of sclerotia grains from environmental fluctuations by the overlying tephra layer,
perhaps leading to higher reproducibility than samples from surficial A horizons.
The mean temperature and annual precipitation in the area are 5.8
C and
2280 mm, respectively. Vegetation at the site is characterized by the presence of
Fagus crenata and Sasa kurilensis. Sclerotia grains were collected from soil samples
in the laboratory using tweezers and then placed into a plastic tube with 50 mL of
distilled water for ultrasonic cleaning of the surface (US-1 generator, Iuchi
(AS ONE) Corp., Osaka, Japan) at 70 W and 38 kHz for 5 min. The cleaned grains
were air-dried at 25
C for 1 week. Approximately 5 g (ca. 1000 grains) were
preserved in a plastic bottle at room temperature as a standard sclerotia grain sample.
For analyses on grain size, volume, specific gravity, and SEM-EDS measurements,
samples were provided by grains. For chemical analysis, grains were chosen at
random and ground to a fine powder (<5 μm) in a clean agate mortar.
5.3 Grain Size, Volume, and Specific Gravity of Sclerotia
The weight and diameter of the sclerotia grains were measured using an analytical
balance (AX26, Mettler Toledo, Columbus, OH, USA) and a digital high-density
video microscope (VH-7000, Keyence, Osaka, Japan), respectively. Spherical grains
Fig. 5.1 Profile of
Mt. Myoko soil (left).
Standard samples were
collected from the 3A
horizon. Sclerotia grains
collected from the Myoko
3A horizon (right)
Table 5.1 Soil properties of the Myoko soil profile. Horizons 1C and 2C correspond to Koyaike
ash-b and Koyaike ash-c, derived from the eruption of Yakeyama volcano in 650 Æ 100 years. BP
and 950 Æ 80 years. BP, respectively (Hayatsu et al. 1994). T-C and T-N represent total carbon and
nitrogen contents, respectively
Horizon
Depth, cm
Soil pH
T-C
T-N
C/N ratio
H 2 O
KCl
%
1A
0–11
5.20
3.70
19.0
1.10
17.0
1C
11–15
5.00
4.20
5.20
0.27
19.0
2A
15–20
5.20
4.30
7.90
0.43
18.0
2C
20–26
5.20
4.50
4.40
0.26
17.0
3A
26–34
5.40
4.40
9.20
0.46
20.0
3Bw
345.30
4.50
6.50
0.35
19.0
5 Chemical Characterization of Sclerotia Grains Collected from a Volcanic Ash. . .
79
perhaps leading to higher reproducibility than samples from surficial A horizons.
The mean temperature and annual precipitation in the area are 5.8
C and
2280 mm, respectively. Vegetation at the site is characterized by the presence of
Fagus crenata and Sasa kurilensis. Sclerotia grains were collected from soil samples
in the laboratory using tweezers and then placed into a plastic tube with 50 mL of
distilled water for ultrasonic cleaning of the surface (US-1 generator, Iuchi
(AS ONE) Corp., Osaka, Japan) at 70 W and 38 kHz for 5 min. The cleaned grains
were air-dried at 25
C for 1 week. Approximately 5 g (ca. 1000 grains) were
preserved in a plastic bottle at room temperature as a standard sclerotia grain sample.
For analyses on grain size, volume, specific gravity, and SEM-EDS measurements,
samples were provided by grains. For chemical analysis, grains were chosen at
random and ground to a fine powder (<5 μm) in a clean agate mortar.
5.3 Grain Size, Volume, and Specific Gravity of Sclerotia
The weight and diameter of the sclerotia grains were measured using an analytical
balance (AX26, Mettler Toledo, Columbus, OH, USA) and a digital high-density
video microscope (VH-7000, Keyence, Osaka, Japan), respectively. Spherical grains
Fig. 5.1 Profile of
Mt. Myoko soil (left).
Standard samples were
collected from the 3A
horizon. Sclerotia grains
collected from the Myoko
3A horizon (right)
Table 5.1 Soil properties of the Myoko soil profile. Horizons 1C and 2C correspond to Koyaike
ash-b and Koyaike ash-c, derived from the eruption of Yakeyama volcano in 650 Æ 100 years. BP
and 950 Æ 80 years. BP, respectively (Hayatsu et al. 1994). T-C and T-N represent total carbon and
nitrogen contents, respectively
Horizon
Depth, cm
Soil pH
T-C
T-N
C/N ratio
H 2 O
KCl
%
1A
0–11
5.20
3.70
19.0
1.10
17.0
1C
11–15
5.00
4.20
5.20
0.27
19.0
2A
15–20
5.20
4.30
7.90
0.43
18.0
2C
20–26
5.20
4.50
4.40
0.26
17.0
3A
26–34
5.40
4.40
9.20
0.46
20.0
3Bw
345.30
4.50
6.50
0.35
19.0
5 Chemical Characterization of Sclerotia Grains Collected from a Volcanic Ash. . .
79