Segundo Taller de la Red Latinoamericana de Laboratorios de Suelos (LATSOLAN) 12-14 marzo 2019 Ciudad de México

1. Item 14:
Description of the Second Ring Test 2019
LATSOLAN-SEALNET
Sr. Armando Guerrero, México
Sra. Nopmanee Suvannang, Thailand

2. Propuestas adicionales para el Segundo
RING TEST (SEALNET-LATSOLAN)
SEALNET
pH water 1:2.5
OC (WB)
Exch Ca,Mg,K,
Na(NH4OAc)
Total C
Total N
Avail P (Olsen, Bray)
EC 1:5
LATSOLAN
pH agua 1:2.5
COx (WB)
Ca, Mg, K , Na (NH4OAc)
C total
N total
N total (Kj)
CaCO3
P intercambiable (Olsen?, Bray?)
CE 1:5?

3. Test Item for PT
2018 2019 2020 2018 2019 2020 2018 2019 2020
pHwater 1:2.5 × × × × ×
OC (WB) × × × × ×
OC (dry combustion) × × ×
Avail P (Olsen) × × × ×
Exch K × × × × ×
Exch Ca × × × ×
Exch Mg × × × ×
Exch Na × × ×
CEC × × ×
EC 1:5 × × ×
Avail P (Bray 1) × × ×
Avail P (Bray 2) × × ×
GLOSOLAN SEALNET LATSOLAN

4. Core questions to be answered
- What is the Participation scheme
- How the sample will delivery to the
participating laboratories
- What is the decisions on SOPs to be used

5. GSP
purchase the soil samples and sent to
participating laboratories
Structure of Global PT 2019
sent by hand
(LATSOLAN)
sent by FAO
office
(Other regions)
GSP
purchase the soil samples and sent to
participating laboratories
participating labs analyte PT
samples

6. SEALNET 18
LATSOLAN (11 Central America + 9 South America) 20
PACIFIC 3
EUROPE and EURASIA : 8?
AFRICA 50?
NENA 4
NORTH AMERICA 1
TOTAL 104
Region Participating Laboratory
no of labs participate
2019

7. What is the decisions on SOPs to be used
• SEALNET-LATSOLAN SOP
• Individual lab SOP
• 1 & 2

8. pH water 1:2.5
Region Amount
ofsoil
volume
ofwater
ratio type ofwater particle
size
(mm)
type of
agitation
Agitation
time
restingtime againshake
andreadin
the
suspension
electrode immersiondepth Form of
expression
ofthe
result
SEALNET-
LATSOLAN
SOPpH
10g 25ml 1:2.5 Deionized/distilled
water The pHof
the watershould
be between5.6
and7.0
2mm shaker 10min 60min yes insertthe electrode intothe
suspension
1decimal

9. Region
Mass range
of soil
sample
analyzed, in
g (minimum-
maximum)
Particle
size of
the soil
sample
(mm)
Molarity of
Potassium
Dichromate
that uses
ml of
dichromate
used
(range,
according
to the soil
mass used)
ml of
Sulfuric
Acid
used
(range,
according
to the
mass
used)
ratio
Add
external
heat?
If yes, how
long, what
temperature
(° C) and
by what
means?
Time
(min) of
rest of
the
reaction
amount
of water
use
(ml)
Type of water
used,
according to
ASTM
need addition
filtration
Does your
method
require
adding
Phosphoric
Acid?
If you use
Phosphoric
Acid, how
many mL?
How do you
evaluate the
excess of
Dichromate?
SEALNET_
LATSOLAN
SOP OC
(WB)
0.5 -1.0 g of
air dry soil
(adjust if
necessary,w
ith colour
of soil)
0.5 mm
sieve
0.167 M
or 1 N
10 ml 20 ml 1:2 no - 30 min 200 ml deionized/
distilled water
filter the
suspension
using an acid
resistant filter
paper (e.g.
Whatman No.
540), if
experience
shows that the
end point of
the titration
cannot
otherwise be
clearly
discerned.
yes
if
diphenylami
ne
indicator is
used
10 mL of
85% H3PO4.
titration
OC (WB)

10. Region
massofsoil
sample
analyzeding
Particle size of
the soil
sample (mm)
extractant
Totalvolume
ofextractor
solution
ratio addchacoal
How do
you
perform
the
extraction?
Agitationtime
andnumberof
times
Ifyoufilter,
what#offilter
paperdoyou
use?
time to
develop
colour
wavle
length
used
calculation
base onair
dry soilor
ovendry
SEALNET 5g 2mm 0.5M
NaHCO3 at
pH8.5
100ml 1:20 Addahalf
teaspoonofP-
free carbon
black(approx.
0.5g).
shaking 30min
at25 ͦC
whatmanNo
42
60min 882nm ovendry soil
basis
LATSOLAN
P (Olsen)

11. Regional
pH of
Ammonium
Acetate
mass of
soil
sample
analyzed
in g
Particle
size of
the soil
sample
(mm)
Total
volume of
extractor
solution
ratio
How do you
performthe
extraction?
With what type
of equipment
does the
agitation?
How do you
separate
the phases?
Agitation
time and
number
of times
If you filter,
what # of
filter paper
do you use?
What conc
do you
use for K
calibration?
calculatio
n base
on air dry
soilor
oven dry
SEALNET ammonium
acetate
(pH=7, N=1)
2.5 g 2 mm 25 ml 1:10 reciprocating
shaker for 30
minutes
reciprocating
shaker
filter 30 min
only 1
time
Whatman
No. 2 filter
paper
contain 0,
5, 10, 15,
20, and 40
ppmK
air dry
soil
LATSOLAN ammonium
acetate
(pH=7, N=1)
5 g 2 mm 100 ml
(33 ml* 3
time
shaking)
1:20 reciprocating
shaker for 10
minutes
reciprocating
shaker
centriguge
and filter
10 min
repeat 3
time
Whatman 2,
41 or similar
paper.
contain 0,
5, 10, 20,
30, and 40
ppmK
air dry
soil
Exch Ca, Mg, K and Na (NH4OAc)

12. EC 1:5
Region Amount
of soil
volume
of water
ratio temp type of water particle
size
(mm)
type of
agitation
shaking
time
filter
yes/No
resting time again
shake and
read in the
suspensio
n
electrode
immersion
depth
Form of
expressi
on of
the
result
American Society of
Agronomy , Inc. and
Soil Science Society
of America, Inc. Soil
AnalysisPart2:
Electrical
Conductivity,1982,
USA
10 g 50 ml 1:5 Deionized/distilled water
The pH of the water
should be between 5.6
and 7.0
2 mm shaker 60 min yes - no insert the
electrode
into the clear
solution
1
decimal
10 g 50 ml 1:5 Deionized/distilled water
The pH of the water
should be between 5.6
and 7.0
2 mm shaker 30 min yes - no insert the
electrode
into the clear
solution
1
decimal
Bower, C.A. and L.V.
Wilcox. 1965. Soluble
Salts. In Black, C.A., et
al., Eds., Methods of
Soil Analysis, Part 2,
American Society of
Agronomy, Madison, p.
933-951.
10 g 50 ml 1:5 Deionized/distilled water
The pH of the water
should be between 5.6
and 7.0
2 mm shaker 60 min - - no insert the
electrode
into the clear
solution
1
decimal
ISO 11265_1994 20 g 100 ml 1:5 20 ͦ C Deionized/distilled water
The pH of the water
should be between 5.6
and 7.0
2 mm shaker 30 min yes - no insert the
electrode
into the clear
solution
1
decimal

13. Gracias por su atención