Soil Analysis Procedure; Sampling; Weighing And Determination Of Moisture Content; Sieving The Soil Sample - MACHEREY-NAGEL VISOCOLOR Manual

2. Soil analysis procedure

2.1 Sampling

Take several samples from various locations of the area to be
examined and mix them. Do not take samples after prolonged or
strong rainfall. Soil from arable land should be taken after the har-
vest and prior to fertilizing. Grassland can be analyzed in spring
and winter or after each cut. The sampling depth is 10 cm for
lawns and grassland, 15–30 cm for arable land and 30 cm for
vegetable beds and shrub areas.
The samples can be taken with a spade; soil drills are required
for examining the deeper layers of soil at depths of 30–60 cm and
60–90 cm.
Prior to the analysis, remove all untypical parts such as stones,
parts of plants and other items (glass, metal, pieces of plastic,
etc.).
The sample is then weighed and dried, and the moisture content
and density of the soil are determined (see 2.2, page 23, see
2.4, page 23).

2.2 Weighing and determination of moisture content

1. Set up balance (1)
2. Place plastic beaker (17) on the balance pan
3. Tare to ZERO
4. Weigh the required quantity of soil with the aid of the plastic
scoop (18)
Determination of moisture content:
Weigh 200 g of the soil sample and spread evenly over one of
the cardboard sheets (210 x 297 mm). Crush any large clumps
of soil and dry in a well-ventilated room at room temperature for
16–24 hours.
After drying, pour the soil sample back into the tared measuring
beaker and establish its weight.
Calculation of the moisture content of the soil.
Weight of moist soil [ g ] – Weight of dry soil [ g ]
Weight of moist soil [ g ]
1
17

2.3 Sieving the soil sample

Prior to the preparation of the soil extracts and the determination
the soil density and soil structure (sedimentation) of the sample
is screened. The mesh width is 2 mm. This means that all par-
ticles larger than 2 mm are removed from the sample. Analytical
values from screened samples provide improved comparability,
Manual VISOCOLOR
Manual VISOCOLOR
% soil
x 100 =
moisture
210 x 279 mm
18
®
reagent case for soil analysis 02.19
®
reagent case for soil analysis
as the accuracy and precision of the individual examination are
increased.
Place the air-dry sample on the sieve (2) in portions, carefully
crushing large clumps of earth beforehand. Screen the soil onto
a clean cardboard sheet 210 x 297 mm. Discard the material re-
tained by the sieve. The material obtained in this manner is used
to prepare the soil extracts.
2

2.4 Determination of the soil density

Soils consist of grains of varying sizes and shapes. The specific
weights of the constituent parts, and the pore volume result in the
3
soil density (kg/dm ). We determine the soil density on the basis
of the air-dry, screened soils.
Procedure:
Insert the 100 mL measuring cylinder (8) into the green plastic
base (9). Place the cylinder onto the balance (1) and write down
its weight. Take the cylinder off the balance and fill with sieved
soil using the plastic shovel (18). Compact the soil by gently
tapping the cylinder on a solid surface until the 100 mL mark is
reached, or read the respective volume. If necessary, level the
surface without exerting any pressure (in case the soil quantity is
not sufficient, write down the respective volume). Place measur-
ing cylinder on the balance and read weight.
ml 100
90
80
70
60
50
40
30
20
10
8 9
Calculation:
[
D
dm
A = Soil weight D = Soil density
210 x 297 mm
18
1
kg A [g]
] =
3
V [mL]
V = Volume
23