google.com/search?q=ph+buffer

OP Timmd 24 Jun 2022
In reply to captain paranoia:

It's to do with Tideswell Dale, and the soil pH there, and how it's affected by the bedrock and and any water through-flow (or not as the case may be). 

I just need to show an understand really, at this level it's about the correct use of terms and how something about the process.

Post edited at 16:48
In reply to Timmd:

To what end? Obviously not for gardening...

OP Timmd 24 Jun 2022
In reply to captain paranoia:

The end isn't so important, it's understanding what buffering 'is'.

 Doug 24 Jun 2022
In reply to Timmd:

Many years ago when I studied soil science as an undergraduate, our main text was 'Principles and Practice of Soil Science' by  Robert E. White, which unless its been revised is no doubt long out of print. It covered all of this basic soil chemistry & how it interacts with soil physical properties. There must be similar texts in your university library which should help you understand the basics & then allow you to apply to the situation in your study area.

Good luck

In reply to Timmd:

> The end isn't so important, it's understanding what buffering 'is'.

If we are to advise usefully, we really need to understand the context of your enquiries; I still don't. It sounds like Doug's recommended reading ought to answer your questions, if you're interested in soil chemistry.

The links I posted above ought to help you understand buffering, and how a pH buffer works to keep pH constant, and the limits of that pH buffer operation.

 gethin_allen 24 Jun 2022
In reply to Timmd:

Buffering of anything just means keeping something the same. In the case of pH it's all to do with keeping the pH constant. This is normally achieved by having an acid and a base at specific concentrations so that an equilibrium is reached. If external forces are applied trying to push the pH in one direction either the acid or the base dissociate (free up more H+ or OH-) to mop up the acid or base that is trying to move the pH from the desired point set by the buffer component concentrations. In the case of a natural environment there will be loads of different components in the buffer, but if you add a load more of either acid or basic components you will eventually shift the pH. The pH is important when it comes to bioavailability as many compounds are insoluble at certain pHs therefore if you change the pH some stuff will dissolve and other stuff fall out of solition.

Hope that makes sense and is useful.

OP Timmd 24 Jun 2022
In reply to gethin_allen:

Yes it does, it seems to be true that the amount of water can have an effect as well. I will need to read more on it, but that does make sense.

 Ridge 24 Jun 2022
In reply to gethin_allen:

Really good explanation of buffering. I think the issue a few of us are having is understanding the terminology in the context of Tim's course, as meanings seem to change in respect to disciplines.

 apache 25 Jun 2022
In reply to Doug:

Doug, you’re showing your age! But fortunately it’s now in its fourth edition

 Doug 25 Jun 2022
In reply to apache:

think I had a copy of the then newly published 2nd edition

Its probably still with a lot of old books that a good friend back in Scotland is looking after for me until I can arrange for them to be shipped to France or manage to visit him when I don't have a weight allowance limiting what I can bring back

edit to add - just checked the dates, I must have the 1st edition.

Post edited at 17:27
 hang_about 25 Jun 2022
In reply to Timmd:

I'd use the term leaching. You need an Eh-pH diagram. The form a mineral will be found in depends on the pH and redox.

 Toerag 27 Jun 2022
In reply to Timmd:

Are you talking about thru-flow washing away nutrients to leave a nutrient-deficient soil, or altering the soil chemistry so the nutrients don't come into solution in the first place?

 obi-wan nick b 28 Jun 2022
In reply to Timmd: How about flushing?

OP Timmd 04 Jul 2022
In reply to Timmd:

I seem to have got a provisional 1st for the work and module this was related to (100% of the marks), in speaking about ammonium in cationic exchange, and illuviation and leaching where it seemed appropriate. Ta to all for 'sparking thoughts'.

Have bought the book the latest online edition of Principles & Practices Of Soil Science. Somewhat surprised at the provisional 1st, but I'm not going to argue, one more provisional mark and the final marks to go.

Post edited at 14:42

New Topic
This topic has been archived, and won't accept reply postings.
Loading Notifications...