Tables; Scale For Soil Activity; Characteristics Of Quality-Assured Culture Substrata - PRONOVA Stelzner pH AGRAR 2000 Technical Instructions

GB
6.

Tables

6.1 Scale for soil activity:

Activity, g/litre
0,00 – 0,05
0,05 – 0,10
0,10 – 0,20
0,20 – 0,40
0,40 – 0,80
0,80 – 1,20
1,20 – 1,40
> 1,40
For sixty years we have known that it is not
the quantity of dissolved salt but the salt
activity which effects chemical reactions
and physical processes. That also applies
without restrictions to nutrient absorption by
plants.
6.2 Characteristics of quality-assured culture substrata (RAL-GZ 252, 2006) - Permissible substrata-
source and inert materials of assured quality or equivalent products
Quality feature
Fine composition
Average composition
Coarse composition
pH (CaCl ), overall
2
pH (CaC ) for azaleas, ericas, boggy soil
2
Salt content (as KCl), overall
Salt content (as KCl) for azaleas, ericas, boggy
soil
48
Plant absorption for elements with
Grouping
of values a) High fb value
(N,CI,S)
very minimal insufficient
minimal moderate
moderate sufficient
mid-level good
high good
very high very good
critically high too strong
leads to visual da-
damaging
mage, toxic range
b) Mid-level fb value
(K, Na, Ca, Mg, B, Mo)
obstructed
too low
moderate
sufficient
good
very good
inharmonious
So now when we wish to understand the
nutrient potential, it is important to determine
not the quantity of dissolved elements in the
soil but the activity of these elements.
Permitted value range
Quantity of oversized particles > 10 mm
Maximum 5 vol.-% incl. fibres
Quantity of oversized particles > 20 mm
Maximum 5 vol.-% without fibres
Quantity of oversized particles > 40 mm
Maximum 10 vol.-% without fibres
5.0 to 6.5
3.4 to 4.6
< 3.0 g/l
< 1.0 g/l
c) Low fb value
(P, Fe, Mn, Zn, Cu, Al)
very obstructed
insufficient
still too low
moderate
good
very good
inharmonious