[Stoves] biochar in basic soils?

[Frank Shields]

Dear Rolf,


I agree that one first needs to see effects from  'practical experience' but that is only site specific. Most important is when someone observes a response (positive or negative) that the cause is determined. And this involves science. Otherwise we just have pretty pictures. I agree with all the great responses Kevin gave - but would like to add another that is often overlooked; Biochar should be looked at for the long haul. The response one sees in year one or two or three  is interesting but it's what has occurred when one averages over many years that’s important. What the biochar does to the soil long after the pH adjustment from the carbonates and oxides are long gone is what we should focus on. Like drainage, nutrient holding, water retention etc. etc. that will last years because this is why we use biochar. 

Regards

Frank


Frank Shields
Control Laboratories, Inc.
42 Hangar Way
Watsonville, CA  95076
(831) 724-5422 tel
(831) 724-3188 fax
www.biocharlab.com





 


-----Original Message-----
From: Stoves [mailto:stoves-bounces at lists.bioenergylists.org] On Behalf Of Rolf Uhle
Sent: Friday, December 14, 2012 3:35 AM
To: Discussion of biomass cooking stoves
Subject: Re: [Stoves] biochar in basic soils?

Thanks Kevin,

for your answer.

I am quite aware of most of these factors and of their interdependance.

That´ s why I ask for practical experience.

Chemistry, soil science and technology are very interesting, but they cannot replace the practical, hands on experiments with varying conditions.

Therefore I ask again if anyone has practical experience with biochar application on carbonate derivated soils with some loess mixed.

Thanks again and have a nice WE

Rolf 






Am Donnerstag, 13. Dezember 2012, 15:02:18 schrieben Sie:
> Dear Rolf
>   ----- Original Message -----
>   From: Energies Naturals C.B.
>   To: Discussion of biomass cooking stoves
>   Sent: Thursday, December 13, 2012 4:18 AM
>   Subject: [Stoves] biochar in basic soils?
> 
> 
>   Hallo all,
> 
>   this is a question I have asked quite often, but perhaps never on 
> the list .
> 
>   Whenever I read about the benefits of biochar, it is almost always 
> in relation with distinctively acid soils.
> 
>   Does anyone know the effect of biochar, itself beeing mostly basic, 
> on already basic soils ?
> 
>   # I would suggest that the reason why your question has not been 
> answered already is that it is much more complex than it first 
> appears. # Firstly, the method of testing biochar for pH is very 
> important. If a given biochar is added to distilled water, and a pH 
> reading is taken, this pH reading will probably not be a meaningful 
> indicatior of the degree to which a biochar will modify soil pH. For 
> one thing, there may be no indication of the quantity of biochar added per litre of water used in teh pH test.
> 
>   # Secondly, the amount of biochar added to a given soil is very 
> important. Clearly, the impact of 1 Tonne per HA will be less than an 
> addition of 10 tonnes per HA.
> 
>   # Thirdly, the nature of the soil to which the biochar is added will 
> heve a large effect on the pH change. A given addition of biochar to a 
> sandy soil will have a very much larger effect on pH than would the 
> same rate of addition have on a clay soil with a large buffering effect.
> 
>   # Fourthly, the species of material responsible for the pH increase 
> is very important. If a soil was basic because of relatively high 
> calcium, but was deficient in potassium, a biochar with a high 
> potassium content could result in a significant benefit to plant 
> growth, greater than the detriment associated with a rise in pH.
> 
>   # Fifthly, the species of biomass and its preparation prior to 
> conversion to biochar can be very important. Biochar made from fresh 
> grass and leaves would be expected to have a higher pH than would 
> biochar made from leaves and grasses that were weathered. Biochar made 
> from de-barked wood would be expected to have a higher pH than would biochar made from de-barked wood.
> 
>   Sixthly, the process used to manufacture biochar could have a 
> significant effect on its pH. A process with a high yield of biochar 
> may have less "free ash" available for changing the apparent pH of the char.
> 
>   Seventhly, post-processing of a biochar can have an influence on pH.
> Biochar that is screened to remove ash would be expected to have a 
> lower pH than would biochar that was not screened for ash removal. 
> similarily, such screenings would be expected to have a significantly 
> higher pH than would the coarser char particles remaining on the screen.
> 
>   There are likely other important factors impacting on the pH effects 
> that biochar additions could bring to a given soil.
> 
>   Best wishes,
> 
>   Kevin
> 
> 
>   Rolf
> 
> 
> 
> < Big snip of great info)
> 
>