Better than conservation, regenerative agriculture

Agriculture and soil. Pollution control, soil remediation, humus and new agricultural techniques.
VetusLignum
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Re: Better than conservation, regenerative agriculture




by VetusLignum » 05/07/19, 16:25

izentrop wrote:Yep, a commercial site as a reference :?: well it is not clear and a recent study confirms it: Ratio mushrooms / bacteria: bad historical interpretations and potential implications https://www.sciencedirect.com/science/a ... 9X18300389
The relative contribution of bacteria and fungi can be better assessed using the F: B assimilation ratio, rather than the biomass ratio or the production ratio. However, uncertainties remain in the estimates of microbial production and assimilation due to their complex responses to soil wildlife activities. Regulation of soil fauna on microbial biomass, rate of turnover and respiration, as well as associated changes in energy allocations in the soil food chain should be highlighted in future studies.

Image


What I have quoted is the consensus of many soil microbiologists.
The article you cite, and which more or less calls it into question, is very recent, and I am not in a position to judge its relevance. I am waiting to see what Elaine Ingham & co will answer.
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izentrop
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Re: Better than conservation, regenerative agriculture




by izentrop » 06/07/19, 15:38

VetusLignum wrote:What does a 1% ratio mean? A biomass of 1 fungus per 100 bacteria?
The FFA ratios of PLFA, RNA and proteins were calculated using the amounts of lipids, the proportion of sequences and the abundance of proteins, respectively. The proportion of fungi in relation to bacteria was expressed as follows:

% proportion F: B = Fu n gun l in de xB acterial in de x × 100 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4977315/
and in this same study from 2016 where they analyze a grassland soil
In order to study the link between microbial community structures and the soil carbon cycle, we chose two soils from the Jena biodiversity experiment, a large-scale grassland diversity experiment established in 2002 in Jena, Germany (Roscher et al., 2004). Soils were selected based on the composition of the microbial community derived from PLFA 2007 (Lange et al., 2014).), So that the soils had similar physical and chemical properties, but differed in the structure of their microbial community, and in particular in their F: B ratio. Therefore, the two soils were named "low soil F: B" and "high soil F: B". This nomenclature has been followed throughout this report. The two soils had a similar soil texture (44,6% sand, 39,6% silt, 15,8% clay) and pH 7,75. The C, N, and C: N ratios of soils were also very similar at 2, 0,2, and 10,2%, respectively (Supplementary Figure S1). The two soils differed in the number of plant species (four in the low F: B soil, eight in the high F: B soil) but not in the number of functional groups in the plant ( one grass, one small grass, one tall and legume in both soils). Soil was collected from stainless steel cores in April 2014 to a depth of 0-10cm (from three spatially replicated plots for each soil class), sieved (<2mm), all visible roots were were removed, homogenized and stored 12 days before the establishment of the mesocosms.
I pass the detail of the measurement protocol
Before setting up the experiment on the mesocosm, the composition of the microbial community using PLFA biomarkers was reassessed with soils from the same diversity plots. The total bacterial PLFA content was 18,46 ± 0,05 and 23,55 ± 0,23 μg / g; while the fungal PLFA content was measured at 0,52 ± 0,002 and 0,99 ± 0,01 μg / g in soils with low F: B content and high F: B content, respectively.The proportion of fungi per cent compared to bacteria has been estimated at 2,8 ± 0,01 and 4,2 ± 0,07 at low F: B and high F: sol B, respectively (Figure Figure 1A 1A). The F: B ratio, derived from PLFA, of the high F: B soil microbial community was 1,5 times that of the low F: B soil (single-factor ANOVA; p <0,001 ).
So we stay within 1 to 5%
VetusLignum wrote:What I have quoted is the consensus of many soil microbiologists.
Which :?: : Wink:
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VetusLignum
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Re: Better than conservation, regenerative agriculture




by VetusLignum » 10/07/19, 10:35

izentrop wrote:
VetusLignum wrote:What does a 1% ratio mean? A biomass of 1 fungus per 100 bacteria?

and in this same study from 2016 where they analyze a grassland soil
So we stay within 1 to 5%


In this study, they certainly speak of a low and a high F: B ratio; but this relates to this study, which was carried out on flooded grassland soils.
In absolute terms, these ratios remain very low, in accordance with what is expected on this type of soil.

