The other preliminary analysis was to estimate W p /W s value for each sample.
Assuming that volcanic glass quantitatively weathered to form Al o materials, and the
average Al content of volcanic glass in the andesitic volcanic ash is 69.6 g kg
À1
(Kobayashi et al. 1976); W p /W s was calculated as follows on an ignition residue basis:
W p =W s ¼ OIIR þ Al o =69:6
ð4:1Þ
where OIIR (kg kg
À1 ) is the oxalate-insoluble residue, and was determined
experimentally.
In Fig. 4.30, the ideal concentration changes of immobile elements were also
drawn as a red line. The use of the red lines in this figure is based on the open-system
mass transport that yields the chemical gain and losses of elements in a soil sample
compared with the parent material after Brimhall et al. (1991) and Nieuwenhuyse
and van Breemen (1997). For immobile elements, their equation can be simplified by
multiplying the volume by the bulk density to give Eq. (4.2) (Kurtz et al. 2000):
W p E j, p ¼ W s E j, s
ð4:2Þ
Equation (4.2) is further converted to Eq. (4.3):
E j, s ¼ W p =W s
À
Á
E j, p
ð4:3Þ
Fig. 4.28 Polished section of a clod from the 3Bw5 horizon of Fig. 4.19a. (a) Optical micrograph,
(b) SEM image, (c and d) Al and Si element maps, respectively
4.4 Andisols: Soils Dominated by Non-crystalline Inorganic Constituents
89
Assuming that volcanic glass quantitatively weathered to form Al o materials, and the
average Al content of volcanic glass in the andesitic volcanic ash is 69.6 g kg
À1
(Kobayashi et al. 1976); W p /W s was calculated as follows on an ignition residue basis:
W p =W s ¼ OIIR þ Al o =69:6
ð4:1Þ
where OIIR (kg kg
À1 ) is the oxalate-insoluble residue, and was determined
experimentally.
In Fig. 4.30, the ideal concentration changes of immobile elements were also
drawn as a red line. The use of the red lines in this figure is based on the open-system
mass transport that yields the chemical gain and losses of elements in a soil sample
compared with the parent material after Brimhall et al. (1991) and Nieuwenhuyse
and van Breemen (1997). For immobile elements, their equation can be simplified by
multiplying the volume by the bulk density to give Eq. (4.2) (Kurtz et al. 2000):
W p E j, p ¼ W s E j, s
ð4:2Þ
Equation (4.2) is further converted to Eq. (4.3):
E j, s ¼ W p =W s
À
Á
E j, p
ð4:3Þ
Fig. 4.28 Polished section of a clod from the 3Bw5 horizon of Fig. 4.19a. (a) Optical micrograph,
(b) SEM image, (c and d) Al and Si element maps, respectively
4.4 Andisols: Soils Dominated by Non-crystalline Inorganic Constituents
89