So when, in the presentation in French that you quoted, they say that a ratio of 5% is too high (in absolute terms) in mushrooms, I cannot understand.

Below an extract from https://books.google.ie/books?id=r3ZsL47QiVQC (click on it twice to see it bigger):
fb2.png


As a bonus an extract from https://books.google.ie/books?id=BJWDDwAAQBAJ :
Fb.jpg
FB.jpg (420.46 KB) Viewed 3845 times
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Did67
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Re: Better than conservation, regenerative agriculture




by Did67 » 10/07/19, 12:10

There is some consistency:

a) "open areas" - meadows - are dominated by short-cycle plants; their diet is dominated by nitrates; presence of legumes (symbiosis therefore bacteria); nitrifying bacteria, etc ... We dominate matters balanced in fresh azoten, cellulosic never woody; bacteria and fungi break this down ... Draw!

b) forests store woody fiber, which is very poor in nitrogen; they recycle wood more; only fungi can do this, not bacteria; but they stop at the level of ammonium ions; conifers absorb nitrogen in ammoniacal form, which leads to acidification (a basic ion, ammonium is removed); which "helps" the mushrooms ... 10 - 0 for the fungi.

Deciduous forests are a bit of an ass between these two chairs ... There is dead wood, but also little or no woody dead leaves (the veins); before the leaves settle in the spring, non-woody plants complete their cycle, then "disappear" (lily of the valley, bear garlic, anemones) ... 2-0 for the fungi ...

There are, however, a few "curiosities": carrots, known to be very dependent on mycorrhization, are cited as preferring a low F: B ratio ??? It is more consistent for cereals, which are known to be low dependent. Corn is moderately.

But in a complex living system, the causal links are multiple, and other factors can work "in the other direction", or even dominate!
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VetusLignum
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Re: Better than conservation, regenerative agriculture




by VetusLignum » 12/07/19, 12:18

Did67 wrote:
There are, however, a few "curiosities": carrots, known to be very dependent on mycorrhization, are cited as preferring a low F: B ratio ??? It is more consistent for cereals, which are known to be low dependent. Corn is moderately.



First, a ratio between .3 and .8 is not that low. There are still quite a few mushrooms in there.

Second, these optimal ratios for cultivated vegetables are determined by looking in which biotope the wild version of the cultivated plant grows.

But this induces a number of biases.

First, these natural environments are environments where there is strong competition; so one plant grows there because it performs relatively better there than others.
But in an artificial environment like a garden, where man manages competition, we no longer wonder what is the environment where the plant performs relatively better than others; we wonder what is the environment in which it performs best in absolute.
Thus, David C. Johnson argues that the optimal F: B ratios for our crops are higher than we think.
agriculture / the-garden-of-lazy-garden-more-than-bio-without-fatigue-t13846-13670.html? Hilit = johnson # p358614

Another bias is that of variety; different varieties of the same plant do not all have the same behavior.

Below a little reading on the natural biotope of the carrot:
https://permaforet.blogspot.com/2014/07 ... ntain.html
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izentrop
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Re: Better than conservation, regenerative agriculture




by izentrop » 26/12/19, 23:20

Where does this extraordinary claim of the thin layer of annual compost come from?
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VetusLignum
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Re: Better than conservation, regenerative agriculture




by VetusLignum » 27/12/19, 00:04

izentrop wrote:Where does this extraordinary claim of the thin layer of annual compost come from?

We are dealing here with an American association communicating around ecology for city dwellers.
One of the components of their actions is precisely to encourage city dwellers to better recycle their organic waste.
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